[linux.git] / drivers / bluetooth / hci_ll.c

/*
 *  Texas Instruments' Bluetooth HCILL UART protocol
 *
 *  HCILL (HCI Low Level) is a Texas Instruments' power management
 *  protocol extension to H4.
 *
 *  Copyright (C) 2007 Texas Instruments, Inc.
 *
 *  Written by Ohad Ben-Cohen <[email protected]>
 *
 *  Acknowledgements:
 *  This file is based on hci_h4.c, which was written
 *  by Maxim Krasnyansky and Marcel Holtmann.
 *
 *  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
 *
 *  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/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"

/* HCILL commands */
#define HCILL_GO_TO_SLEEP_IND	0x30
#define HCILL_GO_TO_SLEEP_ACK	0x31
#define HCILL_WAKE_UP_IND	0x32
#define HCILL_WAKE_UP_ACK	0x33

/* HCILL receiver States */
#define HCILL_W4_PACKET_TYPE	0
#define HCILL_W4_EVENT_HDR	1
#define HCILL_W4_ACL_HDR	2
#define HCILL_W4_SCO_HDR	3
#define HCILL_W4_DATA		4

/* HCILL states */
enum hcill_states_e {
	HCILL_ASLEEP,
	HCILL_ASLEEP_TO_AWAKE,
	HCILL_AWAKE,
	HCILL_AWAKE_TO_ASLEEP
};

struct hcill_cmd {
	u8 cmd;
} __packed;

struct ll_struct {
	unsigned long rx_state;
	unsigned long rx_count;
	struct sk_buff *rx_skb;
	struct sk_buff_head txq;
	spinlock_t hcill_lock;		/* HCILL state lock	*/
	unsigned long hcill_state;	/* HCILL power state	*/
	struct sk_buff_head tx_wait_q;	/* HCILL wait queue	*/
};

/*
 * Builds and sends an HCILL command packet.
 * These are very simple packets with only 1 cmd byte
 */
static int send_hcill_cmd(u8 cmd, struct hci_uart *hu)
{
	int err = 0;
	struct sk_buff *skb = NULL;
	struct ll_struct *ll = hu->priv;
	struct hcill_cmd *hcill_packet;

	BT_DBG("hu %p cmd 0x%x", hu, cmd);

	/* allocate packet */
	skb = bt_skb_alloc(1, GFP_ATOMIC);
	if (!skb) {
		BT_ERR("cannot allocate memory for HCILL packet");
		err = -ENOMEM;
		goto out;
	}

	/* prepare packet */
	hcill_packet = (struct hcill_cmd *) skb_put(skb, 1);
	hcill_packet->cmd = cmd;

	/* send packet */
	skb_queue_tail(&ll->txq, skb);
out:
	return err;
}

/* Initialize protocol */
static int ll_open(struct hci_uart *hu)
{
	struct ll_struct *ll;

	BT_DBG("hu %p", hu);

	ll = kzalloc(sizeof(*ll), GFP_KERNEL);
	if (!ll)
		return -ENOMEM;

	skb_queue_head_init(&ll->txq);
	skb_queue_head_init(&ll->tx_wait_q);
	spin_lock_init(&ll->hcill_lock);

	ll->hcill_state = HCILL_AWAKE;

	hu->priv = ll;

	return 0;
}

/* Flush protocol data */
static int ll_flush(struct hci_uart *hu)
{
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p", hu);

	skb_queue_purge(&ll->tx_wait_q);
	skb_queue_purge(&ll->txq);

	return 0;
}

/* Close protocol */
static int ll_close(struct hci_uart *hu)
{
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p", hu);

	skb_queue_purge(&ll->tx_wait_q);
	skb_queue_purge(&ll->txq);

	kfree_skb(ll->rx_skb);

	hu->priv = NULL;

	kfree(ll);

	return 0;
}

/*
 * internal function, which does common work of the device wake up process:
 * 1. places all pending packets (waiting in tx_wait_q list) in txq list.
 * 2. changes internal state to HCILL_AWAKE.
 * Note: assumes that hcill_lock spinlock is taken,
 * shouldn't be called otherwise!
 */
static void __ll_do_awake(struct ll_struct *ll)
{
	struct sk_buff *skb = NULL;

	while ((skb = skb_dequeue(&ll->tx_wait_q)))
		skb_queue_tail(&ll->txq, skb);

	ll->hcill_state = HCILL_AWAKE;
}

/*
 * Called upon a wake-up-indication from the device
 */
static void ll_device_want_to_wakeup(struct hci_uart *hu)
{
	unsigned long flags;
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p", hu);

