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path: root/drivers/bluetooth/hci_ldisc.c
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Diffstat (limited to 'drivers/bluetooth/hci_ldisc.c')
-rw-r--r--drivers/bluetooth/hci_ldisc.c593
1 files changed, 593 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
new file mode 100644
index 000000000000..9075bbb56ad4
--- /dev/null
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -0,0 +1,593 @@
+/*
+ BlueZ - Bluetooth protocol stack for Linux
+ Copyright (C) 2000-2001 Qualcomm Incorporated
+
+ Written 2000,2001 by Maxim Krasnyansky <maxk@qualcomm.com>
+
+ 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;
+
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+ IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) AND AUTHOR(S) BE LIABLE FOR ANY
+ CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES
+ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+ ALL LIABILITY, INCLUDING LIABILITY FOR INFRINGEMENT OF ANY PATENTS,
+ COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS, RELATING TO USE OF THIS
+ SOFTWARE IS DISCLAIMED.
+*/
+
+/*
+ * Bluetooth HCI UART driver.
+ *
+ * $Id: hci_ldisc.c,v 1.5 2002/10/02 18:37:20 maxk Exp $
+ */
+#define VERSION "2.1"
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/poll.h>
+
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/signal.h>
+#include <linux/ioctl.h>
+#include <linux/skbuff.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "hci_uart.h"
+
+#ifndef CONFIG_BT_HCIUART_DEBUG
+#undef BT_DBG
+#define BT_DBG( A... )
+#undef BT_DMP
+#define BT_DMP( A... )
+#endif
+
+static int reset = 0;
+
+static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
+
+int hci_uart_register_proto(struct hci_uart_proto *p)
+{
+ if (p->id >= HCI_UART_MAX_PROTO)
+ return -EINVAL;
+
+ if (hup[p->id])
+ return -EEXIST;
+
+ hup[p->id] = p;
+ return 0;
+}
+
+int hci_uart_unregister_proto(struct hci_uart_proto *p)
+{
+ if (p->id >= HCI_UART_MAX_PROTO)
+ return -EINVAL;
+
+ if (!hup[p->id])
+ return -EINVAL;
+
+ hup[p->id] = NULL;
+ return 0;
+}
+
+static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
+{
+ if (id >= HCI_UART_MAX_PROTO)
+ return NULL;
+ return hup[id];
+}
+
+static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
+{
+ struct hci_dev *hdev = hu->hdev;
+
+ /* Update HCI stat counters */
+ switch (pkt_type) {
+ case HCI_COMMAND_PKT:
+ hdev->stat.cmd_tx++;
+ break;
+
+ case HCI_ACLDATA_PKT:
+ hdev->stat.acl_tx++;
+ break;
+
+ case HCI_SCODATA_PKT:
+ hdev->stat.cmd_tx++;
+ break;
+ }
+}
+
+static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
+{
+ struct sk_buff *skb = hu->tx_skb;
+ if (!skb)
+ skb = hu->proto->dequeue(hu);
+ else
+ hu->tx_skb = NULL;
+ return skb;
+}
+
+int hci_uart_tx_wakeup(struct hci_uart *hu)
+{
+ struct tty_struct *tty = hu->tty;
+ struct hci_dev *hdev = hu->hdev;
+ struct sk_buff *skb;
+
+ if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
+ set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
+ return 0;
+ }
+
+ BT_DBG("");
+
+restart:
+ clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
+
+ while ((skb = hci_uart_dequeue(hu))) {
+ int len;
+
+ set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ len = tty->driver->write(tty, skb->data, skb->len);
