[linux-2.6-block.git] / drivers / bluetooth / hci_ldisc.c

/*
 *
 *  Bluetooth HCI UART driver
 *
 *  Copyright (C) 2000-2001  Qualcomm Incorporated
 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 *  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.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/init.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"

#define VERSION "2.2"

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->ops->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, bt_cb(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);
	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);
	hdev->flush = NULL;
	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 unknown 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, bt_cb(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)
{
	if (!hdev)
		return;

	BT_DBG("%s", hdev->name);
	kfree(hdev->driver_data);
}

/* ------ 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 = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
		BT_ERR("Can't allocate control structure");
		return -ENFILE;
	}

	tty->disc_data = hu;
	hu->tty = tty;
	tty->receive_room = 65536;

	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->ops->flush_buffer)
		tty->ldisc->ops->flush_buffer(tty);
	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;

		if (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_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);

	tty_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->bus = 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_NO_RESET, &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;
			}
		} else
			return -EBUSY;
		break;

	case HCIUARTGETPROTO:
		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
			return hu->proto->id;
		return -EUNATCH;

	case HCIUARTGETDEVICE:
		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
			return hu->hdev->id;
		return -EUNATCH;

	default:
		err = n_tty_ioctl_helper(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;
}

static int __init hci_uart_init(void)
{
	static struct tty_ldisc_ops 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_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
#ifdef CONFIG_BT_HCIUART_LL
	ll_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
#ifdef CONFIG_BT_HCIUART_LL
	ll_deinit();
#endif

