From 6716671d8c1c07a8072098764d1b7cbfef7412ad Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 23 Mar 2011 10:48:35 +0100 Subject: TTY: introduce deinit helpers for proper ldisc shutdown Introduce deinitialize_tty_struct which should be called after initialize_tty_struct and before successfull tty_ldisc_setup. It calls tty_ldisc_deinit which is opposite of tty_ldisc_init. It only puts a reference to ldisc and assigns NULL to tty->ldisc. It will be used to shut down ldisc when tty_release cannot be called yet. Signed-off-by: Jiri Slaby Cc: Alan Cox Cc: Julian Anastasov Signed-off-by: Greg Kroah-Hartman --- include/linux/tty.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/tty.h b/include/linux/tty.h index 9f469c700550..4db4ca79f895 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -472,6 +472,7 @@ extern int tty_add_file(struct tty_struct *tty, struct file *file); extern void free_tty_struct(struct tty_struct *tty); extern void initialize_tty_struct(struct tty_struct *tty, struct tty_driver *driver, int idx); +extern void deinitialize_tty_struct(struct tty_struct *tty); extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, int first_ok); extern int tty_release(struct inode *inode, struct file *filp); @@ -525,6 +526,7 @@ extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); extern void tty_ldisc_init(struct tty_struct *tty); +extern void tty_ldisc_deinit(struct tty_struct *tty); extern void tty_ldisc_begin(void); /* This last one is just for the tty layer internals and shouldn't be used elsewhere */ extern void tty_ldisc_enable(struct tty_struct *tty); -- cgit v1.3-14-g43fede From b1c43f82c5aa265442f82dba31ce985ebb7aa71c Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Mon, 21 Mar 2011 12:25:08 +0200 Subject: tty: make receive_buf() return the amout of bytes received it makes it simpler to keep track of the amount of bytes received and simplifies how flush_to_ldisc counts the remaining bytes. It also fixes a bug of lost bytes on n_tty when flushing too many bytes via the USB serial gadget driver. Tested-by: Stefan Bigler Tested-by: Toby Gray Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/bluetooth/hci_ldisc.c | 12 +++++--- drivers/input/serio/serport.c | 10 +++++-- drivers/isdn/gigaset/ser-gigaset.c | 8 +++-- drivers/misc/ti-st/st_core.c | 6 ++-- drivers/net/caif/caif_serial.c | 6 ++-- drivers/net/can/slcan.c | 9 ++++-- drivers/net/hamradio/6pack.c | 8 +++-- drivers/net/hamradio/mkiss.c | 11 ++++--- drivers/net/irda/irtty-sir.c | 16 +++++----- drivers/net/ppp_async.c | 6 ++-- drivers/net/ppp_synctty.c | 6 ++-- drivers/net/slip.c | 11 ++++--- drivers/net/wan/x25_asy.c | 7 +++-- drivers/tty/n_gsm.c | 6 ++-- drivers/tty/n_hdlc.c | 18 ++++++----- drivers/tty/n_r3964.c | 10 ++++--- drivers/tty/n_tty.c | 61 +++++++++----------------------------- drivers/tty/tty_buffer.c | 15 ++++++---- drivers/tty/vt/selection.c | 3 +- include/linux/tty_ldisc.h | 9 +++--- 20 files changed, 125 insertions(+), 113 deletions(-) (limited to 'include/linux') diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index 48ad2a7ab080..0d4da5e14ba0 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -357,22 +357,26 @@ static void hci_uart_tty_wakeup(struct tty_struct *tty) * * Return Value: None */ -static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data, char *flags, int count) +static unsigned int hci_uart_tty_receive(struct tty_struct *tty, + const u8 *data, char *flags, int count) { struct hci_uart *hu = (void *)tty->disc_data; + int received; if (!hu || tty != hu->tty) - return; + return -ENODEV; if (!test_bit(HCI_UART_PROTO_SET, &hu->flags)) - return; + return -EINVAL; spin_lock(&hu->rx_lock); - hu->proto->recv(hu, (void *) data, count); + received = hu->proto->recv(hu, (void *) data, count); hu->hdev->stat.byte_rx += count; spin_unlock(&hu->rx_lock); tty_unthrottle(tty); + + return received; } static int hci_uart_register_dev(struct hci_uart *hu) diff --git a/drivers/input/serio/serport.c b/drivers/input/serio/serport.c index 8755f5f3ad37..f3698967edf6 100644 --- a/drivers/input/serio/serport.c +++ b/drivers/input/serio/serport.c @@ -120,17 +120,21 @@ static void serport_ldisc_close(struct tty_struct *tty) * 'interrupt' routine. */ -static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) +static unsigned int serport_ldisc_receive(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct serport *serport = (struct serport*) tty->disc_data; unsigned long flags; unsigned int ch_flags; + int ret = 0; int i; spin_lock_irqsave(&serport->lock, flags); - if (!test_bit(SERPORT_ACTIVE, &serport->flags)) + if (!test_bit(SERPORT_ACTIVE, &serport->flags)) { + ret = -EINVAL; goto out; + } for (i = 0; i < count; i++) { switch (fp[i]) { @@ -152,6 +156,8 @@ static void serport_ldisc_receive(struct tty_struct *tty, const unsigned char *c out: spin_unlock_irqrestore(&serport->lock, flags); + + return ret == 0 ? count : ret; } /* diff --git a/drivers/isdn/gigaset/ser-gigaset.c b/drivers/isdn/gigaset/ser-gigaset.c index 86a5c4f7775e..1d44d470897c 100644 --- a/drivers/isdn/gigaset/ser-gigaset.c +++ b/drivers/isdn/gigaset/ser-gigaset.c @@ -674,7 +674,7 @@ gigaset_tty_ioctl(struct tty_struct *tty, struct file *file, * cflags buffer containing error flags for received characters (ignored) * count number of received characters */ -static void +static unsigned int gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, char *cflags, int count) { @@ -683,12 +683,12 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, struct inbuf_t *inbuf; if (!cs) - return; + return -ENODEV; inbuf = cs->inbuf; if (!inbuf) { dev_err(cs->dev, "%s: no inbuf\n", __func__); cs_put(cs); - return; + return -EINVAL; } tail = inbuf->tail; @@ -725,6 +725,8 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, gig_dbg(DEBUG_INTR, "%s-->BH", __func__); gigaset_schedule_event(cs); cs_put(cs); + + return count; } /* diff --git a/drivers/misc/ti-st/st_core.c b/drivers/misc/ti-st/st_core.c index 486117f72c9f..cb98a7da98ef 100644 --- a/drivers/misc/ti-st/st_core.c +++ b/drivers/misc/ti-st/st_core.c @@ -744,8 +744,8 @@ static void st_tty_close(struct tty_struct *tty) pr_debug("%s: done ", __func__); } -static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, - char *tty_flags, int count) +static unsigned int st_tty_receive(struct tty_struct *tty, + const unsigned char *data, char *tty_flags, int count) { #ifdef VERBOSE print_hex_dump(KERN_DEBUG, ">in>", DUMP_PREFIX_NONE, @@ -758,6 +758,8 @@ static void st_tty_receive(struct tty_struct *tty, const unsigned char *data, */ st_recv(tty->disc_data, data, count); pr_debug("done %s", __func__); + + return count; } /* wake-up function called in from the TTY layer diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c index 3df0c0f8b8bf..73c7e03617ec 100644 --- a/drivers/net/caif/caif_serial.c +++ b/drivers/net/caif/caif_serial.c @@ -167,8 +167,8 @@ static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size) #endif -static void ldisc_receive(struct tty_struct *tty, const u8 *data, - char *flags, int count) +static unsigned int ldisc_receive(struct tty_struct *tty, + const u8 *data, char *flags, int count) { struct sk_buff *skb = NULL; struct ser_device *ser; @@ -215,6 +215,8 @@ static void ldisc_receive(struct tty_struct *tty, const u8 *data, } else ++ser->dev->stats.rx_dropped; update_tty_status(ser); + + return count; } static int handle_tx(struct ser_device *ser) diff --git a/drivers/net/can/slcan.c b/drivers/net/can/slcan.c index b423965a78d1..c600954998d5 100644 --- a/drivers/net/can/slcan.c +++ b/drivers/net/can/slcan.c @@ -425,16 +425,17 @@ static void slc_setup(struct net_device *dev) * in parallel */ -static void slcan_receive_buf(struct tty_struct *tty, +static unsigned int slcan_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) { struct slcan *sl = (struct slcan *) tty->disc_data; + int bytes = count; if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev)) - return; + return -ENODEV; /* Read the characters out of the buffer */ - while (count--) { + while (bytes--) { if (fp && *fp++) { if (!test_and_set_bit(SLF_ERROR, &sl->flags)) sl->dev->stats.rx_errors++; @@ -443,6 +444,8 @@ static void slcan_receive_buf(struct tty_struct *tty, } slcan_unesc(sl, *cp++); } + + return count; } /************************************ diff --git a/drivers/net/hamradio/6pack.c b/drivers/net/hamradio/6pack.c index 3e5d0b6b6516..992089639ea4 100644 --- a/drivers/net/hamradio/6pack.c +++ b/drivers/net/hamradio/6pack.c @@ -456,7 +456,7 @@ out: * a block of 6pack data has been received, which can now be decapsulated * and sent on to some IP layer for further processing. */ -static void sixpack_receive_buf(struct tty_struct *tty, +static unsigned int sixpack_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) { struct sixpack *sp; @@ -464,11 +464,11 @@ static void sixpack_receive_buf(struct tty_struct *tty, int count1; if (!count) - return; + return 0; sp = sp_get(tty); if (!sp) - return; + return -ENODEV; memcpy(buf, cp, count < sizeof(buf) ? count : sizeof(buf)); @@ -487,6 +487,8 @@ static void sixpack_receive_buf(struct tty_struct *tty, sp_put(sp); tty_unthrottle(tty); + + return count1; } /* diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c index 4c628393c8b1..0e4f23531140 100644 --- a/drivers/net/hamradio/mkiss.c +++ b/drivers/net/hamradio/mkiss.c @@ -923,13 +923,14 @@ static long mkiss_compat_ioctl(struct tty_struct *tty, struct file *file, * a block of data has been received, which can now be decapsulated * and sent on to the AX.25 layer for further processing. */ -static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int mkiss_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct mkiss *ax = mkiss_get(tty); + int bytes = count; if (!ax) - return; + return -ENODEV; /* * Argh! mtu change time! - costs us the packet part received @@ -939,7 +940,7 @@ static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp, ax_changedmtu(ax); /* Read the characters out of the buffer */ - while (count--) { + while (bytes--) { if (fp != NULL && *fp++) { if (!test_and_set_bit(AXF_ERROR, &ax->flags)) ax->dev->stats.rx_errors++; @@ -952,6 +953,8 @@ static void mkiss_receive_buf(struct tty_struct *tty, const unsigned char *cp, mkiss_put(ax); tty_unthrottle(tty); + + return count; } /* diff --git a/drivers/net/irda/irtty-sir.c b/drivers/net/irda/irtty-sir.c index 3352b2443e58..035861d8acb1 100644 --- a/drivers/net/irda/irtty-sir.c +++ b/drivers/net/irda/irtty-sir.c @@ -216,23 +216,23 @@ static int irtty_do_write(struct sir_dev *dev, const unsigned char *ptr, size_t * usbserial: urb-complete-interrupt / softint */ -static void irtty_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int irtty_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct sir_dev *dev; struct sirtty_cb *priv = tty->disc_data; int i; - IRDA_ASSERT(priv != NULL, return;); - IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return;); + IRDA_ASSERT(priv != NULL, return -ENODEV;); + IRDA_ASSERT(priv->magic == IRTTY_MAGIC, return -EINVAL;); if (unlikely(count==0)) /* yes, this happens */ - return; + return 0; dev = priv->dev; if (!dev) { IRDA_WARNING("%s(), not ready yet!\n", __func__); - return; + return -ENODEV; } for (i = 0; i < count; i++) { @@ -242,11 +242,13 @@ static void irtty_receive_buf(struct tty_struct *tty, const unsigned char *cp, if (fp && *fp++) { IRDA_DEBUG(0, "Framing or parity error!\n"); sirdev_receive(dev, NULL, 0); /* notify sir_dev (updating stats) */ - return; + return -EINVAL; } } sirdev_receive(dev, cp, count); + + return count; } /* diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c index a1b82c9c67d2..53872d7d7382 100644 --- a/drivers/net/ppp_async.c +++ b/drivers/net/ppp_async.c @@ -340,7 +340,7 @@ ppp_asynctty_poll(struct tty_struct *tty, struct file *file, poll_table *wait) } /* May sleep, don't call from interrupt level or with interrupts disabled */ -static void +static unsigned int ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf, char *cflags, int count) { @@ -348,7 +348,7 @@ ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf, unsigned long flags; if (!ap) - return; + return -ENODEV; spin_lock_irqsave(&ap->recv_lock, flags); ppp_async_input(ap, buf, cflags, count); spin_unlock_irqrestore(&ap->recv_lock, flags); @@ -356,6 +356,8 @@ ppp_asynctty_receive(struct tty_struct *tty, const unsigned char *buf, tasklet_schedule(&ap->tsk); ap_put(ap); tty_unthrottle(tty); + + return count; } static void diff --git a/drivers/net/ppp_synctty.c b/drivers/net/ppp_synctty.c index 2573f525f11c..0815790a5cf9 100644 --- a/drivers/net/ppp_synctty.c +++ b/drivers/net/ppp_synctty.c @@ -381,7 +381,7 @@ ppp_sync_poll(struct tty_struct *tty, struct file *file, poll_table *wait) } /* May sleep, don't call from interrupt level or with interrupts disabled */ -static void +static unsigned int ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf, char *cflags, int count) { @@ -389,7 +389,7 @@ ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf, unsigned long flags; if (!ap) - return; + return -ENODEV; spin_lock_irqsave(&ap->recv_lock, flags); ppp_sync_input(ap, buf, cflags, count); spin_unlock_irqrestore(&ap->recv_lock, flags); @@ -397,6 +397,8 @@ ppp_sync_receive(struct tty_struct *tty, const unsigned char *buf, tasklet_schedule(&ap->tsk); sp_put(ap); tty_unthrottle(tty); + + return count; } static void diff --git a/drivers/net/slip.c b/drivers/net/slip.c index 86cbb9ea2f26..86718d358395 100644 --- a/drivers/net/slip.c +++ b/drivers/net/slip.c @@ -670,16 +670,17 @@ static void sl_setup(struct net_device *dev) * in parallel */ -static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int slip_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct slip *sl = tty->disc_data; + int bytes = count; if (!sl || sl->magic != SLIP_MAGIC || !netif_running(sl->dev)) - return; + return -ENODEV; /* Read the characters out of the buffer */ - while (count--) { + while (bytes--) { if (fp && *fp++) { if (!test_and_set_bit(SLF_ERROR, &sl->flags)) sl->dev->stats.rx_errors++; @@ -693,6 +694,8 @@ static void slip_receive_buf(struct tty_struct *tty, const unsigned char *cp, #endif slip_unesc(sl, *cp++); } + + return count; } /************************************ diff --git a/drivers/net/wan/x25_asy.c b/drivers/net/wan/x25_asy.c index 24297b274cd4..40398bf7d036 100644 --- a/drivers/net/wan/x25_asy.c +++ b/drivers/net/wan/x25_asy.c @@ -517,17 +517,18 @@ static int x25_asy_close(struct net_device *dev) * and sent on to some IP layer for further processing. */ -static void x25_asy_receive_buf(struct tty_struct *tty, +static unsigned int x25_asy_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) { struct x25_asy *sl = tty->disc_data; + int bytes = count; if (!sl || sl->magic != X25_ASY_MAGIC || !netif_running(sl->dev)) return; /* Read the characters out of the buffer */ - while (count--) { + while (bytes--) { if (fp && *fp++) { if (!test_and_set_bit(SLF_ERROR, &sl->flags)) sl->dev->stats.rx_errors++; @@ -536,6 +537,8 @@ static void x25_asy_receive_buf(struct tty_struct *tty, } x25_asy_unesc(sl, *cp++); } + + return count; } /* diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 47f8cdb207f1..6abc73598847 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2138,8 +2138,8 @@ static void gsmld_detach_gsm(struct tty_struct *tty, struct gsm_mux *gsm) gsm->tty = NULL; } -static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int gsmld_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct gsm_mux *gsm = tty->disc_data; const unsigned char *dp; @@ -2173,6 +2173,8 @@ static void gsmld_receive_buf(struct tty_struct *tty, const unsigned char *cp, } /* FASYNC if needed ? */ /* If clogged call tty_throttle(tty); */ + + return count; } /** diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index cea56033b34c..cac666314aef 100644 --- a/drivers/tty/n_hdlc.c +++ b/drivers/tty/n_hdlc.c @@ -188,8 +188,8 @@ static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp, poll_table *wait); static int n_hdlc_tty_open(struct tty_struct *tty); static void n_hdlc_tty_close(struct tty_struct *tty); -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *cp, - char *fp, int count); +static unsigned int n_hdlc_tty_receive(struct tty_struct *tty, + const __u8 *cp, char *fp, int count); static void n_hdlc_tty_wakeup(struct tty_struct *tty); #define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f))) @@ -509,8 +509,8 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty) * Called by tty low level driver when receive data is available. Data is * interpreted as one HDLC frame. */ -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, - char *flags, int count) +static unsigned int n_hdlc_tty_receive(struct tty_struct *tty, + const __u8 *data, char *flags, int count) { register struct n_hdlc *n_hdlc = tty2n_hdlc (tty); register struct n_hdlc_buf *buf; @@ -521,20 +521,20 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, /* This can happen if stuff comes in on the backup tty */ if (!n_hdlc || tty != n_hdlc->tty) - return; + return -ENODEV; /* verify line is using HDLC discipline */ if (n_hdlc->magic != HDLC_MAGIC) { printk("%s(%d) line not using HDLC discipline\n", __FILE__,__LINE__); - return; + return -EINVAL; } if ( count>maxframe ) { if (debuglevel >= DEBUG_LEVEL_INFO) printk("%s(%d) rx count>maxframesize, data discarded\n", __FILE__,__LINE__); - return; + return -EINVAL; } /* get a free HDLC buffer */ @@ -550,7 +550,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, if (debuglevel >= DEBUG_LEVEL_INFO) printk("%s(%d) no more rx buffers, data discarded\n", __FILE__,__LINE__); - return; + return -EINVAL; } /* copy received data to HDLC buffer */ @@ -565,6 +565,8 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, if (n_hdlc->tty->fasync != NULL) kill_fasync (&n_hdlc->tty->fasync, SIGIO, POLL_IN); + return count; + } /* end of n_hdlc_tty_receive() */ /** diff --git a/drivers/tty/n_r3964.c b/drivers/tty/n_r3964.c index 5c6c31459a2f..a4bc39c21a43 100644 --- a/drivers/tty/n_r3964.c +++ b/drivers/tty/n_r3964.c @@ -139,8 +139,8 @@ static int r3964_ioctl(struct tty_struct *tty, struct file *file, static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, struct poll_table_struct *wait); -static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count); +static unsigned int r3964_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count); static struct tty_ldisc_ops tty_ldisc_N_R3964 = { .owner = THIS_MODULE, @@ -1239,8 +1239,8 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file, return result; } -static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int r3964_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { struct r3964_info *pInfo = tty->disc_data; const unsigned char *p; @@ -1257,6 +1257,8 @@ static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, } } + + return count; } MODULE_LICENSE("GPL"); diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 0ad32888091c..95d0a9c2dd13 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -81,38 +81,6 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x, return put_user(x, ptr); } -/** - * n_tty_set__room - receive space - * @tty: terminal - * - * Called by the driver to find out how much data it is - * permitted to feed to the line discipline without any being lost - * and thus to manage flow control. Not serialized. Answers for the - * "instant". - */ - -static void n_tty_set_room(struct tty_struct *tty) -{ - /* tty->read_cnt is not read locked ? */ - int left = N_TTY_BUF_SIZE - tty->read_cnt - 1; - int old_left; - - /* - * If we are doing input canonicalization, and there are no - * pending newlines, let characters through without limit, so - * that erase characters will be handled. Other excess - * characters will be beeped. - */ - if (left <= 0) - left = tty->icanon && !tty->canon_data; - old_left = tty->receive_room; - tty->receive_room = left; - - /* Did this open up the receive buffer? We may need to flip */ - if (left && !old_left) - schedule_work(&tty->buf.work); -} - static void put_tty_queue_nolock(unsigned char c, struct tty_struct *tty) { if (tty->read_cnt < N_TTY_BUF_SIZE) { @@ -184,7 +152,6 @@ static void reset_buffer_flags(struct tty_struct *tty) tty->canon_head = tty->canon_data = tty->erasing = 0; memset(&tty->read_flags, 0, sizeof tty->read_flags); - n_tty_set_room(tty); check_unthrottle(tty); } @@ -1360,17 +1327,19 @@ static void n_tty_write_wakeup(struct tty_struct *tty) * calls one at a time and in order (or using flush_to_ldisc) */ -static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, - char *fp, int count) +static unsigned int n_tty_receive_buf(struct tty_struct *tty, + const unsigned char *cp, char *fp, int count) { const unsigned char *p; char *f, flags = TTY_NORMAL; int i; char buf[64]; unsigned long cpuflags; + int left; + int ret = 0; if (!tty->read_buf) - return; + return 0; if (tty->real_raw) { spin_lock_irqsave(&tty->read_lock, cpuflags); @@ -1380,6 +1349,7 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, memcpy(tty->read_buf + tty->read_head, cp, i); tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1); tty->read_cnt += i; + ret += i; cp += i; count -= i; @@ -1389,8 +1359,10 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, memcpy(tty->read_buf + tty->read_head, cp, i); tty->read_head = (tty->read_head + i) & (N_TTY_BUF_SIZE-1); tty->read_cnt += i; + ret += i; spin_unlock_irqrestore(&tty->read_lock, cpuflags); } else { + ret = count; for (i = count, p = cp, f = fp; i; i--, p++) { if (f) flags = *f++; @@ -1418,8 +1390,6 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, tty->ops->flush_chars(tty); } - n_tty_set_room(tty); - if ((!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) || L_EXTPROC(tty)) { kill_fasync(&tty->fasync, SIGIO, POLL_IN); @@ -1432,8 +1402,12 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp, * mode. We don't want to throttle the driver if we're in * canonical mode and don't have a newline yet! */ - if (tty->receive_room < TTY_THRESHOLD_THROTTLE) + left = N_TTY_BUF_SIZE - tty->read_cnt - 1; + + if (left < TTY_THRESHOLD_THROTTLE) tty_throttle(tty); + + return ret; } int is_ignored(int sig) @@ -1477,7 +1451,6 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) if (test_bit(TTY_HW_COOK_IN, &tty->flags)) { tty->raw = 1; tty->real_raw = 1; - n_tty_set_room(tty); return; } if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) || @@ -1530,7 +1503,6 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) else tty->real_raw = 0; } - n_tty_set_room(tty); /* The termios change make the tty ready for I/O */ wake_up_interruptible(&tty->write_wait); wake_up_interruptible(&tty->read_wait); @@ -1812,8 +1784,6 @@ do_it_again: retval = -ERESTARTSYS; break; } - /* FIXME: does n_tty_set_room need locking ? */ - n_tty_set_room(tty); timeout = schedule_timeout(timeout); continue; } @@ -1885,10 +1855,8 @@ do_it_again: * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode, * we won't get any more characters. */ - if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) { - n_tty_set_room(tty); + if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) check_unthrottle(tty); - } if (b - buf >= minimum) break; @@ -1910,7 +1878,6 @@ do_it_again: } else if (test_and_clear_bit(TTY_PUSH, &tty->flags)) goto do_it_again; - n_tty_set_room(tty); return retval; } diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index f1a7918d71aa..46de2e075dac 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -416,6 +416,7 @@ static void flush_to_ldisc(struct work_struct *work) struct tty_buffer *head, *tail = tty->buf.tail; int seen_tail = 0; while ((head = tty->buf.head) != NULL) { + int copied; int count; char *char_buf; unsigned char *flag_buf; @@ -442,17 +443,19 @@ static void flush_to_ldisc(struct work_struct *work) line discipline as we want to empty the queue */ if (test_bit(TTY_FLUSHPENDING, &tty->flags)) break; - if (!tty->receive_room || seen_tail) - break; - if (count > tty->receive_room) - count = tty->receive_room; char_buf = head->char_buf_ptr + head->read; flag_buf = head->flag_buf_ptr + head->read; - head->read += count; spin_unlock_irqrestore(&tty->buf.lock, flags); - disc->ops->receive_buf(tty, char_buf, + copied = disc->ops->receive_buf(tty, char_buf, flag_buf, count); spin_lock_irqsave(&tty->buf.lock, flags); + + head->read += copied; + + if (copied == 0 || seen_tail) { + schedule_work(&tty->buf.work); + break; + } } clear_bit(TTY_FLUSHING, &tty->flags); } diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c index fb864e7fcd13..67b1d0d7c8ac 100644 --- a/drivers/tty/vt/selection.c +++ b/drivers/tty/vt/selection.c @@ -332,8 +332,7 @@ int paste_selection(struct tty_struct *tty) continue; } count = sel_buffer_lth - pasted; - count = min(count, tty->receive_room); - tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted, + count = tty->ldisc->ops->receive_buf(tty, sel_buffer + pasted, NULL, count); pasted += count; } diff --git a/include/linux/tty_ldisc.h b/include/linux/tty_ldisc.h index ff7dc08696a8..5b07792ccb46 100644 --- a/include/linux/tty_ldisc.h +++ b/include/linux/tty_ldisc.h @@ -76,7 +76,7 @@ * tty device. It is solely the responsibility of the line * discipline to handle poll requests. * - * void (*receive_buf)(struct tty_struct *, const unsigned char *cp, + * unsigned int (*receive_buf)(struct tty_struct *, const unsigned char *cp, * char *fp, int count); * * This function is called by the low-level tty driver to send @@ -84,7 +84,8 @@ * processing. is a pointer to the buffer of input * character received by the device. is a pointer to a * pointer of flag bytes which indicate whether a character was - * received with a parity error, etc. + * received with a parity error, etc. Returns the amount of bytes + * received. * * void (*write_wakeup)(struct tty_struct *); * @@ -140,8 +141,8 @@ struct tty_ldisc_ops { /* * The following routines are called from below. */ - void (*receive_buf)(struct tty_struct *, const unsigned char *cp, - char *fp, int count); + unsigned int (*receive_buf)(struct tty_struct *, + const unsigned char *cp, char *fp, int count); void (*write_wakeup)(struct tty_struct *); void (*dcd_change)(struct tty_struct *, unsigned int, struct pps_event_time *); -- cgit v1.3-14-g43fede From 61ec9016988f5c030e96e3c8a42ee9e11b8517aa Mon Sep 17 00:00:00 2001 From: John Linn Date: Sat, 30 Apr 2011 00:07:43 -0400 Subject: tty/serial: add support for Xilinx PS UART The Xilinx PS Uart is used on the new ARM based SoC. This UART is not compatible with others such that a seperate driver is required. Signed-off-by: John Linn Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/Kconfig | 13 + drivers/tty/serial/Makefile | 1 + drivers/tty/serial/xilinx_uartps.c | 1113 ++++++++++++++++++++++++++++++++++++ include/linux/serial_core.h | 3 + 4 files changed, 1130 insertions(+) create mode 100644 drivers/tty/serial/xilinx_uartps.c (limited to 'include/linux') diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig index 80484af781e1..84876ec2ed97 100644 --- a/drivers/tty/serial/Kconfig +++ b/drivers/tty/serial/Kconfig @@ -1612,4 +1612,17 @@ config SERIAL_MXS_AUART_CONSOLE help Enable a MXS AUART port to be the system console. +config SERIAL_XILINX_PS_UART + tristate "Xilinx PS UART support" + select SERIAL_CORE + help + This driver supports the Xilinx PS UART port. + +config SERIAL_XILINX_PS_UART_CONSOLE + bool "Xilinx PS UART console support" + depends on SERIAL_XILINX_PS_UART=y + select SERIAL_CORE_CONSOLE + help + Enable a Xilinx PS UART port to be the system console. + endmenu diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile index fee0690ef8e3..aafddf15992f 100644 --- a/drivers/tty/serial/Makefile +++ b/drivers/tty/serial/Makefile @@ -94,3 +94,4 @@ obj-$(CONFIG_SERIAL_IFX6X60) += ifx6x60.o obj-$(CONFIG_SERIAL_PCH_UART) += pch_uart.o obj-$(CONFIG_SERIAL_MSM_SMD) += msm_smd_tty.o obj-$(CONFIG_SERIAL_MXS_AUART) += mxs-auart.o +obj-$(CONFIG_SERIAL_XILINX_PS_UART) += xilinx_uartps.o diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c new file mode 100644 index 000000000000..19cc1e8149dd --- /dev/null +++ b/drivers/tty/serial/xilinx_uartps.c @@ -0,0 +1,1113 @@ +/* + * Xilinx PS UART driver + * + * 2011 (c) Xilinx Inc. + * + * This program is free software; you can redistribute it + * and/or modify it under the terms of the GNU General Public + * License as published by the Free Software Foundation; + * either version 2 of the License, or (at your option) any + * later version. + * + */ + +#include +#include +#include +#include +#include +#include +#include + +#define XUARTPS_TTY_NAME "ttyPS" +#define XUARTPS_NAME "xuartps" +#define XUARTPS_MAJOR 0 /* use dynamic node allocation */ +#define XUARTPS_MINOR 0 /* works best with devtmpfs */ +#define XUARTPS_NR_PORTS 2 +#define XUARTPS_FIFO_SIZE 16 /* FIFO size */ +#define XUARTPS_REGISTER_SPACE 0xFFF + +#define xuartps_readl(offset) ioread32(port->membase + offset) +#define xuartps_writel(val, offset) iowrite32(val, port->membase + offset) + +/********************************Register Map********************************/ +/** UART + * + * Register offsets for the UART. + * + */ +#define XUARTPS_CR_OFFSET 0x00 /* Control Register [8:0] */ +#define XUARTPS_MR_OFFSET 0x04 /* Mode Register [10:0] */ +#define XUARTPS_IER_OFFSET 0x08 /* Interrupt Enable [10:0] */ +#define XUARTPS_IDR_OFFSET 0x0C /* Interrupt Disable [10:0] */ +#define XUARTPS_IMR_OFFSET 0x10 /* Interrupt Mask [10:0] */ +#define XUARTPS_ISR_OFFSET 0x14 /* Interrupt Status [10:0]*/ +#define XUARTPS_BAUDGEN_OFFSET 0x18 /* Baud Rate Generator [15:0] */ +#define XUARTPS_RXTOUT_OFFSET 0x1C /* RX Timeout [7:0] */ +#define XUARTPS_RXWM_OFFSET 0x20 /* RX FIFO Trigger Level [5:0] */ +#define XUARTPS_MODEMCR_OFFSET 0x24 /* Modem Control [5:0] */ +#define XUARTPS_MODEMSR_OFFSET 0x28 /* Modem Status [8:0] */ +#define XUARTPS_SR_OFFSET 0x2C /* Channel Status [11:0] */ +#define XUARTPS_FIFO_OFFSET 0x30 /* FIFO [15:0] or [7:0] */ +#define XUARTPS_BAUDDIV_OFFSET 0x34 /* Baud Rate Divider [7:0] */ +#define XUARTPS_FLOWDEL_OFFSET 0x38 /* Flow Delay [15:0] */ +#define XUARTPS_IRRX_PWIDTH_OFFSET 0x3C /* IR Minimum Received Pulse + Width [15:0] */ +#define XUARTPS_IRTX_PWIDTH_OFFSET 0x40 /* IR Transmitted pulse + Width [7:0] */ +#define XUARTPS_TXWM_OFFSET 0x44 /* TX FIFO Trigger Level [5:0] */ + +/** Control Register + * + * The Control register (CR) controls the major functions of the device. + * + * Control Register Bit Definitions + */ +#define XUARTPS_CR_STOPBRK 0x00000100 /* Stop TX break */ +#define XUARTPS_CR_STARTBRK 0x00000080 /* Set TX break */ +#define XUARTPS_CR_TX_DIS 0x00000020 /* TX disabled. */ +#define XUARTPS_CR_TX_EN 0x00000010 /* TX enabled */ +#define XUARTPS_CR_RX_DIS 0x00000008 /* RX disabled. */ +#define XUARTPS_CR_RX_EN 0x00000004 /* RX enabled */ +#define XUARTPS_CR_TXRST 0x00000002 /* TX logic reset */ +#define XUARTPS_CR_RXRST 0x00000001 /* RX logic reset */ +#define XUARTPS_CR_RST_TO 0x00000040 /* Restart Timeout Counter */ + +/** Mode Register + * + * The mode register (MR) defines the mode of transfer as well as the data + * format. If this register is modified during transmission or reception, + * data validity cannot be guaranteed. + * + * Mode Register Bit Definitions + * + */ +#define XUARTPS_MR_CLKSEL 0x00000001 /* Pre-scalar selection */ +#define XUARTPS_MR_CHMODE_L_LOOP 0x00000200 /* Local loop back mode */ +#define XUARTPS_MR_CHMODE_NORM 0x00000000 /* Normal mode */ + +#define XUARTPS_MR_STOPMODE_2_BIT 0x00000080 /* 2 stop bits */ +#define XUARTPS_MR_STOPMODE_1_BIT 0x00000000 /* 1 stop bit */ + +#define XUARTPS_MR_PARITY_NONE 0x00000020 /* No parity mode */ +#define XUARTPS_MR_PARITY_MARK 0x00000018 /* Mark parity mode */ +#define XUARTPS_MR_PARITY_SPACE 0x00000010 /* Space parity mode */ +#define XUARTPS_MR_PARITY_ODD 0x00000008 /* Odd parity mode */ +#define XUARTPS_MR_PARITY_EVEN 0x00000000 /* Even parity mode */ + +#define XUARTPS_MR_CHARLEN_6_BIT 0x00000006 /* 6 bits data */ +#define XUARTPS_MR_CHARLEN_7_BIT 0x00000004 /* 7 bits data */ +#define XUARTPS_MR_CHARLEN_8_BIT 0x00000000 /* 8 bits data */ + +/** Interrupt Registers + * + * Interrupt control logic uses the interrupt enable register (IER) and the + * interrupt disable register (IDR) to set the value of the bits in the + * interrupt mask register (IMR). The IMR determines whether to pass an + * interrupt to the interrupt status register (ISR). + * Writing a 1 to IER Enables an interrupt, writing a 1 to IDR disables an + * interrupt. IMR and ISR are read only, and IER and IDR are write only. + * Reading either IER or IDR returns 0x00. + * + * All four registers have the same bit definitions. + */ +#define XUARTPS_IXR_TOUT 0x00000100 /* RX Timeout error interrupt */ +#define XUARTPS_IXR_PARITY 0x00000080 /* Parity error interrupt */ +#define XUARTPS_IXR_FRAMING 0x00000040 /* Framing error interrupt */ +#define XUARTPS_IXR_OVERRUN 0x00000020 /* Overrun error interrupt */ +#define XUARTPS_IXR_TXFULL 0x00000010 /* TX FIFO Full interrupt */ +#define XUARTPS_IXR_TXEMPTY 0x00000008 /* TX FIFO empty interrupt */ +#define XUARTPS_ISR_RXEMPTY 0x00000002 /* RX FIFO empty interrupt */ +#define XUARTPS_IXR_RXTRIG 0x00000001 /* RX FIFO trigger interrupt */ +#define XUARTPS_IXR_RXFULL 0x00000004 /* RX FIFO full interrupt. */ +#define XUARTPS_IXR_RXEMPTY 0x00000002 /* RX FIFO empty interrupt. */ +#define XUARTPS_IXR_MASK 0x00001FFF /* Valid bit mask */ + +/** Channel Status Register + * + * The channel status register (CSR) is provided to enable the control logic + * to monitor the status of bits in the channel interrupt status register, + * even if these are masked out by the interrupt mask register. + */ +#define XUARTPS_SR_RXEMPTY 0x00000002 /* RX FIFO empty */ +#define XUARTPS_SR_TXEMPTY 0x00000008 /* TX FIFO empty */ +#define XUARTPS_SR_TXFULL 0x00000010 /* TX FIFO full */ +#define XUARTPS_SR_RXTRIG 0x00000001 /* Rx Trigger */ + +/** + * xuartps_isr - Interrupt handler + * @irq: Irq number + * @dev_id: Id of the port + * + * Returns IRQHANDLED + **/ +static irqreturn_t xuartps_isr(int irq, void *dev_id) +{ + struct uart_port *port = (struct uart_port *)dev_id; + struct tty_struct *tty; + unsigned long flags; + unsigned int isrstatus, numbytes; + unsigned int data; + char status = TTY_NORMAL; + + /* Get the tty which could be NULL so don't assume it's valid */ + tty = tty_port_tty_get(&port->state->port); + + spin_lock_irqsave(&port->lock, flags); + + /* Read the interrupt status register to determine which + * interrupt(s) is/are active. + */ + isrstatus = xuartps_readl(XUARTPS_ISR_OFFSET); + + /* drop byte with parity error if IGNPAR specified */ + if (isrstatus & port->ignore_status_mask & XUARTPS_IXR_PARITY) + isrstatus &= ~(XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT); + + isrstatus &= port->read_status_mask; + isrstatus &= ~port->ignore_status_mask; + + if ((isrstatus & XUARTPS_IXR_TOUT) || + (isrstatus & XUARTPS_IXR_RXTRIG)) { + /* Receive Timeout Interrupt */ + while ((xuartps_readl(XUARTPS_SR_OFFSET) & + XUARTPS_SR_RXEMPTY) != XUARTPS_SR_RXEMPTY) { + data = xuartps_readl(XUARTPS_FIFO_OFFSET); + port->icount.rx++; + + if (isrstatus & XUARTPS_IXR_PARITY) { + port->icount.parity++; + status = TTY_PARITY; + } else if (isrstatus & XUARTPS_IXR_FRAMING) { + port->icount.frame++; + status = TTY_FRAME; + } else if (isrstatus & XUARTPS_IXR_OVERRUN) + port->icount.overrun++; + + if (tty) + uart_insert_char(port, isrstatus, + XUARTPS_IXR_OVERRUN, data, + status); + } + spin_unlock(&port->lock); + if (tty) + tty_flip_buffer_push(tty); + spin_lock(&port->lock); + } + + /* Dispatch an appropriate handler */ + if ((isrstatus & XUARTPS_IXR_TXEMPTY) == XUARTPS_IXR_TXEMPTY) { + if (uart_circ_empty(&port->state->xmit)) { + xuartps_writel(XUARTPS_IXR_TXEMPTY, + XUARTPS_IDR_OFFSET); + } else { + numbytes = port->fifosize; + /* Break if no more data available in the UART buffer */ + while (numbytes--) { + if (uart_circ_empty(&port->state->xmit)) + break; + /* Get the data from the UART circular buffer + * and write it to the xuartps's TX_FIFO + * register. + */ + xuartps_writel( + port->state->xmit.buf[port->state->xmit. + tail], XUARTPS_FIFO_OFFSET); + + port->icount.tx++; + + /* Adjust the tail of the UART buffer and wrap + * the buffer if it reaches limit. + */ + port->state->xmit.tail = + (port->state->xmit.tail + 1) & \ + (UART_XMIT_SIZE - 1); + } + + if (uart_circ_chars_pending( + &port->state->xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); + } + } + + xuartps_writel(isrstatus, XUARTPS_ISR_OFFSET); + + /* be sure to release the lock and tty before leaving */ + spin_unlock_irqrestore(&port->lock, flags); + tty_kref_put(tty); + + return IRQ_HANDLED; +} + +/** + * xuartps_set_baud_rate - Calculate and set the baud rate + * @port: Handle to the uart port structure + * @baud: Baud rate to set + * + * Returns baud rate, requested baud when possible, or actual baud when there + * was too much error + **/ +static unsigned int xuartps_set_baud_rate(struct uart_port *port, + unsigned int baud) +{ + unsigned int sel_clk; + unsigned int calc_baud = 0; + unsigned int brgr_val, brdiv_val; + unsigned int bauderror; + + /* Formula to obtain baud rate is + * baud_tx/rx rate = sel_clk/CD * (BDIV + 1) + * input_clk = (Uart User Defined Clock or Apb Clock) + * depends on UCLKEN in MR Reg + * sel_clk = input_clk or input_clk/8; + * depends on CLKS in MR reg + * CD and BDIV depends on values in + * baud rate generate register + * baud rate clock divisor register + */ + sel_clk = port->uartclk; + if (xuartps_readl(XUARTPS_MR_OFFSET) & XUARTPS_MR_CLKSEL) + sel_clk = sel_clk / 8; + + /* Find the best values for baud generation */ + for (brdiv_val = 4; brdiv_val < 255; brdiv_val++) { + + brgr_val = sel_clk / (baud * (brdiv_val + 1)); + if (brgr_val < 2 || brgr_val > 65535) + continue; + + calc_baud = sel_clk / (brgr_val * (brdiv_val + 1)); + + if (baud > calc_baud) + bauderror = baud - calc_baud; + else + bauderror = calc_baud - baud; + + /* use the values when percent error is acceptable */ + if (((bauderror * 100) / baud) < 3) { + calc_baud = baud; + break; + } + } + + /* Set the values for the new baud rate */ + xuartps_writel(brgr_val, XUARTPS_BAUDGEN_OFFSET); + xuartps_writel(brdiv_val, XUARTPS_BAUDDIV_OFFSET); + + return calc_baud; +} + +/*----------------------Uart Operations---------------------------*/ + +/** + * xuartps_start_tx - Start transmitting bytes + * @port: Handle to the uart port structure + * + **/ +static void xuartps_start_tx(struct uart_port *port) +{ + unsigned int status, numbytes = port->fifosize; + + if (uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port)) + return; + + status = xuartps_readl(XUARTPS_CR_OFFSET); + /* Set the TX enable bit and clear the TX disable bit to enable the + * transmitter. + */ + xuartps_writel((status & ~XUARTPS_CR_TX_DIS) | XUARTPS_CR_TX_EN, + XUARTPS_CR_OFFSET); + + while (numbytes-- && ((xuartps_readl(XUARTPS_SR_OFFSET) + & XUARTPS_SR_TXFULL)) != XUARTPS_SR_TXFULL) { + + /* Break if no more data available in the UART buffer */ + if (uart_circ_empty(&port->state->xmit)) + break; + + /* Get the data from the UART circular buffer and + * write it to the xuartps's TX_FIFO register. + */ + xuartps_writel( + port->state->xmit.buf[port->state->xmit.tail], + XUARTPS_FIFO_OFFSET); + port->icount.tx++; + + /* Adjust the tail of the UART buffer and wrap + * the buffer if it reaches limit. + */ + port->state->xmit.tail = (port->state->xmit.tail + 1) & + (UART_XMIT_SIZE - 1); + } + + /* Enable the TX Empty interrupt */ + xuartps_writel(XUARTPS_IXR_TXEMPTY, XUARTPS_IER_OFFSET); + + if (uart_circ_chars_pending(&port->state->xmit) < WAKEUP_CHARS) + uart_write_wakeup(port); +} + +/** + * xuartps_stop_tx - Stop TX + * @port: Handle to the uart port structure + * + **/ +static void xuartps_stop_tx(struct uart_port *port) +{ + unsigned int regval; + + regval = xuartps_readl(XUARTPS_CR_OFFSET); + regval |= XUARTPS_CR_TX_DIS; + /* Disable the transmitter */ + xuartps_writel(regval, XUARTPS_CR_OFFSET); +} + +/** + * xuartps_stop_rx - Stop RX + * @port: Handle to the uart port structure + * + **/ +static void xuartps_stop_rx(struct uart_port *port) +{ + unsigned int regval; + + regval = xuartps_readl(XUARTPS_CR_OFFSET); + regval |= XUARTPS_CR_RX_DIS; + /* Disable the receiver */ + xuartps_writel(regval, XUARTPS_CR_OFFSET); +} + +/** + * xuartps_tx_empty - Check whether TX is empty + * @port: Handle to the uart port structure + * + * Returns TIOCSER_TEMT on success, 0 otherwise + **/ +static unsigned int xuartps_tx_empty(struct uart_port *port) +{ + unsigned int status; + + status = xuartps_readl(XUARTPS_ISR_OFFSET) & XUARTPS_IXR_TXEMPTY; + return status ? TIOCSER_TEMT : 0; +} + +/** + * xuartps_break_ctl - Based on the input ctl we have to start or stop + * transmitting char breaks + * @port: Handle to the uart port structure + * @ctl: Value based on which start or stop decision is taken + * + **/ +static void xuartps_break_ctl(struct uart_port *port, int ctl) +{ + unsigned int status; + unsigned long flags; + + spin_lock_irqsave(&port->lock, flags); + + status = xuartps_readl(XUARTPS_CR_OFFSET); + + if (ctl == -1) + xuartps_writel(XUARTPS_CR_STARTBRK | status, + XUARTPS_CR_OFFSET); + else { + if ((status & XUARTPS_CR_STOPBRK) == 0) + xuartps_writel(XUARTPS_CR_STOPBRK | status, + XUARTPS_CR_OFFSET); + } + spin_unlock_irqrestore(&port->lock, flags); +} + +/** + * xuartps_set_termios - termios operations, handling data length, parity, + * stop bits, flow control, baud rate + * @port: Handle to the uart port structure + * @termios: Handle to the input termios structure + * @old: Values of the previously saved termios structure + * + **/ +static void xuartps_set_termios(struct uart_port *port, + struct ktermios *termios, struct ktermios *old) +{ + unsigned int cval = 0; + unsigned int baud; + unsigned long flags; + unsigned int ctrl_reg, mode_reg; + + spin_lock_irqsave(&port->lock, flags); + + /* Empty the receive FIFO 1st before making changes */ + while ((xuartps_readl(XUARTPS_SR_OFFSET) & + XUARTPS_SR_RXEMPTY) != XUARTPS_SR_RXEMPTY) { + xuartps_readl(XUARTPS_FIFO_OFFSET); + } + + /* Disable the TX and RX to set baud rate */ + xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) | + (XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS), + XUARTPS_CR_OFFSET); + + /* Min baud rate = 6bps and Max Baud Rate is 10Mbps for 100Mhz clk */ + baud = uart_get_baud_rate(port, termios, old, 0, 10000000); + baud = xuartps_set_baud_rate(port, baud); + if (tty_termios_baud_rate(termios)) + tty_termios_encode_baud_rate(termios, baud, baud); + + /* + * Update the per-port timeout. + */ + uart_update_timeout(port, termios->c_cflag, baud); + + /* Set TX/RX Reset */ + xuartps_writel(xuartps_readl(XUARTPS_CR_OFFSET) | + (XUARTPS_CR_TXRST | XUARTPS_CR_RXRST), + XUARTPS_CR_OFFSET); + + ctrl_reg = xuartps_readl(XUARTPS_CR_OFFSET); + + /* Clear the RX disable and TX disable bits and then set the TX enable + * bit and RX enable bit to enable the transmitter and receiver. + */ + xuartps_writel( + (ctrl_reg & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) + | (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN), + XUARTPS_CR_OFFSET); + + xuartps_writel(10, XUARTPS_RXTOUT_OFFSET); + + port->read_status_mask = XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_RXTRIG | + XUARTPS_IXR_OVERRUN | XUARTPS_IXR_TOUT; + port->ignore_status_mask = 0; + + if (termios->c_iflag & INPCK) + port->read_status_mask |= XUARTPS_IXR_PARITY | + XUARTPS_IXR_FRAMING; + + if (termios->c_iflag & IGNPAR) + port->ignore_status_mask |= XUARTPS_IXR_PARITY | + XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN; + + /* ignore all characters if CREAD is not set */ + if ((termios->c_cflag & CREAD) == 0) + port->ignore_status_mask |= XUARTPS_IXR_RXTRIG | + XUARTPS_IXR_TOUT | XUARTPS_IXR_PARITY | + XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN; + + mode_reg = xuartps_readl(XUARTPS_MR_OFFSET); + + /* Handling Data Size */ + switch (termios->c_cflag & CSIZE) { + case CS6: + cval |= XUARTPS_MR_CHARLEN_6_BIT; + break; + case CS7: + cval |= XUARTPS_MR_CHARLEN_7_BIT; + break; + default: + case CS8: + cval |= XUARTPS_MR_CHARLEN_8_BIT; + termios->c_cflag &= ~CSIZE; + termios->c_cflag |= CS8; + break; + } + + /* Handling Parity and Stop Bits length */ + if (termios->c_cflag & CSTOPB) + cval |= XUARTPS_MR_STOPMODE_2_BIT; /* 2 STOP bits */ + else + cval |= XUARTPS_MR_STOPMODE_1_BIT; /* 1 STOP bit */ + + if (termios->c_cflag & PARENB) { + /* Mark or Space parity */ + if (termios->c_cflag & CMSPAR) { + if (termios->c_cflag & PARODD) + cval |= XUARTPS_MR_PARITY_MARK; + else + cval |= XUARTPS_MR_PARITY_SPACE; + } else if (termios->c_cflag & PARODD) + cval |= XUARTPS_MR_PARITY_ODD; + else + cval |= XUARTPS_MR_PARITY_EVEN; + } else + cval |= XUARTPS_MR_PARITY_NONE; + xuartps_writel(cval , XUARTPS_MR_OFFSET); + + spin_unlock_irqrestore(&port->lock, flags); +} + +/** + * xuartps_startup - Called when an application opens a xuartps port + * @port: Handle to the uart port structure + * + * Returns 0 on success, negative error otherwise + **/ +static int xuartps_startup(struct uart_port *port) +{ + unsigned int retval = 0, status = 0; + + retval = request_irq(port->irq, xuartps_isr, 0, XUARTPS_NAME, + (void *)port); + if (retval) + return retval; + + /* Disable the TX and RX */ + xuartps_writel(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS, + XUARTPS_CR_OFFSET); + + /* Set the Control Register with TX/RX Enable, TX/RX Reset, + * no break chars. + */ + xuartps_writel(XUARTPS_CR_TXRST | XUARTPS_CR_RXRST, + XUARTPS_CR_OFFSET); + + status = xuartps_readl(XUARTPS_CR_OFFSET); + + /* Clear the RX disable and TX disable bits and then set the TX enable + * bit and RX enable bit to enable the transmitter and receiver. + */ + xuartps_writel((status & ~(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS)) + | (XUARTPS_CR_TX_EN | XUARTPS_CR_RX_EN | + XUARTPS_CR_STOPBRK), XUARTPS_CR_OFFSET); + + /* Set the Mode Register with normal mode,8 data bits,1 stop bit, + * no parity. + */ + xuartps_writel(XUARTPS_MR_CHMODE_NORM | XUARTPS_MR_STOPMODE_1_BIT + | XUARTPS_MR_PARITY_NONE | XUARTPS_MR_CHARLEN_8_BIT, + XUARTPS_MR_OFFSET); + + /* Set the RX FIFO Trigger level to 14 assuming FIFO size as 16 */ + xuartps_writel(14, XUARTPS_RXWM_OFFSET); + + /* Receive Timeout register is enabled with value of 10 */ + xuartps_writel(10, XUARTPS_RXTOUT_OFFSET); + + + /* Set the Interrupt Registers with desired interrupts */ + xuartps_writel(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY | + XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN | + XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT, XUARTPS_IER_OFFSET); + xuartps_writel(~(XUARTPS_IXR_TXEMPTY | XUARTPS_IXR_PARITY | + XUARTPS_IXR_FRAMING | XUARTPS_IXR_OVERRUN | + XUARTPS_IXR_RXTRIG | XUARTPS_IXR_TOUT), XUARTPS_IDR_OFFSET); + + return retval; +} + +/** + * xuartps_shutdown - Called when an application closes a xuartps port + * @port: Handle to the uart port structure + * + **/ +static void xuartps_shutdown(struct uart_port *port) +{ + int status; + + /* Disable interrupts */ + status = xuartps_readl(XUARTPS_IMR_OFFSET); + xuartps_writel(status, XUARTPS_IDR_OFFSET); + + /* Disable the TX and RX */ + xuartps_writel(XUARTPS_CR_TX_DIS | XUARTPS_CR_RX_DIS, + XUARTPS_CR_OFFSET); + free_irq(port->irq, port); +} + +/** + * xuartps_type - Set UART type to xuartps port + * @port: Handle to the uart port structure + * + * Returns string on success, NULL otherwise + **/ +static const char *xuartps_type(struct uart_port *port) +{ + return port->type == PORT_XUARTPS ? XUARTPS_NAME : NULL; +} + +/** + * xuartps_verify_port - Verify the port params + * @port: Handle to the uart port structure + * @ser: Handle to the structure whose members are compared + * + * Returns 0 if success otherwise -EINVAL + **/ +static int xuartps_verify_port(struct uart_port *port, + struct serial_struct *ser) +{ + if (ser->type != PORT_UNKNOWN && ser->type != PORT_XUARTPS) + return -EINVAL; + if (port->irq != ser->irq) + return -EINVAL; + if (ser->io_type != UPIO_MEM) + return -EINVAL; + if (port->iobase != ser->port) + return -EINVAL; + if (ser->hub6 != 0) + return -EINVAL; + return 0; +} + +/** + * xuartps_request_port - Claim the memory region attached to xuartps port, + * called when the driver adds a xuartps port via + * uart_add_one_port() + * @port: Handle to the uart port structure + * + * Returns 0, -ENOMEM if request fails + **/ +static int xuartps_request_port(struct uart_port *port) +{ + if (!request_mem_region(port->mapbase, XUARTPS_REGISTER_SPACE, + XUARTPS_NAME)) { + return -ENOMEM; + } + + port->membase = ioremap(port->mapbase, XUARTPS_REGISTER_SPACE); + if (!port->membase) { + dev_err(port->dev, "Unable to map registers\n"); + release_mem_region(port->mapbase, XUARTPS_REGISTER_SPACE); + return -ENOMEM; + } + return 0; +} + +/** + * xuartps_release_port - Release the memory region attached to a xuartps + * port, called when the driver removes a xuartps + * port via uart_remove_one_port(). + * @port: Handle to the uart port structure + * + **/ +static void xuartps_release_port(struct uart_port *port) +{ + release_mem_region(port->mapbase, XUARTPS_REGISTER_SPACE); + iounmap(port->membase); + port->membase = NULL; +} + +/** + * xuartps_config_port - Configure xuartps, called when the driver adds a + * xuartps port + * @port: Handle to the uart port structure + * @flags: If any + * + **/ +static void xuartps_config_port(struct uart_port *port, int flags) +{ + if (flags & UART_CONFIG_TYPE && xuartps_request_port(port) == 0) + port->type = PORT_XUARTPS; +} + +/** + * xuartps_get_mctrl - Get the modem control state + * + * @port: Handle to the uart port structure + * + * Returns the modem control state + * + **/ +static unsigned int xuartps_get_mctrl(struct uart_port *port) +{ + return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; +} + +static void xuartps_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + /* N/A */ +} + +static void xuartps_enable_ms(struct uart_port *port) +{ + /* N/A */ +} + +/** The UART operations structure + */ +static struct uart_ops xuartps_ops = { + .set_mctrl = xuartps_set_mctrl, + .get_mctrl = xuartps_get_mctrl, + .enable_ms = xuartps_enable_ms, + + .start_tx = xuartps_start_tx, /* Start transmitting */ + .stop_tx = xuartps_stop_tx, /* Stop transmission */ + .stop_rx = xuartps_stop_rx, /* Stop reception */ + .tx_empty = xuartps_tx_empty, /* Transmitter busy? */ + .break_ctl = xuartps_break_ctl, /* Start/stop + * transmitting break + */ + .set_termios = xuartps_set_termios, /* Set termios */ + .startup = xuartps_startup, /* App opens xuartps */ + .shutdown = xuartps_shutdown, /* App closes xuartps */ + .type = xuartps_type, /* Set UART type */ + .verify_port = xuartps_verify_port, /* Verification of port + * params + */ + .request_port = xuartps_request_port, /* Claim resources + * associated with a + * xuartps port + */ + .release_port = xuartps_release_port, /* Release resources + * associated with a + * xuartps port + */ + .config_port = xuartps_config_port, /* Configure when driver + * adds a xuartps port + */ +}; + +static struct uart_port xuartps_port[2]; + +/** + * xuartps_get_port - Configure the port from the platform device resource + * info + * + * Returns a pointer to a uart_port or NULL for failure + **/ +static struct uart_port *xuartps_get_port(void) +{ + struct uart_port *port; + int id; + + /* Find the next unused port */ + for (id = 0; id < XUARTPS_NR_PORTS; id++) + if (xuartps_port[id].mapbase == 0) + break; + + if (id >= XUARTPS_NR_PORTS) + return NULL; + + port = &xuartps_port[id]; + + /* At this point, we've got an empty uart_port struct, initialize it */ + spin_lock_init(&port->lock); + port->membase = NULL; + port->iobase = 1; /* mark port in use */ + port->irq = 0; + port->type = PORT_UNKNOWN; + port->iotype = UPIO_MEM32; + port->flags = UPF_BOOT_AUTOCONF; + port->ops = &xuartps_ops; + port->fifosize = XUARTPS_FIFO_SIZE; + port->line = id; + port->dev = NULL; + return port; +} + +/*-----------------------Console driver operations--------------------------*/ + +#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE +/** + * xuartps_console_wait_tx - Wait for the TX to be full + * @port: Handle to the uart port structure + * + **/ +static void xuartps_console_wait_tx(struct uart_port *port) +{ + while ((xuartps_readl(XUARTPS_SR_OFFSET) & XUARTPS_SR_TXEMPTY) + != XUARTPS_SR_TXEMPTY) + barrier(); +} + +/** + * xuartps_console_putchar - write the character to the FIFO buffer + * @port: Handle to the uart port structure + * @ch: Character to be written + * + **/ +static void xuartps_console_putchar(struct uart_port *port, int ch) +{ + xuartps_console_wait_tx(port); + xuartps_writel(ch, XUARTPS_FIFO_OFFSET); +} + +/** + * xuartps_console_write - perform write operation + * @port: Handle to the uart port structure + * @s: Pointer to character array + * @count: No of characters + **/ +static void xuartps_console_write(struct console *co, const char *s, + unsigned int count) +{ + struct uart_port *port = &xuartps_port[co->index]; + unsigned long flags; + unsigned int imr; + int locked = 1; + + if (oops_in_progress) + locked = spin_trylock_irqsave(&port->lock, flags); + else + spin_lock_irqsave(&port->lock, flags); + + /* save and disable interrupt */ + imr = xuartps_readl(XUARTPS_IMR_OFFSET); + xuartps_writel(imr, XUARTPS_IDR_OFFSET); + + uart_console_write(port, s, count, xuartps_console_putchar); + xuartps_console_wait_tx(port); + + /* restore interrupt state, it seems like there may be a h/w bug + * in that the interrupt enable register should not need to be + * written based on the data sheet + */ + xuartps_writel(~imr, XUARTPS_IDR_OFFSET); + xuartps_writel(imr, XUARTPS_IER_OFFSET); + + if (locked) + spin_unlock_irqrestore(&port->lock, flags); +} + +/** + * xuartps_console_setup - Initialize the uart to default config + * @co: Console handle + * @options: Initial settings of uart + * + * Returns 0, -ENODEV if no device + **/ +static int __init xuartps_console_setup(struct console *co, char *options) +{ + struct uart_port *port = &xuartps_port[co->index]; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + if (co->index < 0 || co->index >= XUARTPS_NR_PORTS) + return -EINVAL; + + if (!port->mapbase) { + pr_debug("console on ttyPS%i not present\n", co->index); + return -ENODEV; + } + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + + return uart_set_options(port, co, baud, parity, bits, flow); +} + +static struct uart_driver xuartps_uart_driver; + +static struct console xuartps_console = { + .name = XUARTPS_TTY_NAME, + .write = xuartps_console_write, + .device = uart_console_device, + .setup = xuartps_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, /* Specified on the cmdline (e.g. console=ttyPS ) */ + .data = &xuartps_uart_driver, +}; + +/** + * xuartps_console_init - Initialization call + * + * Returns 0 on success, negative error otherwise + **/ +static int __init xuartps_console_init(void) +{ + register_console(&xuartps_console); + return 0; +} + +console_initcall(xuartps_console_init); + +#endif /* CONFIG_SERIAL_XILINX_PS_UART_CONSOLE */ + +/** Structure Definitions + */ +static struct uart_driver xuartps_uart_driver = { + .owner = THIS_MODULE, /* Owner */ + .driver_name = XUARTPS_NAME, /* Driver name */ + .dev_name = XUARTPS_TTY_NAME, /* Node name */ + .major = XUARTPS_MAJOR, /* Major number */ + .minor = XUARTPS_MINOR, /* Minor number */ + .nr = XUARTPS_NR_PORTS, /* Number of UART ports */ +#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE + .cons = &xuartps_console, /* Console */ +#endif +}; + +/* --------------------------------------------------------------------- + * Platform bus binding + */ +/** + * xuartps_probe - Platform driver probe + * @pdev: Pointer to the platform device structure + * + * Returns 0 on success, negative error otherwise + **/ +static int __devinit xuartps_probe(struct platform_device *pdev) +{ + int rc; + struct uart_port *port; + struct resource *res, *res2; + int clk = 0; + +#ifdef CONFIG_OF + const unsigned int *prop; + + prop = of_get_property(pdev->dev.of_node, "clock", NULL); + if (prop) + clk = be32_to_cpup(prop); +#else + clk = *((unsigned int *)(pdev->dev.platform_data)); +#endif + if (!clk) { + dev_err(&pdev->dev, "no clock specified\n"); + return -ENODEV; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (!res2) + return -ENODEV; + + /* Initialize the port structure */ + port = xuartps_get_port(); + + if (!port) { + dev_err(&pdev->dev, "Cannot get uart_port structure\n"); + return -ENODEV; + } else { + /* Register the port. + * This function also registers this device with the tty layer + * and triggers invocation of the config_port() entry point. + */ + port->mapbase = res->start; + port->irq = res2->start; + port->dev = &pdev->dev; + port->uartclk = clk; + dev_set_drvdata(&pdev->dev, port); + rc = uart_add_one_port(&xuartps_uart_driver, port); + if (rc) { + dev_err(&pdev->dev, + "uart_add_one_port() failed; err=%i\n", rc); + dev_set_drvdata(&pdev->dev, NULL); + return rc; + } + return 0; + } +} + +/** + * xuartps_remove - called when the platform driver is unregistered + * @pdev: Pointer to the platform device structure + * + * Returns 0 on success, negative error otherwise + **/ +static int __devexit xuartps_remove(struct platform_device *pdev) +{ + struct uart_port *port = dev_get_drvdata(&pdev->dev); + int rc = 0; + + /* Remove the xuartps port from the serial core */ + if (port) { + rc = uart_remove_one_port(&xuartps_uart_driver, port); + dev_set_drvdata(&pdev->dev, NULL); + port->mapbase = 0; + } + return rc; +} + +/** + * xuartps_suspend - suspend event + * @pdev: Pointer to the platform device structure + * @state: State of the device + * + * Returns 0 + **/ +static int xuartps_suspend(struct platform_device *pdev, pm_message_t state) +{ + /* Call the API provided in serial_core.c file which handles + * the suspend. + */ + uart_suspend_port(&xuartps_uart_driver, &xuartps_port[pdev->id]); + return 0; +} + +/** + * xuartps_resume - Resume after a previous suspend + * @pdev: Pointer to the platform device structure + * + * Returns 0 + **/ +static int xuartps_resume(struct platform_device *pdev) +{ + uart_resume_port(&xuartps_uart_driver, &xuartps_port[pdev->id]); + return 0; +} + +/* Match table for of_platform binding */ + +#ifdef CONFIG_OF +static struct of_device_id xuartps_of_match[] __devinitdata = { + { .compatible = "xlnx,xuartps", }, + {} +}; +MODULE_DEVICE_TABLE(of, xuartps_of_match); +#else +#define xuartps_of_match NULL +#endif + +static struct platform_driver xuartps_platform_driver = { + .probe = xuartps_probe, /* Probe method */ + .remove = __exit_p(xuartps_remove), /* Detach method */ + .suspend = xuartps_suspend, /* Suspend */ + .resume = xuartps_resume, /* Resume after a suspend */ + .driver = { + .owner = THIS_MODULE, + .name = XUARTPS_NAME, /* Driver name */ + .of_match_table = xuartps_of_match, + }, +}; + +/* --------------------------------------------------------------------- + * Module Init and Exit + */ +/** + * xuartps_init - Initial driver registration call + * + * Returns whether the registration was successful or not + **/ +static int __init xuartps_init(void) +{ + int retval = 0; + + /* Register the xuartps driver with the serial core */ + retval = uart_register_driver(&xuartps_uart_driver); + if (retval) + return retval; + + /* Register the platform driver */ + retval = platform_driver_register(&xuartps_platform_driver); + if (retval) + uart_unregister_driver(&xuartps_uart_driver); + + return retval; +} + +/** + * xuartps_exit - Driver unregistration call + **/ +static void __exit xuartps_exit(void) +{ + /* The order of unregistration is important. Unregister the + * UART driver before the platform driver crashes the system. + */ + + /* Unregister the platform driver */ + platform_driver_unregister(&xuartps_platform_driver); + + /* Unregister the xuartps driver */ + uart_unregister_driver(&xuartps_uart_driver); +} + +module_init(xuartps_init); +module_exit(xuartps_exit); + +MODULE_DESCRIPTION("Driver for PS UART"); +MODULE_AUTHOR("Xilinx Inc."); +MODULE_LICENSE("GPL"); diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 758c5b0c6fd3..95d479ba514e 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -202,6 +202,9 @@ /* VIA VT8500 SoC */ #define PORT_VT8500 97 +/* Xilinx PSS UART */ +#define PORT_XUARTPS 98 + #ifdef __KERNEL__ #include -- cgit v1.3-14-g43fede From 0b61d2acb1ea48d8eba798ed92759b7f1b0f4209 Mon Sep 17 00:00:00 2001 From: J Freyensee Date: Fri, 6 May 2011 16:56:49 -0700 Subject: Intel PTI implementaiton of MIPI 1149.7. The PTI (Parallel Trace Interface) driver directs trace data routed from various parts in the system out through an Intel Penwell PTI port and out of the mobile device for analysis with a debugging tool (Lauterbach or Fido). Though n_tracesink and n_tracerouter line discipline drivers are used to extract modem tracing data to the PTI driver and other parts of an Intel mobile solution, the PTI driver can be used independent of n_tracesink and n_tracerouter. You should select this driver if the target kernel is meant for an Intel Atom (non-netbook) mobile device containing a MIPI P1149.7 standard implementation. Signed-off-by: J Freyensee Signed-off-by: Greg Kroah-Hartman --- drivers/misc/Kconfig | 13 + drivers/misc/Makefile | 1 + drivers/misc/pti.c | 980 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/pti.h | 42 +++ 4 files changed, 1036 insertions(+) create mode 100644 drivers/misc/pti.c create mode 100644 include/linux/pti.h (limited to 'include/linux') diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 915c31ef84cd..ec33d939548c 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -144,6 +144,19 @@ config PHANTOM If you choose to build module, its name will be phantom. If unsure, say N here. +config INTEL_MID_PTI + tristate "Parallel Trace Interface for MIPI P1149.7 cJTAG standard" + default n + help + The PTI (Parallel Trace Interface) driver directs + trace data routed from various parts in the system out + through an Intel Penwell PTI port and out of the mobile + device for analysis with a debugging tool (Lauterbach or Fido). + + You should select this driver if the target kernel is meant for + an Intel Atom (non-netbook) mobile device containing a MIPI + P1149.7 standard implementation. + config SGI_IOC4 tristate "SGI IOC4 Base IO support" depends on PCI diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index f5468602961f..662aa3c71d05 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_IBM_ASM) += ibmasm/ obj-$(CONFIG_AD525X_DPOT) += ad525x_dpot.o obj-$(CONFIG_AD525X_DPOT_I2C) += ad525x_dpot-i2c.o obj-$(CONFIG_AD525X_DPOT_SPI) += ad525x_dpot-spi.o +0bj-$(CONFIG_INTEL_MID_PTI) += pti.o obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o diff --git a/drivers/misc/pti.c b/drivers/misc/pti.c new file mode 100644 index 000000000000..bb6f9255c17c --- /dev/null +++ b/drivers/misc/pti.c @@ -0,0 +1,980 @@ +/* + * pti.c - PTI driver for cJTAG data extration + * + * Copyright (C) Intel 2010 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * The PTI (Parallel Trace Interface) driver directs trace data routed from + * various parts in the system out through the Intel Penwell PTI port and + * out of the mobile device for analysis with a debugging tool + * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7, + * compact JTAG, standard. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define DRIVERNAME "pti" +#define PCINAME "pciPTI" +#define TTYNAME "ttyPTI" +#define CHARNAME "pti" +#define PTITTY_MINOR_START 0 +#define PTITTY_MINOR_NUM 2 +#define MAX_APP_IDS 16 /* 128 channel ids / u8 bit size */ +#define MAX_OS_IDS 16 /* 128 channel ids / u8 bit size */ +#define MAX_MODEM_IDS 16 /* 128 channel ids / u8 bit size */ +#define MODEM_BASE_ID 71 /* modem master ID address */ +#define CONTROL_ID 72 /* control master ID address */ +#define CONSOLE_ID 73 /* console master ID address */ +#define OS_BASE_ID 74 /* base OS master ID address */ +#define APP_BASE_ID 80 /* base App master ID address */ +#define CONTROL_FRAME_LEN 32 /* PTI control frame maximum size */ +#define USER_COPY_SIZE 8192 /* 8Kb buffer for user space copy */ +#define APERTURE_14 0x3800000 /* offset to first OS write addr */ +#define APERTURE_LEN 0x400000 /* address length */ + +struct pti_tty { + struct pti_masterchannel *mc; +}; + +struct pti_dev { + struct tty_port port; + unsigned long pti_addr; + unsigned long aperture_base; + void __iomem *pti_ioaddr; + u8 ia_app[MAX_APP_IDS]; + u8 ia_os[MAX_OS_IDS]; + u8 ia_modem[MAX_MODEM_IDS]; +}; + +/* + * This protects access to ia_app, ia_os, and ia_modem, + * which keeps track of channels allocated in + * an aperture write id. + */ +static DEFINE_MUTEX(alloclock); + +static struct pci_device_id pci_ids[] __devinitconst = { + {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x82B)}, + {0} +}; + +static struct tty_driver *pti_tty_driver; +static struct pti_dev *drv_data; + +static unsigned int pti_console_channel; +static unsigned int pti_control_channel; + +/** + * pti_write_to_aperture()- The private write function to PTI HW. + * + * @mc: The 'aperture'. It's part of a write address that holds + * a master and channel ID. + * @buf: Data being written to the HW that will ultimately be seen + * in a debugging tool (Fido, Lauterbach). + * @len: Size of buffer. + * + * Since each aperture is specified by a unique + * master/channel ID, no two processes will be writing + * to the same aperture at the same time so no lock is required. The + * PTI-Output agent will send these out in the order that they arrived, and + * thus, it will intermix these messages. The debug tool can then later + * regroup the appropriate message segments together reconstituting each + * message. + */ +static void pti_write_to_aperture(struct pti_masterchannel *mc, + u8 *buf, + int len) +{ + int dwordcnt; + int final; + int i; + u32 ptiword; + u32 __iomem *aperture; + u8 *p = buf; + + /* + * calculate the aperture offset from the base using the master and + * channel id's. + */ + aperture = drv_data->pti_ioaddr + (mc->master << 15) + + (mc->channel << 8); + + dwordcnt = len >> 2; + final = len - (dwordcnt << 2); /* final = trailing bytes */ + if (final == 0 && dwordcnt != 0) { /* always need a final dword */ + final += 4; + dwordcnt--; + } + + for (i = 0; i < dwordcnt; i++) { + ptiword = be32_to_cpu(*(u32 *)p); + p += 4; + iowrite32(ptiword, aperture); + } + + aperture += PTI_LASTDWORD_DTS; /* adding DTS signals that is EOM */ + + ptiword = 0; + for (i = 0; i < final; i++) + ptiword |= *p++ << (24-(8*i)); + + iowrite32(ptiword, aperture); + return; +} + +/** + * pti_control_frame_built_and_sent()- control frame build and send function. + * + * @mc: The master / channel structure on which the function + * built a control frame. + * + * To be able to post process the PTI contents on host side, a control frame + * is added before sending any PTI content. So the host side knows on + * each PTI frame the name of the thread using a dedicated master / channel. + * The thread name is retrieved from the 'current' global variable. + * This function builds this frame and sends it to a master ID CONTROL_ID. + * The overhead is only 32 bytes since the driver only writes to HW + * in 32 byte chunks. + */ + +static void pti_control_frame_built_and_sent(struct pti_masterchannel *mc) +{ + struct pti_masterchannel mccontrol = {.master = CONTROL_ID, + .channel = 0}; + const char *control_format = "%3d %3d %s"; + u8 control_frame[CONTROL_FRAME_LEN]; + + /* + * Since we access the comm member in current's task_struct, + * we only need to be as large as what 'comm' in that + * structure is. + */ + char comm[TASK_COMM_LEN]; + + if (!in_interrupt()) + get_task_comm(comm, current); + else + strncpy(comm, "Interrupt", TASK_COMM_LEN); + + /* Absolutely ensure our buffer is zero terminated. */ + comm[TASK_COMM_LEN-1] = 0; + + mccontrol.channel = pti_control_channel; + pti_control_channel = (pti_control_channel + 1) & 0x7f; + + snprintf(control_frame, CONTROL_FRAME_LEN, control_format, mc->master, + mc->channel, comm); + pti_write_to_aperture(&mccontrol, control_frame, strlen(control_frame)); +} + +/** + * pti_write_full_frame_to_aperture()- high level function to + * write to PTI. + * + * @mc: The 'aperture'. It's part of a write address that holds + * a master and channel ID. + * @buf: Data being written to the HW that will ultimately be seen + * in a debugging tool (Fido, Lauterbach). + * @len: Size of buffer. + * + * All threads sending data (either console, user space application, ...) + * are calling the high level function to write to PTI meaning that it is + * possible to add a control frame before sending the content. + */ +static void pti_write_full_frame_to_aperture(struct pti_masterchannel *mc, + const unsigned char *buf, + int len) +{ + pti_control_frame_built_and_sent(mc); + pti_write_to_aperture(mc, (u8 *)buf, len); +} + +/** + * get_id()- Allocate a master and channel ID. + * + * @id_array: an array of bits representing what channel + * id's are allocated for writing. + * @max_ids: The max amount of available write IDs to use. + * @base_id: The starting SW channel ID, based on the Intel + * PTI arch. + * + * Returns: + * pti_masterchannel struct with master, channel ID address + * 0 for error + * + * Each bit in the arrays ia_app and ia_os correspond to a master and + * channel id. The bit is one if the id is taken and 0 if free. For + * every master there are 128 channel id's. + */ +static struct pti_masterchannel *get_id(u8 *id_array, int max_ids, int base_id) +{ + struct pti_masterchannel *mc; + int i, j, mask; + + mc = kmalloc(sizeof(struct pti_masterchannel), GFP_KERNEL); + if (mc == NULL) + return NULL; + + /* look for a byte with a free bit */ + for (i = 0; i < max_ids; i++) + if (id_array[i] != 0xff) + break; + if (i == max_ids) { + kfree(mc); + return NULL; + } + /* find the bit in the 128 possible channel opportunities */ + mask = 0x80; + for (j = 0; j < 8; j++) { + if ((id_array[i] & mask) == 0) + break; + mask >>= 1; + } + + /* grab it */ + id_array[i] |= mask; + mc->master = base_id; + mc->channel = ((i & 0xf)<<3) + j; + /* write new master Id / channel Id allocation to channel control */ + pti_control_frame_built_and_sent(mc); + return mc; +} + +/* + * The following three functions: + * pti_request_mastercahannel(), mipi_release_masterchannel() + * and pti_writedata() are an API for other kernel drivers to + * access PTI. + */ + +/** + * pti_request_masterchannel()- Kernel API function used to allocate + * a master, channel ID address + * to write to PTI HW. + * + * @type: 0- request Application master, channel aperture ID write address. + * 1- request OS master, channel aperture ID write + * address. + * 2- request Modem master, channel aperture ID + * write address. + * Other values, error. + * + * Returns: + * pti_masterchannel struct + * 0 for error + */ +struct pti_masterchannel *pti_request_masterchannel(u8 type) +{ + struct pti_masterchannel *mc; + + mutex_lock(&alloclock); + + switch (type) { + + case 0: + mc = get_id(drv_data->ia_app, MAX_APP_IDS, APP_BASE_ID); + break; + + case 1: + mc = get_id(drv_data->ia_os, MAX_OS_IDS, OS_BASE_ID); + break; + + case 2: + mc = get_id(drv_data->ia_modem, MAX_MODEM_IDS, MODEM_BASE_ID); + break; + default: + mc = NULL; + } + + mutex_unlock(&alloclock); + return mc; +} +EXPORT_SYMBOL_GPL(pti_request_masterchannel); + +/** + * pti_release_masterchannel()- Kernel API function used to release + * a master, channel ID address + * used to write to PTI HW. + * + * @mc: master, channel apeture ID address to be released. + */ +void pti_release_masterchannel(struct pti_masterchannel *mc) +{ + u8 master, channel, i; + + mutex_lock(&alloclock); + + if (mc) { + master = mc->master; + channel = mc->channel; + + if (master == APP_BASE_ID) { + i = channel >> 