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v6.8
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *
   4 *  Bluetooth HCI Three-wire UART driver
   5 *
   6 *  Copyright (C) 2012  Intel Corporation
   7 */
   8
   9#include <linux/acpi.h>
  10#include <linux/errno.h>
  11#include <linux/gpio/consumer.h>
  12#include <linux/kernel.h>
  13#include <linux/mod_devicetable.h>
  14#include <linux/of.h>
  15#include <linux/pm_runtime.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 "btrtl.h"
  23#include "hci_uart.h"
  24
  25#define SUSPEND_TIMEOUT_MS	6000
  26
  27#define HCI_3WIRE_ACK_PKT	0
  28#define HCI_3WIRE_LINK_PKT	15
  29
  30/* Sliding window size */
  31#define H5_TX_WIN_MAX		4
  32
  33#define H5_ACK_TIMEOUT	msecs_to_jiffies(250)
  34#define H5_SYNC_TIMEOUT	msecs_to_jiffies(100)
  35
  36/*
  37 * Maximum Three-wire packet:
  38 *     4 byte header + max value for 12-bit length + 2 bytes for CRC
  39 */
  40#define H5_MAX_LEN (4 + 0xfff + 2)
  41
  42/* Convenience macros for reading Three-wire header values */
  43#define H5_HDR_SEQ(hdr)		((hdr)[0] & 0x07)
  44#define H5_HDR_ACK(hdr)		(((hdr)[0] >> 3) & 0x07)
  45#define H5_HDR_CRC(hdr)		(((hdr)[0] >> 6) & 0x01)
  46#define H5_HDR_RELIABLE(hdr)	(((hdr)[0] >> 7) & 0x01)
  47#define H5_HDR_PKT_TYPE(hdr)	((hdr)[1] & 0x0f)
  48#define H5_HDR_LEN(hdr)		((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4))
  49
  50#define SLIP_DELIMITER	0xc0
  51#define SLIP_ESC	0xdb
  52#define SLIP_ESC_DELIM	0xdc
  53#define SLIP_ESC_ESC	0xdd
  54
  55/* H5 state flags */
  56enum {
  57	H5_RX_ESC,		/* SLIP escape mode */
  58	H5_TX_ACK_REQ,		/* Pending ack to send */
  59	H5_WAKEUP_DISABLE,	/* Device cannot wake host */
  60	H5_HW_FLOW_CONTROL,	/* Use HW flow control */
  61};
  62
  63struct h5 {
  64	/* Must be the first member, hci_serdev.c expects this. */
  65	struct hci_uart		serdev_hu;
  66
  67	struct sk_buff_head	unack;		/* Unack'ed packets queue */
  68	struct sk_buff_head	rel;		/* Reliable packets queue */
  69	struct sk_buff_head	unrel;		/* Unreliable packets queue */
  70
  71	unsigned long		flags;
  72
  73	struct sk_buff		*rx_skb;	/* Receive buffer */
  74	size_t			rx_pending;	/* Expecting more bytes */
  75	u8			rx_ack;		/* Last ack number received */
  76
  77	int			(*rx_func)(struct hci_uart *hu, u8 c);
  78
  79	struct timer_list	timer;		/* Retransmission timer */
  80	struct hci_uart		*hu;		/* Parent HCI UART */
  81
  82	u8			tx_seq;		/* Next seq number to send */
  83	u8			tx_ack;		/* Next ack number to send */
  84	u8			tx_win;		/* Sliding window size */
  85
  86	enum {
  87		H5_UNINITIALIZED,
  88		H5_INITIALIZED,
  89		H5_ACTIVE,
  90	} state;
  91
  92	enum {
  93		H5_AWAKE,
  94		H5_SLEEPING,
  95		H5_WAKING_UP,
  96	} sleep;
  97
  98	const struct h5_vnd *vnd;
  99	const char *id;
 100
 101	struct gpio_desc *enable_gpio;
 102	struct gpio_desc *device_wake_gpio;
 103};
 104
 105enum h5_driver_info {
 106	H5_INFO_WAKEUP_DISABLE = BIT(0),
 107};
 108
 109struct h5_vnd {
 110	int (*setup)(struct h5 *h5);
 111	void (*open)(struct h5 *h5);
 112	void (*close)(struct h5 *h5);
 113	int (*suspend)(struct h5 *h5);
 114	int (*resume)(struct h5 *h5);
 115	const struct acpi_gpio_mapping *acpi_gpio_map;
 116};
 117
 118struct h5_device_data {
 119	uint32_t driver_info;
 120	struct h5_vnd *vnd;
 121};
 122
 123static void h5_reset_rx(struct h5 *h5);
 124
 125static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
 126{
 127	struct h5 *h5 = hu->priv;
 128	struct sk_buff *nskb;
 129
 130	nskb = alloc_skb(3, GFP_ATOMIC);
 131	if (!nskb)
 132		return;
 133
 134	hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
 135
 136	skb_put_data(nskb, data, len);
 137
 138	skb_queue_tail(&h5->unrel, nskb);
 139}
 140
 141static u8 h5_cfg_field(struct h5 *h5)
 142{
 143	/* Sliding window size (first 3 bits) */
 144	return h5->tx_win & 0x07;
 145}
 146
 147static void h5_timed_event(struct timer_list *t)
 148{
 149	const unsigned char sync_req[] = { 0x01, 0x7e };
 150	unsigned char conf_req[3] = { 0x03, 0xfc };
 151	struct h5 *h5 = from_timer(h5, t, timer);
 152	struct hci_uart *hu = h5->hu;
 153	struct sk_buff *skb;
 154	unsigned long flags;
 155
 156	BT_DBG("%s", hu->hdev->name);
 157
 158	if (h5->state == H5_UNINITIALIZED)
 159		h5_link_control(hu, sync_req, sizeof(sync_req));
 160
 161	if (h5->state == H5_INITIALIZED) {
 162		conf_req[2] = h5_cfg_field(h5);
 163		h5_link_control(hu, conf_req, sizeof(conf_req));
 164	}
 165
 166	if (h5->state != H5_ACTIVE) {
 167		mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 168		goto wakeup;
 169	}
 170
 171	if (h5->sleep != H5_AWAKE) {
 172		h5->sleep = H5_SLEEPING;
 173		goto wakeup;
 174	}
 175
 176	BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
 177
 178	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 179
 180	while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
 181		h5->tx_seq = (h5->tx_seq - 1) & 0x07;
 182		skb_queue_head(&h5->rel, skb);
 183	}
 184
 185	spin_unlock_irqrestore(&h5->unack.lock, flags);
 186
 187wakeup:
 188	hci_uart_tx_wakeup(hu);
 189}
 190
 191static void h5_peer_reset(struct hci_uart *hu)
 192{
 193	struct h5 *h5 = hu->priv;
 194
 195	bt_dev_err(hu->hdev, "Peer device has reset");
 196
 197	h5->state = H5_UNINITIALIZED;
 198
 199	del_timer(&h5->timer);
 200
 201	skb_queue_purge(&h5->rel);
 202	skb_queue_purge(&h5->unrel);
 203	skb_queue_purge(&h5->unack);
 204
 205	h5->tx_seq = 0;
 206	h5->tx_ack = 0;
 207
 208	/* Send reset request to upper stack */
 209	hci_reset_dev(hu->hdev);
 210}
 211
 212static int h5_open(struct hci_uart *hu)
 213{
 214	struct h5 *h5;
 215	const unsigned char sync[] = { 0x01, 0x7e };
 216
 217	BT_DBG("hu %p", hu);
 218
 219	if (hu->serdev) {
 220		h5 = serdev_device_get_drvdata(hu->serdev);
 221	} else {
 222		h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
 223		if (!h5)
 224			return -ENOMEM;
 225	}
 226
 227	hu->priv = h5;
 228	h5->hu = hu;
 229
 230	skb_queue_head_init(&h5->unack);
 231	skb_queue_head_init(&h5->rel);
 232	skb_queue_head_init(&h5->unrel);
 233
 234	h5_reset_rx(h5);
 235
 236	timer_setup(&h5->timer, h5_timed_event, 0);
 237
 238	h5->tx_win = H5_TX_WIN_MAX;
 239
 240	if (h5->vnd && h5->vnd->open)
 241		h5->vnd->open(h5);
 242
 243	set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
 244
 245	/* Send initial sync request */
 246	h5_link_control(hu, sync, sizeof(sync));
 247	mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 248
 249	return 0;
 250}
 251
 252static int h5_close(struct hci_uart *hu)
 253{
 254	struct h5 *h5 = hu->priv;
 255
 256	del_timer_sync(&h5->timer);
 257
 258	skb_queue_purge(&h5->unack);
 259	skb_queue_purge(&h5->rel);
 260	skb_queue_purge(&h5->unrel);
 261
 262	kfree_skb(h5->rx_skb);
 263	h5->rx_skb = NULL;
 264
 265	if (h5->vnd && h5->vnd->close)
 266		h5->vnd->close(h5);
 267
 268	if (!hu->serdev)
 269		kfree(h5);
 270
 271	return 0;
 272}
 273
 274static int h5_setup(struct hci_uart *hu)
 275{
 276	struct h5 *h5 = hu->priv;
 277
 278	if (h5->vnd && h5->vnd->setup)
 279		return h5->vnd->setup(h5);
 280
 281	return 0;
 282}
 283
 284static void h5_pkt_cull(struct h5 *h5)
 285{
 286	struct sk_buff *skb, *tmp;
 287	unsigned long flags;
 288	int i, to_remove;
 289	u8 seq;
 290
 291	spin_lock_irqsave(&h5->unack.lock, flags);
 292
 293	to_remove = skb_queue_len(&h5->unack);
 294	if (to_remove == 0)
 295		goto unlock;
 296
 297	seq = h5->tx_seq;
 298
 299	while (to_remove > 0) {
 300		if (h5->rx_ack == seq)
 301			break;
 302
 303		to_remove--;
 304		seq = (seq - 1) & 0x07;
 305	}
 306
 307	if (seq != h5->rx_ack)
 308		BT_ERR("Controller acked invalid packet");
 309
 310	i = 0;
 311	skb_queue_walk_safe(&h5->unack, skb, tmp) {
 312		if (i++ >= to_remove)
 313			break;
 314
 315		__skb_unlink(skb, &h5->unack);
 316		dev_kfree_skb_irq(skb);
 317	}
 318
 319	if (skb_queue_empty(&h5->unack))
 320		del_timer(&h5->timer);
 321
 322unlock:
 323	spin_unlock_irqrestore(&h5->unack.lock, flags);
 324}
 325
 326static void h5_handle_internal_rx(struct hci_uart *hu)
 327{
 328	struct h5 *h5 = hu->priv;
 329	const unsigned char sync_req[] = { 0x01, 0x7e };
 330	const unsigned char sync_rsp[] = { 0x02, 0x7d };
 331	unsigned char conf_req[3] = { 0x03, 0xfc };
 332	const unsigned char conf_rsp[] = { 0x04, 0x7b };
 333	const unsigned char wakeup_req[] = { 0x05, 0xfa };
 334	const unsigned char woken_req[] = { 0x06, 0xf9 };
 335	const unsigned char sleep_req[] = { 0x07, 0x78 };
 336	const unsigned char *hdr = h5->rx_skb->data;
 337	const unsigned char *data = &h5->rx_skb->data[4];
 338
 339	BT_DBG("%s", hu->hdev->name);
 340
 341	if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
 342		return;
 343
 344	if (H5_HDR_LEN(hdr) < 2)
 345		return;
 346
 347	conf_req[2] = h5_cfg_field(h5);
 348
 349	if (memcmp(data, sync_req, 2) == 0) {
 350		if (h5->state == H5_ACTIVE)
 351			h5_peer_reset(hu);
 352		h5_link_control(hu, sync_rsp, 2);
 353	} else if (memcmp(data, sync_rsp, 2) == 0) {
 354		if (h5->state == H5_ACTIVE)
 355			h5_peer_reset(hu);
 356		h5->state = H5_INITIALIZED;
 357		h5_link_control(hu, conf_req, 3);
 358	} else if (memcmp(data, conf_req, 2) == 0) {
 359		h5_link_control(hu, conf_rsp, 2);
 360		h5_link_control(hu, conf_req, 3);
 361	} else if (memcmp(data, conf_rsp, 2) == 0) {
 362		if (H5_HDR_LEN(hdr) > 2)
 363			h5->tx_win = (data[2] & 0x07);
 364		BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
 365		h5->state = H5_ACTIVE;
 366		hci_uart_init_ready(hu);
 367		return;
 368	} else if (memcmp(data, sleep_req, 2) == 0) {
 369		BT_DBG("Peer went to sleep");
 370		h5->sleep = H5_SLEEPING;
 371		return;
 372	} else if (memcmp(data, woken_req, 2) == 0) {
 373		BT_DBG("Peer woke up");
 374		h5->sleep = H5_AWAKE;
 375	} else if (memcmp(data, wakeup_req, 2) == 0) {
 376		BT_DBG("Peer requested wakeup");
 377		h5_link_control(hu, woken_req, 2);
 378		h5->sleep = H5_AWAKE;
 379	} else {
 380		BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
 381		return;
 382	}
 383
 384	hci_uart_tx_wakeup(hu);
 385}
 386
 387static void h5_complete_rx_pkt(struct hci_uart *hu)
 388{
 389	struct h5 *h5 = hu->priv;
 390	const unsigned char *hdr = h5->rx_skb->data;
 391
 392	if (H5_HDR_RELIABLE(hdr)) {
 393		h5->tx_ack = (h5->tx_ack + 1) % 8;
 394		set_bit(H5_TX_ACK_REQ, &h5->flags);
 395		hci_uart_tx_wakeup(hu);
 396	}
 397
 398	h5->rx_ack = H5_HDR_ACK(hdr);
 399
 400	h5_pkt_cull(h5);
 401
 402	switch (H5_HDR_PKT_TYPE(hdr)) {
 403	case HCI_EVENT_PKT:
 404	case HCI_ACLDATA_PKT:
 405	case HCI_SCODATA_PKT:
 406	case HCI_ISODATA_PKT:
 407		hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
 408
 409		/* Remove Three-wire header */
 410		skb_pull(h5->rx_skb, 4);
 411
 412		hci_recv_frame(hu->hdev, h5->rx_skb);
 413		h5->rx_skb = NULL;
