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v6.13.7
   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	int sizeof_priv;
 117};
 118
 119struct h5_device_data {
 120	uint32_t driver_info;
 121	struct h5_vnd *vnd;
 122};
 123
 124static void h5_reset_rx(struct h5 *h5);
 125
 126static void h5_link_control(struct hci_uart *hu, const void *data, size_t len)
 127{
 128	struct h5 *h5 = hu->priv;
 129	struct sk_buff *nskb;
 130
 131	nskb = alloc_skb(3, GFP_ATOMIC);
 132	if (!nskb)
 133		return;
 134
 135	hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT;
 136
 137	skb_put_data(nskb, data, len);
 138
 139	skb_queue_tail(&h5->unrel, nskb);
 140}
 141
 142static u8 h5_cfg_field(struct h5 *h5)
 143{
 144	/* Sliding window size (first 3 bits) */
 145	return h5->tx_win & 0x07;
 146}
 147
 148static void h5_timed_event(struct timer_list *t)
 149{
 150	const unsigned char sync_req[] = { 0x01, 0x7e };
 151	unsigned char conf_req[3] = { 0x03, 0xfc };
 152	struct h5 *h5 = from_timer(h5, t, timer);
 153	struct hci_uart *hu = h5->hu;
 154	struct sk_buff *skb;
 155	unsigned long flags;
 156
 157	BT_DBG("%s", hu->hdev->name);
 158
 159	if (h5->state == H5_UNINITIALIZED)
 160		h5_link_control(hu, sync_req, sizeof(sync_req));
 161
 162	if (h5->state == H5_INITIALIZED) {
 163		conf_req[2] = h5_cfg_field(h5);
 164		h5_link_control(hu, conf_req, sizeof(conf_req));
 165	}
 166
 167	if (h5->state != H5_ACTIVE) {
 168		mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 169		goto wakeup;
 170	}
 171
 172	if (h5->sleep != H5_AWAKE) {
 173		h5->sleep = H5_SLEEPING;
 174		goto wakeup;
 175	}
 176
 177	BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen);
 178
 179	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 180
 181	while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) {
 182		h5->tx_seq = (h5->tx_seq - 1) & 0x07;
 183		skb_queue_head(&h5->rel, skb);
 184	}
 185
 186	spin_unlock_irqrestore(&h5->unack.lock, flags);
 187
 188wakeup:
 189	hci_uart_tx_wakeup(hu);
 190}
 191
 192static void h5_peer_reset(struct hci_uart *hu)
 193{
 194	struct h5 *h5 = hu->priv;
 195
 196	bt_dev_err(hu->hdev, "Peer device has reset");
 197
 198	h5->state = H5_UNINITIALIZED;
 199
 200	del_timer(&h5->timer);
 201
 202	skb_queue_purge(&h5->rel);
 203	skb_queue_purge(&h5->unrel);
 204	skb_queue_purge(&h5->unack);
 205
 206	h5->tx_seq = 0;
 207	h5->tx_ack = 0;
 208
 209	/* Send reset request to upper stack */
 210	hci_reset_dev(hu->hdev);
 211}
 212
 213static int h5_open(struct hci_uart *hu)
 214{
 215	struct h5 *h5;
 216	const unsigned char sync[] = { 0x01, 0x7e };
 217
 218	BT_DBG("hu %p", hu);
 219
 220	if (hu->serdev) {
 221		h5 = serdev_device_get_drvdata(hu->serdev);
 222	} else {
 223		h5 = kzalloc(sizeof(*h5), GFP_KERNEL);
 224		if (!h5)
 225			return -ENOMEM;
 226	}
 227
 228	hu->priv = h5;
 229	h5->hu = hu;
 230
 231	skb_queue_head_init(&h5->unack);
 232	skb_queue_head_init(&h5->rel);
 233	skb_queue_head_init(&h5->unrel);
 234
 235	h5_reset_rx(h5);
 236
 237	timer_setup(&h5->timer, h5_timed_event, 0);
 238
 239	h5->tx_win = H5_TX_WIN_MAX;
 240
 241	if (h5->vnd && h5->vnd->open)
 242		h5->vnd->open(h5);
 243
 244	set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags);
 245
 246	/* Send initial sync request */
 247	h5_link_control(hu, sync, sizeof(sync));
 248	mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT);
 249
 250	return 0;
 251}
 252
 253static int h5_close(struct hci_uart *hu)
 254{
 255	struct h5 *h5 = hu->priv;
 256
 257	del_timer_sync(&h5->timer);
 258
 259	skb_queue_purge(&h5->unack);
 260	skb_queue_purge(&h5->rel);
 261	skb_queue_purge(&h5->unrel);
 262
 263	kfree_skb(h5->rx_skb);
 264	h5->rx_skb = NULL;
 265
 266	if (h5->vnd && h5->vnd->close)
 267		h5->vnd->close(h5);
 268
 269	if (!hu->serdev)
 270		kfree(h5);
 271
 272	return 0;
 273}
 274
 275static int h5_setup(struct hci_uart *hu)
 276{
 277	struct h5 *h5 = hu->priv;
 278
 279	if (h5->vnd && h5->vnd->setup)
 280		return h5->vnd->setup(h5);
 281
 282	return 0;
 283}
 284
 285static void h5_pkt_cull(struct h5 *h5)
 286{
 287	struct sk_buff *skb, *tmp;
 288	unsigned long flags;
 289	int i, to_remove;
 290	u8 seq;
 291
 292	spin_lock_irqsave(&h5->unack.lock, flags);
 293
 294	to_remove = skb_queue_len(&h5->unack);
 295	if (to_remove == 0)
 296		goto unlock;
 297
 298	seq = h5->tx_seq;
 299
 300	while (to_remove > 0) {
 301		if (h5->rx_ack == seq)
 302			break;
 303
 304		to_remove--;
 305		seq = (seq - 1) & 0x07;
 306	}
 307
 308	if (seq != h5->rx_ack)
 309		BT_ERR("Controller acked invalid packet");
 310
 311	i = 0;
 312	skb_queue_walk_safe(&h5->unack, skb, tmp) {
 313		if (i++ >= to_remove)
 314			break;
 315
 316		__skb_unlink(skb, &h5->unack);
 317		dev_kfree_skb_irq(skb);
 318	}
 319
 320	if (skb_queue_empty(&h5->unack))
 321		del_timer(&h5->timer);
 322
 323unlock:
 324	spin_unlock_irqrestore(&h5->unack.lock, flags);
 325}
 326
 327static void h5_handle_internal_rx(struct hci_uart *hu)
 328{
 329	struct h5 *h5 = hu->priv;
 330	const unsigned char sync_req[] = { 0x01, 0x7e };
 331	const unsigned char sync_rsp[] = { 0x02, 0x7d };
 332	unsigned char conf_req[3] = { 0x03, 0xfc };
 333	const unsigned char conf_rsp[] = { 0x04, 0x7b };
 334	const unsigned char wakeup_req[] = { 0x05, 0xfa };
 335	const unsigned char woken_req[] = { 0x06, 0xf9 };
 336	const unsigned char sleep_req[] = { 0x07, 0x78 };
 337	const unsigned char *hdr = h5->rx_skb->data;
 338	const unsigned char *data = &h5->rx_skb->data[4];
 339
 340	BT_DBG("%s", hu->hdev->name);
 341
 342	if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
 343		return;
 344
 345	if (H5_HDR_LEN(hdr) < 2)
 346		return;
 347
 348	conf_req[2] = h5_cfg_field(h5);
 349
 350	if (memcmp(data, sync_req, 2) == 0) {
 351		if (h5->state == H5_ACTIVE)
 352			h5_peer_reset(hu);
 353		h5_link_control(hu, sync_rsp, 2);
 354	} else if (memcmp(data, sync_rsp, 2) == 0) {
 355		if (h5->state == H5_ACTIVE)
