diff options
Diffstat (limited to 'drivers/staging/dgrp/dgrp_dpa_ops.c')
| -rw-r--r-- | drivers/staging/dgrp/dgrp_dpa_ops.c | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/drivers/staging/dgrp/dgrp_dpa_ops.c b/drivers/staging/dgrp/dgrp_dpa_ops.c new file mode 100644 index 000000000000..49e670915e5c --- /dev/null +++ b/drivers/staging/dgrp/dgrp_dpa_ops.c @@ -0,0 +1,556 @@ +/* + * + * Copyright 1999 Digi International (www.digi.com) + * James Puzzo <jamesp at digi dot com> + * + * 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, or (at your option) + * any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; without even the + * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR + * PURPOSE. See the GNU General Public License for more details. + * + */ + +/* + * + * Filename: + * + * dgrp_dpa_ops.c + * + * Description: + * + * Handle the file operations required for the "dpa" devices. + * Includes those functions required to register the "dpa" devices + * in "/proc". + * + * Author: + * + * James A. Puzzo + * + */ + +#include <linux/module.h> +#include <linux/proc_fs.h> +#include <linux/tty.h> +#include <linux/poll.h> +#include <linux/cred.h> +#include <linux/sched.h> +#include <linux/ratelimit.h> +#include <asm/unaligned.h> + +#include "dgrp_common.h" + +/* File operation declarations */ +static int dgrp_dpa_open(struct inode *, struct file *); +static int dgrp_dpa_release(struct inode *, struct file *); +static ssize_t dgrp_dpa_read(struct file *, char __user *, size_t, loff_t *); +static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd, + unsigned long arg); +static unsigned int dgrp_dpa_select(struct file *, struct poll_table_struct *); + +static const struct file_operations dpa_ops = { + .owner = THIS_MODULE, + .read = dgrp_dpa_read, + .poll = dgrp_dpa_select, + .unlocked_ioctl = dgrp_dpa_ioctl, + .open = dgrp_dpa_open, + .release = dgrp_dpa_release, +}; + +static struct inode_operations dpa_inode_ops = { + .permission = dgrp_inode_permission +}; + + + +struct digi_node { + uint nd_state; /* Node state: 1 = up, 0 = down. */ + uint nd_chan_count; /* Number of channels found */ + uint nd_tx_byte; /* Tx data count */ + uint nd_rx_byte; /* RX data count */ + u8 nd_ps_desc[MAX_DESC_LEN]; /* Description from PS */ +}; + +#define DIGI_GETNODE (('d'<<8) | 249) /* get board info */ + + +struct digi_chan { + uint ch_port; /* Port number to get info on */ + uint ch_open; /* 1 if open, 0 if not */ + uint ch_txcount; /* TX data count */ + uint ch_rxcount; /* RX data count */ + uint ch_s_brate; /* Realport BRATE */ + uint ch_s_estat; /* Realport ELAST */ + uint ch_s_cflag; /* Realport CFLAG */ + uint ch_s_iflag; /* Realport IFLAG */ + uint ch_s_oflag; /* Realport OFLAG */ + uint ch_s_xflag; /* Realport XFLAG */ + uint ch_s_mstat; /* Realport MLAST */ +}; + +#define DIGI_GETCHAN (('d'<<8) | 248) /* get channel info */ + + +struct digi_vpd { + int vpd_len; + char vpd_data[VPDSIZE]; +}; + +#define DIGI_GETVPD (('d'<<8) | 246) /* get VPD info */ + + +struct digi_debug { + int onoff; + int port; +}; + +#define DIGI_SETDEBUG (('d'<<8) | 247) /* set debug info */ + + +void dgrp_register_dpa_hook(struct proc_dir_entry *de) +{ + struct nd_struct *node = de->data; + + de->proc_iops = &dpa_inode_ops; + de->proc_fops = &dpa_ops; + + node->nd_dpa_de = de; + spin_lock_init(&node->nd_dpa_lock); +} + +/* + * dgrp_dpa_open -- open the DPA device for a particular PortServer + */ +static int dgrp_dpa_open(struct inode *inode, struct file *file) +{ + struct nd_struct *nd; + int rtn = 0; + + struct proc_dir_entry *de; + + rtn = try_module_get(THIS_MODULE); + if (!rtn) + return -ENXIO; + + rtn = 0; + + if (!capable(CAP_SYS_ADMIN)) { + rtn = -EPERM; + goto done; + } + + /* + * Make sure that the "private_data" field hasn't already been used. + */ + if (file->private_data) { + rtn = -EINVAL; + goto done; + } + + /* + * Get the node pointer, and fail if it doesn't exist. + */ + de = PDE(inode); + if (!de) { + rtn = -ENXIO; + goto done; + } + nd = (struct nd_struct *)de->data; + if (!nd) { + rtn = -ENXIO; + goto done; + } + + file->private_data = (void *) nd; + + /* + * Allocate the DPA buffer. + */ + + if (nd->nd_dpa_buf) { + rtn = -EBUSY; + } else { + nd->nd_dpa_buf = kmalloc(DPA_MAX, GFP_KERNEL); + + if (!nd->nd_dpa_buf) { + rtn = -ENOMEM; + } else { + nd->nd_dpa_out = 0; + nd->nd_dpa_in = 0; + nd->nd_dpa_lbolt = jiffies; + } + } + +done: + + if (rtn) + module_put(THIS_MODULE); + return rtn; +} + +/* + * dgrp_dpa_release -- close the DPA device for a particular PortServer + */ +static int dgrp_dpa_release(struct inode *inode, struct file *file) +{ + struct nd_struct *nd; + u8 *buf; + unsigned long lock_flags; + + /* + * Get the node pointer, and quit if it doesn't exist. + */ + nd = (struct nd_struct *)(file->private_data); + if (!nd) + goto done; + + /* + * Free the dpa buffer. + */ + + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + + buf = nd->nd_dpa_buf; + + nd->nd_dpa_buf = NULL; + nd->nd_dpa_out = nd->nd_dpa_in; + + /* + * Wakeup any thread waiting for buffer space. + */ + + if (nd->nd_dpa_flag & DPA_WAIT_SPACE) { + nd->nd_dpa_flag &= ~DPA_WAIT_SPACE; + wake_up_interruptible(&nd->nd_dpa_wqueue); + } + + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + + kfree(buf); + +done: + module_put(THIS_MODULE); + file->private_data = NULL; + return 0; +} + +/* + * dgrp_dpa_read + * + * Copy data from the monitoring buffer to the user, freeing space + * in the monitoring buffer for more messages + */ +static ssize_t dgrp_dpa_read(struct file *file, char __user *buf, size_t count, + loff_t *ppos) +{ + struct nd_struct *nd; + int n; + int r; + int offset = 0; + int res = 0; + ssize_t rtn; + unsigned long lock_flags; + + /* + * Get the node pointer, and quit if it doesn't exist. + */ + nd = (struct nd_struct *)(file->private_data); + if (!nd) + return -ENXIO; + + /* + * Wait for some data to appear in the buffer. + */ + + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + + for (;;) { + n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK; + + if (n != 0) + break; + + nd->nd_dpa_flag |= DPA_WAIT_DATA; + + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + + /* + * Go to sleep waiting until the condition becomes true. + */ + rtn = wait_event_interruptible(nd->nd_dpa_wqueue, + ((nd->nd_dpa_flag & DPA_WAIT_DATA) == 0)); + + if (rtn) + return rtn; + + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + } + + /* + * Read whatever is there. + */ + + if (n > count) + n = count; + + res = n; + + r = DPA_MAX - nd->nd_dpa_out; + + if (r <= n) { + + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + rtn = copy_to_user((void __user *)buf, + nd->nd_dpa_buf + nd->nd_dpa_out, r); + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + + if (rtn) { + rtn = -EFAULT; + goto done; + } + + nd->nd_dpa_out = 0; + n -= r; + offset = r; + } + + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + rtn = copy_to_user((void __user *)buf + offset, + nd->nd_dpa_buf + nd->nd_dpa_out, n); + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + + if (rtn) { + rtn = -EFAULT; + goto done; + } + + nd->nd_dpa_out += n; + + *ppos += res; + + rtn = res; + + /* + * Wakeup any thread waiting for buffer space. + */ + + n = (nd->nd_dpa_in - nd->nd_dpa_out) & DPA_MASK; + + if (nd->nd_dpa_flag & DPA_WAIT_SPACE && + (DPA_MAX - n) > DPA_HIGH_WATER) { + nd->nd_dpa_flag &= ~DPA_WAIT_SPACE; + wake_up_interruptible(&nd->nd_dpa_wqueue); + } + + done: + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + return rtn; +} + +static unsigned int dgrp_dpa_select(struct file *file, + struct poll_table_struct *table) +{ + unsigned int retval = 0; + struct nd_struct *nd = file->private_data; + + if (nd->nd_dpa_out != nd->nd_dpa_in) + retval |= POLLIN | POLLRDNORM; /* Conditionally readable */ + + retval |= POLLOUT | POLLWRNORM; /* Always writeable */ + + return retval; +} + +static long dgrp_dpa_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + + struct nd_struct *nd; + struct digi_chan getchan; + struct digi_node getnode; + struct ch_struct *ch; + struct digi_debug setdebug; + struct digi_vpd vpd; + unsigned int port; + void __user *uarg = (void __user *) arg; + + nd = file->private_data; + + switch (cmd) { + case DIGI_GETCHAN: + if (copy_from_user(&getchan, uarg, sizeof(struct digi_chan))) + return -EFAULT; + + port = getchan.ch_port; + + if (port < 0 || port > nd->nd_chan_count) + return -EINVAL; + + ch = nd->nd_chan + port; + + getchan.ch_open = (ch->ch_open_count > 0) ? 