 414
 415		break;
 416
 417	default:
 418		h5_handle_internal_rx(hu);
 419		break;
 420	}
 421
 422	h5_reset_rx(h5);
 423}
 424
 425static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
 426{
 427	h5_complete_rx_pkt(hu);
 428
 429	return 0;
 430}
 431
 432static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
 433{
 434	struct h5 *h5 = hu->priv;
 435	const unsigned char *hdr = h5->rx_skb->data;
 436
 437	if (H5_HDR_CRC(hdr)) {
 438		h5->rx_func = h5_rx_crc;
 439		h5->rx_pending = 2;
 440	} else {
 441		h5_complete_rx_pkt(hu);
 442	}
 443
 444	return 0;
 445}
 446
 447static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
 448{
 449	struct h5 *h5 = hu->priv;
 450	const unsigned char *hdr = h5->rx_skb->data;
 451
 452	BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
 453	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 454	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 455	       H5_HDR_LEN(hdr));
 456
 457	if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
 458		bt_dev_err(hu->hdev, "Invalid header checksum");
 459		h5_reset_rx(h5);
 460		return 0;
 461	}
 462
 463	if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
 464		bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)",
 465			   H5_HDR_SEQ(hdr), h5->tx_ack);
 466		set_bit(H5_TX_ACK_REQ, &h5->flags);
 467		hci_uart_tx_wakeup(hu);
 468		h5_reset_rx(h5);
 469		return 0;
 470	}
 471
 472	if (h5->state != H5_ACTIVE &&
 473	    H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
 474		bt_dev_err(hu->hdev, "Non-link packet received in non-active state");
 475		h5_reset_rx(h5);
 476		return 0;
 477	}
 478
 479	h5->rx_func = h5_rx_payload;
 480	h5->rx_pending = H5_HDR_LEN(hdr);
 481
 482	return 0;
 483}
 484
 485static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
 486{
 487	struct h5 *h5 = hu->priv;
 488
 489	if (c == SLIP_DELIMITER)
 490		return 1;
 491
 492	h5->rx_func = h5_rx_3wire_hdr;
 493	h5->rx_pending = 4;
 494
 495	h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
 496	if (!h5->rx_skb) {
 497		bt_dev_err(hu->hdev, "Can't allocate mem for new packet");
 498		h5_reset_rx(h5);
 499		return -ENOMEM;
 500	}
 501
 502	h5->rx_skb->dev = (void *)hu->hdev;
 503
 504	return 0;
 505}
 506
 507static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
 508{
 509	struct h5 *h5 = hu->priv;
 510
 511	if (c == SLIP_DELIMITER)
 512		h5->rx_func = h5_rx_pkt_start;
 513
 514	return 1;
 515}
 516
 517static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
 518{
 519	const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
 520	const u8 *byte = &c;
 521
 522	if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
 523		set_bit(H5_RX_ESC, &h5->flags);
 524		return;
 525	}
 526
 527	if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
 528		switch (c) {
 529		case SLIP_ESC_DELIM:
 530			byte = &delim;
 531			break;
 532		case SLIP_ESC_ESC:
 533			byte = &esc;
 534			break;
 535		default:
 536			BT_ERR("Invalid esc byte 0x%02hhx", c);
 537			h5_reset_rx(h5);
 538			return;
 539		}
 540	}
 541
 542	skb_put_data(h5->rx_skb, byte, 1);
 543	h5->rx_pending--;
 544
 545	BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
 546}
 547
 548static void h5_reset_rx(struct h5 *h5)
 549{
 550	if (h5->rx_skb) {
 551		kfree_skb(h5->rx_skb);
 552		h5->rx_skb = NULL;
 553	}
 554
 555	h5->rx_func = h5_rx_delimiter;
 556	h5->rx_pending = 0;
 557	clear_bit(H5_RX_ESC, &h5->flags);
 558}
 559
 560static int h5_recv(struct hci_uart *hu, const void *data, int count)
 561{
 562	struct h5 *h5 = hu->priv;
 563	const unsigned char *ptr = data;
 564
 565	BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
 566	       count);
 567
 568	while (count > 0) {
 569		int processed;
 570
 571		if (h5->rx_pending > 0) {
 572			if (*ptr == SLIP_DELIMITER) {
 573				bt_dev_err(hu->hdev, "Too short H5 packet");
 574				h5_reset_rx(h5);
 575				continue;
 576			}
 577
 578			h5_unslip_one_byte(h5, *ptr);
 579
 580			ptr++; count--;
 581			continue;
 582		}
 583
 584		processed = h5->rx_func(hu, *ptr);
 585		if (processed < 0)
 586			return processed;
 587
 588		ptr += processed;
 589		count -= processed;
 590	}
 591
 592	if (hu->serdev) {
 593		pm_runtime_get(&hu->serdev->dev);
 594		pm_runtime_mark_last_busy(&hu->serdev->dev);
 595		pm_runtime_put_autosuspend(&hu->serdev->dev);
 596	}
 597
 598	return 0;
 599}
 600
 601static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 602{
 603	struct h5 *h5 = hu->priv;
 604
 605	if (skb->len > 0xfff) {
 606		bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len);
 607		kfree_skb(skb);
 608		return 0;
 609	}
 610
 611	if (h5->state != H5_ACTIVE) {
 612		bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state");
 613		kfree_skb(skb);
 614		return 0;
 615	}
 616
 617	switch (hci_skb_pkt_type(skb)) {
 618	case HCI_ACLDATA_PKT:
 619	case HCI_COMMAND_PKT:
 620		skb_queue_tail(&h5->rel, skb);
 621		break;
 622
 623	case HCI_SCODATA_PKT:
 624	case HCI_ISODATA_PKT:
 625		skb_queue_tail(&h5->unrel, skb);
 626		break;
 627
 628	default:
 629		bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb));
 630		kfree_skb(skb);
 631		break;
 632	}
 633
 634	if (hu->serdev) {
 635		pm_runtime_get_sync(&hu->serdev->dev);
 636		pm_runtime_mark_last_busy(&hu->serdev->dev);
 637		pm_runtime_put_autosuspend(&hu->serdev->dev);
 638	}
 639
 640	return 0;
 641}
 642
 643static void h5_slip_delim(struct sk_buff *skb)
 644{
 645	const char delim = SLIP_DELIMITER;
 646
 647	skb_put_data(skb, &delim, 1);
 648}
 649
 650static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
 651{
 652	const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
 653	const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
 654
 655	switch (c) {
 656	case SLIP_DELIMITER:
 657		skb_put_data(skb, &esc_delim, 2);
 658		break;
 659	case SLIP_ESC:
 660		skb_put_data(skb, &esc_esc, 2);
 661		break;
 662	default:
 663		skb_put_data(skb, &c, 1);
 664	}
 665}
 666
 667static bool valid_packet_type(u8 type)
 668{
 669	switch (type) {
 670	case HCI_ACLDATA_PKT:
 671	case HCI_COMMAND_PKT:
 672	case HCI_SCODATA_PKT:
 673	case HCI_ISODATA_PKT:
 674	case HCI_3WIRE_LINK_PKT:
 675	case HCI_3WIRE_ACK_PKT:
 676		return true;
 677	default:
 678		return false;
 679	}
 680}
 681
 682static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
 683				      const u8 *data, size_t len)
 684{
 685	struct h5 *h5 = hu->priv;
 686	struct sk_buff *nskb;
 687	u8 hdr[4];
 688	int i;
 689
 690	if (!valid_packet_type(pkt_type)) {
 691		bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type);
 692		return NULL;
 693	}
 694
 695	/*
 696	 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
 697	 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
 698	 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
 699	 * delimiters at start and end).
 700	 */
 701	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
 702	if (!nskb)
 703		return NULL;
 704
 705	hci_skb_pkt_type(nskb) = pkt_type;
 706
 707	h5_slip_delim(nskb);
 708
 709	hdr[0] = h5->tx_ack << 3;
 710	clear_bit(H5_TX_ACK_REQ, &h5->flags);
 711
 712	/* Reliable packet? */
 713	if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
 714		hdr[0] |= 1 << 7;
 715		hdr[0] |= h5->tx_seq;
 716		h5->tx_seq = (h5->tx_seq + 1) % 8;
 717	}
 718
 719	hdr[1] = pkt_type | ((len & 0x0f) << 4);
 720	hdr[2] = len >> 4;
 721	hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
 722
 723	BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
 724	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 725	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 726	       H5_HDR_LEN(hdr));
 727
 728	for (i = 0; i < 4; i++)
 729		h5_slip_one_byte(nskb, hdr[i]);
 730
 731	for (i = 0; i < len; i++)
 732		h5_slip_one_byte(nskb, data[i]);
 733
 734	h5_slip_delim(nskb);
 735
 736	return nskb;
 737}
 738
 739static struct sk_buff *h5_dequeue(struct hci_uart *hu)
 740{
 741	struct h5 *h5 = hu->priv;
 742	unsigned long flags;
 743	struct sk_buff *skb, *nskb;
 744
 745	if (h5->sleep != H5_AWAKE) {
 746		const unsigned char wakeup_req[] = { 0x05, 0xfa };
 747
 748		if (h5->sleep == H5_WAKING_UP)
 749			return NULL;
 750
 751		h5->sleep = H5_WAKING_UP;
 752		BT_DBG("Sending wakeup request");
 753
 754		mod_timer(&h5->timer, jiffies + HZ / 100);
 755		return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
 756	}
 757
 758	skb = skb_dequeue(&h5->unrel);
 759	if (skb) {
 760		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 761				      skb->data, skb->len);
 762		if (nskb) {
 763			kfree_skb(skb);
 764			return nskb;
 765		}
 766
 767		skb_queue_head(&h5->unrel, skb);
 768		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 769	}
 770
 771	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 772
 773	if (h5->unack.qlen >= h5->tx_win)
 774		goto unlock;
 775
 776	skb = skb_dequeue(&h5->rel);
 777	if (skb) {
 778		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 779				      skb->data, skb->len);
 780		if (nskb) {
 781			__skb_queue_tail(&h5->unack, skb);
 782			mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
 783			spin_unlock_irqrestore(&h5->unack.lock, flags);
 784			return nskb;
 785		}
 786
 787		skb_queue_head(&h5->rel, skb);
 788		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 789	}
 790
 791unlock:
 792	spin_unlock_irqrestore(&h5->unack.lock, flags);
 793
 794	if (test_bit(H5_TX_ACK_REQ, &h5->flags))
 795		return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
 796
 797	return NULL;
 798}
 799
 800static int h5_flush(struct hci_uart *hu)
 801{
 802	BT_DBG("hu %p", hu);
 803	return 0;
 804}
 805
 806static const struct hci_uart_proto h5p = {
 807	.id		= HCI_UART_3WIRE,
 808	.name		= "Three-wire (H5)",
 809	.open		= h5_open,
 810	.close		= h5_close,
 811	.setup		= h5_setup,
 812	.recv		= h5_recv,
 813	.enqueue	= h5_enqueue,
 814	.dequeue	= h5_dequeue,
 815	.flush		= h5_flush,
 816};
 817
 818static int h5_serdev_probe(struct serdev_device *serdev)
 819{
 820	struct device *dev = &serdev->dev;
 821	struct h5 *h5;
 822	const struct h5_device_data *data;
 823
 824	h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
 825	if (!h5)
 826		return -ENOMEM;
 827
 828	h5->hu = &h5->serdev_hu;
 829	h5->serdev_hu.serdev = serdev;
 830	serdev_device_set_drvdata(serdev, h5);
 831
 832	if (has_acpi_companion(dev)) {
 833		const struct acpi_device_id *match;
 834
 835		match = acpi_match_device(dev->driver->acpi_match_table, dev);
 836		if (!match)
 837			return -ENODEV;
 838
 839		data = (const struct h5_device_data *)match->driver_data;
 840		h5->vnd = data->vnd;
 841		h5->id  = (char *)match->id;
 842
 843		if (h5->vnd->acpi_gpio_map)
 844			devm_acpi_dev_add_driver_gpios(dev,
 845						       h5->vnd->acpi_gpio_map);
 846	} else {
 