	/* lock hcill state */
	spin_lock_irqsave(&ll->hcill_lock, flags);

	switch (ll->hcill_state) {
	case HCILL_ASLEEP_TO_AWAKE:
		/*
		 * This state means that both the host and the BRF chip
		 * have simultaneously sent a wake-up-indication packet.
		 * Traditionally, in this case, receiving a wake-up-indication
		 * was enough and an additional wake-up-ack wasn't needed.
		 * This has changed with the BRF6350, which does require an
		 * explicit wake-up-ack. Other BRF versions, which do not
		 * require an explicit ack here, do accept it, thus it is
		 * perfectly safe to always send one.
		 */
		BT_DBG("dual wake-up-indication");
		/* deliberate fall-through - do not add break */
	case HCILL_ASLEEP:
		/* acknowledge device wake up */
		if (send_hcill_cmd(HCILL_WAKE_UP_ACK, hu) < 0) {
			BT_ERR("cannot acknowledge device wake up");
			goto out;
		}
		break;
	default:
		/* any other state is illegal */
		BT_ERR("received HCILL_WAKE_UP_IND in state %ld", ll->hcill_state);
		break;
	}

	/* send pending packets and change state to HCILL_AWAKE */
	__ll_do_awake(ll);

out:
	spin_unlock_irqrestore(&ll->hcill_lock, flags);

	/* actually send the packets */
	hci_uart_tx_wakeup(hu);
}

/*
 * Called upon a sleep-indication from the device
 */
static void ll_device_want_to_sleep(struct hci_uart *hu)
{
	unsigned long flags;
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p", hu);

	/* lock hcill state */
	spin_lock_irqsave(&ll->hcill_lock, flags);

	/* sanity check */
	if (ll->hcill_state != HCILL_AWAKE)
		BT_ERR("ERR: HCILL_GO_TO_SLEEP_IND in state %ld", ll->hcill_state);

	/* acknowledge device sleep */
	if (send_hcill_cmd(HCILL_GO_TO_SLEEP_ACK, hu) < 0) {
		BT_ERR("cannot acknowledge device sleep");
		goto out;
	}

	/* update state */
	ll->hcill_state = HCILL_ASLEEP;

out:
	spin_unlock_irqrestore(&ll->hcill_lock, flags);

	/* actually send the sleep ack packet */
	hci_uart_tx_wakeup(hu);
}

/*
 * Called upon wake-up-acknowledgement from the device
 */
static void ll_device_woke_up(struct hci_uart *hu)
{
	unsigned long flags;
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p", hu);

	/* lock hcill state */
	spin_lock_irqsave(&ll->hcill_lock, flags);

	/* sanity check */
	if (ll->hcill_state != HCILL_ASLEEP_TO_AWAKE)
		BT_ERR("received HCILL_WAKE_UP_ACK in state %ld", ll->hcill_state);

	/* send pending packets and change state to HCILL_AWAKE */
	__ll_do_awake(ll);

	spin_unlock_irqrestore(&ll->hcill_lock, flags);

	/* actually send the packets */
	hci_uart_tx_wakeup(hu);
}

/* Enqueue frame for transmittion (padding, crc, etc) */
/* may be called from two simultaneous tasklets */
static int ll_enqueue(struct hci_uart *hu, struct sk_buff *skb)
{
	unsigned long flags = 0;
	struct ll_struct *ll = hu->priv;

	BT_DBG("hu %p skb %p", hu, skb);

	/* Prepend skb with frame type */
	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);

	/* lock hcill state */
	spin_lock_irqsave(&ll->hcill_lock, flags);

