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/bitrev.h> 11 #include <linux/crc-ccitt.h> 12 #include <linux/errno.h> 13 #include <linux/gpio/consumer.h> 14 #include <linux/kernel.h> 15 #include <linux/mod_devicetable.h> 16 #include <linux/of.h> 17 #include <linux/pm_runtime.h> 18 #include <linux/serdev.h> 19 #include <linux/skbuff.h> 20 21 #include <net/bluetooth/bluetooth.h> 22 #include <net/bluetooth/hci_core.h> 23 24 #include "btrtl.h" 25 #include "hci_uart.h" 26 27 #define SUSPEND_TIMEOUT_MS 6000 28 29 #define HCI_3WIRE_ACK_PKT 0 30 #define HCI_3WIRE_LINK_PKT 15 31 32 /* Sliding window size */ 33 #define H5_TX_WIN_MAX 4 34 35 #define H5_ACK_TIMEOUT msecs_to_jiffies(250) 36 #define H5_SYNC_TIMEOUT msecs_to_jiffies(100) 37 38 /* 39 * Maximum Three-wire packet: 40 * 4 byte header + max value for 12-bit length + 2 bytes for CRC 41 */ 42 #define H5_MAX_LEN (4 + 0xfff + 2) 43 44 /* Convenience macros for reading Three-wire header values */ 45 #define H5_HDR_SEQ(hdr) ((hdr)[0] & 0x07) 46 #define H5_HDR_ACK(hdr) (((hdr)[0] >> 3) & 0x07) 47 #define H5_HDR_CRC(hdr) (((hdr)[0] >> 6) & 0x01) 48 #define H5_HDR_RELIABLE(hdr) (((hdr)[0] >> 7) & 0x01) 49 #define H5_HDR_PKT_TYPE(hdr) ((hdr)[1] & 0x0f) 50 #define H5_HDR_LEN(hdr) ((((hdr)[1] >> 4) & 0x0f) + ((hdr)[2] << 4)) 51 52 #define SLIP_DELIMITER 0xc0 53 #define SLIP_ESC 0xdb 54 #define SLIP_ESC_DELIM 0xdc 55 #define SLIP_ESC_ESC 0xdd 56 57 /* H5 state flags */ 58 enum { 59 H5_RX_ESC, /* SLIP escape mode */ 60 H5_TX_ACK_REQ, /* Pending ack to send */ 61 H5_WAKEUP_DISABLE, /* Device cannot wake host */ 62 H5_HW_FLOW_CONTROL, /* Use HW flow control */ 63 H5_CRC, /* Use CRC */ 64 }; 65 66 struct h5 { 67 /* Must be the first member, hci_serdev.c expects this. */ 68 struct hci_uart serdev_hu; 69 70 struct sk_buff_head unack; /* Unack'ed packets queue */ 71 struct sk_buff_head rel; /* Reliable packets queue */ 72 struct sk_buff_head unrel; /* Unreliable packets queue */ 73 74 unsigned long flags; 75 76 struct sk_buff *rx_skb; /* Receive buffer */ 77 size_t rx_pending; /* Expecting more bytes */ 78 u8 rx_ack; /* Last ack number received */ 79 80 int (*rx_func)(struct hci_uart *hu, u8 c); 81 82 struct timer_list timer; /* Retransmission timer */ 83 struct hci_uart *hu; /* Parent HCI UART */ 84 85 u8 tx_seq; /* Next seq number to send */ 86 u8 tx_ack; /* Next ack number to send */ 87 u8 tx_win; /* Sliding window size */ 88 89 enum { 90 H5_UNINITIALIZED, 91 H5_INITIALIZED, 92 H5_ACTIVE, 93 } state; 94 95 enum { 96 H5_AWAKE, 97 H5_SLEEPING, 98 H5_WAKING_UP, 99 } sleep; 100 101 const struct h5_vnd *vnd; 102 const char *id; 103 104 struct gpio_desc *enable_gpio; 105 struct gpio_desc *device_wake_gpio; 106 }; 107 108 enum h5_driver_info { 109 H5_INFO_WAKEUP_DISABLE = BIT(0), 110 }; 111 112 struct h5_vnd { 113 int (*setup)(struct h5 *h5); 114 void (*open)(struct h5 *h5); 115 void (*close)(struct h5 *h5); 116 int (*suspend)(struct h5 *h5); 117 int (*resume)(struct h5 *h5); 118 