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