	/* act according to current state */
	switch (ll->hcill_state) {
	case HCILL_AWAKE:
		BT_DBG("device awake, sending normally");
		skb_queue_tail(&ll->txq, skb);
		break;
	case HCILL_ASLEEP:
		BT_DBG("device asleep, waking up and queueing packet");
		/* save packet for later */
		skb_queue_tail(&ll->tx_wait_q, skb);
		/* awake device */
		if (send_hcill_cmd(HCILL_WAKE_UP_IND, hu) < 0) {
			BT_ERR("cannot wake up device");
			break;
		}
		ll->hcill_state = HCILL_ASLEEP_TO_AWAKE;
		break;
	case HCILL_ASLEEP_TO_AWAKE:
		BT_DBG("device waking up, queueing packet");
		/* transient state; just keep packet for later */
		skb_queue_tail(&ll->tx_wait_q, skb);
		break;
	default:
		BT_ERR("illegal hcill state: %ld (losing packet)", ll->hcill_state);
		kfree_skb(skb);
		break;
	}

	spin_unlock_irqrestore(&ll->hcill_lock, flags);

	return 0;
}

static inline int ll_check_data_len(struct hci_dev *hdev, struct ll_struct *ll, int len)
{
	int room = skb_tailroom(ll->rx_skb);

	BT_DBG("len %d room %d", len, room);

	if (!len) {
		hci_recv_frame(hdev, ll->rx_skb);
	} else if (len > room) {
		BT_ERR("Data length is too large");
		kfree_skb(ll->rx_skb);
	} else {
		ll->rx_state = HCILL_W4_DATA;
		ll->rx_count = len;
		return len;
	}

	ll->rx_state = HCILL_W4_PACKET_TYPE;
	ll->rx_skb   = NULL;
	ll->rx_count = 0;

	return 0;
}

/* Recv data */
static int ll_recv(struct hci_uart *hu, const void *data, int count)
{
	struct ll_struct *ll = hu->priv;
	const char *ptr;
	struct hci_event_hdr *eh;
	struct hci_acl_hdr   *ah;
	struct hci_sco_hdr   *sh;
	int len, type, dlen;

	BT_DBG("hu %p count %d rx_state %ld rx_count %ld", hu, count, ll->rx_state, ll->rx_count);

	ptr = data;
	while (count) {
		if (ll->rx_count) {
			len = min_t(unsigned int, ll->rx_count, count);
			memcpy(skb_put(ll->rx_skb, len), ptr, len);
			ll->rx_count -= len; count -= len; ptr += len;

			if (ll->rx_count)
				continue;

			switch (ll->rx_state) {
			case HCILL_W4_DATA:
				BT_DBG("Complete data");
				hci_recv_frame(hu->hdev, ll->rx_skb);

				ll->rx_state = HCILL_W4_PACKET_TYPE;
				ll->rx_skb = NULL;
				continue;

			case HCILL_W4_EVENT_HDR:
				eh = hci_event_hdr(ll->rx_skb);

				BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen);

				ll_check_data_len(hu->hdev, ll, eh->plen);
				continue;

			case HCILL_W4_ACL_HDR:
				ah = hci_acl_hdr(ll->rx_skb);
				dlen = __le16_to_cpu(ah->dlen);

				BT_DBG("ACL header: dlen %d", dlen);

				ll_check_data_len(hu->hdev, ll, dlen);
				continue;

			case HCILL_W4_SCO_HDR:
				sh = hci_sco_hdr(ll->rx_skb);

				BT_DBG("SCO header: dlen %d", sh->dlen);

				ll_check_data_len(hu->hdev, ll, sh->dlen);
				continue;
			}
		}

		/* HCILL_W4_PACKET_TYPE */
		switch (*ptr) {
		case HCI_EVENT_PKT:
			BT_DBG("Event packet");
			ll->rx_state = HCILL_W4_EVENT_HDR;
			ll->rx_count = HCI_EVENT_HDR_SIZE;
			type = HCI_EVENT_PKT;
			break;

		case HCI_ACLDATA_PKT:
			BT_DBG("ACL packet");
			ll->rx_state = HCILL_W4_ACL_HDR;
			ll->rx_count = HCI_ACL_HDR_SIZE;
			type = HCI_ACLDATA_PKT;
			break;

		case HCI_SCODATA_PKT:
			BT_DBG("SCO packet");
			ll->rx_state = HCILL_W4_SCO_HDR;
			ll->rx_count = HCI_SCO_HDR_SIZE;
			type = HCI_SCODATA_PKT;
			break;