+ hdev->stat.byte_tx += len;
+
+ skb_pull(skb, len);
+ if (skb->len) {
+ hu->tx_skb = skb;
+ break;
+ }
+
+ hci_uart_tx_complete(hu, skb->pkt_type);
+ kfree_skb(skb);
+ }
+
+ if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
+ goto restart;
+
+ clear_bit(HCI_UART_SENDING, &hu->tx_state);
+ return 0;
+}
+
+/* ------- Interface to HCI layer ------ */
+/* Initialize device */
+static int hci_uart_open(struct hci_dev *hdev)
+{
+ BT_DBG("%s %p", hdev->name, hdev);
+
+ /* Nothing to do for UART driver */
+
+ set_bit(HCI_RUNNING, &hdev->flags);
+ return 0;
+}
+
+/* Reset device */
+static int hci_uart_flush(struct hci_dev *hdev)
+{
+ struct hci_uart *hu = (struct hci_uart *) hdev->driver_data;
+ struct tty_struct *tty = hu->tty;
+
+ BT_DBG("hdev %p tty %p", hdev, tty);
+
+ if (hu->tx_skb) {
+ kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
+ }
+
+ /* Flush any pending characters in the driver and discipline. */
+ tty_ldisc_flush(tty);
+ if (tty->driver->flush_buffer)
+ tty->driver->flush_buffer(tty);
+
+ if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
+ hu->proto->flush(hu);
+
+ return 0;
+}
+
+/* Close device */
+static int hci_uart_close(struct hci_dev *hdev)
+{
+ BT_DBG("hdev %p", hdev);
+
+ if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
+ return 0;
+
+ hci_uart_flush(hdev);
+ return 0;
+}
+
+/* Send frames from HCI layer */
+static int hci_uart_send_frame(struct sk_buff *skb)
+{
+ struct hci_dev* hdev = (struct hci_dev *) skb->dev;
+ struct tty_struct *tty;
+ struct hci_uart *hu;
+
+ if (!hdev) {
+ BT_ERR("Frame for uknown device (hdev=NULL)");
+ return -ENODEV;
+ }
+
+ if (!test_bit(HCI_RUNNING, &hdev->flags))
+ return -EBUSY;
+
+ hu = (struct hci_uart *) hdev->driver_data;
+ tty = hu->tty;
+
+ BT_DBG("%s: type %d len %d", hdev->name, skb->pkt_type, skb->len);
+
+ hu->proto->enqueue(hu, skb);
+
+ hci_uart_tx_wakeup(hu);
+ return 0;
+}
+
+static void hci_uart_destruct(struct hci_dev *hdev)
+{
+ struct hci_uart *hu;
+
+ if (!hdev) return;
+
+ BT_DBG("%s", hdev->name);
+
+ hu = (struct hci_uart *) hdev->driver_data;
+ kfree(hu);
+}
+
+/* ------ LDISC part ------ */
+/* hci_uart_tty_open
+ *
+ * Called when line discipline changed to HCI_UART.
+ *
+ * Arguments:
+ * tty pointer to tty info structure
+ * Return Value:
+ * 0 if success, otherwise error code
+ */
+static int hci_uart_tty_open(struct tty_struct *tty)
+{
+ struct hci_uart *hu = (void *) tty->disc_data;
+
+ BT_DBG("tty %p", tty);
+
+ if (hu)
+ return -EEXIST;
+
+ if (!(hu = kmalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
+ BT_ERR("Can't allocate controll structure");
+ return -ENFILE;
+ }
+ memset(hu, 0, sizeof(struct hci_uart));
+
+ tty->disc_data = hu;
+ hu->tty = tty;
+
+ spin_lock_init(&hu->rx_lock);
+
+ /* Flush any pending characters in the driver and line discipline. */
+ /* FIXME: why is this needed. Note don't use ldisc_ref here as the
+ open path is before the ldisc is referencable */
+ if (tty->ldisc.flush_buffer)
+ tty->ldisc.flush_buffer(tty);
+
+ if (tty->driver->flush_buffer)
+ tty->driver->flush_buffer(tty);
+
+ return 0;
+}
+
+/* hci_uart_tty_close()
+ *
+ * Called when the line discipline is changed to something
+ * else, the tty is closed, or the tty detects a hangup.