 
 847		data = of_device_get_match_data(dev);
 848		if (!data)
 849			return -ENODEV;
 850
 851		h5->vnd = data->vnd;
 852	}
 853
 854	if (data->driver_info & H5_INFO_WAKEUP_DISABLE)
 855		set_bit(H5_WAKEUP_DISABLE, &h5->flags);
 856
 857	h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
 858	if (IS_ERR(h5->enable_gpio))
 859		return PTR_ERR(h5->enable_gpio);
 860
 861	h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
 862						       GPIOD_OUT_LOW);
 863	if (IS_ERR(h5->device_wake_gpio))
 864		return PTR_ERR(h5->device_wake_gpio);
 865
 866	return hci_uart_register_device(&h5->serdev_hu, &h5p);
 867}
 868
 869static void h5_serdev_remove(struct serdev_device *serdev)
 870{
 871	struct h5 *h5 = serdev_device_get_drvdata(serdev);
 872
 873	hci_uart_unregister_device(&h5->serdev_hu);
 874}
 875
 876static int __maybe_unused h5_serdev_suspend(struct device *dev)
 877{
 878	struct h5 *h5 = dev_get_drvdata(dev);
 879	int ret = 0;
 880
 881	if (h5->vnd && h5->vnd->suspend)
 882		ret = h5->vnd->suspend(h5);
 883
 884	return ret;
 885}
 886
 887static int __maybe_unused h5_serdev_resume(struct device *dev)
 888{
 889	struct h5 *h5 = dev_get_drvdata(dev);
 890	int ret = 0;
 891
 892	if (h5->vnd && h5->vnd->resume)
 893		ret = h5->vnd->resume(h5);
 894
 895	return ret;
 896}
 897
 898#ifdef CONFIG_BT_HCIUART_RTL
 899static int h5_btrtl_setup(struct h5 *h5)
 900{
 901	struct btrtl_device_info *btrtl_dev;
 902	struct sk_buff *skb;
 903	__le32 baudrate_data;
 904	u32 device_baudrate;
 905	unsigned int controller_baudrate;
 906	bool flow_control;
 907	int err;
 908
 909	btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
 910	if (IS_ERR(btrtl_dev))
 911		return PTR_ERR(btrtl_dev);
 912
 913	err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
 914				      &controller_baudrate, &device_baudrate,
 915				      &flow_control);
 916	if (err)
 917		goto out_free;
 918
 919	baudrate_data = cpu_to_le32(device_baudrate);
 920	skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
 921			     &baudrate_data, HCI_INIT_TIMEOUT);
 922	if (IS_ERR(skb)) {
 923		rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
 924		err = PTR_ERR(skb);
 925		goto out_free;
 926	} else {
 927		kfree_skb(skb);
 928	}
 929	/* Give the device some time to set up the new baudrate. */
 930	usleep_range(10000, 20000);
 931
 932	serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
 933	serdev_device_set_flow_control(h5->hu->serdev, flow_control);
 934
 935	if (flow_control)
 936		set_bit(H5_HW_FLOW_CONTROL, &h5->flags);
 937
 938	err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
 939	/* Give the device some time before the hci-core sends it a reset */
 940	usleep_range(10000, 20000);
 941	if (err)
 942		goto out_free;
 943
 944	btrtl_set_quirks(h5->hu->hdev, btrtl_dev);
 945
 946out_free:
 947	btrtl_free(btrtl_dev);
 948
 949	return err;
 950}
 951
 952static void h5_btrtl_open(struct h5 *h5)
 953{
 954	/*
 955	 * Since h5_btrtl_resume() does a device_reprobe() the suspend handling
 956	 * done by the hci_suspend_notifier is not necessary; it actually causes
 957	 * delays and a bunch of errors to get logged, so disable it.
 958	 */
 959	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
 960		set_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &h5->hu->flags);
 961
 962	/* Devices always start with these fixed parameters */
 963	serdev_device_set_flow_control(h5->hu->serdev, false);
 964	serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
 965	serdev_device_set_baudrate(h5->hu->serdev, 115200);
 966
 967	if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
 968		pm_runtime_set_active(&h5->hu->serdev->dev);
 969		pm_runtime_use_autosuspend(&h5->hu->serdev->dev);
 970		pm_runtime_set_autosuspend_delay(&h5->hu->serdev->dev,
 971						 SUSPEND_TIMEOUT_MS);
 972		pm_runtime_enable(&h5->hu->serdev->dev);
 973	}
 974
 975	/* The controller needs reset to startup */
 976	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 977	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 978	msleep(100);
 979
 980	/* The controller needs up to 500ms to wakeup */
 981	gpiod_set_value_cansleep(h5->enable_gpio, 1);
 982	gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
 983	msleep(500);
 984}
 985
 986static void h5_btrtl_close(struct h5 *h5)
 987{
 988	if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags))
 989		pm_runtime_disable(&h5->hu->serdev->dev);
 990
 991	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 992	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 993}
 994
 995/* Suspend/resume support. On many devices the RTL BT device loses power during
 996 * suspend/resume, causing it to lose its firmware and all state. So we simply
 997 * turn it off on suspend and reprobe on resume. This mirrors how RTL devices
 998 * are handled in the USB driver, where the BTUSB_WAKEUP_DISABLE is used which
 999 * also causes a reprobe on resume.
1000 */
1001static int h5_btrtl_suspend(struct h5 *h5)
1002{
1003	serdev_device_set_flow_control(h5->hu->serdev, false);
1004	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
1005
1006	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
1007		gpiod_set_value_cansleep(h5->enable_gpio, 0);
1008
1009	return 0;
1010}
1011
1012struct h5_btrtl_reprobe {
1013	struct device *dev;
1014	struct work_struct work;
1015};
1016
1017static void h5_btrtl_reprobe_worker(struct work_struct *work)
1018{
1019	struct h5_btrtl_reprobe *reprobe =
1020		container_of(work, struct h5_btrtl_reprobe, work);
1021	int ret;
1022
1023	ret = device_reprobe(reprobe->dev);
1024	if (ret && ret != -EPROBE_DEFER)
1025		dev_err(reprobe->dev, "Reprobe error %d\n", ret);
1026
1027	put_device(reprobe->dev);
1028	kfree(reprobe);
1029	module_put(THIS_MODULE);
1030}
1031
1032static int h5_btrtl_resume(struct h5 *h5)
1033{
1034	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
1035		struct h5_btrtl_reprobe *reprobe;
1036
1037		reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
1038		if (!reprobe)
1039			return -ENOMEM;
1040
1041		__module_get(THIS_MODULE);
1042
1043		INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker);
1044		reprobe->dev = get_device(&h5->hu->serdev->dev);
1045		queue_work(system_long_wq, &reprobe->work);
1046	} else {
1047		gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
1048
1049		if (test_bit(H5_HW_FLOW_CONTROL, &h5->flags))
1050			serdev_device_set_flow_control(h5->hu->serdev, true);
1051	}
1052
 