1 : 0; + getchan.ch_txcount = ch->ch_txcount; + getchan.ch_rxcount = ch->ch_rxcount; + getchan.ch_s_brate = ch->ch_s_brate; + getchan.ch_s_estat = ch->ch_s_elast; + getchan.ch_s_cflag = ch->ch_s_cflag; + getchan.ch_s_iflag = ch->ch_s_iflag; + getchan.ch_s_oflag = ch->ch_s_oflag; + getchan.ch_s_xflag = ch->ch_s_xflag; + getchan.ch_s_mstat = ch->ch_s_mlast; + + if (copy_to_user(uarg, &getchan, sizeof(struct digi_chan))) + return -EFAULT; + break; + + + case DIGI_GETNODE: + getnode.nd_state = (nd->nd_state & NS_READY) ? 1 : 0; + getnode.nd_chan_count = nd->nd_chan_count; + getnode.nd_tx_byte = nd->nd_tx_byte; + getnode.nd_rx_byte = nd->nd_rx_byte; + + memset(&getnode.nd_ps_desc, 0, MAX_DESC_LEN); + strncpy(getnode.nd_ps_desc, nd->nd_ps_desc, MAX_DESC_LEN); + + if (copy_to_user(uarg, &getnode, sizeof(struct digi_node))) + return -EFAULT; + break; + + + case DIGI_SETDEBUG: + if (copy_from_user(&setdebug, uarg, sizeof(struct digi_debug))) + return -EFAULT; + + nd->nd_dpa_debug = setdebug.onoff; + nd->nd_dpa_port = setdebug.port; + break; + + + case DIGI_GETVPD: + if (nd->nd_vpd_len > 0) { + vpd.vpd_len = nd->nd_vpd_len; + memcpy(&vpd.vpd_data, &nd->nd_vpd, nd->nd_vpd_len); + } else { + vpd.vpd_len = 0; + } + + if (copy_to_user(uarg, &vpd, sizeof(struct digi_vpd))) + return -EFAULT; + break; + } + + return 0; +} + +/** + * dgrp_dpa() -- send data to the device monitor queue + * @nd: pointer to a node structure + * @buf: buffer of data to copy to the monitoring buffer + * @len: number of bytes to transfer to the buffer + * + * Called by the net device routines to send data to the device + * monitor queue. If the device monitor buffer is too full to + * accept the data, it waits until the buffer is ready. + */ +static void dgrp_dpa(struct nd_struct *nd, u8 *buf, int nbuf) +{ + int n; + int r; + unsigned long lock_flags; + + /* + * Grab DPA lock. + */ + spin_lock_irqsave(&nd->nd_dpa_lock, lock_flags); + + /* + * Loop while data remains. + */ + while (nbuf > 0 && nd->nd_dpa_buf != NULL) { + + n = (nd->nd_dpa_out - nd->nd_dpa_in - 1) & DPA_MASK; + + /* + * Enforce flow control on the DPA device. + */ + if (n < (DPA_MAX - DPA_HIGH_WATER)) + nd->nd_dpa_flag |= DPA_WAIT_SPACE; + + /* + * This should never happen, as the flow control above + * should have stopped things before they got to this point. + */ + if (n == 0) { + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); + return; + } + + /* + * Copy as much data as will fit. + */ + + if (n > nbuf) + n = nbuf; + + r = DPA_MAX - nd->nd_dpa_in; + + if (r <= n) { + memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, r); + + n -= r; + + nd->nd_dpa_in = 0; + + buf += r; + nbuf -= r; + } + + memcpy(nd->nd_dpa_buf + nd->nd_dpa_in, buf, n); + + nd->nd_dpa_in += n; + + buf += n; + nbuf -= n; + + if (nd->nd_dpa_in >= DPA_MAX) + pr_info_ratelimited("%s - nd->nd_dpa_in (%i) >= DPA_MAX\n", + __func__, nd->nd_dpa_in); + + /* + * Wakeup any thread waiting for data + */ + if (nd->nd_dpa_flag & DPA_WAIT_DATA) { + nd->nd_dpa_flag &= ~DPA_WAIT_DATA; + wake_up_interruptible(&nd->nd_dpa_wqueue); + } + } + + /* + * Release the DPA lock. + */ + spin_unlock_irqrestore(&nd->nd_dpa_lock, lock_flags); +} + +/** + * dgrp_monitor_data() -- builds a DPA data packet + * @nd: pointer to a node structure + * @type: type of message to be logged in the DPA buffer + * @buf: buffer of data to be logged in the DPA buffer + * @size -- number of bytes in the "buf" buffer + */ +void dgrp_dpa_data(struct nd_struct *nd, int type, u8 *buf, int size) +{ + u8 header[5]; + + header[0] = type; + + put_unaligned_be32(size, header + 1); + + dgrp_dpa(nd, header, sizeof(header)); + dgrp_dpa(nd, buf, size); +} |