[mirror_ubuntu-zesty-kernel.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/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... )
#endif

#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->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, 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);
	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, 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)
{
	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 = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
		BT_ERR("Can't allocate controll structure");
		return -ENFILE;
	}

	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;
}

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_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("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);
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 LT	25
	26	#include <linux/config.h>
	27	#include <linux/module.h>
	28
	29	#include <linux/kernel.h>
	30	#include <linux/init.h>
	31	#include <linux/sched.h>
	32	#include <linux/types.h>
	33	#include <linux/fcntl.h>
	34	#include <linux/interrupt.h>
	35	#include <linux/ptrace.h>
	36	#include <linux/poll.h>
	37
	38	#include <linux/slab.h>
	39	#include <linux/tty.h>
	40	#include <linux/errno.h>
	41	#include <linux/string.h>
	42	#include <linux/signal.h>
	43	#include <linux/ioctl.h>
	44	#include <linux/skbuff.h>
	45
	46	#include <net/bluetooth/bluetooth.h>
	47	#include <net/bluetooth/hci_core.h>
	48
	49	#include "hci_uart.h"
	50
	51	#ifndef CONFIG_BT_HCIUART_DEBUG
	52	#undef BT_DBG
	53	#define BT_DBG( A... )
1da177e4 LT	54	#endif
1da177e4 LT	55
0372a662 MH	56	#define VERSION "2.2"
0372a662 MH	57
1da177e4 LT	58	static int reset = 0;
	59
	60	static struct hci_uart_proto *hup[HCI_UART_MAX_PROTO];
	61
	62	int hci_uart_register_proto(struct hci_uart_proto *p)
	63	{
	64	if (p->id >= HCI_UART_MAX_PROTO)
	65	return -EINVAL;
	66
	67	if (hup[p->id])
	68	return -EEXIST;
	69
	70	hup[p->id] = p;
0372a662	71
1da177e4 LT	72	return 0;
	73	}
	74
	75	int hci_uart_unregister_proto(struct hci_uart_proto *p)
	76	{
	77	if (p->id >= HCI_UART_MAX_PROTO)
	78	return -EINVAL;
	79
	80	if (!hup[p->id])
	81	return -EINVAL;
	82
	83	hup[p->id] = NULL;
0372a662	84
1da177e4 LT	85	return 0;
	86	}
	87
	88	static struct hci_uart_proto *hci_uart_get_proto(unsigned int id)
	89	{
	90	if (id >= HCI_UART_MAX_PROTO)
	91	return NULL;
0372a662	92
1da177e4 LT	93	return hup[id];
	94	}
	95
	96	static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
	97	{
	98	struct hci_dev *hdev = hu->hdev;
0372a662	99
1da177e4 LT	100	/* Update HCI stat counters */
	101	switch (pkt_type) {
	102	case HCI_COMMAND_PKT:
	103	hdev->stat.cmd_tx++;
	104	break;
	105
	106	case HCI_ACLDATA_PKT:
	107	hdev->stat.acl_tx++;
	108	break;
	109
	110	case HCI_SCODATA_PKT:
	111	hdev->stat.cmd_tx++;
	112	break;
	113	}
	114	}
	115
	116	static inline struct sk_buff hci_uart_dequeue(struct hci_uart hu)
	117	{
	118	struct sk_buff *skb = hu->tx_skb;
0372a662	119
1da177e4 LT	120	if (!skb)
	121	skb = hu->proto->dequeue(hu);
	122	else
	123	hu->tx_skb = NULL;
0372a662	124
1da177e4 LT	125	return skb;
	126	}
	127
	128	int hci_uart_tx_wakeup(struct hci_uart *hu)
	129	{
	130	struct tty_struct *tty = hu->tty;