 
 
1053	return 0;
1054}
1055
1056static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
1057static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
1058static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
1059static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
1060	{ "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
1061	{ "enable-gpios", &btrtl_enable_gpios, 1 },
1062	{ "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
1063	{},
1064};
1065
1066static struct h5_vnd rtl_vnd = {
1067	.setup		= h5_btrtl_setup,
1068	.open		= h5_btrtl_open,
1069	.close		= h5_btrtl_close,
1070	.suspend	= h5_btrtl_suspend,
1071	.resume		= h5_btrtl_resume,
1072	.acpi_gpio_map	= acpi_btrtl_gpios,
1073};
1074
1075static const struct h5_device_data h5_data_rtl8822cs = {
1076	.vnd = &rtl_vnd,
1077};
1078
1079static const struct h5_device_data h5_data_rtl8723bs = {
1080	.driver_info = H5_INFO_WAKEUP_DISABLE,
1081	.vnd = &rtl_vnd,
1082};
1083#endif
1084
1085#ifdef CONFIG_ACPI
1086static const struct acpi_device_id h5_acpi_match[] = {
1087#ifdef CONFIG_BT_HCIUART_RTL
1088	{ "OBDA0623", (kernel_ulong_t)&h5_data_rtl8723bs },
1089	{ "OBDA8723", (kernel_ulong_t)&h5_data_rtl8723bs },
1090#endif
1091	{ },
1092};
1093MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
1094#endif
1095
1096static const struct dev_pm_ops h5_serdev_pm_ops = {
1097	SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume)
1098	SET_RUNTIME_PM_OPS(h5_serdev_suspend, h5_serdev_resume, NULL)
1099};
1100
1101static const struct of_device_id rtl_bluetooth_of_match[] = {
1102#ifdef CONFIG_BT_HCIUART_RTL
1103	{ .compatible = "realtek,rtl8822cs-bt",
1104	  .data = (const void *)&h5_data_rtl8822cs },
1105	{ .compatible = "realtek,rtl8723bs-bt",
1106	  .data = (const void *)&h5_data_rtl8723bs },
1107	{ .compatible = "realtek,rtl8723cs-bt",
1108	  .data = (const void *)&h5_data_rtl8723bs },
1109	{ .compatible = "realtek,rtl8723ds-bt",
1110	  .data = (const void *)&h5_data_rtl8723bs },
1111#endif
1112	{ },
1113};
1114MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match);
1115
1116static struct serdev_device_driver h5_serdev_driver = {
1117	.probe = h5_serdev_probe,
1118	.remove = h5_serdev_remove,
1119	.driver = {
1120		.name = "hci_uart_h5",
1121		.acpi_match_table = ACPI_PTR(h5_acpi_match),
1122		.pm = &h5_serdev_pm_ops,
1123		.of_match_table = rtl_bluetooth_of_match,
1124	},
1125};
1126
1127int __init h5_init(void)
1128{
1129	serdev_device_driver_register(&h5_serdev_driver);
1130	return hci_uart_register_proto(&h5p);
1131}
1132
1133int __exit h5_deinit(void)
1134{
1135	serdev_device_driver_unregister(&h5_serdev_driver);
1136	return hci_uart_unregister_proto(&h5p);
1137}
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *
   4 *  Bluetooth HCI Three-wire UART driver
   5 *
   6 *  Copyright (C) 2012  Intel Corporation
   7 */
   8
   9#include <linux/acpi.h>
  10#include <linux/errno.h>
  11#include <linux/gpio/consumer.h>
  12#include <linux/kernel.h>
  13#include <linux/mod_devicetable.h>
  14#include <linux/of_device.h>
 