		/* HCILL signals */
		case HCILL_GO_TO_SLEEP_IND:
			BT_DBG("HCILL_GO_TO_SLEEP_IND packet");
			ll_device_want_to_sleep(hu);
			ptr++; count--;
			continue;

		case HCILL_GO_TO_SLEEP_ACK:
			/* shouldn't happen */
			BT_ERR("received HCILL_GO_TO_SLEEP_ACK (in state %ld)", ll->hcill_state);
			ptr++; count--;
			continue;

		case HCILL_WAKE_UP_IND:
			BT_DBG("HCILL_WAKE_UP_IND packet");
			ll_device_want_to_wakeup(hu);
			ptr++; count--;
			continue;

		case HCILL_WAKE_UP_ACK:
			BT_DBG("HCILL_WAKE_UP_ACK packet");
			ll_device_woke_up(hu);
			ptr++; count--;
			continue;

		default:
			BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr);
			hu->hdev->stat.err_rx++;
			ptr++; count--;
			continue;
		}

		ptr++; count--;

		/* Allocate packet */
		ll->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
		if (!ll->rx_skb) {
			BT_ERR("Can't allocate mem for new packet");
			ll->rx_state = HCILL_W4_PACKET_TYPE;
			ll->rx_count = 0;
			return -ENOMEM;
		}

		bt_cb(ll->rx_skb)->pkt_type = type;
	}

	return count;
}

static struct sk_buff *ll_dequeue(struct hci_uart *hu)
{
	struct ll_struct *ll = hu->priv;
	return skb_dequeue(&ll->txq);
}

static const struct hci_uart_proto llp = {
	.id		= HCI_UART_LL,
	.name		= "LL",
	.open		= ll_open,
	.close		= ll_close,
	.recv		= ll_recv,
	.enqueue	= ll_enqueue,
	.dequeue	= ll_dequeue,
	.flush		= ll_flush,
};