 356			h5_peer_reset(hu);
 357		h5->state = H5_INITIALIZED;
 358		h5_link_control(hu, conf_req, 3);
 359	} else if (memcmp(data, conf_req, 2) == 0) {
 360		h5_link_control(hu, conf_rsp, 2);
 361		h5_link_control(hu, conf_req, 3);
 362	} else if (memcmp(data, conf_rsp, 2) == 0) {
 363		if (H5_HDR_LEN(hdr) > 2)
 364			h5->tx_win = (data[2] & 0x07);
 365		BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
 366		h5->state = H5_ACTIVE;
 367		hci_uart_init_ready(hu);
 368		return;
 369	} else if (memcmp(data, sleep_req, 2) == 0) {
 370		BT_DBG("Peer went to sleep");
 371		h5->sleep = H5_SLEEPING;
 372		return;
 373	} else if (memcmp(data, woken_req, 2) == 0) {
 374		BT_DBG("Peer woke up");
 375		h5->sleep = H5_AWAKE;
 376	} else if (memcmp(data, wakeup_req, 2) == 0) {
 377		BT_DBG("Peer requested wakeup");
 378		h5_link_control(hu, woken_req, 2);
 379		h5->sleep = H5_AWAKE;
 380	} else {
 381		BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
 382		return;
 383	}
 384
 385	hci_uart_tx_wakeup(hu);
 386}
 387
 388static void h5_complete_rx_pkt(struct hci_uart *hu)
 389{
 390	struct h5 *h5 = hu->priv;
 391	const unsigned char *hdr = h5->rx_skb->data;
 392
 393	if (H5_HDR_RELIABLE(hdr)) {
 394		h5->tx_ack = (h5->tx_ack + 1) % 8;
 395		set_bit(H5_TX_ACK_REQ, &h5->flags);
 396		hci_uart_tx_wakeup(hu);
 397	}
 398
 399	h5->rx_ack = H5_HDR_ACK(hdr);
 400
 401	h5_pkt_cull(h5);
 402
 403	switch (H5_HDR_PKT_TYPE(hdr)) {
 404	case HCI_EVENT_PKT:
 405	case HCI_ACLDATA_PKT:
 406	case HCI_SCODATA_PKT:
 407	case HCI_ISODATA_PKT:
 408		hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
 409
 410		/* Remove Three-wire header */
 411		skb_pull(h5->rx_skb, 4);
 412
 413		hci_recv_frame(hu->hdev, h5->rx_skb);
 414		h5->rx_skb = NULL;
 415
 416		break;
 417
 418	default:
 419		h5_handle_internal_rx(hu);
 420		break;
 421	}
 422
 423	h5_reset_rx(h5);
 424}
 425
 426static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
 427{
 428	h5_complete_rx_pkt(hu);
 429
 430	return 0;
 431}
 432
 433static int h5_rx_payload(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	if (H5_HDR_CRC(hdr)) {
 439		h5->rx_func = h5_rx_crc;
 440		h5->rx_pending = 2;
 441	} else {
 442		h5_complete_rx_pkt(hu);
 443	}
 444
 445	return 0;
 446}
 447
 448static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
 449{
 450	struct h5 *h5 = hu->priv;
 451	const unsigned char *hdr = h5->rx_skb->data;
 452
 453	BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
 454	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 455	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 456	       H5_HDR_LEN(hdr));
 457
 458	if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
 459		bt_dev_err(hu->hdev, "Invalid header checksum");
 460		h5_reset_rx(h5);
 461		return 0;
 462	}
 463
 464	if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
 465		bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)",
 466			   H5_HDR_SEQ(hdr), h5->tx_ack);
 467		set_bit(H5_TX_ACK_REQ, &h5->flags);
 468		hci_uart_tx_wakeup(hu);
 469		h5_reset_rx(h5);
 470		return 0;
 471	}
 472
 473	if (h5->state != H5_ACTIVE &&
 474	    H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
 475		bt_dev_err(hu->hdev, "Non-link packet received in non-active state");
 476		h5_reset_rx(h5);
 477		return 0;
 478	}
 479
 480	h5->rx_func = h5_rx_payload;
 481	h5->rx_pending = H5_HDR_LEN(hdr);
 482
 483	return 0;
 484}
 485
 486static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
 487{
 488	struct h5 *h5 = hu->priv;
 489
 490	if (c == SLIP_DELIMITER)
 491		return 1;
 492
 493	h5->rx_func = h5_rx_3wire_hdr;
 494	h5->rx_pending = 4;
 495
 496	h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
 497	if (!h5->rx_skb) {
 498		bt_dev_err(hu->hdev, "Can't allocate mem for new packet");
 499		h5_reset_rx(h5);
 500		return -ENOMEM;
 501	}
 502
 503	h5->rx_skb->dev = (void *)hu->hdev;
 504
 505	return 0;
 506}
 507
 508static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
 509{
 510	struct h5 *h5 = hu->priv;
 511
 512	if (c == SLIP_DELIMITER)
 513		h5->rx_func = h5_rx_pkt_start;
 514
 515	return 1;
 516}
 517
 518static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
 519{
 520	const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
 521	const u8 *byte = &c;
 522
 523	if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
 524		set_bit(H5_RX_ESC, &h5->flags);
 525		return;
 526	}
 527
 528	if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
 529		switch (c) {
 530		case SLIP_ESC_DELIM:
 531			byte = &delim;
 532			break;
 533		case SLIP_ESC_ESC:
 534			byte = &esc;
 535			break;
 536		default:
 537			BT_ERR("Invalid esc byte 0x%02hhx", c);
 538			h5_reset_rx(h5);
 539			return;
 540		}
 541	}
 542
 543	skb_put_data(h5->rx_skb, byte, 1);
 544	h5->rx_pending--;
 545
 546	BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
 547}
 548
 549static void h5_reset_rx(struct h5 *h5)
 550{
 551	if (h5->rx_skb) {
 552		kfree_skb(h5->rx_skb);
 553		h5->rx_skb = NULL;
 554	}
 555
 556	h5->rx_func = h5_rx_delimiter;
 557	h5->rx_pending = 0;
 558	clear_bit(H5_RX_ESC, &h5->flags);
 559}
 560
 561static int h5_recv(struct hci_uart *hu, const void *data, int count)
 562{
 563	struct h5 *h5 = hu->priv;
 564	const unsigned char *ptr = data;
 565
 566	BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
 567	       count);
 568
 569	while (count > 0) {
 570		int processed;
 571
 572		if (h5->rx_pending > 0) {
 573			if (*ptr == SLIP_DELIMITER) {
 574				bt_dev_err(hu->hdev, "Too short H5 packet");
 575				h5_reset_rx(h5);
 576				continue;
 577			}
 578
 579			h5_unslip_one_byte(h5, *ptr);
 580
 581			ptr++; count--;
 582			continue;
 583		}
 584
 585		processed = h5->rx_func(hu, *ptr);
 586		if (processed < 0)
 587			return processed;
 588
 589		ptr += processed;
 590		count -= processed;
 591	}
 592
 593	if (hu->serdev) {
 594		pm_runtime_get(&hu->serdev->dev);