  15#include <linux/serdev.h>
  16#include <linux/skbuff.h>
  17
  18#include <net/bluetooth/bluetooth.h>
  19#include <net/bluetooth/hci_core.h>
  20
  21#include "btrtl.h"
  22#include "hci_uart.h"
  23
 
 
  24#define HCI_3WIRE_ACK_PKT	0
  25#define HCI_3WIRE_LINK_PKT	15
  26
  27/* Sliding window size */
  28#define H5_TX_WIN_MAX		4
  29
  30#define H5_ACK_TIMEOUT	msecs_to_jiffies(250)
  31#define H5_SYNC_TIMEOUT	msecs_to_jiffies(100)
  32
  33/*
  34 * Maximum Three-wire packet:
  35 *     4 byte header + max value for 12-bit length + 2 bytes for CRC
  36 */
  37#define H5_MAX_LEN (4 + 0xfff + 2)
  38
  39/* Convenience macros for reading Three-wire header values */
  40#define H5_HDR_SEQ(hdr)		((hdr)[0] & 0x07)
  41#define H5_HDR_ACK(hdr)		(((hdr)[0] >> 3) & 0x07)
  42#define H5_HDR_CRC(hdr)		(((hdr)[0] >> 6) & 0x01)
  43#define H5_HDR_RELIABLE(hdr)	(((hdr)[0] >> 7) & 0x01)
  44#define H5_HDR_PKT_TYPE(hdr)	((hdr)[1] & 0x0f)
  45#define H5_HDR_LEN(hdr)		((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4))
  46
  47#define SLIP_DELIMITER	0xc0
  48#define SLIP_ESC	0xdb
  49#define SLIP_ESC_DELIM	0xdc
  50#define SLIP_ESC_ESC	0xdd
  51
  52/* H5 state flags */
  53enum {
  54	H5_RX_ESC,	/* SLIP escape mode */
  55	H5_TX_ACK_REQ,	/* Pending ack to send */
 
 
  56};
  57
  58struct h5 {
  59	/* Must be the first member, hci_serdev.c expects this. */
  60	struct hci_uart		serdev_hu;
  61
  62	struct sk_buff_head	unack;		/* Unack'ed packets queue */
  63	struct sk_buff_head	rel;		/* Reliable packets queue */
  64	struct sk_buff_head	unrel;		/* Unreliable packets queue */
  65
  66	unsigned long		flags;
  67
  68	struct sk_buff		*rx_skb;	/* Receive buffer */
  69	size_t			rx_pending;	/* Expecting more bytes */
  70	u8			rx_ack;		/* Last ack number received */
  71
  72	int			(*rx_func)(struct hci_uart *hu, u8 c);
  73
  74	struct timer_list	timer;		/* Retransmission timer */
  75	struct hci_uart		*hu;		/* Parent HCI UART */
  76
  77	u8			tx_seq;		/* Next seq number to send */
  78	u8			tx_ack;		/* Next ack number to send */
  79	u8			tx_win;		/* Sliding window size */
  80
  81	enum {
  82		H5_UNINITIALIZED,
  83		H5_INITIALIZED,
  84		H5_ACTIVE,
  85	} state;
  86
  87	enum {
  88		H5_AWAKE,
  89		H5_SLEEPING,
  90		H5_WAKING_UP,
  91	} sleep;
  92
  93	const struct h5_vnd *vnd;
  94	const char *id;
  95
  96	struct gpio_desc *enable_gpio;
  97	struct gpio_desc *device_wake_gpio;
  98};
  99
 
 
 
 
 100struct h5_vnd {
 101	int (*setup)(struct h5 *h5);
 102	void (*open)(struct h5 *h5);
 103	void (*close)(struct h5 *h5);
 104	int (*suspend)(struct h5 *h5);
 105	int (*resume)(struct h5 *h5);
 106	const struct acpi_gpio_mapping *acpi_gpio_map;
 107};
 108
 
 
 
 
 