int __init ll_init(void)
{
	return hci_uart_register_proto(&llp);
}

int __exit ll_deinit(void)
{
	return hci_uart_unregister_proto(&llp);
}
Commit	Line	Data
166d2f6a OBC	1	/*
	2	* Texas Instruments' Bluetooth HCILL UART protocol
	3	*
	4	* HCILL (HCI Low Level) is a Texas Instruments' power management
	5	* protocol extension to H4.
	6	*
	7	* Copyright (C) 2007 Texas Instruments, Inc.
	8	*
	9	* Written by Ohad Ben-Cohen <[email protected]>
	10	*
	11	* Acknowledgements:
	12	* This file is based on hci_h4.c, which was written
	13	* by Maxim Krasnyansky and Marcel Holtmann.
	14	*
	15	* This program is free software; you can redistribute it and/or modify
	16	* it under the terms of the GNU General Public License version 2
	17	* as published by the Free Software Foundation
	18	*
	19	* This program is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License
	25	* along with this program; if not, write to the Free Software
	26	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	27	*
	28	*/
	29
	30	#include <linux/module.h>
	31	#include <linux/kernel.h>
	32
	33	#include <linux/init.h>
	34	#include <linux/sched.h>
	35	#include <linux/types.h>
	36	#include <linux/fcntl.h>
	37	#include <linux/interrupt.h>
	38	#include <linux/ptrace.h>
	39	#include <linux/poll.h>
	40
	41	#include <linux/slab.h>
	42	#include <linux/tty.h>
	43	#include <linux/errno.h>
	44	#include <linux/string.h>
	45	#include <linux/signal.h>
	46	#include <linux/ioctl.h>
	47	#include <linux/skbuff.h>
	48
	49	#include <net/bluetooth/bluetooth.h>
	50	#include <net/bluetooth/hci_core.h>
	51
	52	#include "hci_uart.h"
	53
	54	/* HCILL commands */
	55	#define HCILL_GO_TO_SLEEP_IND 0x30
	56	#define HCILL_GO_TO_SLEEP_ACK 0x31
	57	#define HCILL_WAKE_UP_IND 0x32
	58	#define HCILL_WAKE_UP_ACK 0x33
	59
	60	/* HCILL receiver States */
	61	#define HCILL_W4_PACKET_TYPE 0
	62	#define HCILL_W4_EVENT_HDR 1
	63	#define HCILL_W4_ACL_HDR 2
	64	#define HCILL_W4_SCO_HDR 3
65	#define HCILL_W4_DATA 4
66
67	/* HCILL states */
68	enum hcill_states_e {
69	HCILL_ASLEEP,
70	HCILL_ASLEEP_TO_AWAKE,
71	HCILL_AWAKE,
72	HCILL_AWAKE_TO_ASLEEP
73	};
74
75	struct hcill_cmd {
76	u8 cmd;
81ca405a	77	} __packed;
166d2f6a OBC	78
	79	struct ll_struct {
	80	unsigned long rx_state;
	81	unsigned long rx_count;
	82	struct sk_buff *rx_skb;
	83	struct sk_buff_head txq;
	84	spinlock_t hcill_lock; /* HCILL state lock */
	85	unsigned long hcill_state; /* HCILL power state */
	86	struct sk_buff_head tx_wait_q; /* HCILL wait queue */
	87	};
	88
	89	/*
	90	* Builds and sends an HCILL command packet.
	91	* These are very simple packets with only 1 cmd byte
	92	*/
	93	static int send_hcill_cmd(u8 cmd, struct hci_uart *hu)
	94	{
	95	int err = 0;
	96	struct sk_buff *skb = NULL;
	97	struct ll_struct *ll = hu->priv;
	98	struct hcill_cmd *hcill_packet;
	99
	100	BT_DBG("hu %p cmd 0x%x", hu, cmd);
	101
	102	/* allocate packet */
	103	skb = bt_skb_alloc(1, GFP_ATOMIC);
	104	if (!skb) {
	105	BT_ERR("cannot allocate memory for HCILL packet");
	106	err = -ENOMEM;
	107	goto out;
	108	}
	109
	110	/* prepare packet */
	111	hcill_packet = (struct hcill_cmd *) skb_put(skb, 1);
	112	hcill_packet->cmd = cmd;
166d2f6a OBC	113
	114	/* send packet */
	115	skb_queue_tail(&ll->txq, skb);
	116	out:
	117	return err;
	118	}
	119
	120	/* Initialize protocol */
	121	static int ll_open(struct hci_uart *hu)
	122	{
	123	struct ll_struct *ll;
	124
	125	BT_DBG("hu %p", hu);
	126
9eb648c3	127	ll = kzalloc(sizeof(*ll), GFP_KERNEL);
166d2f6a OBC	128	if (!ll)
	129	return -ENOMEM;
	130
	131	skb_queue_head_init(&ll->txq);
	132	skb_queue_head_init(&ll->tx_wait_q);
