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

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  Bluetooth HCI serdev driver lib
 *
 *  Copyright (C) 2017  Linaro, Ltd., Rob Herring <robh@kernel.org>
 *
 *  Based on hci_ldisc.c:
 *
 *  Copyright (C) 2000-2001  Qualcomm Incorporated
 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2004-2005  Marcel Holtmann <marcel@holtmann.org>
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/serdev.h>
#include <linux/skbuff.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "hci_uart.h"

static struct serdev_device_ops hci_serdev_client_ops;

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.sco_tx++;
		break;
	}
}

static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu)
{
	struct sk_buff *skb = hu->tx_skb;

	if (!skb) {
		if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
			skb = hu->proto->dequeue(hu);
	} else
		hu->tx_skb = NULL;

	return skb;
}

static void hci_uart_write_work(struct work_struct *work)
{
	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
	struct serdev_device *serdev = hu->serdev;
	struct hci_dev *hdev = hu->hdev;
	struct sk_buff *skb;

	/* REVISIT:
	 * should we cope with bad skbs or ->write() returning an error value?
	 */
	do {
		clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);

		while ((skb = hci_uart_dequeue(hu))) {
			int len;

			len = serdev_device_write_buf(serdev,
						      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, hci_skb_pkt_type(skb));
			kfree_skb(skb);
		}
	} while (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state));

	clear_bit(HCI_UART_SENDING, &hu->tx_state);
}

/* ------- Interface to HCI layer ------ */

/* Reset device */
static int hci_uart_flush(struct hci_dev *hdev)
{
	struct hci_uart *hu  = hci_get_drvdata(hdev);

	BT_DBG("hdev %p serdev %p", hdev, hu->serdev);

	if (hu->tx_skb) {
		kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	}

	/* Flush any pending characters in the driver and discipline. */
	serdev_device_write_flush(hu->serdev);

	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
		hu->proto->flush(hu);

	return 0;
}

/* Initialize device */
static int hci_uart_open(struct hci_dev *hdev)
{
	BT_DBG("%s %p", hdev->name, hdev);

	/* Undo clearing this from hci_uart_close() */
	hdev->flush = hci_uart_flush;

	return 0;
}

/* Close device */
static int hci_uart_close(struct hci_dev *hdev)
{
	BT_DBG("hdev %p", hdev);

	hci_uart_flush(hdev);
	hdev->flush = NULL;

	return 0;
}

/* Send frames from HCI layer */
static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
{
	struct hci_uart *hu = hci_get_drvdata(hdev);

	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
	       skb->len);

	hu->proto->enqueue(hu, skb);

	hci_uart_tx_wakeup(hu);

	return 0;
}

static int hci_uart_setup(struct hci_dev *hdev)
{
	struct hci_uart *hu = hci_get_drvdata(hdev);
	struct hci_rp_read_local_version *ver;
	struct sk_buff *skb;
	unsigned int speed;
	int err;

	/* Init speed if any */
	if (hu->init_speed)
		speed = hu->init_speed;
	else if (hu->proto->init_speed)
		speed = hu->proto->init_speed;
	else
		speed = 0;

	if (speed)
		serdev_device_set_baudrate(hu->serdev, speed);

	/* Operational speed if any */
	if (hu->oper_speed)
		speed = hu->oper_speed;
	else if (hu->proto->oper_speed)
		speed = hu->proto->oper_speed;
	else
		speed = 0;

	if (hu->proto->set_baudrate && speed) {
		err = hu->proto->set_baudrate(hu, speed);
		if (err)
			bt_dev_err(hdev, "Failed to set baudrate");
		else
			serdev_device_set_baudrate(hu->serdev, speed);
	}

	if (hu->proto->setup)
		return hu->proto->setup(hu);

	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
		return 0;

	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
			     HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Reading local version info failed (%ld)",
			   PTR_ERR(skb));
		return 0;
	}

	if (skb->len != sizeof(*ver))
		bt_dev_err(hdev, "Event length mismatch for version info");

	kfree_skb(skb);
	return 0;
}

/** hci_uart_write_wakeup - transmit buffer wakeup
 * @serdev: serial device
 *
 * This function is called by the serdev framework when it accepts
 * more data being sent.
 */
static void hci_uart_write_wakeup(struct serdev_device *serdev)
{
	struct hci_uart *hu = serdev_device_get_drvdata(serdev);