 109static void h5_reset_rx(struct h5 *h5);
 110
 111static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
 112{
 113	struct h5 *h5 = hu->priv;
 114	struct sk_buff *nskb;
 115
 116	nskb = alloc_skb(3, GFP_ATOMIC);
 117	if (!nskb)
 118		return;
 119
 120	hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
 121
 122	skb_put_data(nskb, data, len);
 123
 124	skb_queue_tail(&h5->unrel, nskb);
 125}
 126
 127static u8 h5_cfg_field(struct h5 *h5)
 128{
 129	/* Sliding window size (first 3 bits) */
 130	return h5->tx_win & 0x07;
 131}
 132
 133static void h5_timed_event(struct timer_list *t)
 134{
 135	const unsigned char sync_req[] = { 0x01, 0x7e };
 136	unsigned char conf_req[3] = { 0x03, 0xfc };
 137	struct h5 *h5 = from_timer(h5, t, timer);
 138	struct hci_uart *hu = h5->hu;
 139	struct sk_buff *skb;
 140	unsigned long flags;
 141
 142	BT_DBG("%s", hu->hdev->name);
 143
 144	if (h5->state == H5_UNINITIALIZED)
 145		h5_link_control(hu, sync_req, sizeof(sync_req));
 146
 147	if (h5->state == H5_INITIALIZED) {
 148		conf_req[2] = h5_cfg_field(h5);
 149		h5_link_control(hu, conf_req, sizeof(conf_req));
 150	}
 151
 152	if (h5->state != H5_ACTIVE) {
 153		mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 154		goto wakeup;
 155	}
 156
 157	if (h5->sleep != H5_AWAKE) {
 158		h5->sleep = H5_SLEEPING;
 159		goto wakeup;
 160	}
 161
 162	BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
 163
 164	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 165
 166	while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
 167		h5->tx_seq = (h5->tx_seq - 1) & 0x07;
 168		skb_queue_head(&h5->rel, skb);
 169	}
 170
 171	spin_unlock_irqrestore(&h5->unack.lock, flags);
 172
 173wakeup:
 174	hci_uart_tx_wakeup(hu);
 175}
 176
 177static void h5_peer_reset(struct hci_uart *hu)
 178{
 179	struct h5 *h5 = hu->priv;
 180
 181	bt_dev_err(hu->hdev, "Peer device has reset");
 182
 183	h5->state = H5_UNINITIALIZED;
 184
 185	del_timer(&h5->timer);
 186
 187	skb_queue_purge(&h5->rel);
 188	skb_queue_purge(&h5->unrel);
 189	skb_queue_purge(&h5->unack);
 190
 191	h5->tx_seq = 0;
 192	h5->tx_ack = 0;
 193
 194	/* Send reset request to upper stack */
 195	hci_reset_dev(hu->hdev);
 196}
 197
 198static int h5_open(struct hci_uart *hu)
 199{
 200	struct h5 *h5;
 201	const unsigned char sync[] = { 0x01, 0x7e };
 202
 203	BT_DBG("hu %p", hu);
 204
 205	if (hu->serdev) {
 206		h5 = serdev_device_get_drvdata(hu->serdev);
 207	} else {
 208		h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
 209		if (!h5)
 210			return -ENOMEM;
 211	}
 212
 213	hu->priv = h5;
 214	h5->hu = hu;
 215
 216	skb_queue_head_init(&h5->unack);
 217	skb_queue_head_init(&h5->rel);
 218	skb_queue_head_init(&h5->unrel);
 219
 220	h5_reset_rx(h5);
 221
 222	timer_setup(&h5->timer, h5_timed_event, 0);
 223
 224	h5->tx_win = H5_TX_WIN_MAX;
 225
 226	if (h5->vnd && h5->vnd->open)
 227		h5->vnd->open(h5);
 228
 229	set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
 230
 231	/* Send initial sync request */
 232	h5_link_control(hu, sync, sizeof(sync));
 233	mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 234
 235	return 0;
 236}
 237
 238static int h5_close(struct hci_uart *hu)
 239{
 240	struct h5 *h5 = hu->priv;
 241
 242	del_timer_sync(&h5->timer);
 243
 244	skb_queue_purge(&h5->unack);
 245	skb_queue_purge(&h5->rel);
 246	skb_queue_purge(&h5->unrel);
 247
 248	kfree_skb(h5->rx_skb);
 249	h5->rx_skb = NULL;
 250
 251	if (h5->vnd && h5->vnd->close)
 252		h5->vnd->close(h5);
 253
 254	if (!hu->serdev)
 255		kfree(h5);
 256
 257	return 0;
 258}
 259
 260static int h5_setup(struct hci_uart *hu)
 261{
 262	struct h5 *h5 = hu->priv;
 263
 264	if (h5->vnd && h5->vnd->setup)
 265		return h5->vnd->setup(h5);
 266
 267	return 0;
 268}
 269
 270static void h5_pkt_cull(struct h5 *h5)
 271{
 272	struct sk_buff *skb, *tmp;
 273	unsigned long flags;
 274	int i, to_remove;
 275	u8 seq;
 276
 277	spin_lock_irqsave(&h5->unack.lock, flags);
 278
 279	to_remove = skb_queue_len(&h5->unack);
 280	if (to_remove == 0)
 281		goto unlock;
 282
 283	seq = h5->tx_seq;
 284
 285	while (to_remove > 0) {
 286		if (h5->rx_ack == seq)
 287			break;
 288
 289		to_remove--;
 290		seq = (seq - 1) & 0x07;
 291	}
 292
 293	if (seq != h5->rx_ack)
 294		BT_ERR("Controller acked invalid packet");
 295
 296	i = 0;
 297	skb_queue_walk_safe(&h5->unack, skb, tmp) {
 298		if (i++ >= to_remove)
 299			break;
 300
 301		__skb_unlink(skb, &h5->unack);
 302		kfree_skb(skb);
 303	}
 304
 305	if (skb_queue_empty(&h5->unack))
 306		del_timer(&h5->timer);
 307
 308unlock:
 309	spin_unlock_irqrestore(&h5->unack.lock, flags);
 310}
 311
 312static void h5_handle_internal_rx(struct hci_uart *hu)
 313{
 314	struct h5 *h5 = hu->priv;
 315	const unsigned char sync_req[] = { 0x01, 0x7e };
 316	const unsigned char sync_rsp[] = { 0x02, 0x7d };
 317	unsigned char conf_req[3] = { 0x03, 0xfc };
 318	const unsigned char conf_rsp[] = { 0x04, 0x7b };
 319	const unsigned char wakeup_req[] = { 0x05, 0xfa };
 320	const unsigned char woken_req[] = { 0x06, 0xf9 };
 321	const unsigned char sleep_req[] = { 0x07, 0x78 };
 322	const unsigned char *hdr = h5->rx_skb->data;
 323	const unsigned char *data = &h5->rx_skb->data[4];
 324
 325	BT_DBG("%s", hu->hdev->name);
 326
 327	if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
 328		return;
 329
 330	if (H5_HDR_LEN(hdr) < 2)
 331		return;
 332
 333	conf_req[2] = h5_cfg_field(h5);
 334
 335	if (memcmp(data, sync_req, 2) == 0) {
 336		if (h5->state == H5_ACTIVE)
 337			h5_peer_reset(hu);
 338		h5_link_control(hu, sync_rsp, 2);
 339	} else if (memcmp(data, sync_rsp, 2) == 0) {
 340		if (h5->state == H5_ACTIVE)
 341			h5_peer_reset(hu);
 342		h5->state = H5_INITIALIZED;
 343		h5_link_control(hu, conf_req, 3);
 344	} else if (memcmp(data, conf_req, 2) == 0) {
 345		h5_link_control(hu, conf_rsp, 2);
 346		h5_link_control(hu, conf_req, 3);
 347	} else if (memcmp(data, conf_rsp, 2) == 0) {
 348		if (H5_HDR_LEN(hdr) > 2)
 349			h5->tx_win = (data[2] & 0x07);
 350		BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
 351		h5->state = H5_ACTIVE;
 352		hci_uart_init_ready(hu);
 353		return;
 354	} else if (memcmp(data, sleep_req, 2) == 0) {
 355		BT_DBG("Peer went to sleep");
 356		h5->sleep = H5_SLEEPING;
 357		return;
 358	} else if (memcmp(data, woken_req, 2) == 0) {
 359		BT_DBG("Peer woke up");
 360		h5->sleep = H5_AWAKE;
 361	} else if (memcmp(data, wakeup_req, 2) == 0) {
 362		BT_DBG("Peer requested wakeup");
 363		h5_link_control(hu, woken_req, 2);
 364		h5->sleep = H5_AWAKE;
 365	} else {
 366		BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
 367		return;
 368	}
 369
 370	hci_uart_tx_wakeup(hu);
 371}
 372
 373static void h5_complete_rx_pkt(struct hci_uart *hu)
 374{
 375	struct h5 *h5 = hu->priv;
 376	const unsigned char *hdr = h5->rx_skb->data;
 377
 378	if (H5_HDR_RELIABLE(hdr)) {
 379		h5->tx_ack = (h5->tx_ack + 1) % 8;
 380		set_bit(H5_TX_ACK_REQ, &h5->flags);
 381		hci_uart_tx_wakeup(hu);
 382	}
 383
 384	h5->rx_ack = H5_HDR_ACK(hdr);
 385
 386	h5_pkt_cull(h5);
 387
 388	switch (H5_HDR_PKT_TYPE(hdr)) {
 389	case HCI_EVENT_PKT:
 390	case HCI_ACLDATA_PKT:
 391	case HCI_SCODATA_PKT:
 392	case HCI_ISODATA_PKT:
 393		hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
 394
 395		/* Remove Three-wire header */
 396		skb_pull(h5->rx_skb, 4);
 397
 398		hci_recv_frame(hu->hdev, h5->rx_skb);
 399		h5->rx_skb = NULL;
 400
 401		break;
 402
 403	default:
 404		h5_handle_internal_rx(hu);
 405		break;
 406	}
 407
 408	h5_reset_rx(h5);
 409}
 410
 411static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
 412{
 413	h5_complete_rx_pkt(hu);
 414
 415	return 0;
 416}
 417
 418static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
 419{
 420	struct h5 *h5 = hu->priv;
 421	const unsigned char *hdr = h5->rx_skb->data;
 422
 423	if (H5_HDR_CRC(hdr)) {
 424		h5->rx_func = h5_rx_crc;
 425		h5->rx_pending = 2;
 426	} else {
 427		h5_complete_rx_pkt(hu);
 428	}
 429
 430	return 0;
 431}
 432
 433static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
 434{
 435	struct h5 *h5 = hu->priv;
 436	const unsigned char *hdr = h5->rx_skb->data;
 437
 438	BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
 439	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 440	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 441	       H5_HDR_LEN(hdr));
 442
 443	if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
 444		bt_dev_err(hu->hdev, "Invalid header checksum");
 445		h5_reset_rx(h5);
 446		return 0;
 447	}
 448
 449	if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
 450		bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)",
 451			   H5_HDR_SEQ(hdr), h5->tx_ack);
 
