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