	/* Release tty registration of line discipline */
	if ((err = tty_unregister_ldisc(N_HCI)))
		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("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_ALIAS_LDISC(N_HCI);
Commit	Line	Data
1da177e4	1	/*
1da177e4	2	*
0372a662 MH	3	* Bluetooth HCI UART driver
	4	*
	5	* Copyright (C) 2000-2001 Qualcomm Incorporated
	6	* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
	7	* Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
	8	*
	9	*
	10	* This program is free software; you can redistribute it and/or modify
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software
	22	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*
1da177e4	24	*/
1da177e4	25
1da177e4 LT	26	#include <linux/module.h>
	27
	28	#include <linux/kernel.h>
	29	#include <linux/init.h>
1da177e4 LT	30	#include <linux/types.h>
	31	#include <linux/fcntl.h>
	32	#include <linux/interrupt.h>
	33	#include <linux/ptrace.h>
	34	#include <linux/poll.h>
	35
	36	#include <linux/slab.h>
	37	#include <linux/tty.h>
	38	#include <linux/errno.h>
	39	#include <linux/string.h>
	40	#include <linux/signal.h>
	41	#include <linux/ioctl.h>
	42	#include <linux/skbuff.h>
	43
	44	#include <net/bluetooth/bluetooth.h>
	45	#include <net/bluetooth/hci_core.h>
	46
	47	#include "hci_uart.h"
	48
0372a662 MH	49	#define VERSION "2.2"
0372a662 MH	50
1da177e4 LT	51	static int reset = 0;
	52
	53	static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
	54
	55	int hci_uart_register_proto(struct hci_uart_proto *p)
	56	{
	57	if (p->id >= HCI_UART_MAX_PROTO)
	58	return -EINVAL;
	59
	60	if (hup[p->id])
	61	return -EEXIST;
	62
	63	hup[p->id] = p;
0372a662	64
1da177e4 LT	65	return 0;
	66	}
	67
	68	int hci_uart_unregister_proto(struct hci_uart_proto *p)
	69	{
	70	if (p->id >= HCI_UART_MAX_PROTO)
	71	return -EINVAL;
	72
	73	if (!hup[p->id])
	74	return -EINVAL;
	75
	76	hup[p->id] = NULL;
0372a662	77
1da177e4 LT	78	return 0;
	79	}
	80
	81	static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
	82	{
	83	if (id >= HCI_UART_MAX_PROTO)
	84	return NULL;
0372a662	85
1da177e4 LT	86	return hup[id];
	87	}
	88
	89	static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
	90	{
	91	struct hci_dev *hdev = hu->hdev;
0372a662	92
1da177e4 LT	93	/* Update HCI stat counters */
	94	switch (pkt_type) {
	95	case HCI_COMMAND_PKT:
	96	hdev->stat.cmd_tx++;
	97	break;
	98
	99	case HCI_ACLDATA_PKT:
	100	hdev->stat.acl_tx++;
	101	break;
	102
	103	case HCI_SCODATA_PKT:
	104	hdev->stat.cmd_tx++;
	105	break;
	106	}
	107	}
	108
	109	static inline struct sk_buff hci_uart_dequeue(struct hci_uart hu)
	110	{
	111	struct sk_buff *skb = hu->tx_skb;
0372a662	112
1da177e4 LT	113	if (!skb)
	114	skb = hu->proto->dequeue(hu);
	115	else
	116	hu->tx_skb = NULL;
0372a662	117
1da177e4 LT	118	return skb;
	119	}
	120
	121	int hci_uart_tx_wakeup(struct hci_uart *hu)
	122	{
	123	struct tty_struct *tty = hu->tty;
	124	struct hci_dev *hdev = hu->hdev;
	125	struct sk_buff *skb;
0372a662	126
1da177e4 LT	127	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
	128	set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	129	return 0;
	130	}
	131
	132	BT_DBG("");
	133
	134	restart:
	135	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	136
	137	while ((skb = hci_uart_dequeue(hu))) {
	138	int len;
0372a662	139
1da177e4	140	set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
f34d7a5b	141	len = tty->ops->write(tty, skb->data, skb->len);
1da177e4 LT	142	hdev->stat.byte_tx += len;
	143
	144	skb_pull(skb, len);
	145	if (skb->len) {
	146	hu->tx_skb = skb;
	147	break;
	148	}
0372a662	149
0d48d939	150	hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
1da177e4	151	kfree_skb(skb);
0372a662 MH	152	}
0372a662 MH	153
1da177e4 LT	154	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