	131	struct hci_dev *hdev = hu->hdev;
	132	struct sk_buff *skb;
0372a662	133
1da177e4 LT	134	if (test_and_set_bit(HCI_UART_SENDING, &hu->tx_state)) {
	135	set_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	136	return 0;
	137	}
	138
	139	BT_DBG("");
	140
	141	restart:
	142	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	143
	144	while ((skb = hci_uart_dequeue(hu))) {
	145	int len;
0372a662	146
1da177e4 LT	147	set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	148	len = tty->driver->write(tty, skb->data, skb->len);
	149	hdev->stat.byte_tx += len;
	150
	151	skb_pull(skb, len);
	152	if (skb->len) {
	153	hu->tx_skb = skb;
	154	break;
	155	}
0372a662	156
0d48d939	157	hci_uart_tx_complete(hu, bt_cb(skb)->pkt_type);
1da177e4	158	kfree_skb(skb);
0372a662 MH	159	}
0372a662 MH	160
1da177e4 LT	161	if (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state))
	162	goto restart;
	163
	164	clear_bit(HCI_UART_SENDING, &hu->tx_state);
	165	return 0;
	166	}
	167
	168	/* ------- Interface to HCI layer ------ */
	169	/* Initialize device */
	170	static int hci_uart_open(struct hci_dev *hdev)
	171	{
	172	BT_DBG("%s %p", hdev->name, hdev);
	173
	174	/* Nothing to do for UART driver */
	175
	176	set_bit(HCI_RUNNING, &hdev->flags);
0372a662	177
1da177e4 LT	178	return 0;
	179	}
	180
	181	/* Reset device */
	182	static int hci_uart_flush(struct hci_dev *hdev)
	183	{
	184	struct hci_uart hu = (struct hci_uart ) hdev->driver_data;
	185	struct tty_struct *tty = hu->tty;
	186
	187	BT_DBG("hdev %p tty %p", hdev, tty);
	188
	189	if (hu->tx_skb) {
	190	kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	191	}
	192
	193	/* Flush any pending characters in the driver and discipline. */
	194	tty_ldisc_flush(tty);
	195	if (tty->driver->flush_buffer)
	196	tty->driver->flush_buffer(tty);
	197
	198	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	199	hu->proto->flush(hu);
	200
	201	return 0;
	202	}
	203
	204	/* Close device */
	205	static int hci_uart_close(struct hci_dev *hdev)
	206	{
	207	BT_DBG("hdev %p", hdev);
	208
	209	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
	210	return 0;
	211
	212	hci_uart_flush(hdev);
	213	return 0;
	214	}
	215
	216	/* Send frames from HCI layer */
	217	static int hci_uart_send_frame(struct sk_buff *skb)
	218	{
	219	struct hci_dev* hdev = (struct hci_dev *) skb->dev;
	220	struct tty_struct *tty;
	221	struct hci_uart *hu;
	222
	223	if (!hdev) {
	224	BT_ERR("Frame for uknown device (hdev=NULL)");
	225	return -ENODEV;
	226	}
	227
	228	if (!test_bit(HCI_RUNNING, &hdev->flags))
	229	return -EBUSY;
	230
	231	hu = (struct hci_uart *) hdev->driver_data;
	232	tty = hu->tty;
	233
0d48d939	234	BT_DBG("%s: type %d len %d", hdev->name, bt_cb(skb)->pkt_type, skb->len);
1da177e4 LT	235
	236	hu->proto->enqueue(hu, skb);
	237
	238	hci_uart_tx_wakeup(hu);
0372a662	239
1da177e4 LT	240	return 0;
	241	}
	242
	243	static void hci_uart_destruct(struct hci_dev *hdev)
	244	{
	245	struct hci_uart *hu;
	246
0372a662 MH	247	if (!hdev)
0372a662 MH	248	return;
1da177e4 LT	249
	250	BT_DBG("%s", hdev->name);
	251
	252	hu = (struct hci_uart *) hdev->driver_data;
	253	kfree(hu);
	254	}
	255
	256	/* ------ LDISC part ------ */
	257	/* hci_uart_tty_open
	258	*
	259	* Called when line discipline changed to HCI_UART.
