diff options
Diffstat (limited to 'drivers/bluetooth/hci_ldisc.c')
-rw-r--r-- | drivers/bluetooth/hci_ldisc.c | 593 |
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 0000000..9075bbb --- /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); |