 595		pm_runtime_mark_last_busy(&hu->serdev->dev);
 596		pm_runtime_put_autosuspend(&hu->serdev->dev);
 597	}
 598
 599	return 0;
 600}
 601
 602static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 603{
 604	struct h5 *h5 = hu->priv;
 605
 606	if (skb->len > 0xfff) {
 607		bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len);
 608		kfree_skb(skb);
 609		return 0;
 610	}
 611
 612	if (h5->state != H5_ACTIVE) {
 613		bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state");
 614		kfree_skb(skb);
 615		return 0;
 616	}
 617
 618	switch (hci_skb_pkt_type(skb)) {
 619	case HCI_ACLDATA_PKT:
 620	case HCI_COMMAND_PKT:
 621		skb_queue_tail(&h5->rel, skb);
 622		break;
 623
 624	case HCI_SCODATA_PKT:
 625	case HCI_ISODATA_PKT:
 626		skb_queue_tail(&h5->unrel, skb);
 627		break;
 628
 629	default:
 630		bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb));
 631		kfree_skb(skb);
 632		break;
 633	}
 634
 635	if (hu->serdev) {
 636		pm_runtime_get_sync(&hu->serdev->dev);
 637		pm_runtime_mark_last_busy(&hu->serdev->dev);
 638		pm_runtime_put_autosuspend(&hu->serdev->dev);
 639	}
 640
 641	return 0;
 642}
 643
 644static void h5_slip_delim(struct sk_buff *skb)
 645{
 646	const char delim = SLIP_DELIMITER;
 647
 648	skb_put_data(skb, &delim, 1);
 649}
 650
 651static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
 652{
 653	const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
 654	const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
 655
 656	switch (c) {
 657	case SLIP_DELIMITER:
 658		skb_put_data(skb, &esc_delim, 2);
 659		break;
 660	case SLIP_ESC:
 661		skb_put_data(skb, &esc_esc, 2);
 662		break;
 663	default:
 664		skb_put_data(skb, &c, 1);
 665	}
 666}
 667
 668static bool valid_packet_type(u8 type)
 669{
 670	switch (type) {
 671	case HCI_ACLDATA_PKT:
 672	case HCI_COMMAND_PKT:
 673	case HCI_SCODATA_PKT:
 674	case HCI_ISODATA_PKT:
 675	case HCI_3WIRE_LINK_PKT:
 676	case HCI_3WIRE_ACK_PKT:
 677		return true;
 678	default:
 679		return false;
 680	}
 681}
 682
 683static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
 684				      const u8 *data, size_t len)
 685{
 686	struct h5 *h5 = hu->priv;
 687	struct sk_buff *nskb;
 688	u8 hdr[4];
 689	int i;
 690
 691	if (!valid_packet_type(pkt_type)) {
 692		bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type);
 693		return NULL;
 694	}
 695
 696	/*
 697	 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
 698	 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
 699	 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
 700	 * delimiters at start and end).
 701	 */
 702	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
 703	if (!nskb)
 704		return NULL;
 705
 706	hci_skb_pkt_type(nskb) = pkt_type;
 707
 708	h5_slip_delim(nskb);
 709
 710	hdr[0] = h5->tx_ack << 3;
 711	clear_bit(H5_TX_ACK_REQ, &h5->flags);
 712
 713	/* Reliable packet? */
 714	if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
 715		hdr[0] |= 1 << 7;
 716		hdr[0] |= h5->tx_seq;
 717		h5->tx_seq = (h5->tx_seq + 1) % 8;
 718	}
 719
 720	hdr[1] = pkt_type | ((len & 0x0f) << 4);
 721	hdr[2] = len >> 4;
 722	hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
 723
 724	BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
 725	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 726	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 727	       H5_HDR_LEN(hdr));
 728
 729	for (i = 0; i < 4; i++)
 730		h5_slip_one_byte(nskb, hdr[i]);
 731
 732	for (i = 0; i < len; i++)
 733		h5_slip_one_byte(nskb, data[i]);
 734
 735	h5_slip_delim(nskb);
 736
 737	return nskb;
 738}
 739
 740static struct sk_buff *h5_dequeue(struct hci_uart *hu)
 741{
 742	struct h5 *h5 = hu->priv;
 743	unsigned long flags;
 744	struct sk_buff *skb, *nskb;
 745
 746	if (h5->sleep != H5_AWAKE) {
 747		const unsigned char wakeup_req[] = { 0x05, 0xfa };
 748
 749		if (h5->sleep == H5_WAKING_UP)
 750			return NULL;
 751
 752		h5->sleep = H5_WAKING_UP;
 753		BT_DBG("Sending wakeup request");
 754
 755		mod_timer(&h5->timer, jiffies + HZ / 100);
 756		return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
 757	}
 758
 759	skb = skb_dequeue(&h5->unrel);
 760	if (skb) {
 761		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 762				      skb->data, skb->len);
 763		if (nskb) {
 764			kfree_skb(skb);
 765			return nskb;
 766		}
 767
 768		skb_queue_head(&h5->unrel, skb);
 769		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 770	}
 771
 772	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 773
 774	if (h5->unack.qlen >= h5->tx_win)
 775		goto unlock;
 776
 777	skb = skb_dequeue(&h5->rel);
 778	if (skb) {
 779		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 780				      skb->data, skb->len);
 781		if (nskb) {
 782			__skb_queue_tail(&h5->unack, skb);
 783			mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
 784			spin_unlock_irqrestore(&h5->unack.lock, flags);
 785			return nskb;
 786		}
 787
 788		skb_queue_head(&h5->rel, skb);
 789		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 790	}
 791
 792unlock:
 793	spin_unlock_irqrestore(&h5->unack.lock, flags);
 794
 795	if (test_bit(H5_TX_ACK_REQ, &h5->flags))
 796		return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
 797
 798	return NULL;
 799}
 800
 801static int h5_flush(struct hci_uart *hu)
 802{
 803	BT_DBG("hu %p", hu);
 804	return 0;
 805}
 806
 807static const struct hci_uart_proto h5p = {
 808	.id		= HCI_UART_3WIRE,
 809	.name		= "Three-wire (H5)",
 810	.open		= h5_open,
 811	.close		= h5_close,
 812	.setup		= h5_setup,
 813	.recv		= h5_recv,
 814	.enqueue	= h5_enqueue,
 815	.dequeue	= h5_dequeue,
 816	.flush		= h5_flush,
 817};
 818
 819static int h5_serdev_probe(struct serdev_device *serdev)
 820{
 821	struct device *dev = &serdev->dev;
 822	struct h5 *h5;
 823	const struct h5_device_data *data;
 824
 825	h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
 826	if (!h5)
 827		return -ENOMEM;
 828
 