3; + drv_data->ia_app[i] &= ~(0x80>>(channel & 0x7)); + } else if (master == OS_BASE_ID) { + i = channel >> 3; + drv_data->ia_os[i] &= ~(0x80>>(channel & 0x7)); + } else { + i = channel >> 3; + drv_data->ia_modem[i] &= ~(0x80>>(channel & 0x7)); + } + + kfree(mc); + } + + mutex_unlock(&alloclock); +} +EXPORT_SYMBOL_GPL(pti_release_masterchannel); + +/** + * pti_writedata()- Kernel API function used to write trace + * debugging data to PTI HW. + * + * @mc: Master, channel aperture ID address to write to. + * Null value will return with no write occurring. + * @buf: Trace debuging data to write to the PTI HW. + * Null value will return with no write occurring. + * @count: Size of buf. Value of 0 or a negative number will + * return with no write occuring. + */ +void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count) +{ + /* + * since this function is exported, this is treated like an + * API function, thus, all parameters should + * be checked for validity. + */ + if ((mc != NULL) && (buf != NULL) && (count > 0)) + pti_write_to_aperture(mc, buf, count); + return; +} +EXPORT_SYMBOL_GPL(pti_writedata); + +/** + * pti_pci_remove()- Driver exit method to remove PTI from + * PCI bus. + * @pdev: variable containing pci info of PTI. + */ +static void __devexit pti_pci_remove(struct pci_dev *pdev) +{ + struct pti_dev *drv_data; + + drv_data = pci_get_drvdata(pdev); + if (drv_data != NULL) { + pci_iounmap(pdev, drv_data->pti_ioaddr); + pci_set_drvdata(pdev, NULL); + kfree(drv_data); + pci_release_region(pdev, 1); + pci_disable_device(pdev); + } +} + +/* + * for the tty_driver_*() basic function descriptions, see tty_driver.h. + * Specific header comments made for PTI-related specifics. + */ + +/** + * pti_tty_driver_open()- Open an Application master, channel aperture + * ID to the PTI device via tty device. + * + * @tty: tty interface. + * @filp: filp interface pased to tty_port_open() call. + * + * Returns: + * int, 0 for success + * otherwise, fail value + * + * The main purpose of using the tty device interface is for + * each tty port to have a unique PTI write aperture. In an + * example use case, ttyPTI0 gets syslogd and an APP aperture + * ID and ttyPTI1 is where the n_tracesink ldisc hooks to route + * modem messages into PTI. Modem trace data does not have to + * go to ttyPTI1, but ttyPTI0 and ttyPTI1 do need to be distinct + * master IDs. These messages go through the PTI HW and out of + * the handheld platform and to the Fido/Lauterbach device. + */ +static int pti_tty_driver_open(struct tty_struct *tty, struct file *filp) +{ + /* + * we actually want to allocate a new channel per open, per + * system arch. HW gives more than plenty channels for a single + * system task to have its own channel to write trace data. This + * also removes a locking requirement for the actual write + * procedure. + */ + return tty_port_open(&drv_data->port, tty, filp); +} + +/** + * pti_tty_driver_close()- close tty device and release Application + * master, channel aperture ID to the PTI device via tty device. + * + * @tty: tty interface. + * @filp: filp interface pased to tty_port_close() call. + * + * The main purpose of using the tty device interface is to route + * syslog daemon messages to the PTI HW and out of the handheld platform + * and to the Fido/Lauterbach device. + */ +static void pti_tty_driver_close(struct tty_struct *tty, struct file *filp) +{ + tty_port_close(&drv_data->port, tty, filp); +} + +/** + * pti_tty_intstall()- Used to set up specific master-channels + * to tty ports for organizational purposes when + * tracing viewed from debuging tools. + * + * @driver: tty driver information. + * @tty: tty struct containing pti information. + * + * Returns: + * 0 for success + * otherwise, error + */ +static int pti_tty_install(struct tty_driver *driver, struct tty_struct *tty) +{ + int idx = tty->index; + struct pti_tty *pti_tty_data; + int ret = tty_init_termios(tty); + + if (ret == 0) { + tty_driver_kref_get(driver); + tty->count++; + driver->ttys[idx] = tty; + + pti_tty_data = kmalloc(sizeof(struct pti_tty), GFP_KERNEL); + if (pti_tty_data == NULL) + return -ENOMEM; + + if (idx == PTITTY_MINOR_START) + pti_tty_data->mc = pti_request_masterchannel(0); + else + pti_tty_data->mc = pti_request_masterchannel(2); + + if (pti_tty_data->mc == NULL) + return -ENXIO; + tty->driver_data = pti_tty_data; + } + + return ret; +} + +/** + * pti_tty_cleanup()- Used to de-allocate master-channel resources + * tied to tty's of this driver. + * + * @tty: tty struct containing pti information. + */ +static void pti_tty_cleanup(struct tty_struct *tty) +{ + struct pti_tty *pti_tty_data = tty->driver_data; + if (pti_tty_data == NULL) + return; + pti_release_masterchannel(pti_tty_data->mc); + kfree(tty->driver_data); + tty->driver_data = NULL; +} + +/** + * pti_tty_driver_write()- Write trace debugging data through the char + * interface to the PTI HW. Part of the misc device implementation. + * + * @filp: Contains private data which is used to obtain + * master, channel write ID. + * @data: trace data to be written. + * @len: # of byte to write. + * + * Returns: + * int, # of bytes written + * otherwise, error + */ +static int pti_tty_driver_write(struct tty_struct *tty, + const unsigned char *buf, int len) +{ + struct pti_tty *pti_tty_data = tty->driver_data; + if ((pti_tty_data != NULL) && (pti_tty_data->mc != NULL)) { + pti_write_to_aperture(pti_tty_data->mc, (u8 *)buf, len); + return len; + } + /* + * we can't write to the pti hardware if the private driver_data + * and the mc address is not there. + */ + else + return -EFAULT; +} + +/** + * pti_tty_write_room()- Always returns 2048. + * + * @tty: contains tty info of the pti driver. + */ +static int pti_tty_write_room(struct tty_struct *tty) +{ + return 2048; +} + +/** + * pti_char_open()- Open an Application master, channel aperture + * ID to the PTI device. Part of the misc device implementation. + * + * @inode: not used. + * @filp: Output- will have a masterchannel struct set containing + * the allocated application PTI aperture write address. + * + * Returns: + * int, 0 for success + * otherwise, a fail value + */ +static int pti_char_open(struct inode *inode, struct file *filp) +{ + struct pti_masterchannel *mc; + + /* + * We really do want to fail immediately if + * pti_request_masterchannel() fails, + * before assigning the value to filp->private_data. + * Slightly easier to debug if this driver needs debugging. + */ + mc = pti_request_masterchannel(0); + if (mc == NULL) + return -ENOMEM; + filp->private_data = mc; + return 0; +} + +/** + * pti_char_release()- Close a char channel to the PTI device. Part + * of the misc device implementation. + * + * @inode: Not used in this implementaiton. + * @filp: Contains private_data that contains the master, channel + * ID to be released by the PTI device. + * + * Returns: + * always 0 + */ +static int pti_char_release(struct inode *inode, struct file *filp) +{ + pti_release_masterchannel(filp->private_data); + kfree(filp->private_data); + return 0; +} + +/** + * pti_char_write()- Write trace debugging data through the char + * interface to the PTI HW. Part of the misc device implementation. + * + * @filp: Contains private data which is used to obtain + * master, channel write ID. + * @data: trace data to be written. + * @len: # of byte to write. + * @ppose: Not used in this function implementation. + * + * Returns: + * int, # of bytes written + * otherwise, error value + * + * Notes: From side discussions with Alan Cox and experimenting + * with PTI debug HW like Nokia's Fido box and Lauterbach + * devices, 8192 byte write buffer used by USER_COPY_SIZE was + * deemed an appropriate size for this type of usage with + * debugging HW. + */ +static ssize_t pti_char_write(struct file *filp, const char __user *data, + size_t len, loff_t *ppose) +{ + struct pti_masterchannel *mc; + void *kbuf; + const char __user *tmp; + size_t size = USER_COPY_SIZE; + size_t n = 0; + + tmp = data; + mc = filp->private_data; + + kbuf = kmalloc(size, GFP_KERNEL); + if (kbuf == NULL) { + pr_err("%s(%d): buf allocation failed\n", + __func__, __LINE__); + return -ENOMEM; + } + + do { + if (len - n > USER_COPY_SIZE) + size = USER_COPY_SIZE; + else + size = len - n; + + if (copy_from_user(kbuf, tmp, size)) { + kfree(kbuf); + return n ? n : -EFAULT; + } + + pti_write_to_aperture(mc, kbuf, size); + n += size; + tmp += size; + + } while (len > n); + + kfree(kbuf); + return len; +} + +static const struct tty_operations pti_tty_driver_ops = { + .open = pti_tty_driver_open, + .close = pti_tty_driver_close, + .write = pti_tty_driver_write, + .write_room = pti_tty_write_room, + .install = pti_tty_install, + .cleanup = pti_tty_cleanup +}; + +static const struct file_operations pti_char_driver_ops = { + .owner = THIS_MODULE, + .write = pti_char_write, + .open = pti_char_open, + .release = pti_char_release, +}; + +static struct miscdevice pti_char_driver = { + .minor = MISC_DYNAMIC_MINOR, + .name = CHARNAME, + .fops = &pti_char_driver_ops +}; + +/** + * pti_console_write()- Write to the console that has been acquired. + * + * @c: Not used in this implementaiton. + * @buf: Data to be written. + * @len: Length of buf. + */ +static void pti_console_write(struct console *c, const char *buf, unsigned len) +{ + static struct pti_masterchannel mc = {.master = CONSOLE_ID, + .channel = 0}; + + mc.channel = pti_console_channel; + pti_console_channel = (pti_console_channel + 1) & 0x7f; + + pti_write_full_frame_to_aperture(&mc, buf, len); +} + +/** + * pti_console_device()- Return the driver tty structure and set the + * associated index implementation. + * + * @c: Console device of the driver. + * @index: index associated with c. + * + * Returns: + * always value of pti_tty_driver structure when this function + * is called. + */ +static struct tty_driver *pti_console_device(struct console *c, int *index) +{ + *index = c->index; + return pti_tty_driver; +} + +/** + * pti_console_setup()- Initialize console variables used by the driver. + * + * @c: Not used. + * @opts: Not used. + * + * Returns: + * always 0. + */ +static int pti_console_setup(struct console *c, char *opts) +{ + pti_console_channel = 0; + pti_control_channel = 0; + return 0; +} + +/* + * pti_console struct, used to capture OS printk()'s and shift + * out to the PTI device for debugging. This cannot be + * enabled upon boot because of the possibility of eating + * any serial console printk's (race condition discovered). + * The console should be enabled upon when the tty port is + * used for the first time. Since the primary purpose for + * the tty port is to hook up syslog to it, the tty port + * will be open for a really long time. + */ +static struct console pti_console = { + .name = TTYNAME, + .write = pti_console_write, + .device = pti_console_device, + .setup = pti_console_setup, + .flags = CON_PRINTBUFFER, + .index = 0, +}; + +/** + * pti_port_activate()- Used to start/initialize any items upon + * first opening of tty_port(). + * + * @port- The tty port number of the PTI device. + * @tty- The tty struct associated with this device. + * + * Returns: + * always returns 0 + * + * Notes: The primary purpose of the PTI tty port 0 is to hook + * the syslog daemon to it; thus this port will be open for a + * very long time. + */ +static int pti_port_activate(struct tty_port *port, struct tty_struct *tty) +{ + if (port->tty->index == PTITTY_MINOR_START) + console_start(&pti_console); + return 0; +} + +/** + * pti_port_shutdown()- Used to stop/shutdown any items upon the + * last tty port close. + * + * @port- The tty port number of the PTI device. + * + * Notes: The primary purpose of the PTI tty port 0 is to hook + * the syslog daemon to it; thus this port will be open for a + * very long time. + */ +static void pti_port_shutdown(struct tty_port *port) +{ + if (port->tty->index == PTITTY_MINOR_START) + console_stop(&pti_console); +} + +static const struct tty_port_operations tty_port_ops = { + .activate = pti_port_activate, + .shutdown = pti_port_shutdown, +}; + +/* + * Note the _probe() call sets everything up and ties the char and tty + * to successfully detecting the PTI device on the pci bus. + */ + +/** + * pti_pci_probe()- Used to detect pti on the pci bus and set + * things up in the driver. + * + * @pdev- pci_dev struct values for pti. + * @ent- pci_device_id struct for pti driver. + * + * Returns: + * 0 for success + * otherwise, error + */ +static int __devinit pti_pci_probe(struct pci_dev *pdev, + const struct pci_device_id *ent) +{ + int retval = -EINVAL; + int pci_bar = 1; + + dev_dbg(&pdev->dev, "%s %s(%d): PTI PCI ID %04x:%04x\n", __FILE__, + __func__, __LINE__, pdev->vendor, pdev->device); + + retval = misc_register(&pti_char_driver); + if (retval) { + pr_err("%s(%d): CHAR registration failed of pti driver\n", + __func__, __LINE__); + pr_err("%s(%d): Error value returned: %d\n", + __func__, __LINE__, retval); + return retval; + } + + retval = pci_enable_device(pdev); + if (retval != 0) { + dev_err(&pdev->dev, + "%s: pci_enable_device() returned error %d\n", + __func__, retval); + return retval; + } + + drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL); + + if (drv_data == NULL) { + retval = -ENOMEM; + dev_err(&pdev->dev, + "%s(%d): kmalloc() returned NULL memory.