	155	goto restart;
	156
	157	clear_bit(HCI_UART_SENDING, &hu->tx_state);
	158	return 0;
	159	}
	160
	161	/* ------- Interface to HCI layer ------ */
	162	/* Initialize device */
	163	static int hci_uart_open(struct hci_dev *hdev)
	164	{
	165	BT_DBG("%s %p", hdev->name, hdev);
	166
	167	/* Nothing to do for UART driver */
	168
	169	set_bit(HCI_RUNNING, &hdev->flags);
0372a662	170
1da177e4 LT	171	return 0;
	172	}
	173
	174	/* Reset device */
	175	static int hci_uart_flush(struct hci_dev *hdev)
	176	{
	177	struct hci_uart hu = (struct hci_uart ) hdev->driver_data;
	178	struct tty_struct *tty = hu->tty;
	179
	180	BT_DBG("hdev %p tty %p", hdev, tty);
	181
	182	if (hu->tx_skb) {
	183	kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	184	}
	185
	186	/* Flush any pending characters in the driver and discipline. */
	187	tty_ldisc_flush(tty);
f34d7a5b	188	tty_driver_flush_buffer(tty);
1da177e4 LT	189
	190	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	191	hu->proto->flush(hu);
	192
	193	return 0;
	194	}
	195
	196	/* Close device */
	197	static int hci_uart_close(struct hci_dev *hdev)
	198	{
	199	BT_DBG("hdev %p", hdev);
	200
	201	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
	202	return 0;
	203
	204	hci_uart_flush(hdev);
3611f4d2	205	hdev->flush = NULL;
1da177e4 LT	206	return 0;
	207	}
	208
	209	/* Send frames from HCI layer */
	210	static int hci_uart_send_frame(struct sk_buff *skb)
	211	{
	212	struct hci_dev* hdev = (struct hci_dev *) skb->dev;
	213	struct tty_struct *tty;
	214	struct hci_uart *hu;
	215
	216	if (!hdev) {
af901ca1	217	BT_ERR("Frame for unknown device (hdev=NULL)");
1da177e4 LT	218	return -ENODEV;
	219	}
	220
	221	if (!test_bit(HCI_RUNNING, &hdev->flags))
	222	return -EBUSY;
	223
	224	hu = (struct hci_uart *) hdev->driver_data;
	225	tty = hu->tty;
	226
0d48d939	227	BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
1da177e4 LT	228
	229	hu->proto->enqueue(hu, skb);
	230
	231	hci_uart_tx_wakeup(hu);
0372a662	232
1da177e4 LT	233	return 0;
	234	}
	235
	236	static void hci_uart_destruct(struct hci_dev *hdev)
	237	{
0372a662 MH	238	if (!hdev)
0372a662 MH	239	return;
1da177e4 LT	240
1da177e4 LT	241	BT_DBG("%s", hdev->name);
7785162c	242	kfree(hdev->driver_data);
1da177e4 LT	243	}
	244
	245	/* ------ LDISC part ------ */
	246	/* hci_uart_tty_open
	247	*
	248	* Called when line discipline changed to HCI_UART.
	249	*
	250	* Arguments:
	251	* tty pointer to tty info structure
	252	* Return Value:
	253	* 0 if success, otherwise error code
	254	*/
	255	static int hci_uart_tty_open(struct tty_struct *tty)
	256	{
	257	struct hci_uart hu = (void ) tty->disc_data;
	258
	259	BT_DBG("tty %p", tty);
	260
	261	if (hu)
	262	return -EEXIST;
	263
089b1dbb	264	if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
7785162c	265	BT_ERR("Can't allocate control structure");
1da177e4 LT	266	return -ENFILE;
1da177e4 LT	267	}
0372a662	268
1da177e4 LT	269	tty->disc_data = hu;
1da177e4 LT	270	hu->tty = tty;
33f0f88f	271	tty->receive_room = 65536;
1da177e4 LT	272
	273	spin_lock_init(&hu->rx_lock);
	274
	275	/* Flush any pending characters in the driver and line discipline. */
0372a662	276
1da177e4 LT	277	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
1da177e4 LT	278	open path is before the ldisc is referencable */
0372a662	279
c65c9bc3 AC	280	if (tty->ldisc->ops->flush_buffer)
c65c9bc3 AC	281	tty->ldisc->ops->flush_buffer(tty);
f34d7a5b	282	tty_driver_flush_buffer(tty);
1da177e4 LT	283
	284	return 0;
	285	}
	286
	287	/* hci_uart_tty_close()
	288	*
	289	* Called when the line discipline is changed to something
	290	* else, the tty is closed, or the tty detects a hangup.
	291	*/
	292	static void hci_uart_tty_close(struct tty_struct *tty)
	293	{
	294	struct hci_uart hu = (void )tty->disc_data;
	295