 
 829	h5->hu = &h5->serdev_hu;
 830	h5->serdev_hu.serdev = serdev;
 831	serdev_device_set_drvdata(serdev, h5);
 832
 833	if (has_acpi_companion(dev)) {
 834		const struct acpi_device_id *match;
 835
 836		match = acpi_match_device(dev->driver->acpi_match_table, dev);
 837		if (!match)
 838			return -ENODEV;
 839
 840		data = (const struct h5_device_data *)match->driver_data;
 841		h5->vnd = data->vnd;
 842		h5->id  = (char *)match->id;
 843
 844		if (h5->vnd->acpi_gpio_map)
 845			devm_acpi_dev_add_driver_gpios(dev,
 846						       h5->vnd->acpi_gpio_map);
 847	} else {
 
 
 848		data = of_device_get_match_data(dev);
 849		if (!data)
 850			return -ENODEV;
 851
 852		h5->vnd = data->vnd;
 853	}
 854
 855	if (data->driver_info & H5_INFO_WAKEUP_DISABLE)
 856		set_bit(H5_WAKEUP_DISABLE, &h5->flags);
 857
 858	h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
 859	if (IS_ERR(h5->enable_gpio))
 860		return PTR_ERR(h5->enable_gpio);
 861
 862	h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
 863						       GPIOD_OUT_LOW);
 864	if (IS_ERR(h5->device_wake_gpio))
 865		return PTR_ERR(h5->device_wake_gpio);
 866
 867	return hci_uart_register_device_priv(&h5->serdev_hu, &h5p,
 868					     h5->vnd->sizeof_priv);
 869}
 870
 871static void h5_serdev_remove(struct serdev_device *serdev)
 872{
 873	struct h5 *h5 = serdev_device_get_drvdata(serdev);
 874
 875	hci_uart_unregister_device(&h5->serdev_hu);
 876}
 877
 878static int __maybe_unused h5_serdev_suspend(struct device *dev)
 879{
 880	struct h5 *h5 = dev_get_drvdata(dev);
 881	int ret = 0;
 882
 883	if (h5->vnd && h5->vnd->suspend)
 884		ret = h5->vnd->suspend(h5);
 885
 886	return ret;
 887}
 888
 889static int __maybe_unused h5_serdev_resume(struct device *dev)
 890{
 891	struct h5 *h5 = dev_get_drvdata(dev);
 892	int ret = 0;
 893
 894	if (h5->vnd && h5->vnd->resume)
 895		ret = h5->vnd->resume(h5);
 896
 897	return ret;
 898}
 899
 900#ifdef CONFIG_BT_HCIUART_RTL
 901static int h5_btrtl_setup(struct h5 *h5)
 902{
 903	struct btrtl_device_info *btrtl_dev;
 904	struct sk_buff *skb;
 905	__le32 baudrate_data;
 906	u32 device_baudrate;
 907	unsigned int controller_baudrate;
 908	bool flow_control;
 909	int err;
 910
 911	btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
 912	if (IS_ERR(btrtl_dev))
 913		return PTR_ERR(btrtl_dev);
 914
 915	err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
 916				      &controller_baudrate, &device_baudrate,
 917				      &flow_control);
 918	if (err)
 919		goto out_free;
 920
 921	baudrate_data = cpu_to_le32(device_baudrate);
 922	skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
 923			     &baudrate_data, HCI_INIT_TIMEOUT);
 924	if (IS_ERR(skb)) {
 925		rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
 926		err = PTR_ERR(skb);
 927		goto out_free;
 928	} else {
 929		kfree_skb(skb);
 930	}
 931	/* Give the device some time to set up the new baudrate. */
 932	usleep_range(10000, 20000);
 933
 934	serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
 935	serdev_device_set_flow_control(h5->hu->serdev, flow_control);
 936
 937	if (flow_control)
 938		set_bit(H5_HW_FLOW_CONTROL, &h5->flags);
 939
 940	err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
 941	/* Give the device some time before the hci-core sends it a reset */
 942	usleep_range(10000, 20000);
 943	if (err)
 944		goto out_free;
 945
 946	btrtl_set_quirks(h5->hu->hdev, btrtl_dev);
 947
 948out_free:
 949	btrtl_free(btrtl_dev);
 950
 951	return err;
 952}
 953
 954static void h5_btrtl_open(struct h5 *h5)
 955{
 956	/*
 957	 * Since h5_btrtl_resume() does a device_reprobe() the suspend handling
 958	 * done by the hci_suspend_notifier is not necessary; it actually causes
 959	 * delays and a bunch of errors to get logged, so disable it.
 960	 */
 961	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
 962		set_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &h5->hu->flags);
 963
 964	/* Devices always start with these fixed parameters */
 965	serdev_device_set_flow_control(h5->hu->serdev, false);
 966	serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
 967	serdev_device_set_baudrate(h5->hu->serdev, 115200);
 968
 969	if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
 970		pm_runtime_set_active(&h5->hu->serdev->dev);
 971		pm_runtime_use_autosuspend(&h5->hu->serdev->dev);
 972		pm_runtime_set_autosuspend_delay(&h5->hu->serdev->dev,
 973						 SUSPEND_TIMEOUT_MS);
 974		pm_runtime_enable(&h5->hu->serdev->dev);
 975	}
 976
 977	/* The controller needs reset to startup */
 978	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 979	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 980	msleep(100);
 981
 982	/* The controller needs up to 500ms to wakeup */
 983	gpiod_set_value_cansleep(h5->enable_gpio, 1);
 984	gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
 985	msleep(500);
 986}
 987
 988static void h5_btrtl_close(struct h5 *h5)
 989{
 990	if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags))
 991		pm_runtime_disable(&h5->hu->serdev->dev);
 992
 993	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 994	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 995}
 996
 997/* Suspend/resume support. On many devices the RTL BT device loses power during
 998 * suspend/resume, causing it to lose its firmware and all state. So we simply
 999 * turn it off on suspend and reprobe on resume. This mirrors how RTL devices
1000 * are handled in the USB driver, where the BTUSB_WAKEUP_DISABLE is used which
1001 * also causes a reprobe on resume.
1002 */
1003static int h5_btrtl_suspend(struct h5 *h5)
1004{
1005	serdev_device_set_flow_control(h5->hu->serdev, false);
1006	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
1007
1008	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags))
1009		gpiod_set_value_cansleep(h5->enable_gpio, 0);
1010
1011	return 0;
1012}
1013
1014struct h5_btrtl_reprobe {
1015	struct device *dev;
1016	struct work_struct work;
1017};
1018
1019static void h5_btrtl_reprobe_worker(struct work_struct *work)
1020{
1021	struct h5_btrtl_reprobe *reprobe =
1022		container_of(work, struct h5_btrtl_reprobe, work);
1023	int ret;
1024
1025	ret = device_reprobe(reprobe->dev);
1026	if (ret && ret != -EPROBE_DEFER)
1027		dev_err(reprobe->dev, "Reprobe error %d\n", ret);
1028
1029	put_device(reprobe->dev);
1030	kfree(reprobe);
1031	module_put(THIS_MODULE);
1032}
1033
1034static int h5_btrtl_resume(struct h5 *h5)
1035{
1036	if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) {
1037		struct h5_btrtl_reprobe *reprobe;
1038
1039		reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
1040		if (!reprobe)
1041			return -ENOMEM;
1042
1043		__module_get(THIS_MODULE);
1044
1045		INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker);
1046		reprobe->dev = get_device(&h5->hu->serdev->dev);
1047		queue_work(system_long_wq, &reprobe->work);
1048	} else {
1049		gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
1050
1051		if (test_bit(H5_HW_FLOW_CONTROL, &h5->flags))
1052			serdev_device_set_flow_control(h5->hu->serdev, true);
1053	}
1054
 