	260	*
	261	* Arguments:
	262	* tty pointer to tty info structure
	263	* Return Value:
	264	* 0 if success, otherwise error code
	265	*/
	266	static int hci_uart_tty_open(struct tty_struct *tty)
	267	{
	268	struct hci_uart hu = (void ) tty->disc_data;
	269
	270	BT_DBG("tty %p", tty);
	271
	272	if (hu)
	273	return -EEXIST;
	274
089b1dbb	275	if (!(hu = kzalloc(sizeof(struct hci_uart), GFP_KERNEL))) {
1da177e4 LT	276	BT_ERR("Can't allocate controll structure");
	277	return -ENFILE;
	278	}
0372a662	279
1da177e4 LT	280	tty->disc_data = hu;
	281	hu->tty = tty;
	282
	283	spin_lock_init(&hu->rx_lock);
	284
	285	/* Flush any pending characters in the driver and line discipline. */
0372a662	286
1da177e4 LT	287	/* FIXME: why is this needed. Note don't use ldisc_ref here as the
1da177e4 LT	288	open path is before the ldisc is referencable */
0372a662	289
1da177e4 LT	290	if (tty->ldisc.flush_buffer)
	291	tty->ldisc.flush_buffer(tty);
	292
	293	if (tty->driver->flush_buffer)
	294	tty->driver->flush_buffer(tty);
	295
	296	return 0;
	297	}
	298
	299	/* hci_uart_tty_close()
	300	*
	301	* Called when the line discipline is changed to something
	302	* else, the tty is closed, or the tty detects a hangup.
	303	*/
	304	static void hci_uart_tty_close(struct tty_struct *tty)
	305	{
	306	struct hci_uart hu = (void )tty->disc_data;
	307
	308	BT_DBG("tty %p", tty);
	309
	310	/* Detach from the tty */
	311	tty->disc_data = NULL;
	312
	313	if (hu) {
	314	struct hci_dev *hdev = hu->hdev;
	315	hci_uart_close(hdev);
	316
	317	if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) {
	318	hu->proto->close(hu);
	319	hci_unregister_dev(hdev);
	320	hci_free_dev(hdev);
	321	}
	322	}
	323	}
	324
	325	/* hci_uart_tty_wakeup()
	326	*
	327	* Callback for transmit wakeup. Called when low level
	328	* device driver can accept more send data.
	329	*
	330	* Arguments: tty pointer to associated tty instance data
	331	* Return Value: None
	332	*/
	333	static void hci_uart_tty_wakeup(struct tty_struct *tty)
	334	{
	335	struct hci_uart hu = (void )tty->disc_data;
	336
	337	BT_DBG("");
	338
	339	if (!hu)
	340	return;
	341
	342	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	343
	344	if (tty != hu->tty)
	345	return;
	346
	347	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	348	hci_uart_tx_wakeup(hu);
	349	}
	350
	351	/* hci_uart_tty_room()
	352	*
	353	* Callback function from tty driver. Return the amount of
354	* space left in the receiver's buffer to decide if remote
355	* transmitter is to be throttled.
356	*
357	* Arguments: tty pointer to associated tty instance data
358	* Return Value: number of bytes left in receive buffer
359	*/
360	static int hci_uart_tty_room (struct tty_struct *tty)
361	{
362	return 65536;
363	}
364
365	/* hci_uart_tty_receive()
366	*
367	* Called by tty low level driver when receive data is
368	* available.