	296	BT_DBG("tty %p", tty);
	297
	298	/* Detach from the tty */
	299	tty->disc_data = NULL;
	300
	301	if (hu) {
	302	struct hci_dev *hdev = hu->hdev;
22ad4203 MH	303
	304	if (hdev)
	305	hci_uart_close(hdev);
1da177e4 LT	306
	307	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
	308	hu->proto->close(hu);
	309	hci_unregister_dev(hdev);
	310	hci_free_dev(hdev);
	311	}
	312	}
	313	}
	314
	315	/* hci_uart_tty_wakeup()
	316	*
	317	* Callback for transmit wakeup. Called when low level
	318	* device driver can accept more send data.
	319	*
	320	* Arguments: tty pointer to associated tty instance data
	321	* Return Value: None
	322	*/
	323	static void hci_uart_tty_wakeup(struct tty_struct *tty)
	324	{
	325	struct hci_uart hu = (void )tty->disc_data;
	326
	327	BT_DBG("");
	328
	329	if (!hu)
	330	return;
	331
	332	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	333
	334	if (tty != hu->tty)
	335	return;
	336
	337	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	338	hci_uart_tx_wakeup(hu);
	339	}
	340
1da177e4 LT	341	/* hci_uart_tty_receive()
	342	*
	343	* Called by tty low level driver when receive data is
	344	* available.
	345	*
	346	* Arguments: tty pointer to tty isntance data
	347	* data pointer to received data
	348	* flags pointer to flags for data
	349	* count count of received data in bytes
	350	*
	351	* Return Value: None
	352	*/
7785162c	353	static void hci_uart_tty_receive(struct tty_struct tty, const u8 data, char *flags, int count)
1da177e4 LT	354	{
1da177e4 LT	355	struct hci_uart hu = (void )tty->disc_data;
0372a662	356
1da177e4 LT	357	if (!hu \|\| tty != hu->tty)
	358	return;
	359
	360	if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
	361	return;
0372a662	362
1da177e4 LT	363	spin_lock(&hu->rx_lock);
	364	hu->proto->recv(hu, (void *) data, count);
	365	hu->hdev->stat.byte_rx += count;
	366	spin_unlock(&hu->rx_lock);
	367
39c2e60f	368	tty_unthrottle(tty);
1da177e4 LT	369	}
	370
	371	static int hci_uart_register_dev(struct hci_uart *hu)
	372	{
	373	struct hci_dev *hdev;
	374
	375	BT_DBG("");
	376
	377	/* Initialize and register HCI device */
	378	hdev = hci_alloc_dev();
	379	if (!hdev) {
	380	BT_ERR("Can't allocate HCI device");
	381	return -ENOMEM;
	382	}
	383
	384	hu->hdev = hdev;
	385
c13854ce	386	hdev->bus = HCI_UART;
1da177e4 LT	387	hdev->driver_data = hu;
	388
	389	hdev->open = hci_uart_open;
	390	hdev->close = hci_uart_close;
	391	hdev->flush = hci_uart_flush;
	392	hdev->send = hci_uart_send_frame;
	393	hdev->destruct = hci_uart_destruct;
	394
	395	hdev->owner = THIS_MODULE;
	396
7a9d4020 MH	397	if (!reset)
7a9d4020 MH	398	set_bit(HCI_QUIRK_NO_RESET, &hdev->quirks);
1da177e4 LT	399
	400	if (hci_register_dev(hdev) < 0) {
	401	BT_ERR("Can't register HCI device");
	402	hci_free_dev(hdev);
	403	return -ENODEV;
	404	}
	405
	406	return 0;
	407	}
	408
	409	static int hci_uart_set_proto(struct hci_uart *hu, int id)
	410	{
	411	struct hci_uart_proto *p;
0372a662 MH	412	int err;
0372a662 MH	413
1da177e4 LT	414	p = hci_uart_get_proto(id);
	415	if (!p)
	416	return -EPROTONOSUPPORT;
	417
	418	err = p->open(hu);
	419	if (err)
	420	return err;
	421
	422	hu->proto = p;
	423
	424	err = hci_uart_register_dev(hu);
	425	if (err) {
	426	p->close(hu);
	427	return err;
	428	}
0372a662	429
1da177e4 LT	430	return 0;
	431	}
	432
	433	/* hci_uart_tty_ioctl()
	434	*
	435	* Process IOCTL system call for the tty device.
	436	*
	437	* Arguments:
	438	*
	439	* tty pointer to tty instance data
	440	* file pointer to open file object for device
	441	* cmd IOCTL command code
	442	* arg argument for IOCTL call (cmd dependent)
	443	*
	444	* Return Value: Command dependent
	445	*/
	446	static int hci_uart_tty_ioctl(struct tty_struct tty, struct file file,
0372a662	447	unsigned int cmd, unsigned long arg)
1da177e4 LT	448	{