 
 
1055	return 0;
1056}
1057
1058static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
1059static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
1060static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
1061static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
1062	{ "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
1063	{ "enable-gpios", &btrtl_enable_gpios, 1 },
1064	{ "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
1065	{},
1066};
1067
1068static struct h5_vnd rtl_vnd = {
1069	.setup		= h5_btrtl_setup,
1070	.open		= h5_btrtl_open,
1071	.close		= h5_btrtl_close,
1072	.suspend	= h5_btrtl_suspend,
1073	.resume		= h5_btrtl_resume,
1074	.acpi_gpio_map	= acpi_btrtl_gpios,
1075	.sizeof_priv    = sizeof(struct btrealtek_data),
1076};
1077
1078static const struct h5_device_data h5_data_rtl8822cs = {
1079	.vnd = &rtl_vnd,
1080};
1081
1082static const struct h5_device_data h5_data_rtl8723bs = {
1083	.driver_info = H5_INFO_WAKEUP_DISABLE,
1084	.vnd = &rtl_vnd,
1085};
1086#endif
1087
1088#ifdef CONFIG_ACPI
1089static const struct acpi_device_id h5_acpi_match[] = {
1090#ifdef CONFIG_BT_HCIUART_RTL
1091	{ "OBDA0623", (kernel_ulong_t)&h5_data_rtl8723bs },
1092	{ "OBDA8723", (kernel_ulong_t)&h5_data_rtl8723bs },
1093#endif
1094	{ },
1095};
1096MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
1097#endif
1098
1099static const struct dev_pm_ops h5_serdev_pm_ops = {
1100	SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume)
1101	SET_RUNTIME_PM_OPS(h5_serdev_suspend, h5_serdev_resume, NULL)
1102};
1103
1104static const struct of_device_id rtl_bluetooth_of_match[] = {
1105#ifdef CONFIG_BT_HCIUART_RTL
1106	{ .compatible = "realtek,rtl8822cs-bt",
1107	  .data = (const void *)&h5_data_rtl8822cs },
1108	{ .compatible = "realtek,rtl8723bs-bt",
1109	  .data = (const void *)&h5_data_rtl8723bs },
1110	{ .compatible = "realtek,rtl8723cs-bt",
1111	  .data = (const void *)&h5_data_rtl8723bs },
1112	{ .compatible = "realtek,rtl8723ds-bt",
1113	  .data = (const void *)&h5_data_rtl8723bs },
1114#endif
1115	{ },
1116};
1117MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match);
1118
1119static struct serdev_device_driver h5_serdev_driver = {
1120	.probe = h5_serdev_probe,
1121	.remove = h5_serdev_remove,
1122	.driver = {
1123		.name = "hci_uart_h5",
1124		.acpi_match_table = ACPI_PTR(h5_acpi_match),
1125		.pm = &h5_serdev_pm_ops,
1126		.of_match_table = rtl_bluetooth_of_match,
1127	},
1128};
1129
1130int __init h5_init(void)
1131{
1132	serdev_device_driver_register(&h5_serdev_driver);
1133	return hci_uart_register_proto(&h5p);
1134}
1135
1136int __exit h5_deinit(void)
1137{
1138	serdev_device_driver_unregister(&h5_serdev_driver);
1139	return hci_uart_unregister_proto(&h5p);
1140}
v5.9
   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	if (h5->vnd && h5->vnd->close)
 249		h5->vnd->close(h5);
 250
 251	if (!hu->serdev)
 252		kfree(h5);
 253
 254	return 0;
 255}
 256
 257static int h5_setup(struct hci_uart *hu)
 258{
 259	struct h5 *h5 = hu->priv;
 260
 261	if (h5->vnd && h5->vnd->setup)
 262		return h5->vnd->setup(h5);
 263
 264	return 0;
 265}
 266
 267static void h5_pkt_cull(struct h5 *h5)
 268{
 269	struct sk_buff *skb, *tmp;
 270	unsigned long flags;
 271	int i, to_remove;
 272	u8 seq;
 273
 274	spin_lock_irqsave(&h5->unack.lock, flags);
 275
 276	to_remove = skb_queue_len(&h5->unack);
 277	if (to_remove == 0)
 278		goto unlock;
 279
 280	seq = h5->tx_seq;
 281
 282	while (to_remove > 0) {
 283		if (h5->rx_ack == seq)
 284			break;
 285
 286		to_remove--;
 287		seq = (seq - 1) & 0x07;
 288	}
 289
 290	if (seq != h5->rx_ack)
 291		BT_ERR("Controller acked invalid packet");
 292
 293	i = 0;
 294	skb_queue_walk_safe(&h5->unack, skb, tmp) {
 295		if (i++ >= to_remove)
 296			break;
 297
 298		__skb_unlink(skb, &h5->unack);
 299		kfree_skb(skb);
 300	}
 301
 302	if (skb_queue_empty(&h5->unack))
 303		del_timer(&h5->timer);
 304
 305unlock:
 306	spin_unlock_irqrestore(&h5->unack.lock, flags);
 307}
 308
 309static void h5_handle_internal_rx(struct hci_uart *hu)
 310{
 311	struct h5 *h5 = hu->priv;
 312	const unsigned char sync_req[] = { 0x01, 0x7e };
 313	const unsigned char sync_rsp[] = { 0x02, 0x7d };
 314	unsigned char conf_req[3] = { 0x03, 0xfc };
 315	const unsigned char conf_rsp[] = { 0x04, 0x7b };
 316	const unsigned char wakeup_req[] = { 0x05, 0xfa };
 317	const unsigned char woken_req[] = { 0x06, 0xf9 };
 318	const unsigned char sleep_req[] = { 0x07, 0x78 };
 319	const unsigned char *hdr = h5->rx_skb->data;
 320	const unsigned char *data = &h5->rx_skb->data[4];
 321
 322	BT_DBG("%s", hu->hdev->name);
 323
 324	if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT)
 325		return;
 326
 327	if (H5_HDR_LEN(hdr) < 2)
 328		return;
 329
 330	conf_req[2] = h5_cfg_field(h5);
 331
 332	if (memcmp(data, sync_req, 2) == 0) {
 333		if (h5->state == H5_ACTIVE)
 334			h5_peer_reset(hu);
 335		h5_link_control(hu, sync_rsp, 2);
 336	} else if (memcmp(data, sync_rsp, 2) == 0) {
 337		if (h5->state == H5_ACTIVE)
 338			h5_peer_reset(hu);
 339		h5->state = H5_INITIALIZED;
 340		h5_link_control(hu, conf_req, 3);
 341	} else if (memcmp(data, conf_req, 2) == 0) {
 342		h5_link_control(hu, conf_rsp, 2);
 343		h5_link_control(hu, conf_req, 3);
 344	} else if (memcmp(data, conf_rsp, 2) == 0) {
 345		if (H5_HDR_LEN(hdr) > 2)
 346			h5->tx_win = (data[2] & 0x07);
 347		BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win);
 348		h5->state = H5_ACTIVE;
 349		hci_uart_init_ready(hu);
 350		return;
 351	} else if (memcmp(data, sleep_req, 2) == 0) {
 352		BT_DBG("Peer went to sleep");
 353		h5->sleep = H5_SLEEPING;
 354		return;
 355	} else if (memcmp(data, woken_req, 2) == 0) {
 356		BT_DBG("Peer woke up");
 357		h5->sleep = H5_AWAKE;
 358	} else if (memcmp(data, wakeup_req, 2) == 0) {
 359		BT_DBG("Peer requested wakeup");
 360		h5_link_control(hu, woken_req, 2);
 361		h5->sleep = H5_AWAKE;
 362	} else {
 363		BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]);
 364		return;
 365	}
 366
 367	hci_uart_tx_wakeup(hu);
 368}
 369
 370static void h5_complete_rx_pkt(struct hci_uart *hu)
 371{
 372	struct h5 *h5 = hu->priv;
 373	const unsigned char *hdr = h5->rx_skb->data;
 374
 375	if (H5_HDR_RELIABLE(hdr)) {
 376		h5->tx_ack = (h5->tx_ack + 1) % 8;
 377		set_bit(H5_TX_ACK_REQ, &h5->flags);
 378		hci_uart_tx_wakeup(hu);
 379	}
 380
 381	h5->rx_ack = H5_HDR_ACK(hdr);
 382
 383	h5_pkt_cull(h5);
 384
 385	switch (H5_HDR_PKT_TYPE(hdr)) {
 386	case HCI_EVENT_PKT:
 387	case HCI_ACLDATA_PKT:
 388	case HCI_SCODATA_PKT:
 389	case HCI_ISODATA_PKT:
 390		hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr);
 391
 392		/* Remove Three-wire header */
 393		skb_pull(h5->rx_skb, 4);
 394
 395		hci_recv_frame(hu->hdev, h5->rx_skb);
 396		h5->rx_skb = NULL;
 397
 398		break;
 399
 400	default:
 401		h5_handle_internal_rx(hu);
 402		break;
 403	}
 404
 405	h5_reset_rx(h5);
 406}
 407
 408static int h5_rx_crc(struct hci_uart *hu, unsigned char c)
 409{
 410	h5_complete_rx_pkt(hu);
 411
 412	return 0;
 413}
 414
 415static int h5_rx_payload(struct hci_uart *hu, unsigned char c)
 416{
 417	struct h5 *h5 = hu->priv;
 418	const unsigned char *hdr = h5->rx_skb->data;
 419
 420	if (H5_HDR_CRC(hdr)) {
 421		h5->rx_func = h5_rx_crc;
 422		h5->rx_pending = 2;
 423	} else {
 424		h5_complete_rx_pkt(hu);
 425	}
 426
 427	return 0;
 428}
 429
 430static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c)
 431{
 432	struct h5 *h5 = hu->priv;
 433	const unsigned char *hdr = h5->rx_skb->data;
 434
 435	BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u",
 436	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 437	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 438	       H5_HDR_LEN(hdr));
 439
 440	if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) {
 441		bt_dev_err(hu->hdev, "Invalid header checksum");
 442		h5_reset_rx(h5);
 443		return 0;
 444	}
 445
 446	if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) {
 447		bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)",
 448			   H5_HDR_SEQ(hdr), h5->tx_ack);
 