	BT_DBG("");

	if (!hu || serdev != hu->serdev) {
		WARN_ON(1);
		return;
	}

	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
		hci_uart_tx_wakeup(hu);
}

/** hci_uart_receive_buf - receive buffer wakeup
 * @serdev: serial device
 * @data:   pointer to received data
 * @count:  count of received data in bytes
 *
 * This function is called by the serdev framework when it received data
 * in the RX buffer.
 *
 * Return: number of processed bytes
 */
static int hci_uart_receive_buf(struct serdev_device *serdev, const u8 *data,
				   size_t count)
{
	struct hci_uart *hu = serdev_device_get_drvdata(serdev);

	if (!hu || serdev != hu->serdev) {
		WARN_ON(1);
		return 0;
	}

	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
		return 0;

	/* It does not need a lock here as it is already protected by a mutex in
	 * tty caller
	 */
	hu->proto->recv(hu, data, count);

	if (hu->hdev)
		hu->hdev->stat.byte_rx += count;

	return count;
}

static struct serdev_device_ops hci_serdev_client_ops = {
	.receive_buf = hci_uart_receive_buf,
	.write_wakeup = hci_uart_write_wakeup,
};

int hci_uart_register_device(struct hci_uart *hu,
			     const struct hci_uart_proto *p)
{
	int err;
	struct hci_dev *hdev;

	BT_DBG("");

	serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops);

	err = serdev_device_open(hu->serdev);
	if (err)
		return err;

	err = p->open(hu);
	if (err)
		goto err_open;

	hu->proto = p;
	set_bit(HCI_UART_PROTO_READY, &hu->flags);

	/* Initialize and register HCI device */
	hdev = hci_alloc_dev();
	if (!hdev) {
		BT_ERR("Can't allocate HCI device");
		err = -ENOMEM;
		goto err_alloc;
	}

	hu->hdev = hdev;

	hdev->bus = HCI_UART;
	hci_set_drvdata(hdev, hu);

	INIT_WORK(&hu->init_ready, hci_uart_init_work);
	INIT_WORK(&hu->write_work, hci_uart_write_work);
	percpu_init_rwsem(&hu->proto_lock);

	/* Only when vendor specific setup callback is provided, consider
	 * the manufacturer information valid. This avoids filling in the
	 * value for Ericsson when nothing is specified.
	 */
	if (hu->proto->setup)
		hdev->manufacturer = hu->proto->manufacturer;

	hdev->open  = hci_uart_open;
	hdev->close = hci_uart_close;
	hdev->flush = hci_uart_flush;
	hdev->send  = hci_uart_send_frame;
	hdev->setup = hci_uart_setup;
	SET_HCIDEV_DEV(hdev, &hu->serdev->dev);

	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);

	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);

	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
		hdev->dev_type = HCI_AMP;
	else
		hdev->dev_type = HCI_PRIMARY;

	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
		return 0;

	if (hci_register_dev(hdev) < 0) {
		BT_ERR("Can't register HCI device");
		err = -ENODEV;
		goto err_register;
	}

	set_bit(HCI_UART_REGISTERED, &hu->flags);

	return 0;

err_register:
	hci_free_dev(hdev);
err_alloc:
	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
	p->close(hu);
err_open:
	serdev_device_close(hu->serdev);
	return err;
}
EXPORT_SYMBOL_GPL(hci_uart_register_device);

void hci_uart_unregister_device(struct hci_uart *hu)
{
	struct hci_dev *hdev = hu->hdev;