	133	spin_lock_init(&ll->hcill_lock);
	134
	135	ll->hcill_state = HCILL_AWAKE;
	136
	137	hu->priv = ll;
	138
	139	return 0;
	140	}
	141
	142	/* Flush protocol data */
	143	static int ll_flush(struct hci_uart *hu)
	144	{
	145	struct ll_struct *ll = hu->priv;
	146
	147	BT_DBG("hu %p", hu);
	148
	149	skb_queue_purge(&ll->tx_wait_q);
	150	skb_queue_purge(&ll->txq);
	151
	152	return 0;
	153	}
	154
	155	/* Close protocol */
	156	static int ll_close(struct hci_uart *hu)
	157	{
	158	struct ll_struct *ll = hu->priv;
	159
	160	BT_DBG("hu %p", hu);
	161
	162	skb_queue_purge(&ll->tx_wait_q);
	163	skb_queue_purge(&ll->txq);
	164
b1fb0683	165	kfree_skb(ll->rx_skb);
166d2f6a OBC	166
	167	hu->priv = NULL;
	168
	169	kfree(ll);
	170
	171	return 0;
	172	}
	173
	174	/*
	175	* internal function, which does common work of the device wake up process:
	176	* 1. places all pending packets (waiting in tx_wait_q list) in txq list.
	177	* 2. changes internal state to HCILL_AWAKE.
	178	* Note: assumes that hcill_lock spinlock is taken,
	179	* shouldn't be called otherwise!
	180	*/
	181	static void __ll_do_awake(struct ll_struct *ll)
	182	{
	183	struct sk_buff *skb = NULL;
	184
	185	while ((skb = skb_dequeue(&ll->tx_wait_q)))
	186	skb_queue_tail(&ll->txq, skb);
	187
	188	ll->hcill_state = HCILL_AWAKE;
	189	}
	190
	191	/*
	192	* Called upon a wake-up-indication from the device
	193	*/
	194	static void ll_device_want_to_wakeup(struct hci_uart *hu)
	195	{
	196	unsigned long flags;
	197	struct ll_struct *ll = hu->priv;
	198
	199	BT_DBG("hu %p", hu);
	200
	201	/* lock hcill state */
	202	spin_lock_irqsave(&ll->hcill_lock, flags);
	203
	204	switch (ll->hcill_state) {
5c548226 OBC	205	case HCILL_ASLEEP_TO_AWAKE:
	206	/*
	207	* This state means that both the host and the BRF chip
	208	* have simultaneously sent a wake-up-indication packet.
25985edc	209	* Traditionally, in this case, receiving a wake-up-indication
5c548226 OBC	210	* was enough and an additional wake-up-ack wasn't needed.
	211	* This has changed with the BRF6350, which does require an
	212	* explicit wake-up-ack. Other BRF versions, which do not
	213	* require an explicit ack here, do accept it, thus it is
	214	* perfectly safe to always send one.
	215	*/
	216	BT_DBG("dual wake-up-indication");
	217	/* deliberate fall-through - do not add break */
166d2f6a OBC	218	case HCILL_ASLEEP:
	219	/* acknowledge device wake up */
	220	if (send_hcill_cmd(HCILL_WAKE_UP_ACK, hu) < 0) {
	221	BT_ERR("cannot acknowledge device wake up");
	222	goto out;
	223	}
	224	break;
166d2f6a	225	default:
5c548226	226	/* any other state is illegal */
166d2f6a OBC	227	BT_ERR("received HCILL_WAKE_UP_IND in state %ld", ll->hcill_state);
	228	break;
	229	}
	230
	231	/* send pending packets and change state to HCILL_AWAKE */
	232	__ll_do_awake(ll);
	233
	234	out:
	235	spin_unlock_irqrestore(&ll->hcill_lock, flags);
	236
	237	/* actually send the packets */
	238	hci_uart_tx_wakeup(hu);
	239	}
	240
	241	/*
	242	* Called upon a sleep-indication from the device
	243	*/
	244	static void ll_device_want_to_sleep(struct hci_uart *hu)
	245	{
	246	unsigned long flags;
	247	struct ll_struct *ll = hu->priv;
	248
	249	BT_DBG("hu %p", hu);
	250
	251	/* lock hcill state */
	252	spin_lock_irqsave(&ll->hcill_lock, flags);
	253
	254	/* sanity check */
	255	if (ll->hcill_state != HCILL_AWAKE)
	256	BT_ERR("ERR: HCILL_GO_TO_SLEEP_IND in state %ld", ll->hcill_state);
	257
	258	/* acknowledge device sleep */
	259	if (send_hcill_cmd(HCILL_GO_TO_SLEEP_ACK, hu) < 0) {
	260	BT_ERR("cannot acknowledge device sleep");
	261	goto out;