 
 449		h5_reset_rx(h5);
 450		return 0;
 451	}
 452
 453	if (h5->state != H5_ACTIVE &&
 454	    H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) {
 455		bt_dev_err(hu->hdev, "Non-link packet received in non-active state");
 456		h5_reset_rx(h5);
 457		return 0;
 458	}
 459
 460	h5->rx_func = h5_rx_payload;
 461	h5->rx_pending = H5_HDR_LEN(hdr);
 462
 463	return 0;
 464}
 465
 466static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c)
 467{
 468	struct h5 *h5 = hu->priv;
 469
 470	if (c == SLIP_DELIMITER)
 471		return 1;
 472
 473	h5->rx_func = h5_rx_3wire_hdr;
 474	h5->rx_pending = 4;
 475
 476	h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC);
 477	if (!h5->rx_skb) {
 478		bt_dev_err(hu->hdev, "Can't allocate mem for new packet");
 479		h5_reset_rx(h5);
 480		return -ENOMEM;
 481	}
 482
 483	h5->rx_skb->dev = (void *)hu->hdev;
 484
 485	return 0;
 486}
 487
 488static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c)
 489{
 490	struct h5 *h5 = hu->priv;
 491
 492	if (c == SLIP_DELIMITER)
 493		h5->rx_func = h5_rx_pkt_start;
 494
 495	return 1;
 496}
 497
 498static void h5_unslip_one_byte(struct h5 *h5, unsigned char c)
 499{
 500	const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC;
 501	const u8 *byte = &c;
 502
 503	if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) {
 504		set_bit(H5_RX_ESC, &h5->flags);
 505		return;
 506	}
 507
 508	if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) {
 509		switch (c) {
 510		case SLIP_ESC_DELIM:
 511			byte = &delim;
 512			break;
 513		case SLIP_ESC_ESC:
 514			byte = &esc;
 515			break;
 516		default:
 517			BT_ERR("Invalid esc byte 0x%02hhx", c);
 518			h5_reset_rx(h5);
 519			return;
 520		}
 521	}
 522
 523	skb_put_data(h5->rx_skb, byte, 1);
 524	h5->rx_pending--;
 525
 526	BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending);
 527}
 528
 529static void h5_reset_rx(struct h5 *h5)
 530{
 531	if (h5->rx_skb) {
 532		kfree_skb(h5->rx_skb);
 533		h5->rx_skb = NULL;
 534	}
 535
 536	h5->rx_func = h5_rx_delimiter;
 537	h5->rx_pending = 0;
 538	clear_bit(H5_RX_ESC, &h5->flags);
 539}
 540
 541static int h5_recv(struct hci_uart *hu, const void *data, int count)
 542{
 543	struct h5 *h5 = hu->priv;
 544	const unsigned char *ptr = data;
 545
 546	BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending,
 547	       count);
 548
 549	while (count > 0) {
 550		int processed;
 551
 552		if (h5->rx_pending > 0) {
 553			if (*ptr == SLIP_DELIMITER) {
 554				bt_dev_err(hu->hdev, "Too short H5 packet");
 555				h5_reset_rx(h5);
 556				continue;
 557			}
 558
 559			h5_unslip_one_byte(h5, *ptr);
 560
 561			ptr++; count--;
 562			continue;
 563		}
 564
 565		processed = h5->rx_func(hu, *ptr);
 566		if (processed < 0)
 567			return processed;
 568
 569		ptr += processed;
 570		count -= processed;
 571	}
 572
 
 
 
 
 
 
 573	return 0;
 574}
 575
 576static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 577{
 578	struct h5 *h5 = hu->priv;
 579
 580	if (skb->len > 0xfff) {
 581		bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len);
 582		kfree_skb(skb);
 583		return 0;
 584	}
 585
 586	if (h5->state != H5_ACTIVE) {
 587		bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state");
 588		kfree_skb(skb);
 589		return 0;
 590	}
 591
 592	switch (hci_skb_pkt_type(skb)) {
 593	case HCI_ACLDATA_PKT:
 594	case HCI_COMMAND_PKT:
 595		skb_queue_tail(&h5->rel, skb);
 596		break;
 597
 598	case HCI_SCODATA_PKT:
 599	case HCI_ISODATA_PKT:
 600		skb_queue_tail(&h5->unrel, skb);
 601		break;
 602
 603	default:
 604		bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb));
 605		kfree_skb(skb);
 606		break;
 607	}
 608
 
 
 
 
 