	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
	hci_unregister_dev(hdev);
	hci_free_dev(hdev);

	cancel_work_sync(&hu->write_work);

	hu->proto->close(hu);
	serdev_device_close(hu->serdev);
}
EXPORT_SYMBOL_GPL(hci_uart_unregister_device);
Commit	Line	Data
c942fddf	1	// SPDX-License-Identifier: GPL-2.0-or-later
82f5169b RH	2	/*
	3	* Bluetooth HCI serdev driver lib
	4	*
	5	* Copyright (C) 2017 Linaro, Ltd., Rob Herring <robh@kernel.org>
	6	*
	7	* Based on hci_ldisc.c:
	8	*
	9	* Copyright (C) 2000-2001 Qualcomm Incorporated
	10	* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
	11	* Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
82f5169b RH	12	*/
	13
	14	#include <linux/kernel.h>
	15	#include <linux/types.h>
	16	#include <linux/serdev.h>
	17	#include <linux/skbuff.h>
	18
	19	#include <net/bluetooth/bluetooth.h>
	20	#include <net/bluetooth/hci_core.h>
	21
	22	#include "hci_uart.h"
	23
640e32c9	24	static struct serdev_device_ops hci_serdev_client_ops;
82f5169b RH	25
	26	static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type)
	27	{
	28	struct hci_dev *hdev = hu->hdev;
	29
	30	/* Update HCI stat counters */
	31	switch (pkt_type) {
	32	case HCI_COMMAND_PKT:
	33	hdev->stat.cmd_tx++;
	34	break;
	35
	36	case HCI_ACLDATA_PKT:
	37	hdev->stat.acl_tx++;
	38	break;
	39
	40	case HCI_SCODATA_PKT:
	41	hdev->stat.sco_tx++;
	42	break;
	43	}
	44	}
	45
	46	static inline struct sk_buff hci_uart_dequeue(struct hci_uart hu)
	47	{
	48	struct sk_buff *skb = hu->tx_skb;
	49
5a637751 BG	50	if (!skb) {
	51	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
	52	skb = hu->proto->dequeue(hu);
	53	} else
82f5169b RH	54	hu->tx_skb = NULL;
	55
	56	return skb;
	57	}
	58
	59	static void hci_uart_write_work(struct work_struct *work)
	60	{
	61	struct hci_uart *hu = container_of(work, struct hci_uart, write_work);
	62	struct serdev_device *serdev = hu->serdev;
	63	struct hci_dev *hdev = hu->hdev;
	64	struct sk_buff *skb;
	65
	66	/* REVISIT:
	67	* should we cope with bad skbs or ->write() returning an error value?
	68	*/
	69	do {
	70	clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state);
	71
	72	while ((skb = hci_uart_dequeue(hu))) {
	73	int len;
	74
	75	len = serdev_device_write_buf(serdev,
	76	skb->data, skb->len);
	77	hdev->stat.byte_tx += len;
	78
	79	skb_pull(skb, len);
	80	if (skb->len) {
	81	hu->tx_skb = skb;
	82	break;
	83	}
	84
	85	hci_uart_tx_complete(hu, hci_skb_pkt_type(skb));
	86	kfree_skb(skb);
	87	}
ea9ed991	88	} while (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state));
82f5169b RH	89
	90	clear_bit(HCI_UART_SENDING, &hu->tx_state);
	91	}
	92
	93	/* ------- Interface to HCI layer ------ */
	94
82f5169b RH	95	/* Reset device */
	96	static int hci_uart_flush(struct hci_dev *hdev)
	97	{
	98	struct hci_uart *hu = hci_get_drvdata(hdev);
	99
	100	BT_DBG("hdev %p serdev %p", hdev, hu->serdev);
	101
	102	if (hu->tx_skb) {
	103	kfree_skb(hu->tx_skb); hu->tx_skb = NULL;
	104	}
	105
	106	/* Flush any pending characters in the driver and discipline. */
	107	serdev_device_write_flush(hu->serdev);
	108
	109	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
	110	hu->proto->flush(hu);
	111
	112	return 0;
	113	}
	114
412fe29f HG	115	/* Initialize device */
	116	static int hci_uart_open(struct hci_dev *hdev)
	117	{
	118	BT_DBG("%s %p", hdev->name, hdev);
	119
	120	/* Undo clearing this from hci_uart_close() */