369	*
370	* Arguments: tty pointer to tty isntance data
371	* data pointer to received data
372	* flags pointer to flags for data
373	* count count of received data in bytes
374	*
375	* Return Value: None
376	*/
377	static void hci_uart_tty_receive(struct tty_struct tty, const __u8 data, char *flags, int count)
378	{
379	struct hci_uart hu = (void )tty->disc_data;
0372a662	380
1da177e4 LT	381	if (!hu \|\| tty != hu->tty)
	382	return;
	383
	384	if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
	385	return;
0372a662	386
1da177e4 LT	387	spin_lock(&hu->rx_lock);
	388	hu->proto->recv(hu, (void *) data, count);
	389	hu->hdev->stat.byte_rx += count;
	390	spin_unlock(&hu->rx_lock);
	391
	392	if (test_and_clear_bit(TTY_THROTTLED,&tty->flags) && tty->driver->unthrottle)
	393	tty->driver->unthrottle(tty);
	394	}
	395
	396	static int hci_uart_register_dev(struct hci_uart *hu)
	397	{
	398	struct hci_dev *hdev;
	399
	400	BT_DBG("");
	401
	402	/* Initialize and register HCI device */
	403	hdev = hci_alloc_dev();
	404	if (!hdev) {
	405	BT_ERR("Can't allocate HCI device");
	406	return -ENOMEM;
	407	}
	408
	409	hu->hdev = hdev;
	410
	411	hdev->type = HCI_UART;
	412	hdev->driver_data = hu;
	413
	414	hdev->open = hci_uart_open;
	415	hdev->close = hci_uart_close;
	416	hdev->flush = hci_uart_flush;
	417	hdev->send = hci_uart_send_frame;
	418	hdev->destruct = hci_uart_destruct;
	419
	420	hdev->owner = THIS_MODULE;
	421
	422	if (reset)
	423	set_bit(HCI_QUIRK_RESET_ON_INIT, &hdev->quirks);
	424
	425	if (hci_register_dev(hdev) < 0) {
	426	BT_ERR("Can't register HCI device");
	427	hci_free_dev(hdev);
	428	return -ENODEV;
	429	}
	430
	431	return 0;
	432	}
	433
	434	static int hci_uart_set_proto(struct hci_uart *hu, int id)
	435	{
	436	struct hci_uart_proto *p;
0372a662 MH	437	int err;
0372a662 MH	438
1da177e4 LT	439	p = hci_uart_get_proto(id);
	440	if (!p)
	441	return -EPROTONOSUPPORT;
	442
	443	err = p->open(hu);
	444	if (err)
	445	return err;
	446
	447	hu->proto = p;
	448
	449	err = hci_uart_register_dev(hu);
	450	if (err) {
	451	p->close(hu);
	452	return err;
	453	}
0372a662	454
1da177e4 LT	455	return 0;
	456	}
	457
	458	/* hci_uart_tty_ioctl()
	459	*
	460	* Process IOCTL system call for the tty device.
	461	*
	462	* Arguments:
	463	*
	464	* tty pointer to tty instance data
	465	* file pointer to open file object for device
	466	* cmd IOCTL command code
	467	* arg argument for IOCTL call (cmd dependent)
	468	*
	469	* Return Value: Command dependent
	470	*/
	471	static int hci_uart_tty_ioctl(struct tty_struct tty, struct file file,
0372a662	472	unsigned int cmd, unsigned long arg)
1da177e4 LT	473	{
	474	struct hci_uart hu = (void )tty->disc_data;
	475	int err = 0;
	476
	477	BT_DBG("");
	478
	479	/* Verify the status of the device */
	480	if (!hu)
	481	return -EBADF;
	482
	483	switch (cmd) {
	484	case HCIUARTSETPROTO:
	485	if (!test_and_set_bit(HCI_UART_PROTO_SET, &hu->flags)) {
	486	err = hci_uart_set_proto(hu, arg);
	487	if (err) {
	488	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
	489	return err;
	490	}
	491	tty->low_latency = 1;
0372a662	492	} else
1da177e4 LT	493	return -EBUSY;
	494
	495	case HCIUARTGETPROTO:
	496	if (test_bit(HCI_UART_PROTO_SET, &hu->flags))
	497	return hu->proto->id;
	498	return -EUNATCH;
0372a662	499
1da177e4 LT	500	default:
	501	err = n_tty_ioctl(tty, file, cmd, arg);
	502	break;
	503	};
	504
	505	return err;
	506	}
	507
	508	/*
	509	* We don't provide read/write/poll interface for user space.