 
 609	return 0;
 610}
 611
 612static void h5_slip_delim(struct sk_buff *skb)
 613{
 614	const char delim = SLIP_DELIMITER;
 615
 616	skb_put_data(skb, &delim, 1);
 617}
 618
 619static void h5_slip_one_byte(struct sk_buff *skb, u8 c)
 620{
 621	const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM };
 622	const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC };
 623
 624	switch (c) {
 625	case SLIP_DELIMITER:
 626		skb_put_data(skb, &esc_delim, 2);
 627		break;
 628	case SLIP_ESC:
 629		skb_put_data(skb, &esc_esc, 2);
 630		break;
 631	default:
 632		skb_put_data(skb, &c, 1);
 633	}
 634}
 635
 636static bool valid_packet_type(u8 type)
 637{
 638	switch (type) {
 639	case HCI_ACLDATA_PKT:
 640	case HCI_COMMAND_PKT:
 641	case HCI_SCODATA_PKT:
 642	case HCI_ISODATA_PKT:
 643	case HCI_3WIRE_LINK_PKT:
 644	case HCI_3WIRE_ACK_PKT:
 645		return true;
 646	default:
 647		return false;
 648	}
 649}
 650
 651static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type,
 652				      const u8 *data, size_t len)
 653{
 654	struct h5 *h5 = hu->priv;
 655	struct sk_buff *nskb;
 656	u8 hdr[4];
 657	int i;
 658
 659	if (!valid_packet_type(pkt_type)) {
 660		bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type);
 661		return NULL;
 662	}
 663
 664	/*
 665	 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2
 666	 * (because bytes 0xc0 and 0xdb are escaped, worst case is when
 667	 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0
 668	 * delimiters at start and end).
 669	 */
 670	nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC);
 671	if (!nskb)
 672		return NULL;
 673
 674	hci_skb_pkt_type(nskb) = pkt_type;
 675
 676	h5_slip_delim(nskb);
 677
 678	hdr[0] = h5->tx_ack << 3;
 679	clear_bit(H5_TX_ACK_REQ, &h5->flags);
 680
 681	/* Reliable packet? */
 682	if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) {
 683		hdr[0] |= 1 << 7;
 684		hdr[0] |= h5->tx_seq;
 685		h5->tx_seq = (h5->tx_seq + 1) % 8;
 686	}
 687
 688	hdr[1] = pkt_type | ((len & 0x0f) << 4);
 689	hdr[2] = len >> 4;
 690	hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff);
 691
 692	BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u",
 693	       hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr),
 694	       H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr),
 695	       H5_HDR_LEN(hdr));
 696
 697	for (i = 0; i < 4; i++)
 698		h5_slip_one_byte(nskb, hdr[i]);
 699
 700	for (i = 0; i < len; i++)
 701		h5_slip_one_byte(nskb, data[i]);
 702
 703	h5_slip_delim(nskb);
 704
 705	return nskb;
 706}
 707
 708static struct sk_buff *h5_dequeue(struct hci_uart *hu)
 709{
 710	struct h5 *h5 = hu->priv;
 711	unsigned long flags;
 712	struct sk_buff *skb, *nskb;
 713
 714	if (h5->sleep != H5_AWAKE) {
 715		const unsigned char wakeup_req[] = { 0x05, 0xfa };
 716
 717		if (h5->sleep == H5_WAKING_UP)
 718			return NULL;
 719
 720		h5->sleep = H5_WAKING_UP;
 721		BT_DBG("Sending wakeup request");
 722
 723		mod_timer(&h5->timer, jiffies + HZ / 100);
 724		return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2);
 725	}
 726
 727	skb = skb_dequeue(&h5->unrel);
 728	if (skb) {
 729		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 730				      skb->data, skb->len);
 731		if (nskb) {
 732			kfree_skb(skb);
 733			return nskb;
 734		}
 735
 736		skb_queue_head(&h5->unrel, skb);
 737		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 738	}
 739
 740	spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING);
 741
 742	if (h5->unack.qlen >= h5->tx_win)
 743		goto unlock;
 744
 745	skb = skb_dequeue(&h5->rel);
 746	if (skb) {
 747		nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb),
 748				      skb->data, skb->len);
 749		if (nskb) {
 750			__skb_queue_tail(&h5->unack, skb);
 751			mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT);
 752			spin_unlock_irqrestore(&h5->unack.lock, flags);
 753			return nskb;
 754		}
 755
 756		skb_queue_head(&h5->rel, skb);
 757		bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed");
 758	}
 759
 760unlock:
 761	spin_unlock_irqrestore(&h5->unack.lock, flags);
 762
 763	if (test_bit(H5_TX_ACK_REQ, &h5->flags))
 764		return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0);
 765
 766	return NULL;
 767}
 768
 769static int h5_flush(struct hci_uart *hu)
 770{
 771	BT_DBG("hu %p", hu);
 772	return 0;
 773}
 774
 775static const struct hci_uart_proto h5p = {
 776	.id		= HCI_UART_3WIRE,
 777	.name		= "Three-wire (H5)",
 778	.open		= h5_open,
 779	.close		= h5_close,
 780	.setup		= h5_setup,
 781	.recv		= h5_recv,
 782	.enqueue	= h5_enqueue,
 783	.dequeue	= h5_dequeue,
 784	.flush		= h5_flush,
 785};
 786
 787static int h5_serdev_probe(struct serdev_device *serdev)
 788{
 789	struct device *dev = &serdev->dev;
 790	struct h5 *h5;
 
 791
 792	h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL);
 793	if (!h5)
 794		return -ENOMEM;
 795
 796	set_bit(HCI_UART_RESET_ON_INIT, &h5->serdev_hu.hdev_flags);
 797
 798	h5->hu = &h5->serdev_hu;
 799	h5->serdev_hu.serdev = serdev;
 800	serdev_device_set_drvdata(serdev, h5);
 801
 802	if (has_acpi_companion(dev)) {
 803		const struct acpi_device_id *match;
 804
 805		match = acpi_match_device(dev->driver->acpi_match_table, dev);
 806		if (!match)
 807			return -ENODEV;
 808
 809		h5->vnd = (const struct h5_vnd *)match->driver_data;
 
 810		h5->id  = (char *)match->id;
 811
 812		if (h5->vnd->acpi_gpio_map)
 813			devm_acpi_dev_add_driver_gpios(dev,
 814						       h5->vnd->acpi_gpio_map);
 815	} else {
 816		const void *data;
 817
 818		data = of_device_get_match_data(dev);
 819		if (!data)
 820			return -ENODEV;
 821
 822		h5->vnd = (const struct h5_vnd *)data;
 823	}
 824
 
 
 825
 826	h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
 827	if (IS_ERR(h5->enable_gpio))
 828		return PTR_ERR(h5->enable_gpio);
 829
 830	h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake",
 831						       GPIOD_OUT_LOW);
 832	if (IS_ERR(h5->device_wake_gpio))
 833		return PTR_ERR(h5->device_wake_gpio);
 834
 835	return hci_uart_register_device(&h5->serdev_hu, &h5p);
 