	121	hdev->flush = hci_uart_flush;
	122
	123	return 0;
	124	}
	125
82f5169b RH	126	/* Close device */
	127	static int hci_uart_close(struct hci_dev *hdev)
	128	{
82f5169b RH	129	BT_DBG("hdev %p", hdev);
	130
	131	hci_uart_flush(hdev);
	132	hdev->flush = NULL;
	133
82f5169b RH	134	return 0;
	135	}
	136
	137	/* Send frames from HCI layer */
	138	static int hci_uart_send_frame(struct hci_dev hdev, struct sk_buff skb)
	139	{
	140	struct hci_uart *hu = hci_get_drvdata(hdev);
	141
	142	BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb),
	143	skb->len);
	144
	145	hu->proto->enqueue(hu, skb);
	146
	147	hci_uart_tx_wakeup(hu);
	148
	149	return 0;
	150	}
	151
	152	static int hci_uart_setup(struct hci_dev *hdev)
	153	{
	154	struct hci_uart *hu = hci_get_drvdata(hdev);
	155	struct hci_rp_read_local_version *ver;
	156	struct sk_buff *skb;
	157	unsigned int speed;
	158	int err;
	159
	160	/* Init speed if any */
	161	if (hu->init_speed)
	162	speed = hu->init_speed;
	163	else if (hu->proto->init_speed)
	164	speed = hu->proto->init_speed;
	165	else
	166	speed = 0;
	167
	168	if (speed)
	169	serdev_device_set_baudrate(hu->serdev, speed);
	170
	171	/* Operational speed if any */
	172	if (hu->oper_speed)
	173	speed = hu->oper_speed;
	174	else if (hu->proto->oper_speed)
	175	speed = hu->proto->oper_speed;
	176	else
	177	speed = 0;
	178
	179	if (hu->proto->set_baudrate && speed) {
	180	err = hu->proto->set_baudrate(hu, speed);
	181	if (err)
2064ee33	182	bt_dev_err(hdev, "Failed to set baudrate");
82f5169b RH	183	else
	184	serdev_device_set_baudrate(hu->serdev, speed);
	185	}
	186
	187	if (hu->proto->setup)
	188	return hu->proto->setup(hu);
	189
	190	if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags))
	191	return 0;
	192
	193	skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
	194	HCI_INIT_TIMEOUT);
	195	if (IS_ERR(skb)) {
2064ee33 MH	196	bt_dev_err(hdev, "Reading local version info failed (%ld)",
2064ee33 MH	197	PTR_ERR(skb));
82f5169b RH	198	return 0;
	199	}
	200
0c0c09ff	201	if (skb->len != sizeof(*ver))
2064ee33	202	bt_dev_err(hdev, "Event length mismatch for version info");
82f5169b RH	203
	204	kfree_skb(skb);
	205	return 0;
	206	}
	207
	208	/** hci_uart_write_wakeup - transmit buffer wakeup
	209	* @serdev: serial device
	210	*
	211	* This function is called by the serdev framework when it accepts
	212	* more data being sent.
	213	*/
	214	static void hci_uart_write_wakeup(struct serdev_device *serdev)
	215	{
	216	struct hci_uart *hu = serdev_device_get_drvdata(serdev);
	217
	218	BT_DBG("");
	219
	220	if (!hu \|\| serdev != hu->serdev) {
	221	WARN_ON(1);
	222	return;
	223	}
	224
	225	if (test_bit(HCI_UART_PROTO_READY, &hu->flags))
	226	hci_uart_tx_wakeup(hu);
	227	}
	228
	229	/** hci_uart_receive_buf - receive buffer wakeup
	230	* @serdev: serial device
	231	* @data: pointer to received data
	232	* @count: count of received data in bytes
	233	*
	234	* This function is called by the serdev framework when it received data
	235	* in the RX buffer.
	236	*
	237	* Return: number of processed bytes
	238	*/
	239	static int hci_uart_receive_buf(struct serdev_device serdev, const u8 data,
	240	size_t count)
	241	{
	242	struct hci_uart *hu = serdev_device_get_drvdata(serdev);
	243
	244	if (!hu \|\| serdev != hu->serdev) {
	245	WARN_ON(1);
	246	return 0;
	247	}
	248
	249	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
	250	return 0;
	251