 
 452		h5_reset_rx(h5);
 453		return 0;
 454	}
 455
 456	if (h5->state != H5_ACTIVE &&
 457	    H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
 458		bt_dev_err(hu->hdev, "Non-link packet received in non-active state");
 459		h5_reset_rx(h5);
 460		return 0;
 461	}
 462
 463	h5->rx_func = h5_rx_payload;
 464	h5->rx_pending = H5_HDR_LEN(hdr);
 465
 466	return 0;
 467}
 468
 469static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
 470{
 471	struct h5 *h5 = hu->priv;
 472
 473	if (c == SLIP_DELIMITER)
 474		return 1;
 475
 476	h5->rx_func = h5_rx_3wire_hdr;
 477	h5->rx_pending = 4;
 478
 479	h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
 480	if (!h5->rx_skb) {
 481		bt_dev_err(hu->hdev, "Can't allocate mem for new packet");
 482		h5_reset_rx(h5);
 483		return -ENOMEM;
 484	}
 485
 486	h5->rx_skb->dev = (void *)hu->hdev;
 487
 488	return 0;
 489}
 490
 491static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
 492{
 493	struct h5 *h5 = hu->priv;
 494
 495	if (c == SLIP_DELIMITER)
 496		h5->rx_func = h5_rx_pkt_start;
 497
 498	return 1;
 499}
 500
 501static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
 502{
 503	const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
 504	const u8 *byte = &c;
 505
 506	if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
 507		set_bit(H5_RX_ESC, &h5->flags);
 508		return;
 509	}
 510
 511	if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
 512		switch (c) {
 513		case SLIP_ESC_DELIM:
 514			byte = &delim;
 515			break;
 516		case SLIP_ESC_ESC:
 517			byte = &esc;
 518			break;
 519		default:
 520			BT_ERR("Invalid esc byte 0x%02hhx", c);
 521			h5_reset_rx(h5);
 522			return;
 523		}
 524	}
 525
 526	skb_put_data(h5->rx_skb, byte, 1);
 527	h5->rx_pending--;
 528
 529	BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
 530}
 531
 532static void h5_reset_rx(struct h5 *h5)
 533{
 534	if (h5->rx_skb) {
 535		kfree_skb(h5->rx_skb);
 536		h5->rx_skb = NULL;
 537	}
 538
 539	h5->rx_func = h5_rx_delimiter;
 540	h5->rx_pending = 0;
 541	clear_bit(H5_RX_ESC, &h5->flags);
 542}
 543
 544static int h5_recv(struct hci_uart *hu, const void *data, int count)
 545{
 546	struct h5 *h5 = hu->priv;
 547	const unsigned char *ptr = data;
 548
 549	BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
 550	       count);
 551
 552	while (count > 0) {
 553		int processed;
 554
 555		if (h5->rx_pending > 0) {
 556			if (*ptr == SLIP_DELIMITER) {
 557				bt_dev_err(hu->hdev, "Too short H5 packet");
 558				h5_reset_rx(h5);
 559				continue;
 560			}
 561
 562			h5_unslip_one_byte(h5, *ptr);
 563
 564			ptr++; count--;
 565			continue;
 566		}
 567
 568		processed = h5->rx_func(hu, *ptr);
 569		if (processed < 0)
 570			return processed;
 571
 572		ptr += processed;
 573		count -= processed;
 574	}
 575
 
 
 
 
 
 
 576	return 0;
 577}
 578
 579static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 580{
 581	struct h5 *h5 = hu->priv;
 582
 583	if (skb->len > 0xfff) {
 584		bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len);
 585		kfree_skb(skb);
 586		return 0;
 587	}
 588
 589	if (h5->state != H5_ACTIVE) {
 590		bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state");
 591		kfree_skb(skb);
 592		return 0;
 593	}
 594
 595	switch (hci_skb_pkt_type(skb)) {
 596	case HCI_ACLDATA_PKT:
 597	case HCI_COMMAND_PKT:
 598		skb_queue_tail(&h5->rel, skb);
 599		break;
 600
 601	case HCI_SCODATA_PKT:
 602	case HCI_ISODATA_PKT:
 603		skb_queue_tail(&h5->unrel, skb);
 604		break;
 605
 606	default:
 607		bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb));
 608		kfree_skb(skb);
 609		break;
 610	}
 611
 
 
 
 
 
 
 612	return 0;
 613}
 614
 615static void h5_slip_delim(struct sk_buff *skb)
 616{
 617	const char delim = SLIP_DELIMITER;
 618
 619	skb_put_data(skb, &delim, 1);
 620}
 621
 622static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
 623{
 624	const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
 625	const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
 626
 627	switch (c) {
 628	case SLIP_DELIMITER:
 629		skb_put_data(skb, &esc_delim, 2);
 630		break;
 631	case SLIP_ESC:
 632		skb_put_data(skb, &esc_esc, 2);
 633		break;
 634	default:
 635		skb_put_data(skb, &c, 1);
 636	}
 637}
 638
 639static bool valid_packet_type(u8 type)
 640{
 641	switch (type) {
 642	case HCI_ACLDATA_PKT:
 643	case HCI_COMMAND_PKT:
 644	case HCI_SCODATA_PKT:
 645	case HCI_ISODATA_PKT:
 646	case HCI_3WIRE_LINK_PKT:
 647	case HCI_3WIRE_ACK_PKT:
 648		return true;
 649	default:
 650		return false;
 651	}
 652}
 653
 654static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
 655				      const u8 *data, size_t len)
 656{
 657	struct h5 *h5 = hu->priv;
 658	struct sk_buff *nskb;
 659	u8 hdr[4];
 660	int i;
 661
 662	if (!valid_packet_type(pkt_type)) {
 663		bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type);
 664		return NULL;
 665	}
 666
 667	/*
 668	 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
 669	 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
 670	 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
 671	 * delimiters at start and end).
 672	 */
 673	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
 674	if (!nskb)
 675		return NULL;
 676
 677	hci_skb_pkt_type(nskb) = pkt_type;
 678
 679	h5_slip_delim(nskb);
 680
 681	hdr[0] = h5->tx_ack << 3;
 682	clear_bit(H5_TX_ACK_REQ, &h5->flags);
 683
 684	/* Reliable packet? */
 685	if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
 686		hdr[0] |= 1 << 7;
 687		hdr[0] |= h5->tx_seq;
 688		h5->tx_seq = (h5->tx_seq + 1) % 8;
 689	}
 690
 691	hdr[1] = pkt_type | ((len & 0x0f) << 4);
 692	hdr[2] = len >> 4;
 693	hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
 694
 695	BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
 696	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 697	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 698	       H5_HDR_LEN(hdr));
 699
 700	for (i = 0; i < 4; i++)
 701		h5_slip_one_byte(nskb, hdr[i]);
 702
 703	for (i = 0; i < len; i++)
 704		h5_slip_one_byte(nskb, data[i]);
 705
 706	h5_slip_delim(nskb);
 707
 708	return nskb;
 709}
 710
 711static struct sk_buff *h5_dequeue(struct hci_uart *hu)
 712{
 713	struct h5 *h5 = hu->priv;
 714	unsigned long flags;
 715	struct sk_buff *skb, *nskb;
 716
 717	if (h5->sleep != H5_AWAKE) {
 718		const unsigned char wakeup_req[] = { 0x05, 0xfa };
 719
 720		if (h5->sleep == H5_WAKING_UP)
 721			return NULL;
 722
 723		h5->sleep = H5_WAKING_UP;
 724		BT_DBG("Sending wakeup request");
 725
 726		mod_timer(&h5->timer, jiffies + HZ / 100);
 727		return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
 728	}
 729
 730	skb = skb_dequeue(&h5->unrel);
 731	if (skb) {
 732		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 733				      skb->data, skb->len);
 734		if (nskb) {
 735			kfree_skb(skb);
 736			return nskb;
 737		}
 738
 739		skb_queue_head(&h5->unrel, skb);
 740		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 741	}
 742
 743	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 744
 745	if (h5->unack.qlen >= h5->tx_win)
 746		goto unlock;
 747
 748	skb = skb_dequeue(&h5->rel);
 749	if (skb) {
 750		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 751				      skb->data, skb->len);
 752		if (nskb) {
 753			__skb_queue_tail(&h5->unack, skb);
 754			mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
 755			spin_unlock_irqrestore(&h5->unack.lock, flags);
 756			return nskb;
 757		}
 758
 759		skb_queue_head(&h5->rel, skb);
 760		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 761	}
 762
 763unlock:
 764	spin_unlock_irqrestore(&h5->unack.lock, flags);
 765
 766	if (test_bit(H5_TX_ACK_REQ, &h5->flags))
 767		return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
 768
 769	return NULL;
 770}
 771
 772static int h5_flush(struct hci_uart *hu)
 773{
 774	BT_DBG("hu %p", hu);
 775	return 0;
 776}
 777
 778static const struct hci_uart_proto h5p = {
 779	.id		= HCI_UART_3WIRE,
 780	.name		= "Three-wire (H5)",
 781	.open		= h5_open,
 782	.close		= h5_close,
 783	.setup		= h5_setup,
 784	.recv		= h5_recv,
 785	.enqueue	= h5_enqueue,
 786	.dequeue	= h5_dequeue,
 787	.flush		= h5_flush,
 788};
 789
 790static int h5_serdev_probe(struct serdev_device *serdev)
 791{
 792	struct device *dev = &serdev->dev;
 793	struct h5 *h5;
 