const struct acpi_gpio_mapping *acpi_gpio_map; 119 int sizeof_priv; 120 }; 121 122 struct h5_device_data { 123 uint32_t driver_info; 124 struct h5_vnd *vnd; 125 }; 126 127 static void h5_reset_rx(struct h5 *h5); 128 129 static void h5_link_control(struct hci_uart *hu, const void *data, size_t len) 130 { 131 struct h5 *h5 = hu->priv; 132 struct sk_buff *nskb; 133 134 nskb = alloc_skb(3, GFP_ATOMIC); 135 if (!nskb) 136 return; 137 138 hci_skb_pkt_type(nskb) = HCI_3WIRE_LINK_PKT; 139 140 skb_put_data(nskb, data, len); 141 142 skb_queue_tail(&h5->unrel, nskb); 143 } 144 145 static u8 h5_cfg_field(struct h5 *h5) 146 { 147 /* Sliding window size (first 3 bits) and CRC request (fifth bit). */ 148 return (h5->tx_win & 0x07) | 0x10; 149 } 150 151 static void h5_timed_event(struct timer_list *t) 152 { 153 const unsigned char sync_req[] = { 0x01, 0x7e }; 154 unsigned char conf_req[3] = { 0x03, 0xfc }; 155 struct h5 *h5 = timer_container_of(h5, t, timer); 156 struct hci_uart *hu = h5->hu; 157 struct sk_buff *skb; 158 unsigned long flags; 159 160 BT_DBG("%s", hu->hdev->name); 161 162 if (h5->state == H5_UNINITIALIZED) 163 h5_link_control(hu, sync_req, sizeof(sync_req)); 164 165 if (h5->state == H5_INITIALIZED) { 166 conf_req[2] = h5_cfg_field(h5); 167 h5_link_control(hu, conf_req, sizeof(conf_req)); 168 } 169 170 if (h5->state != H5_ACTIVE) { 171 mod_timer(&h5->timer, jiffies + H5_SYNC_TIMEOUT); 172 goto wakeup; 173 } 174 175 if (h5->sleep != H5_AWAKE) { 176 h5->sleep = H5_SLEEPING; 177 goto wakeup; 178 } 179 180 BT_DBG("hu %p retransmitting %u pkts", hu, h5->unack.qlen); 181 182 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); 183 184 while ((skb = __skb_dequeue_tail(&h5->unack)) != NULL) { 185 h5->tx_seq = (h5->tx_seq - 1) & 0x07; 186 skb_queue_head(&h5->rel, skb); 187 } 188 189 spin_unlock_irqrestore(&h5->unack.lock, flags); 190 191 wakeup: 192 hci_uart_tx_wakeup(hu); 193 } 194 195 static void h5_peer_reset(struct hci_uart *hu) 196 { 197 struct h5 *h5 = hu->priv; 198 199 bt_dev_err(hu->hdev, "Peer device has reset"); 200 201 h5->state = H5_UNINITIALIZED; 202 203 timer_delete(&h5->timer); 204 205 skb_queue_purge(&h5->rel); 206 skb_queue_purge(&h5->unrel); 207 skb_queue_purge(&h5->unack); 208 209 h5->tx_seq = 0; 210 h5->tx_ack = 0; 211 212 /* Send reset request to upper stack */ 213 hci_reset_dev(hu->hdev); 214 } 215 216 static int h5_open(struct hci_uart *hu) 217 { 218 struct h5 *h5; 219 220 BT_DBG("hu %p", hu); 221 222 if (hu->serdev) { 223 h5 = serdev_device_get_drvdata(hu->serdev); 224 } else { 225 h5 = kzalloc_obj(*h5); 226 if (!h5) 227 return -ENOMEM; 228 } 229 230 hu->priv = h5; 231 h5->hu = hu; 232 233 skb_queue_head_init(&h5->unack); 234 skb_queue_head_init(&h5->rel); 235 skb_queue_head_init(&h5->unrel); 236 237 h5_reset_rx(h5); 238 239 timer_setup(&h5->timer, h5_timed_event, 0); 240 241 h5->tx_win = H5_TX_WIN_MAX; 242 243 if (h5->vnd && h5->vnd->open) 244 h5->vnd->open(h5); 245 246 set_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags); 247 248 /* 249 * Wait one jiffy because the UART layer won't set HCI_UART_PROTO_READY, 250 * which allows us to send link packets, until this function returns. 