	262	}
	263
	264	/* update state */
	265	ll->hcill_state = HCILL_ASLEEP;
	266
	267	out:
	268	spin_unlock_irqrestore(&ll->hcill_lock, flags);
	269
	270	/* actually send the sleep ack packet */
	271	hci_uart_tx_wakeup(hu);
	272	}
	273
	274	/*
	275	* Called upon wake-up-acknowledgement from the device
	276	*/
	277	static void ll_device_woke_up(struct hci_uart *hu)
	278	{
	279	unsigned long flags;
	280	struct ll_struct *ll = hu->priv;
	281
	282	BT_DBG("hu %p", hu);
	283
	284	/* lock hcill state */
	285	spin_lock_irqsave(&ll->hcill_lock, flags);
	286
	287	/* sanity check */
	288	if (ll->hcill_state != HCILL_ASLEEP_TO_AWAKE)
	289	BT_ERR("received HCILL_WAKE_UP_ACK in state %ld", ll->hcill_state);
	290
291	/* send pending packets and change state to HCILL_AWAKE */
292	__ll_do_awake(ll);
293
294	spin_unlock_irqrestore(&ll->hcill_lock, flags);
295
296	/* actually send the packets */
297	hci_uart_tx_wakeup(hu);
298	}
299
300	/* Enqueue frame for transmittion (padding, crc, etc) */
301	/* may be called from two simultaneous tasklets */
302	static int ll_enqueue(struct hci_uart hu, struct sk_buff skb)
303	{
304	unsigned long flags = 0;
305	struct ll_struct *ll = hu->priv;
306
307	BT_DBG("hu %p skb %p", hu, skb);
308
309	/* Prepend skb with frame type */
310	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
311
312	/* lock hcill state */
313	spin_lock_irqsave(&ll->hcill_lock, flags);
314
315	/* act according to current state */
316	switch (ll->hcill_state) {
317	case HCILL_AWAKE:
318	BT_DBG("device awake, sending normally");
319	skb_queue_tail(&ll->txq, skb);
320	break;
321	case HCILL_ASLEEP:
322	BT_DBG("device asleep, waking up and queueing packet");
323	/* save packet for later */
324	skb_queue_tail(&ll->tx_wait_q, skb);
325	/* awake device */
326	if (send_hcill_cmd(HCILL_WAKE_UP_IND, hu) < 0) {
327	BT_ERR("cannot wake up device");
328	break;
329	}
330	ll->hcill_state = HCILL_ASLEEP_TO_AWAKE;
331	break;
332	case HCILL_ASLEEP_TO_AWAKE:
333	BT_DBG("device waking up, queueing packet");
334	/* transient state; just keep packet for later */
335	skb_queue_tail(&ll->tx_wait_q, skb);
336	break;
337	default:
338	BT_ERR("illegal hcill state: %ld (losing packet)", ll->hcill_state);
339	kfree_skb(skb);
340	break;
341	}
342
343	spin_unlock_irqrestore(&ll->hcill_lock, flags);
344
345	return 0;
346	}
347
e1a26170	348	static inline int ll_check_data_len(struct hci_dev hdev, struct ll_struct ll, int len)
166d2f6a	349	{
fc5fef61	350	int room = skb_tailroom(ll->rx_skb);
166d2f6a OBC	351
	352	BT_DBG("len %d room %d", len, room);
	353
	354	if (!len) {
e1a26170	355	hci_recv_frame(hdev, ll->rx_skb);
166d2f6a OBC	356	} else if (len > room) {
	357	BT_ERR("Data length is too large");
	358	kfree_skb(ll->rx_skb);
	359	} else {
	360	ll->rx_state = HCILL_W4_DATA;
	361	ll->rx_count = len;
	362	return len;
	363	}
	364
	365	ll->rx_state = HCILL_W4_PACKET_TYPE;
	366	ll->rx_skb = NULL;
	367	ll->rx_count = 0;
	368
	369	return 0;
	370	}
	371
	372	/* Recv data */
9d1c40eb	373	static int ll_recv(struct hci_uart hu, const void data, int count)
166d2f6a OBC	374	{
166d2f6a OBC	375	struct ll_struct *ll = hu->priv;
9d1c40eb	376	const char *ptr;
166d2f6a OBC	377	struct hci_event_hdr *eh;
	378	struct hci_acl_hdr *ah;
	379	struct hci_sco_hdr *sh;
fc5fef61	380	int len, type, dlen;
166d2f6a OBC	381
	382	BT_DBG("hu %p count %d rx_state %ld rx_count %ld", hu, count, ll->rx_state, ll->rx_count);
	383
	384	ptr = data;
	385	while (count) {
	386	if (ll->rx_count) {
	387	len = min_t(unsigned int, ll->rx_count, count);
	388	memcpy(skb_put(ll->rx_skb, len), ptr, len);