\n", + __func__, __LINE__); + return retval; + } + drv_data->pti_addr = pci_resource_start(pdev, pci_bar); + + retval = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev)); + if (retval != 0) { + dev_err(&pdev->dev, + "%s(%d): pci_request_region() returned error %d\n", + __func__, __LINE__, retval); + kfree(drv_data); + return retval; + } + drv_data->aperture_base = drv_data->pti_addr+APERTURE_14; + drv_data->pti_ioaddr = + ioremap_nocache((u32)drv_data->aperture_base, + APERTURE_LEN); + if (!drv_data->pti_ioaddr) { + pci_release_region(pdev, pci_bar); + retval = -ENOMEM; + kfree(drv_data); + return retval; + } + + pci_set_drvdata(pdev, drv_data); + + tty_port_init(&drv_data->port); + drv_data->port.ops = &tty_port_ops; + + tty_register_device(pti_tty_driver, 0, &pdev->dev); + tty_register_device(pti_tty_driver, 1, &pdev->dev); + + register_console(&pti_console); + + return retval; +} + +static struct pci_driver pti_pci_driver = { + .name = PCINAME, + .id_table = pci_ids, + .probe = pti_pci_probe, + .remove = pti_pci_remove, +}; + +/** + * + * pti_init()- Overall entry/init call to the pti driver. + * It starts the registration process with the kernel. + * + * Returns: + * int __init, 0 for success + * otherwise value is an error + * + */ +static int __init pti_init(void) +{ + int retval = -EINVAL; + + /* First register module as tty device */ + + pti_tty_driver = alloc_tty_driver(1); + if (pti_tty_driver == NULL) { + pr_err("%s(%d): Memory allocation failed for ptiTTY driver\n", + __func__, __LINE__); + return -ENOMEM; + } + + pti_tty_driver->owner = THIS_MODULE; + pti_tty_driver->magic = TTY_DRIVER_MAGIC; + pti_tty_driver->driver_name = DRIVERNAME; + pti_tty_driver->name = TTYNAME; + pti_tty_driver->major = 0; + pti_tty_driver->minor_start = PTITTY_MINOR_START; + pti_tty_driver->minor_num = PTITTY_MINOR_NUM; + pti_tty_driver->num = PTITTY_MINOR_NUM; + pti_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM; + pti_tty_driver->subtype = SYSTEM_TYPE_SYSCONS; + pti_tty_driver->flags = TTY_DRIVER_REAL_RAW | + TTY_DRIVER_DYNAMIC_DEV; + pti_tty_driver->init_termios = tty_std_termios; + + tty_set_operations(pti_tty_driver, &pti_tty_driver_ops); + + retval = tty_register_driver(pti_tty_driver); + if (retval) { + pr_err("%s(%d): TTY registration failed of pti driver\n", + __func__, __LINE__); + pr_err("%s(%d): Error value returned: %d\n", + __func__, __LINE__, retval); + + pti_tty_driver = NULL; + return retval; + } + + retval = pci_register_driver(&pti_pci_driver); + + if (retval) { + pr_err("%s(%d): PCI registration failed of pti driver\n", + __func__, __LINE__); + pr_err("%s(%d): Error value returned: %d\n", + __func__, __LINE__, retval); + + tty_unregister_driver(pti_tty_driver); + pr_err("%s(%d): Unregistering TTY part of pti driver\n", + __func__, __LINE__); + pti_tty_driver = NULL; + return retval; + } + + return retval; +} + +/** + * pti_exit()- Unregisters this module as a tty and pci driver. + */ +static void __exit pti_exit(void) +{ + int retval; + + tty_unregister_device(pti_tty_driver, 0); + tty_unregister_device(pti_tty_driver, 1); + + retval = tty_unregister_driver(pti_tty_driver); + if (retval) { + pr_err("%s(%d): TTY unregistration failed of pti driver\n", + __func__, __LINE__); + pr_err("%s(%d): Error value returned: %d\n", + __func__, __LINE__, retval); + } + + pci_unregister_driver(&pti_pci_driver); + + retval = misc_deregister(&pti_char_driver); + if (retval) { + pr_err("%s(%d): CHAR unregistration failed of pti driver\n", + __func__, __LINE__); + pr_err("%s(%d): Error value returned: %d\n", + __func__, __LINE__, retval); + } + + unregister_console(&pti_console); + return; +} + +module_init(pti_init); +module_exit(pti_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ken Mills, Jay Freyensee"); +MODULE_DESCRIPTION("PTI Driver"); + diff --git a/include/linux/pti.h b/include/linux/pti.h new file mode 100644 index 000000000000..81af667bb2d5 --- /dev/null +++ b/include/linux/pti.h @@ -0,0 +1,42 @@ +/* + * Copyright (C) Intel 2011 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * The PTI (Parallel Trace Interface) driver directs trace data routed from + * various parts in the system out through the Intel Penwell PTI port and + * out of the mobile device for analysis with a debugging tool + * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7, + * compact JTAG, standard. + * + * This header file will allow other parts of the OS to use the + * interface to write out it's contents for debugging a mobile system. + */ + +#ifndef PTI_H_ +#define PTI_H_ + +/* offset for last dword of any PTI message. Part of MIPI P1149.7 */ +#define PTI_LASTDWORD_DTS 0x30 + +/* basic structure used as a write address to the PTI HW */ +struct pti_masterchannel { + u8 master; + u8 channel; +}; + +/* the following functions are defined in misc/pti.c */ +void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count); +struct pti_masterchannel *pti_request_masterchannel(u8 type); +void pti_release_masterchannel(struct pti_masterchannel *mc); + +#endif /*PTI_H_*/ -- cgit v1.3-14-g43fede From ee4f6b4b89665b92ead67deaa2e5d2ffa1af2b5f Mon Sep 17 00:00:00 2001 From: J Freyensee Date: Fri, 6 May 2011 16:56:50 -0700 Subject: n_tracerouter and n_tracesink ldisc additions. The n_tracerouter and n_tracesink line discpline drivers use the Linux tty line discpline framework to route trace data coming from a tty port (say UART for example) to the trace sink line discipline driver and to another tty port(say USB). Those these two line discipline drivers can be used together, independently from pti.c, they are part of the original implementation solution of the MIPI P1149.7, compact JTAG, PTI solution for Intel mobile platforms starting with the Medfield platform. Signed-off-by: J Freyensee Signed-off-by: Greg Kroah-Hartman --- drivers/tty/Kconfig | 31 ++++++ drivers/tty/Makefile | 2 + drivers/tty/n_tracerouter.c | 243 ++++++++++++++++++++++++++++++++++++++++++++ drivers/tty/n_tracesink.c | 238 +++++++++++++++++++++++++++++++++++++++++++ drivers/tty/n_tracesink.h | 36 +++++++ include/linux/tty.h | 2 + 6 files changed, 552 insertions(+) create mode 100644 drivers/tty/n_tracerouter.c create mode 100644 drivers/tty/n_tracesink.c create mode 100644 drivers/tty/n_tracesink.h (limited to 'include/linux') diff --git a/drivers/tty/Kconfig b/drivers/tty/Kconfig index 3fd7199301b6..bd7cc0527999 100644 --- a/drivers/tty/Kconfig +++ b/drivers/tty/Kconfig @@ -319,3 +319,34 @@ config N_GSM This line discipline provides support for the GSM MUX protocol and presents the mux as a set of 61 individual tty devices. +config TRACE_ROUTER + tristate "Trace data router for MIPI P1149.7 cJTAG standard" + depends on TRACE_SINK + default n + help + The trace router uses the Linux tty line discipline framework to + route trace data coming from a tty port (say UART for example) to + the trace sink line discipline driver and to another tty port (say + USB). This is part of a solution for the MIPI P1149.7, compact JTAG, + standard, which is for debugging mobile devices. The PTI driver in + drivers/misc/pti.c defines the majority of this MIPI solution. + + You should select this driver if the target kernel is meant for + a mobile device containing a modem. Then you will need to select + "Trace data sink for MIPI P1149.7 cJTAG standard" line discipline + driver. + +config TRACE_SINK + tristate "Trace data sink for MIPI P1149.7 cJTAG standard" + default n + help + The trace sink uses the Linux line discipline framework to receive + trace data coming from the trace router line discipline driver + to a user-defined tty port target, like USB. + This is to provide a way to extract modem trace data on + devices that do not have a PTI HW module, or just need modem + trace data to come out of a different HW output port. + This is part of a solution for the P1149.7, compact JTAG, standard. + + If you select this option, you need to select + "Trace data router for MIPI P1149.7 cJTAG standard". diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile index 690522fcb338..ea89b0bd15fe 100644 --- a/drivers/tty/Makefile +++ b/drivers/tty/Makefile @@ -6,6 +6,8 @@ obj-$(CONFIG_AUDIT) += tty_audit.o obj-$(CONFIG_MAGIC_SYSRQ) += sysrq.o obj-$(CONFIG_N_HDLC) += n_hdlc.o obj-$(CONFIG_N_GSM) += n_gsm.o +obj-$(CONFIG_TRACE_ROUTER) += n_tracerouter.o +obj-$(CONFIG_TRACE_SINK) += n_tracesink.o obj-$(CONFIG_R3964) += n_r3964.o obj-y += vt/ diff --git a/drivers/tty/n_tracerouter.c b/drivers/tty/n_tracerouter.c new file mode 100644 index 000000000000..1f063d3aa32f --- /dev/null +++ b/drivers/tty/n_tracerouter.c @@ -0,0 +1,243 @@ +/* + * n_tracerouter.c - Trace data router through tty space + * + * Copyright (C) Intel 2011 + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This trace router uses the Linux line discipline framework to route + * trace data coming from a HW Modem to a PTI (Parallel Trace Module) port. + * The solution is not specific to a HW modem and this line disciple can + * be used to route any stream of data in kernel space. + * This is part of a solution for the P1149.7, compact JTAG, standard. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "n_tracesink.h" + +/* + * Other ldisc drivers use 65536 which basically means, + * 'I can always accept 64k' and flow control is off. + * This number is deemed appropriate for this driver. + */ +#define RECEIVE_ROOM 65536 +#define DRIVERNAME "n_tracerouter" + +/* + * struct to hold private configuration data for this ldisc. + * opencalled is used to hold if this ldisc has been opened. + * kref_tty holds the tty reference the ldisc sits on top of. + */ +struct tracerouter_data { + u8 opencalled; + struct tty_struct *kref_tty; +}; +static struct tracerouter_data *tr_data; + +/* lock for when tty reference is being used */ +static DEFINE_MUTEX(routelock); + +/** + * n_tracerouter_open() - Called when a tty is opened by a SW entity. + * @tty: terminal device to the ldisc. + * + * Return: + * 0 for success. + * + * Caveats: This should only be opened one time per SW entity. + */ +static int n_tracerouter_open(struct tty_struct *tty) +{ + int retval = -EEXIST; + + mutex_lock(&routelock); + if (tr_data->opencalled == 0) { + + tr_data->kref_tty = tty_kref_get(tty); + if (tr_data->kref_tty == NULL) { + retval = -EFAULT; + } else { + tr_data->opencalled = 1; + tty->disc_data = tr_data; + tty->receive_room = RECEIVE_ROOM; + tty_driver_flush_buffer(tty); + retval = 0; + } + } + mutex_unlock(&routelock); + return retval; +} + +/** + * n_tracerouter_close() - close connection + * @tty: terminal device to the ldisc. + * + * Called when a software entity wants to close a connection. + */ +static void n_tracerouter_close(struct tty_struct *tty) +{ + struct tracerouter_data *tptr = tty->disc_data; + + mutex_lock(&routelock); + WARN_ON(tptr->kref_tty != tr_data->kref_tty); + tty_driver_flush_buffer(tty); + tty_kref_put(tr_data->kref_tty); + tr_data->kref_tty = NULL; + tr_data->opencalled = 0; + tty->disc_data = NULL; + mutex_unlock(&routelock); +} + +/** + * n_tracerouter_read() - read request from user space + * @tty: terminal device passed into the ldisc. + * @file: pointer to open file object. + * @buf: pointer to the data buffer that gets eventually returned. + * @nr: number of bytes of the data buffer that is returned. + * + * function that allows read() functionality in userspace. By default if this + * is not implemented it returns -EIO. This module is functioning like a + * router via n_tracerouter_receivebuf(), and there is no real requirement + * to implement this function. However, an error return value other than + * -EIO should be used just to show that there was an intent not to have + * this function implemented. Return value based on read() man pages. + * + * Return: + * -EINVAL + */ +static ssize_t n_tracerouter_read(struct tty_struct *tty, struct file *file, + unsigned char __user *buf, size_t nr) { + return -EINVAL; +} + +/** + * n_tracerouter_write() - Function that allows write() in userspace. + * @tty: terminal device passed into the ldisc. + * @file: pointer to open file object. + * @buf: pointer to the data buffer that gets eventually returned. + * @nr: number of bytes of the data buffer that is returned. + * + * By default if this is not implemented, it returns -EIO. + * This should not be implemented, ever, because + * 1. this driver is functioning like a router via + * n_tracerouter_receivebuf() + * 2. No writes to HW will ever go through this line discpline driver. + * However, an error return value other than -EIO should be used + * just to show that there was an intent not to have this function + * implemented. Return value based on write() man pages. + * + * Return: + * -EINVAL + */ +static ssize_t n_tracerouter_write(struct tty_struct *tty, struct file *file, + const unsigned char *buf, size_t nr) { + return -EINVAL; +} + +/** + * n_tracerouter_receivebuf() - Routing function for driver. + * @tty: terminal device passed into the ldisc. It's assumed + * tty will never be NULL. + * @cp: buffer, block of characters to be eventually read by + * someone, somewhere (user read() call or some kernel function). + * @fp: flag buffer. + * @count: number of characters (aka, bytes) in cp. + * + * This function takes the input buffer, cp, and passes it to + * an external API function for processing. + */ +static void n_tracerouter_receivebuf(struct tty_struct *tty, + const unsigned char *cp, + char *fp, int count) +{ + mutex_lock(&routelock); + n_tracesink_datadrain((u8 *) cp, count); + mutex_unlock(&routelock); +} + +/* + * Flush buffer is not impelemented as the ldisc has no internal buffering + * so the tty_driver_flush_buffer() is sufficient for this driver's needs. + */ + +static struct tty_ldisc_ops tty_ptirouter_ldisc = { + .owner = THIS_MODULE, + .magic = TTY_LDISC_MAGIC, + .name = DRIVERNAME, + .open = n_tracerouter_open, + .close = n_tracerouter_close, + .read = n_tracerouter_read, + .write = n_tracerouter_write, + .receive_buf = n_tracerouter_receivebuf +}; + +/** + * n_tracerouter_init - module initialisation + * + * Registers this module as a line discipline driver. + * + * Return: + * 0 for success, any other value error. + */ +static int __init n_tracerouter_init(void) +{ + int retval; + + tr_data = kzalloc(sizeof(struct tracerouter_data), GFP_KERNEL); + if (tr_data == NULL) + return -ENOMEM; + + + /* Note N_TRACEROUTER is defined in linux/tty.h */ + retval = tty_register_ldisc(N_TRACEROUTER, &tty_ptirouter_ldisc); + if (retval < 0) { + pr_err("%s: Registration failed: %d\n", __func__, retval); + kfree(tr_data); + } + return retval; +} + +/** + * n_tracerouter_exit - module unload + * + * Removes this module as a line discipline driver. + */ +static void __exit n_tracerouter_exit(void) +{ + int retval = tty_unregister_ldisc(N_TRACEROUTER); + + if (retval < 0) + pr_err("%s: Unregistration failed: %d\n", __func__, retval); + else + kfree(tr_data); +} + +module_init(n_tracerouter_init); +module_exit(n_tracerouter_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jay Freyensee"); +MODULE_ALIAS_LDISC(N_TRACEROUTER); +MODULE_DESCRIPTION("Trace router ldisc driver"); diff --git a/drivers/tty/n_tracesink.c b/drivers/tty/n_tracesink.c new file mode 100644 index 000000000000..ddce58b973d2 --- /dev/null +++ b/drivers/tty/n_tracesink.c @@ -0,0 +1,238 @@ +/* + * n_tracesink.c - Trace data router and sink path through tty space. + * + * Copyright (C) Intel 2011 + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * The trace sink uses the Linux line discipline framework to receive + * trace data coming from the PTI source line discipline driver + * to a user-desired tty port, like USB. + * This is to provide a way to extract modem trace data on + * devices that do not have a PTI HW module, or just need modem + * trace data to come out of a different HW output port. + * This is part of a solution for the P1149.7, compact JTAG, standard. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "n_tracesink.h" + +/* + * Other ldisc drivers use 65536 which basically means, + * 'I can always accept 64k' and flow control is off. + * This number is deemed appropriate for this driver. + */ +#define RECEIVE_ROOM 65536 +#define DRIVERNAME "n_tracesink" + +/* + * there is a quirk with this ldisc is he can write data + * to a tty from anyone calling his kernel API, which + * meets customer requirements in the drivers/misc/pti.c + * project. So he needs to know when he can and cannot write when + * the API is called. In theory, the API can be called + * after an init() but before a successful open() which + * would crash the system if tty is not checked. + */ +static struct tty_struct *this_tty; +static DEFINE_MUTEX(writelock); + +/** + * n_tracesink_open() - Called when a tty is opened by a SW entity. + * @tty: terminal device to the ldisc. + * + * Return: + * 0 for success, + * -EFAULT = couldn't get a tty kref n_tracesink will sit + * on top of + * -EEXIST = open() called successfully once and it cannot + * be called again. + * + * Caveats: open() should only be successful the first time a + * SW entity calls it. + */ +static int n_tracesink_open(struct tty_struct *tty) +{ + int retval = -EEXIST; + + mutex_lock(&writelock); + if (this_tty == NULL) { + this_tty = tty_kref_get(tty); + if (this_tty == NULL) { + retval = -EFAULT; + } else { + tty->disc_data = this_tty; + tty_driver_flush_buffer(tty); + retval = 0; + } + } + mutex_unlock(&writelock); + + return retval; +} + +/** + * n_tracesink_close() - close connection + * @tty: terminal device to the ldisc. + * + * Called when a software entity wants to close a connection. + */ +static void n_tracesink_close(struct tty_struct *tty) +{ + mutex_lock(&writelock); + tty_driver_flush_buffer(tty); + tty_kref_put(this_tty); + this_tty = NULL; + tty->disc_data = NULL; + mutex_unlock(&writelock); +} + +/** + * n_tracesink_read() - read request from user space + * @tty: terminal device passed into the ldisc. + * @file: pointer to open file object. + * @buf: pointer to the data buffer that gets eventually returned. + * @nr: number of bytes of the data buffer that is returned. + * + * function that allows read() functionality in userspace. By default if this + * is not implemented it returns -EIO. This module is functioning like a + * router via n_tracesink_receivebuf(), and there is no real requirement + * to implement this function. However, an error return value other than + * -EIO should be used just to show that there was an intent not to have + * this function implemented. Return value based on read() man pages. + * + * Return: + * -EINVAL + */ +static ssize_t n_tracesink_read(struct tty_struct *tty, struct file *file, + unsigned char __user *buf, size_t nr) { + return -EINVAL; +} + +/** + * n_tracesink_write() - Function that allows write() in userspace. + * @tty: terminal device passed into the ldisc. + * @file: pointer to open file object. + * @buf: pointer to the data buffer that gets eventually returned. + * @nr: number of bytes of the data buffer that is returned. + * + * By default if this is not implemented, it returns -EIO. + * This should not be implemented, ever, because + * 1. this driver is functioning like a router via + * n_tracesink_receivebuf() + * 2. No writes to HW will ever go through this line discpline driver. + * However, an error return value other than -EIO should be used + * just to show that there was an intent not to have this function + * implemented. Return value based on write() man pages. + * + * Return: + * -EINVAL + */ +static ssize_t n_tracesink_write(struct tty_struct *tty, struct file *file, + const unsigned char *buf, size_t nr) { + return -EINVAL; +} + +/** + * n_tracesink_datadrain() - Kernel API function used to route + * trace debugging data to user-defined + * port like USB. + * + * @buf: Trace debuging data buffer to write to tty target + * port. Null value will return with no write occurring. + * @count: Size of buf. Value of 0 or a negative number will + * return with no write occuring. + * + * Caveat: If this line discipline does not set the tty it sits + * on top of via an open() call, this API function will not + * call the tty's write() call because it will have no pointer + * to call the write(). + */ +void n_tracesink_datadrain(u8 *buf, int count) +{ + mutex_lock(&writelock); + + if ((buf != NULL) && (count > 0) && (this_tty != NULL)) + this_tty->ops->write(this_tty, buf, count); + + mutex_unlock(&writelock); +} +EXPORT_SYMBOL_GPL(n_tracesink_datadrain); + +/* + * Flush buffer is not impelemented as the ldisc has no internal buffering + * so the tty_driver_flush_buffer() is sufficient for this driver's needs. + */ + +/* + * tty_ldisc function operations for this driver. + */ +static struct tty_ldisc_ops tty_n_tracesink = { + .owner = THIS_MODULE, + .magic = TTY_LDISC_MAGIC, + .name = DRIVERNAME, + .open = n_tracesink_open, + .close = n_tracesink_close, + .read = n_tracesink_read, + .write = n_tracesink_write +}; + +/** + * n_tracesink_init- module initialisation + * + * Registers this module as a line discipline driver. + * + * Return: + * 0 for success, any other value error. + */ +static int __init n_tracesink_init(void) +{ + /* Note N_TRACESINK is defined in linux/tty.h */ + int retval = tty_register_ldisc(N_TRACESINK, &tty_n_tracesink); + + if (retval < 0) + pr_err("%s: Registration failed: %d\n", __func__, retval); + + return retval; +} + +/** + * n_tracesink_exit - module unload + * + * Removes this module as a line discipline driver. + */ +static void __exit n_tracesink_exit(void) +{ + int retval = tty_unregister_ldisc(N_TRACESINK); + + if (retval < 0) + pr_err("%s: Unregistration failed: %d\n", __func__, retval); +} + +module_init(n_tracesink_init); +module_exit(n_tracesink_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jay Freyensee"); +MODULE_ALIAS_LDISC(N_TRACESINK); +MODULE_DESCRIPTION("Trace sink ldisc driver"); diff --git a/drivers/tty/n_tracesink.h b/drivers/tty/n_tracesink.h new file mode 100644 index 000000000000..a68bb44f1ef5 --- /dev/null +++ b/drivers/tty/n_tracesink.h @@ -0,0 +1,36 @@ +/* + * n_tracesink.h - Kernel driver API to route trace data in kernel space. + * + * Copyright (C) Intel 2011 + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * The PTI (Parallel Trace Interface) driver directs trace data routed from + * various parts in the system out through the Intel Penwell PTI port and + * out of the mobile device for analysis with a debugging tool + * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7, + * compact JTAG, standard. + * + * This header file is used by n_tracerouter to be able to send the + * data of it's tty port to the tty port this module sits. This + * mechanism can also be used independent of the PTI module. + * + */ + +#ifndef N_TRACESINK_H_ +#define N_TRACESINK_H_ + +void n_tracesink_datadrain(u8 *buf, int count); + +#endif diff --git a/include/linux/tty.h b/include/linux/tty.h index 4db4ca79f895..d6f05292e456 100644 --- a/include/linux/tty.h +++ b/include/linux/tty.h @@ -50,6 +50,8 @@ #define N_CAIF 20 /* CAIF protocol for talking to modems */ #define N_GSM0710 21 /* GSM 0710 Mux */ #define N_TI_WL 22 /* for TI's WL BT, FM, GPS combo chips */ +#define N_TRACESINK 23 /* Trace data routing for MIPI P1149.7 */ +#define N_TRACEROUTER 24 /* Trace data routing for MIPI P1149.7 */ /* * This character is the same as _POSIX_VDISABLE: it cannot be used as -- cgit v1.3-14-g43fede From 4539c24fe4f92c09ee668ef959d3e8180df619b9 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Tue, 17 May 2011 16:12:36 -0600 Subject: tty/serial: Add explicit PORT_TEGRA type Tegra's UART is currently auto-detected as PORT_XSCALE due to register bit UART_IER.UUE being writable. However, the Tegra documentation states that this register bit is reserved. Hence, we should not program it. Instead, the documentation specifies that the UART is 16550 compatible. However, Tegra does need register bit UART_IER.RTOIE set, which is not enabled by any 16550 port type. This was not noticed before, since PORT_XSCALE enables CAP_UUE, which conflates both UUE and RTOIE bit programming. This change defines PORT_TEGRA that doesn't set UART_CAP_UUE, but does set UART_CAP_RTOIE, which is a new capability indicating that the RTOIE bit needs to be enabled. Based-on-code-by: Laxman Dewangan Cc: Laxman Dewangan Signed-off-by: Stephen Warren Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250.c | 14 ++++++++++++-- drivers/tty/serial/8250.h | 1 + include/linux/serial_core.h | 3 ++- include/linux/serial_reg.h | 1 + 4 files changed, 16 insertions(+), 3 deletions(-) (limited to 'include/linux') diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index 54482d724fee..a5e290de8c93 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -271,7 +271,7 @@ static const struct serial8250_config uart_config[] = { .fifo_size = 32, .tx_loadsz = 32, .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, - .flags = UART_CAP_FIFO | UART_CAP_UUE, + .flags = UART_CAP_FIFO | UART_CAP_UUE | UART_CAP_RTOIE, }, [PORT_RM9000] = { .name = "RM9000", @@ -301,6 +301,14 @@ static const struct serial8250_config uart_config[] = { .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, .flags = UART_CAP_FIFO | UART_CAP_AFE, }, + [PORT_TEGRA] = { + .name = "Tegra", + .fifo_size = 32, + .tx_loadsz = 8, + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_01 | + UART_FCR_T_TRIG_01, + .flags = UART_CAP_FIFO | UART_CAP_RTOIE, + }, }; #if defined(CONFIG_MIPS_ALCHEMY) @@ -2403,7 +2411,9 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, UART_ENABLE_MS(&up->port, termios->c_cflag)) up->ier |= UART_IER_MSI; if (up->capabilities & UART_CAP_UUE) - up->ier |= UART_IER_UUE | UART_IER_RTOIE; + up->ier |= UART_IER_UUE; + if (up->capabilities & UART_CAP_RTOIE) + up->ier |= UART_IER_RTOIE; serial_out(up, UART_IER, up->ier); diff --git a/drivers/tty/serial/8250.h b/drivers/tty/serial/8250.h index d13b586c0f72..6edf4a6a22d4 100644 --- a/drivers/tty/serial/8250.h +++ b/drivers/tty/serial/8250.h @@ -42,6 +42,7 @@ struct serial8250_config { #define UART_CAP_SLEEP (1 << 10) /* UART has IER sleep */ #define UART_CAP_AFE (1 << 11) /* MCR-based hw flow control */ #define UART_CAP_UUE (1 << 12) /* UART needs IER bit 6 set (Xscale) */ +#define UART_CAP_RTOIE (1 << 13) /* UART needs IER bit 4 set (Xscale, Tegra) */ #define UART_BUG_QUOT (1 << 0) /* UART has buggy quot LSB */ #define UART_BUG_TXEN (1 << 1) /* UART has buggy TX IIR status */ diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index 95d479ba514e..a5c31146a337 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -45,7 +45,8 @@ #define PORT_OCTEON 17 /* Cavium OCTEON internal UART */ #define PORT_AR7 18 /* Texas Instruments AR7 internal UART */ #define PORT_U6_16550A 19 /* ST-Ericsson U6xxx internal UART */ -#define PORT_MAX_8250 19 /* max port ID */ +#define PORT_TEGRA 20 /* NVIDIA Tegra internal UART */ +#define PORT_MAX_8250 20 /* max port ID */ /* * ARM specific type numbers. These are not currently guaranteed diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h index 3ecb71a9e505..5f66e8499fb9 100644 --- a/include/linux/serial_reg.h +++ b/include/linux/serial_reg.h @@ -57,6 +57,7 @@ * ST16C654: 8 16 56 60 8 16 32 56 PORT_16654 * TI16C750: 1 16 32 56 xx xx xx xx PORT_16750 * TI16C752: 8 16 56 60 8 16 32 56 + * Tegra: 1 4 8 14 16 8 4 1 PORT_TEGRA */ #define UART_FCR_R_TRIG_00 0x00 #define UART_FCR_R_TRIG_01 0x40 -- cgit v1.3-14-g43fede From 5f873bae704cf8b7cbd64b5720912266286c9146 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Tue, 17 May 2011 16:12:37 -0600 Subject: tty/serial: Fix break handling for PORT_TEGRA When a break is received, Tegra's UART apparently fills the FIFO with 0 bytes. These must be drained so that they aren't interpreted as actual data received. This allows e.g. MAGIC_SYSRQ to work on Tegra's UARTs. v2: Added FIXME comment to clear_rx_fifo Originally-by: Laxman Dewangan Cc: Laxman Dewangan Signed-off-by: Stephen Warren Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250.c | 28 ++++++++++++++++++++++++++++ include/linux/serial_reg.h | 1 + 2 files changed, 29 insertions(+) (limited to 'include/linux') diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index a5e290de8c93..b40f7b90c81d 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -1433,6 +1433,27 @@ static void serial8250_enable_ms(struct uart_port *port) serial_out(up, UART_IER, up->ier); } +/* + * Clear the Tegra rx fifo after a break + * + * FIXME: This needs to become a port specific callback once we have a + * framework for this + */ +static void clear_rx_fifo(struct uart_8250_port *up) +{ + unsigned int status, tmout = 10000; + do { + status = serial_in(up, UART_LSR); + if (status & (UART_LSR_FIFOE | UART_LSR_BRK_ERROR_BITS)) + status = serial_in(up, UART_RX); + else + break; + if (--tmout == 0) + break; + udelay(1); + } while (1); +} + static void receive_chars(struct uart_8250_port *up, unsigned int *status) { @@ -1467,6 +1488,13 @@ receive_chars(struct uart_8250_port *up, unsigned int *status) if (lsr & UART_LSR_BI) { lsr &= ~(UART_LSR_FE | UART_LSR_PE); up->port.icount.brk++; + /* + * If tegra port then clear the rx fifo to + * accept another break/character. + */ + if (up->port.type == PORT_TEGRA) + clear_rx_fifo(up); + /* * We do the SysRQ and SAK checking * here because otherwise the break diff --git a/include/linux/serial_reg.h b/include/linux/serial_reg.h index 5f66e8499fb9..c75bda37c18e 100644 --- a/include/linux/serial_reg.h +++ b/include/linux/serial_reg.h @@ -119,6 +119,7 @@ #define UART_MCR_DTR 0x01 /* DTR complement */ #define UART_LSR 5 /* In: Line Status Register */ +#define UART_LSR_FIFOE 0x80 /* Fifo error */ #define UART_LSR_TEMT 0x40 /* Transmitter empty */ #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */ #define UART_LSR_BI 0x10 /* Break interrupt indicator */ -- cgit v1.3-14-g43fede