	510	*/
0372a662 MH	511	static ssize_t hci_uart_tty_read(struct tty_struct tty, struct file file,
0372a662 MH	512	unsigned char __user *buf, size_t nr)
1da177e4 LT	513	{
	514	return 0;
	515	}
0372a662 MH	516
	517	static ssize_t hci_uart_tty_write(struct tty_struct tty, struct file file,
	518	const unsigned char *data, size_t count)
1da177e4 LT	519	{
	520	return 0;
	521	}
0372a662 MH	522
	523	static unsigned int hci_uart_tty_poll(struct tty_struct *tty,
	524	struct file filp, poll_table wait)
1da177e4 LT	525	{
	526	return 0;
	527	}
	528
1da177e4 LT	529	static int __init hci_uart_init(void)
	530	{
	531	static struct tty_ldisc hci_uart_ldisc;
	532	int err;
	533
	534	BT_INFO("HCI UART driver ver %s", VERSION);
	535
	536	/* Register the tty discipline */
	537
	538	memset(&hci_uart_ldisc, 0, sizeof (hci_uart_ldisc));
0372a662 MH	539	hci_uart_ldisc.magic = TTY_LDISC_MAGIC;
	540	hci_uart_ldisc.name = "n_hci";
	541	hci_uart_ldisc.open = hci_uart_tty_open;
	542	hci_uart_ldisc.close = hci_uart_tty_close;
	543	hci_uart_ldisc.read = hci_uart_tty_read;
	544	hci_uart_ldisc.write = hci_uart_tty_write;
	545	hci_uart_ldisc.ioctl = hci_uart_tty_ioctl;
	546	hci_uart_ldisc.poll = hci_uart_tty_poll;
	547	hci_uart_ldisc.receive_room = hci_uart_tty_room;
	548	hci_uart_ldisc.receive_buf = hci_uart_tty_receive;
	549	hci_uart_ldisc.write_wakeup = hci_uart_tty_wakeup;
	550	hci_uart_ldisc.owner = THIS_MODULE;
1da177e4 LT	551
	552	if ((err = tty_register_ldisc(N_HCI, &hci_uart_ldisc))) {
	553	BT_ERR("HCI line discipline registration failed. (%d)", err);
	554	return err;
	555	}
	556
	557	#ifdef CONFIG_BT_HCIUART_H4
	558	h4_init();
	559	#endif
	560	#ifdef CONFIG_BT_HCIUART_BCSP
	561	bcsp_init();
	562	#endif
	563
	564	return 0;
	565	}
	566
	567	static void __exit hci_uart_exit(void)
	568	{
	569	int err;
	570
	571	#ifdef CONFIG_BT_HCIUART_H4
	572	h4_deinit();
	573	#endif
	574	#ifdef CONFIG_BT_HCIUART_BCSP
	575	bcsp_deinit();
	576	#endif
	577
	578	/* Release tty registration of line discipline */
64ccd715	579	if ((err = tty_unregister_ldisc(N_HCI)))
1da177e4 LT	580	BT_ERR("Can't unregister HCI line discipline (%d)", err);
	581	}
	582
	583	module_init(hci_uart_init);
	584	module_exit(hci_uart_exit);
	585
	586	module_param(reset, bool, 0644);
	587	MODULE_PARM_DESC(reset, "Send HCI reset command on initialization");
	588
	589	MODULE_AUTHOR("Maxim Krasnyansky <maxk@qualcomm.com>, Marcel Holtmann <marcel@holtmann.org>");
	590	MODULE_DESCRIPTION("Bluetooth HCI UART driver ver " VERSION);
	591	MODULE_VERSION(VERSION);
	592	MODULE_LICENSE("GPL");
	593	MODULE_ALIAS_LDISC(N_HCI);