	389	ll->rx_count -= len; count -= len; ptr += len;
	390
	391	if (ll->rx_count)
	392	continue;
	393
	394	switch (ll->rx_state) {
	395	case HCILL_W4_DATA:
	396	BT_DBG("Complete data");
e1a26170	397	hci_recv_frame(hu->hdev, ll->rx_skb);
166d2f6a OBC	398
	399	ll->rx_state = HCILL_W4_PACKET_TYPE;
	400	ll->rx_skb = NULL;
	401	continue;
	402
	403	case HCILL_W4_EVENT_HDR:
acce90d6	404	eh = hci_event_hdr(ll->rx_skb);
166d2f6a OBC	405
	406	BT_DBG("Event header: evt 0x%2.2x plen %d", eh->evt, eh->plen);
	407
e1a26170	408	ll_check_data_len(hu->hdev, ll, eh->plen);
166d2f6a OBC	409	continue;
	410
	411	case HCILL_W4_ACL_HDR:
acce90d6	412	ah = hci_acl_hdr(ll->rx_skb);
166d2f6a OBC	413	dlen = __le16_to_cpu(ah->dlen);
	414
	415	BT_DBG("ACL header: dlen %d", dlen);
	416
e1a26170	417	ll_check_data_len(hu->hdev, ll, dlen);
166d2f6a OBC	418	continue;
	419
	420	case HCILL_W4_SCO_HDR:
acce90d6	421	sh = hci_sco_hdr(ll->rx_skb);
166d2f6a OBC	422
	423	BT_DBG("SCO header: dlen %d", sh->dlen);
	424
e1a26170	425	ll_check_data_len(hu->hdev, ll, sh->dlen);
166d2f6a OBC	426	continue;
	427	}
	428	}
	429
	430	/* HCILL_W4_PACKET_TYPE */
	431	switch (*ptr) {
	432	case HCI_EVENT_PKT:
	433	BT_DBG("Event packet");
	434	ll->rx_state = HCILL_W4_EVENT_HDR;
	435	ll->rx_count = HCI_EVENT_HDR_SIZE;
	436	type = HCI_EVENT_PKT;
	437	break;
	438
	439	case HCI_ACLDATA_PKT:
	440	BT_DBG("ACL packet");
	441	ll->rx_state = HCILL_W4_ACL_HDR;
	442	ll->rx_count = HCI_ACL_HDR_SIZE;
	443	type = HCI_ACLDATA_PKT;
	444	break;
	445
	446	case HCI_SCODATA_PKT:
	447	BT_DBG("SCO packet");
	448	ll->rx_state = HCILL_W4_SCO_HDR;
	449	ll->rx_count = HCI_SCO_HDR_SIZE;
	450	type = HCI_SCODATA_PKT;
	451	break;
	452
	453	/* HCILL signals */
	454	case HCILL_GO_TO_SLEEP_IND:
	455	BT_DBG("HCILL_GO_TO_SLEEP_IND packet");
	456	ll_device_want_to_sleep(hu);
	457	ptr++; count--;
	458	continue;
	459
	460	case HCILL_GO_TO_SLEEP_ACK:
	461	/* shouldn't happen */
	462	BT_ERR("received HCILL_GO_TO_SLEEP_ACK (in state %ld)", ll->hcill_state);
	463	ptr++; count--;
	464	continue;
	465
	466	case HCILL_WAKE_UP_IND:
	467	BT_DBG("HCILL_WAKE_UP_IND packet");
	468	ll_device_want_to_wakeup(hu);
	469	ptr++; count--;
	470	continue;
	471
	472	case HCILL_WAKE_UP_ACK:
	473	BT_DBG("HCILL_WAKE_UP_ACK packet");
	474	ll_device_woke_up(hu);
	475	ptr++; count--;
	476	continue;
	477
	478	default:
	479	BT_ERR("Unknown HCI packet type %2.2x", (__u8)*ptr);
	480	hu->hdev->stat.err_rx++;
	481	ptr++; count--;
	482	continue;
d650ccae	483	}
166d2f6a OBC	484
	485	ptr++; count--;
	486
	487	/* Allocate packet */
	488	ll->rx_skb = bt_skb_alloc(HCI_MAX_FRAME_SIZE, GFP_ATOMIC);
	489	if (!ll->rx_skb) {
	490	BT_ERR("Can't allocate mem for new packet");
	491	ll->rx_state = HCILL_W4_PACKET_TYPE;
	492	ll->rx_count = 0;
fe1aff71	493	return -ENOMEM;
166d2f6a OBC	494	}
166d2f6a OBC	495
166d2f6a OBC	496	bt_cb(ll->rx_skb)->pkt_type = type;
	497	}
	498
	499	return count;
	500	}
	501
	502	static struct sk_buff ll_dequeue(struct hci_uart hu)
	503	{
	504	struct ll_struct *ll = hu->priv;
	505	return skb_dequeue(&ll->txq);
	506	}
	507
4ee7ef19	508	static const struct hci_uart_proto llp = {
166d2f6a	509	.id = HCI_UART_LL,
7c40fb8d	510	.name = "LL",
166d2f6a OBC	511	.open = ll_open,
	512	.close = ll_close,
	513	.recv = ll_recv,
	514	.enqueue = ll_enqueue,
	515	.dequeue = ll_dequeue,
	516	.flush = ll_flush,
	517	};
	518
f2b94bb9	519	int __init ll_init(void)
166d2f6a	520	{
01009eec	521	return hci_uart_register_proto(&llp);
166d2f6a OBC	522	}
166d2f6a OBC	523
f2b94bb9	524	int __exit ll_deinit(void)
166d2f6a OBC	525	{
	526	return hci_uart_unregister_proto(&llp);
	527	}