+ */
+static void hci_uart_tty_close(struct tty_struct *tty)
+{
+ struct hci_uart *hu = (void *)tty->disc_data;
+
+ BT_DBG("tty %p", tty);
+
+ /* Detach from the tty */
+ tty->disc_data = NULL;
+
+ if (hu) {
+ struct hci_dev *hdev = hu->hdev;
+ hci_uart_close(hdev);
+
+ if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
+ hu->proto->close(hu);
+ hci_unregister_dev(hdev);
+ hci_free_dev(hdev);
+ }
+ }
+}
+
+/* hci_uart_tty_wakeup()
+ *
+ * Callback for transmit wakeup. Called when low level
+ * device driver can accept more send data.
+ *
+ * Arguments: tty pointer to associated tty instance data
+ * Return Value: None
+ */
+static void hci_uart_tty_wakeup(struct tty_struct *tty)
+{
+ struct hci_uart *hu = (void *)tty->disc_data;
+
+ BT_DBG("");
+
+ if (!hu)
+ return;
+
+ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+
+ if (tty != hu->tty)
+ return;
+
+ if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
+ hci_uart_tx_wakeup(hu);
+}
+
+/* hci_uart_tty_room()
+ *
+ * Callback function from tty driver. Return the amount of
+ * space left in the receiver's buffer to decide if remote
+ * transmitter is to be throttled.
+ *
+ * Arguments: tty pointer to associated tty instance data
+ * Return Value: number of bytes left in receive buffer
+ */
+static int hci_uart_tty_room (struct tty_struct *tty)
+{
+ return 65536;
+}
+
+/* hci_uart_tty_receive()
+ *
+ * Called by tty low level driver when receive data is
+ * available.
+ *
+ * Arguments: tty pointer to tty isntance data
+ * data pointer to received data
+ * flags pointer to flags for data
+ * count count of received data in bytes
+ *
+ * Return Value: None
+ */
+static void hci_uart_tty_receive(struct tty_struct *tty, const __u8 *data, char *flags, int count)
+{
+ struct hci_uart *hu = (void *)tty->disc_data;
+
+ if (!hu || tty != hu->tty)
+ return;
+
+ if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
+ return;
+
+ spin_lock(&hu->rx_lock);
+ hu->proto->recv(hu, (void *) data, count);
+ hu->hdev->stat.byte_rx += count;
+ spin_unlock(&hu->rx_lock);
+
+ if (test_and_clear_bit(TTY_THROTTLED,&tty->flags) && tty->driver->unthrottle)
+ tty->driver->unthrottle(tty);
+}
+
+static int hci_uart_register_dev(struct hci_uart *hu)
+{
+ struct hci_dev *hdev;
+
+ BT_DBG("");
+
+ /* Initialize and register HCI device */
+ hdev = hci_alloc_dev();
+ if (!hdev) {
+ BT_ERR("Can't allocate HCI device");
+ return -ENOMEM;
+ }
+
+ hu->hdev = hdev;
+
+ hdev->type = HCI_UART;
+ hdev->driver_data = hu;
+
+ hdev->open = hci_uart_open;
+ hdev->close = hci_uart_close;
+ hdev->flush = hci_uart_flush;
+ hdev->send = hci_uart_send_frame;
+ hdev->destruct = hci_uart_destruct;
+
+ hdev->owner = THIS_MODULE;
+
+ if (reset)
+ set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);
+
+ if (hci_register_dev(hdev) < 0) {
+ BT_ERR("Can't register HCI device");
+ hci_free_dev(hdev);
+ return -ENODEV;
+ }
+
+ return 0;
+}
+
+static int hci_uart_set_proto(struct hci_uart *hu, int id)
+{
+ struct hci_uart_proto *p;
+ int err;
+
+ p = hci_uart_get_proto(id);
+ if (!p)
+ return -EPROTONOSUPPORT;
+
+ err = p->open(hu);
+ if (err)
+ return err;
+
+ hu->proto = p;
+
+ err = hci_uart_register_dev(hu);
+ if (err) {
+ p->close(hu);
+ return err;
+ }
+ return 0;
+}
+
+/* hci_uart_tty_ioctl()
+ *
+ * Process IOCTL system call for the tty device.