	252	/* It does not need a lock here as it is already protected by a mutex in
	253	* tty caller
	254	*/
	255	hu->proto->recv(hu, data, count);
	256
	257	if (hu->hdev)
	258	hu->hdev->stat.byte_rx += count;
	259
	260	return count;
	261	}
	262
640e32c9	263	static struct serdev_device_ops hci_serdev_client_ops = {
82f5169b RH	264	.receive_buf = hci_uart_receive_buf,
	265	.write_wakeup = hci_uart_write_wakeup,
	266	};
	267
	268	int hci_uart_register_device(struct hci_uart *hu,
	269	const struct hci_uart_proto *p)
	270	{
	271	int err;
	272	struct hci_dev *hdev;
	273
	274	BT_DBG("");
	275
52b318e6 SR	276	serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops);
52b318e6 SR	277
e9ca0807	278	err = serdev_device_open(hu->serdev);
82f5169b RH	279	if (err)
	280	return err;
	281
e9ca0807 HG	282	err = p->open(hu);
	283	if (err)
	284	goto err_open;
	285
82f5169b RH	286	hu->proto = p;
	287	set_bit(HCI_UART_PROTO_READY, &hu->flags);
	288
	289	/* Initialize and register HCI device */
	290	hdev = hci_alloc_dev();
	291	if (!hdev) {
	292	BT_ERR("Can't allocate HCI device");
	293	err = -ENOMEM;
	294	goto err_alloc;
	295	}
	296
	297	hu->hdev = hdev;
	298
	299	hdev->bus = HCI_UART;
	300	hci_set_drvdata(hdev, hu);
	301
fdee6d8f	302	INIT_WORK(&hu->init_ready, hci_uart_init_work);
82f5169b	303	INIT_WORK(&hu->write_work, hci_uart_write_work);
d73e1728	304	percpu_init_rwsem(&hu->proto_lock);
82f5169b RH	305
	306	/* Only when vendor specific setup callback is provided, consider
	307	* the manufacturer information valid. This avoids filling in the
	308	* value for Ericsson when nothing is specified.
	309	*/
	310	if (hu->proto->setup)
	311	hdev->manufacturer = hu->proto->manufacturer;
	312
	313	hdev->open = hci_uart_open;
	314	hdev->close = hci_uart_close;
	315	hdev->flush = hci_uart_flush;
	316	hdev->send = hci_uart_send_frame;
	317	hdev->setup = hci_uart_setup;
	318	SET_HCIDEV_DEV(hdev, &hu->serdev->dev);
	319
	320	if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags))
	321	set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
	322
	323	if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags))
	324	set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
	325
82f5169b RH	326	if (test_bit(HCI_UART_CREATE_AMP, &hu->hdev_flags))
	327	hdev->dev_type = HCI_AMP;
	328	else
	329	hdev->dev_type = HCI_PRIMARY;
	330
	331	if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags))
	332	return 0;
	333
	334	if (hci_register_dev(hdev) < 0) {
	335	BT_ERR("Can't register HCI device");
	336	err = -ENODEV;
	337	goto err_register;
	338	}
	339
	340	set_bit(HCI_UART_REGISTERED, &hu->flags);
	341
	342	return 0;
	343
	344	err_register:
	345	hci_free_dev(hdev);
	346	err_alloc:
	347	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
	348	p->close(hu);
e9ca0807 HG	349	err_open:
e9ca0807 HG	350	serdev_device_close(hu->serdev);
82f5169b RH	351	return err;
82f5169b RH	352	}
081f36a8	353	EXPORT_SYMBOL_GPL(hci_uart_register_device);
c34dc3bf IM	354
	355	void hci_uart_unregister_device(struct hci_uart *hu)
	356	{
	357	struct hci_dev *hdev = hu->hdev;
	358
7cf7846d	359	clear_bit(HCI_UART_PROTO_READY, &hu->flags);
c34dc3bf IM	360	hci_unregister_dev(hdev);
	361	hci_free_dev(hdev);
	362
	363	cancel_work_sync(&hu->write_work);
	364
	365	hu->proto->close(hu);
e9ca0807	366	serdev_device_close(hu->serdev);
c34dc3bf IM	367	}
c34dc3bf IM	368	EXPORT_SYMBOL_GPL(hci_uart_unregister_device);