	449	struct hci_uart hu = (void )tty->disc_data;
	450	int err = 0;
	451
	452	BT_DBG("");
	453
	454	/* Verify the status of the device */
	455	if (!hu)
	456	return -EBADF;
	457
	458	switch (cmd) {
	459	case HCIUARTSETPROTO:
	460	if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
	461	err = hci_uart_set_proto(hu, arg);
	462	if (err) {
	463	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
	464	return err;
	465	}
0372a662	466	} else
1da177e4	467	return -EBUSY;
c33be3c3	468	break;
1da177e4 LT	469
	470	case HCIUARTGETPROTO:
	471	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	472	return hu->proto->id;
	473	return -EUNATCH;
0372a662	474
d2158744 MH	475	case HCIUARTGETDEVICE:
	476	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	477	return hu->hdev->id;
	478	return -EUNATCH;
	479
1da177e4	480	default:
47afa7a5	481	err = n_tty_ioctl_helper(tty, file, cmd, arg);
1da177e4 LT	482	break;
	483	};
	484
	485	return err;
	486	}
	487
	488	/*
	489	* We don't provide read/write/poll interface for user space.
	490	*/
0372a662 MH	491	static ssize_t hci_uart_tty_read(struct tty_struct tty, struct file file,
0372a662 MH	492	unsigned char __user *buf, size_t nr)
1da177e4 LT	493	{
	494	return 0;
	495	}
0372a662 MH	496
	497	static ssize_t hci_uart_tty_write(struct tty_struct tty, struct file file,
	498	const unsigned char *data, size_t count)
1da177e4 LT	499	{
	500	return 0;
	501	}
0372a662 MH	502
	503	static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
	504	struct file filp, poll_table wait)
1da177e4 LT	505	{
	506	return 0;
	507	}
	508
1da177e4 LT	509	static int __init hci_uart_init(void)
1da177e4 LT	510	{
a352def2	511	static struct tty_ldisc_ops hci_uart_ldisc;
1da177e4 LT	512	int err;
	513
	514	BT_INFO("HCI UART driver ver %s", VERSION);
	515
	516	/* Register the tty discipline */
	517
	518	memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
0372a662 MH	519	hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
	520	hci_uart_ldisc.name = "n_hci";
	521	hci_uart_ldisc.open = hci_uart_tty_open;
	522	hci_uart_ldisc.close = hci_uart_tty_close;
	523	hci_uart_ldisc.read = hci_uart_tty_read;
	524	hci_uart_ldisc.write = hci_uart_tty_write;
	525	hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
	526	hci_uart_ldisc.poll = hci_uart_tty_poll;
0372a662 MH	527	hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
	528	hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
	529	hci_uart_ldisc.owner = THIS_MODULE;
1da177e4 LT	530
	531	if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
	532	BT_ERR("HCI line discipline registration failed. (%d)", err);
	533	return err;
	534	}
	535
	536	#ifdef CONFIG_BT_HCIUART_H4
	537	h4_init();
	538	#endif
	539	#ifdef CONFIG_BT_HCIUART_BCSP
	540	bcsp_init();
	541	#endif
166d2f6a OBC	542	#ifdef CONFIG_BT_HCIUART_LL
	543	ll_init();
	544	#endif
	545
1da177e4 LT	546	return 0;
	547	}
	548
	549	static void __exit hci_uart_exit(void)
	550	{
	551	int err;
	552
	553	#ifdef CONFIG_BT_HCIUART_H4
	554	h4_deinit();
	555	#endif
	556	#ifdef CONFIG_BT_HCIUART_BCSP
	557	bcsp_deinit();
	558	#endif
166d2f6a OBC	559	#ifdef CONFIG_BT_HCIUART_LL
	560	ll_deinit();
	561	#endif
1da177e4 LT	562
1da177e4 LT	563	/* Release tty registration of line discipline */
64ccd715	564	if ((err = tty_unregister_ldisc(N_HCI)))
1da177e4 LT	565	BT_ERR("Can't unregister HCI line discipline (%d)", err);
	566	}
	567
	568	module_init(hci_uart_init);
	569	module_exit(hci_uart_exit);
	570
	571	module_param(reset, bool, 0644);
	572	MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
	573
63fbd24e	574	MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
1da177e4 LT	575	MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
	576	MODULE_VERSION(VERSION);
	577	MODULE_LICENSE("GPL");
	578	MODULE_ALIAS_LDISC(N_HCI);