+ *
+ * Arguments:
+ *
+ * tty pointer to tty instance data
+ * file pointer to open file object for device
+ * cmd IOCTL command code
+ * arg argument for IOCTL call (cmd dependent)
+ *
+ * Return Value: Command dependent
+ */
+static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
+ unsigned int cmd, unsigned long arg)
+{
+ struct hci_uart *hu = (void *)tty->disc_data;
+ int err = 0;
+
+ BT_DBG("");
+
+ /* Verify the status of the device */
+ if (!hu)
+ return -EBADF;
+
+ switch (cmd) {
+ case HCIUARTSETPROTO:
+ if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
+ err = hci_uart_set_proto(hu, arg);
+ if (err) {
+ clear_bit(HCI_UART_PROTO_SET, &hu->flags);
+ return err;
+ }
+ tty->low_latency = 1;
+ } else
+ return -EBUSY;
+
+ case HCIUARTGETPROTO:
+ if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
+ return hu->proto->id;
+ return -EUNATCH;
+
+ default:
+ err = n_tty_ioctl(tty, file, cmd, arg);
+ break;
+ };
+
+ return err;
+}
+
+/*
+ * We don't provide read/write/poll interface for user space.
+ */
+static ssize_t hci_uart_tty_read(struct tty_struct *tty, struct file *file, unsigned char __user *buf, size_t nr)
+{
+ return 0;
+}
+static ssize_t hci_uart_tty_write(struct tty_struct *tty, struct file *file, const unsigned char *data, size_t count)
+{
+ return 0;
+}
+static unsigned int hci_uart_tty_poll(struct tty_struct *tty, struct file *filp, poll_table *wait)
+{
+ return 0;
+}
+
+#ifdef CONFIG_BT_HCIUART_H4
+int h4_init(void);
+int h4_deinit(void);
+#endif
+#ifdef CONFIG_BT_HCIUART_BCSP
+int bcsp_init(void);
+int bcsp_deinit(void);
+#endif
+
+static int __init hci_uart_init(void)
+{
+ static struct tty_ldisc hci_uart_ldisc;
+ int err;
+
+ BT_INFO("HCI UART driver ver %s", VERSION);
+
+ /* Register the tty discipline */
+
+ memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
+ hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
+ hci_uart_ldisc.name = "n_hci";
+ hci_uart_ldisc.open = hci_uart_tty_open;
+ hci_uart_ldisc.close = hci_uart_tty_close;
+ hci_uart_ldisc.read = hci_uart_tty_read;
+ hci_uart_ldisc.write = hci_uart_tty_write;
+ hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
+ hci_uart_ldisc.poll = hci_uart_tty_poll;
+ hci_uart_ldisc.receive_room= hci_uart_tty_room;
+ hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
+ hci_uart_ldisc.write_wakeup= hci_uart_tty_wakeup;
+ hci_uart_ldisc.owner = THIS_MODULE;
+
+ if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
+ BT_ERR("HCI line discipline registration failed. (%d)", err);
+ return err;
+ }
+
+#ifdef CONFIG_BT_HCIUART_H4
+ h4_init();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCSP
+ bcsp_init();
+#endif
+
+ return 0;
+}
+
+static void __exit hci_uart_exit(void)
+{
+ int err;
+
+#ifdef CONFIG_BT_HCIUART_H4
+ h4_deinit();
+#endif
+#ifdef CONFIG_BT_HCIUART_BCSP
+ bcsp_deinit();
+#endif
+
+ /* Release tty registration of line discipline */
+ if ((err = tty_register_ldisc(N_HCI, NULL)))
+ BT_ERR("Can't unregister HCI line discipline (%d)", err);
+}
+
+module_init(hci_uart_init);
+module_exit(hci_uart_exit);
+
+module_param(reset, bool, 0644);
+MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
+
+MODULE_AUTHOR("Maxim Krasnyansky <maxk@qualcomm.com>, Marcel Holtmann <marcel@holtmann.org>");
+MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
+MODULE_VERSION(VERSION);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_LDISC(N_HCI);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.