 794
 795	h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
 796	if (!h5)
 797		return -ENOMEM;
 798
 799	h5->hu = &h5->serdev_hu;
 800	h5->serdev_hu.serdev = serdev;
 801	serdev_device_set_drvdata(serdev, h5);
 802
 803	if (has_acpi_companion(dev)) {
 804		const struct acpi_device_id *match;
 805
 806		match = acpi_match_device(dev->driver->acpi_match_table, dev);
 807		if (!match)
 808			return -ENODEV;
 809
 810		h5->vnd = (const struct h5_vnd *)match->driver_data;
 
 811		h5->id  = (char *)match->id;
 812
 813		if (h5->vnd->acpi_gpio_map)
 814			devm_acpi_dev_add_driver_gpios(dev,
 815						       h5->vnd->acpi_gpio_map);
 816	} else {
 817		const void *data;
 818
 819		data = of_device_get_match_data(dev);
 820		if (!data)
 821			return -ENODEV;
 822
 823		h5->vnd = (const struct h5_vnd *)data;
 824	}
 825
 
 
 826
 827	h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
 828	if (IS_ERR(h5->enable_gpio))
 829		return PTR_ERR(h5->enable_gpio);
 830
 831	h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
 832						       GPIOD_OUT_LOW);
 833	if (IS_ERR(h5->device_wake_gpio))
 834		return PTR_ERR(h5->device_wake_gpio);
 835
 836	return hci_uart_register_device(&h5->serdev_hu, &h5p);
 837}
 838
 839static void h5_serdev_remove(struct serdev_device *serdev)
 840{
 841	struct h5 *h5 = serdev_device_get_drvdata(serdev);
 842
 843	hci_uart_unregister_device(&h5->serdev_hu);
 844}
 845
 846static int __maybe_unused h5_serdev_suspend(struct device *dev)
 847{
 848	struct h5 *h5 = dev_get_drvdata(dev);
 849	int ret = 0;
 850
 851	if (h5->vnd && h5->vnd->suspend)
 852		ret = h5->vnd->suspend(h5);
 853
 854	return ret;
 855}
 856
 857static int __maybe_unused h5_serdev_resume(struct device *dev)
 858{
 859	struct h5 *h5 = dev_get_drvdata(dev);
 860	int ret = 0;
 861
 862	if (h5->vnd && h5->vnd->resume)
 863		ret = h5->vnd->resume(h5);
 864
 865	return ret;
 866}
 867
 868#ifdef CONFIG_BT_HCIUART_RTL
 869static int h5_btrtl_setup(struct h5 *h5)
 870{
 871	struct btrtl_device_info *btrtl_dev;
 872	struct sk_buff *skb;
 873	__le32 baudrate_data;
 874	u32 device_baudrate;
 875	unsigned int controller_baudrate;
 876	bool flow_control;
 877	int err;
 878
 879	btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
 880	if (IS_ERR(btrtl_dev))
 881		return PTR_ERR(btrtl_dev);
 882
 883	err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
 884				      &controller_baudrate, &device_baudrate,
 885				      &flow_control);
 886	if (err)
 887		goto out_free;
 888
 889	baudrate_data = cpu_to_le32(device_baudrate);
 890	skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
 891			     &baudrate_data, HCI_INIT_TIMEOUT);
 892	if (IS_ERR(skb)) {
 893		rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
 894		err = PTR_ERR(skb);
 895		goto out_free;
 896	} else {
 897		kfree_skb(skb);
 898	}
 899	/* Give the device some time to set up the new baudrate. */
 900	usleep_range(10000, 20000);
 901
 902	serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
 903	serdev_device_set_flow_control(h5->hu->serdev, flow_control);
 904
 
 
 
 905	err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
 906	/* Give the device some time before the hci-core sends it a reset */
 907	usleep_range(10000, 20000);
 
 
 908
 909	btrtl_set_quirks(h5->hu->hdev, btrtl_dev);
 910
 911out_free:
 912	btrtl_free(btrtl_dev);
 913
 914	return err;
 915}
 916
 917static void h5_btrtl_open(struct h5 *h5)
 918{
 
 
 
 
 
 
 
 
 919	/* Devices always start with these fixed parameters */
 920	serdev_device_set_flow_control(h5->hu->serdev, false);
 921	serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
 922	serdev_device_set_baudrate(h5->hu->serdev, 115200);
 923
 
 
 
 
 
 
 
 
 
 
 
 
 
 924	/* The controller needs up to 500ms to wakeup */
 925	gpiod_set_value_cansleep(h5->enable_gpio, 1);
 926	gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
 927	msleep(500);
 928}
 929
 930static void h5_btrtl_close(struct h5 *h5)
 931{
 
 
 
 932	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 933	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 934}
 935
 936/* Suspend/resume support. On many devices the RTL BT device loses power during
 937 * suspend/resume, causing it to lose its firmware and all state. So we simply
 938 * turn it off on suspend and reprobe on resume.  This mirrors how RTL devices
 939 * are handled in the USB driver, where the USB_QUIRK_RESET_RESUME is used which
 940 * also causes a reprobe on resume.
 941 */
 942static int h5_btrtl_suspend(struct h5 *h5)
 943{
 944	serdev_device_set_flow_control(h5->hu->serdev, false);
 945	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 946	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 
 
 
 947	return 0;
 948}
 949
 950struct h5_btrtl_reprobe {
 951	struct device *dev;
 952	struct work_struct work;
 953};
 954
 955static void h5_btrtl_reprobe_worker(struct work_struct *work)
 956{
 957	struct h5_btrtl_reprobe *reprobe =
 958		container_of(work, struct h5_btrtl_reprobe, work);
 959	int ret;
 960
 961	ret = device_reprobe(reprobe->dev);
 962	if (ret && ret != -EPROBE_DEFER)
 963		dev_err(reprobe->dev, "Reprobe error %d\n", ret);
 964
 965	put_device(reprobe->dev);
 966	kfree(reprobe);
 967	module_put(THIS_MODULE);
 968}
 969
 970static int h5_btrtl_resume(struct h5 *h5)
 971{
 972	struct h5_btrtl_reprobe *reprobe;
 
 973
 974	reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
 975	if (!reprobe)
 976		return -ENOMEM;
 
 
 
 
 
 
 
 
 977
 978	__module_get(THIS_MODULE);
 
 
 979
 980	INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker);
 981	reprobe->dev = get_device(&h5->hu->serdev->dev);
 982	queue_work(system_long_wq, &reprobe->work);
 983	return 0;
 984}
 985
 986static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
 987static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
 988static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
 989static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
 990	{ "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
 991	{ "enable-gpios", &btrtl_enable_gpios, 1 },
 992	{ "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
 993	{},
 994};
 995
 996static struct h5_vnd rtl_vnd = {
 997	.setup		= h5_btrtl_setup,
 998	.open		= h5_btrtl_open,
 999	.close		= h5_btrtl_close,
1000	.suspend	= h5_btrtl_suspend,
1001	.resume		= h5_btrtl_resume,
1002	.acpi_gpio_map	= acpi_btrtl_gpios,
1003};
 
 
 
 
 
 
 
 
 
1004#endif
1005
1006#ifdef CONFIG_ACPI
1007static const struct acpi_device_id h5_acpi_match[] = {
1008#ifdef CONFIG_BT_HCIUART_RTL
1009	{ "OBDA0623", (kernel_ulong_t)&rtl_vnd },
1010	{ "OBDA8723", (kernel_ulong_t)&rtl_vnd },
1011#endif
1012	{ },
1013};
1014MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
1015#endif
1016
1017static const struct dev_pm_ops h5_serdev_pm_ops = {
1018	SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume)
 
1019};
1020
1021static const struct of_device_id rtl_bluetooth_of_match[] = {
1022#ifdef CONFIG_BT_HCIUART_RTL
1023	{ .compatible = "realtek,rtl8822cs-bt",
1024	  .data = (const void *)&rtl_vnd },
1025	{ .compatible = "realtek,rtl8723bs-bt",
1026	  .data = (const void *)&rtl_vnd },
 
 
1027	{ .compatible = "realtek,rtl8723ds-bt",
1028	  .data = (const void *)&rtl_vnd },
1029#endif
1030	{ },
1031};
1032MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match);
1033
1034static struct serdev_device_driver h5_serdev_driver = {
1035	.probe = h5_serdev_probe,
1036	.remove = h5_serdev_remove,
1037	.driver = {
1038		.name = "hci_uart_h5",
1039		.acpi_match_table = ACPI_PTR(h5_acpi_match),
1040		.pm = &h5_serdev_pm_ops,
1041		.of_match_table = rtl_bluetooth_of_match,
1042	},
1043};
1044
1045int __init h5_init(void)
1046{
1047	serdev_device_driver_register(&h5_serdev_driver);
1048	return hci_uart_register_proto(&h5p);
1049}
1050
1051int __exit h5_deinit(void)
1052{
1053	serdev_device_driver_unregister(&h5_serdev_driver);
1054	return hci_uart_unregister_proto(&h5p);
1055}