 836}
 837
 838static void h5_serdev_remove(struct serdev_device *serdev)
 839{
 840	struct h5 *h5 = serdev_device_get_drvdata(serdev);
 841
 842	hci_uart_unregister_device(&h5->serdev_hu);
 843}
 844
 845static int __maybe_unused h5_serdev_suspend(struct device *dev)
 846{
 847	struct h5 *h5 = dev_get_drvdata(dev);
 848	int ret = 0;
 849
 850	if (h5->vnd && h5->vnd->suspend)
 851		ret = h5->vnd->suspend(h5);
 852
 853	return ret;
 854}
 855
 856static int __maybe_unused h5_serdev_resume(struct device *dev)
 857{
 858	struct h5 *h5 = dev_get_drvdata(dev);
 859	int ret = 0;
 860
 861	if (h5->vnd && h5->vnd->resume)
 862		ret = h5->vnd->resume(h5);
 863
 864	return ret;
 865}
 866
 867#ifdef CONFIG_BT_HCIUART_RTL
 868static int h5_btrtl_setup(struct h5 *h5)
 869{
 870	struct btrtl_device_info *btrtl_dev;
 871	struct sk_buff *skb;
 872	__le32 baudrate_data;
 873	u32 device_baudrate;
 874	unsigned int controller_baudrate;
 875	bool flow_control;
 876	int err;
 877
 878	btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id);
 879	if (IS_ERR(btrtl_dev))
 880		return PTR_ERR(btrtl_dev);
 881
 882	err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev,
 883				      &controller_baudrate, &device_baudrate,
 884				      &flow_control);
 885	if (err)
 886		goto out_free;
 887
 888	baudrate_data = cpu_to_le32(device_baudrate);
 889	skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data),
 890			     &baudrate_data, HCI_INIT_TIMEOUT);
 891	if (IS_ERR(skb)) {
 892		rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n");
 893		err = PTR_ERR(skb);
 894		goto out_free;
 895	} else {
 896		kfree_skb(skb);
 897	}
 898	/* Give the device some time to set up the new baudrate. */
 899	usleep_range(10000, 20000);
 900
 901	serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate);
 902	serdev_device_set_flow_control(h5->hu->serdev, flow_control);
 903
 
 
 
 904	err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev);
 905	/* Give the device some time before the hci-core sends it a reset */
 906	usleep_range(10000, 20000);
 
 
 
 
 907
 908out_free:
 909	btrtl_free(btrtl_dev);
 910
 911	return err;
 912}
 913
 914static void h5_btrtl_open(struct h5 *h5)
 915{
 
 
 
 
 
 
 
 
 916	/* Devices always start with these fixed parameters */
 917	serdev_device_set_flow_control(h5->hu->serdev, false);
 918	serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN);
 919	serdev_device_set_baudrate(h5->hu->serdev, 115200);
 920
 
 
 
 
 
 
 
 
 
 
 
 
 
 921	/* The controller needs up to 500ms to wakeup */
 922	gpiod_set_value_cansleep(h5->enable_gpio, 1);
 923	gpiod_set_value_cansleep(h5->device_wake_gpio, 1);
 924	msleep(500);
 925}
 926
 927static void h5_btrtl_close(struct h5 *h5)
 928{
 
 
 
 929	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 930	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 931}
 932
 933/* Suspend/resume support. On many devices the RTL BT device loses power during
 934 * suspend/resume, causing it to lose its firmware and all state. So we simply
 935 * turn it off on suspend and reprobe on resume.  This mirrors how RTL devices
 936 * are handled in the USB driver, where the USB_QUIRK_RESET_RESUME is used which
 937 * also causes a reprobe on resume.
 938 */
 939static int h5_btrtl_suspend(struct h5 *h5)
 940{
 941	serdev_device_set_flow_control(h5->hu->serdev, false);
 942	gpiod_set_value_cansleep(h5->device_wake_gpio, 0);
 943	gpiod_set_value_cansleep(h5->enable_gpio, 0);
 
 
 
 944	return 0;
 945}
 946
 947struct h5_btrtl_reprobe {
 948	struct device *dev;
 949	struct work_struct work;
 950};
 951
 952static void h5_btrtl_reprobe_worker(struct work_struct *work)
 953{
 954	struct h5_btrtl_reprobe *reprobe =
 955		container_of(work, struct h5_btrtl_reprobe, work);
 956	int ret;
 957
 958	ret = device_reprobe(reprobe->dev);
 959	if (ret && ret != -EPROBE_DEFER)
 960		dev_err(reprobe->dev, "Reprobe error %d\n", ret);
 961
 962	put_device(reprobe->dev);
 963	kfree(reprobe);
 964	module_put(THIS_MODULE);
 965}
 966
 967static int h5_btrtl_resume(struct h5 *h5)
 968{
 969	struct h5_btrtl_reprobe *reprobe;
 
 970
 971	reprobe = kzalloc(sizeof(*reprobe), GFP_KERNEL);
 972	if (!reprobe)
 973		return -ENOMEM;
 
 
 
 
 
 
 
 
 974
 975	__module_get(THIS_MODULE);
 
 
 976
 977	INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker);
 978	reprobe->dev = get_device(&h5->hu->serdev->dev);
 979	queue_work(system_long_wq, &reprobe->work);
 980	return 0;
 981}
 982
 983static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false };
 984static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false };
 985static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false };
 986static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = {
 987	{ "device-wake-gpios", &btrtl_device_wake_gpios, 1 },
 988	{ "enable-gpios", &btrtl_enable_gpios, 1 },
 989	{ "host-wake-gpios", &btrtl_host_wake_gpios, 1 },
 990	{},
 991};
 992
 993static struct h5_vnd rtl_vnd = {
 994	.setup		= h5_btrtl_setup,
 995	.open		= h5_btrtl_open,
 996	.close		= h5_btrtl_close,
 997	.suspend	= h5_btrtl_suspend,
 998	.resume		= h5_btrtl_resume,
 999	.acpi_gpio_map	= acpi_btrtl_gpios,
 
 
 
 
 
 
 
 
 
 
1000};
1001#endif
1002
1003#ifdef CONFIG_ACPI
1004static const struct acpi_device_id h5_acpi_match[] = {
1005#ifdef CONFIG_BT_HCIUART_RTL
1006	{ "OBDA8723", (kernel_ulong_t)&rtl_vnd },
 
1007#endif
1008	{ },
1009};
1010MODULE_DEVICE_TABLE(acpi, h5_acpi_match);
1011#endif
1012
1013static const struct dev_pm_ops h5_serdev_pm_ops = {
1014	SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume)
 
1015};
1016
1017static const struct of_device_id rtl_bluetooth_of_match[] = {
1018#ifdef CONFIG_BT_HCIUART_RTL
1019	{ .compatible = "realtek,rtl8822cs-bt",
1020	  .data = (const void *)&rtl_vnd },
1021	{ .compatible = "realtek,rtl8723bs-bt",
1022	  .data = (const void *)&rtl_vnd },
 
 
 
 
1023#endif
1024	{ },
1025};
1026MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match);
1027
1028static struct serdev_device_driver h5_serdev_driver = {
1029	.probe = h5_serdev_probe,
1030	.remove = h5_serdev_remove,
1031	.driver = {
1032		.name = "hci_uart_h5",
1033		.acpi_match_table = ACPI_PTR(h5_acpi_match),
1034		.pm = &h5_serdev_pm_ops,
1035		.of_match_table = rtl_bluetooth_of_match,
1036	},
1037};
1038
1039int __init h5_init(void)
1040{
1041	serdev_device_driver_register(&h5_serdev_driver);
1042	return hci_uart_register_proto(&h5p);
1043}
1044
1045int __exit h5_deinit(void)
1046{
1047	serdev_device_driver_unregister(&h5_serdev_driver);
1048	return hci_uart_unregister_proto(&h5p);
1049}