251 */ 252 mod_timer(&h5->timer, jiffies + 1); 253 254 return 0; 255 } 256 257 static int h5_close(struct hci_uart *hu) 258 { 259 struct h5 *h5 = hu->priv; 260 261 timer_delete_sync(&h5->timer); 262 263 skb_queue_purge(&h5->unack); 264 skb_queue_purge(&h5->rel); 265 skb_queue_purge(&h5->unrel); 266 267 kfree_skb(h5->rx_skb); 268 h5->rx_skb = NULL; 269 270 if (h5->vnd && h5->vnd->close) 271 h5->vnd->close(h5); 272 273 if (!hu->serdev) 274 kfree(h5); 275 276 return 0; 277 } 278 279 static int h5_setup(struct hci_uart *hu) 280 { 281 struct h5 *h5 = hu->priv; 282 283 if (h5->vnd && h5->vnd->setup) 284 return h5->vnd->setup(h5); 285 286 return 0; 287 } 288 289 static void h5_pkt_cull(struct h5 *h5) 290 { 291 struct sk_buff *skb, *tmp; 292 unsigned long flags; 293 int i, to_remove; 294 u8 seq; 295 296 spin_lock_irqsave(&h5->unack.lock, flags); 297 298 to_remove = skb_queue_len(&h5->unack); 299 if (to_remove == 0) 300 goto unlock; 301 302 seq = h5->tx_seq; 303 304 while (to_remove > 0) { 305 if (h5->rx_ack == seq) 306 break; 307 308 to_remove--; 309 seq = (seq - 1) & 0x07; 310 } 311 312 if (seq != h5->rx_ack) 313 BT_ERR("Controller acked invalid packet"); 314 315 i = 0; 316 skb_queue_walk_safe(&h5->unack, skb, tmp) { 317 if (i++ >= to_remove) 318 break; 319 320 __skb_unlink(skb, &h5->unack); 321 dev_kfree_skb_irq(skb); 322 } 323 324 if (skb_queue_empty(&h5->unack)) 325 timer_delete(&h5->timer); 326 327 unlock: 328 spin_unlock_irqrestore(&h5->unack.lock, flags); 329 } 330 331 static void h5_handle_internal_rx(struct hci_uart *hu) 332 { 333 struct h5 *h5 = hu->priv; 334 const unsigned char sync_req[] = { 0x01, 0x7e }; 335 const unsigned char sync_rsp[] = { 0x02, 0x7d }; 336 unsigned char conf_req[3] = { 0x03, 0xfc }; 337 const unsigned char conf_rsp[] = { 0x04, 0x7b }; 338 const unsigned char wakeup_req[] = { 0x05, 0xfa }; 339 const unsigned char woken_req[] = { 0x06, 0xf9 }; 340 const unsigned char sleep_req[] = { 0x07, 0x78 }; 341 const unsigned char *hdr = h5->rx_skb->data; 342 const unsigned char *data = &h5->rx_skb->data[4]; 343 344 BT_DBG("%s", hu->hdev->name); 345 346 if (H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) 347 return; 348 349 if (H5_HDR_LEN(hdr) < 2) 350 return; 351 352 conf_req[2] = h5_cfg_field(h5); 353 354 if (memcmp(data, sync_req, 2) == 0) { 355 if (h5->state == H5_ACTIVE) 356 h5_peer_reset(hu); 357 h5_link_control(hu, sync_rsp, 2); 358 } else if (memcmp(data, sync_rsp, 2) == 0) { 359 if (h5->state == H5_ACTIVE) 360 h5_peer_reset(hu); 361 h5->state = H5_INITIALIZED; 362 h5_link_control(hu, conf_req, 3); 363 } else if (memcmp(data, conf_req, 2) == 0) { 364 h5_link_control(hu, conf_rsp, 2); 365 h5_link_control(hu, conf_req, 3); 366 } else if (memcmp(data, conf_rsp, 2) == 0) { 367 if (H5_HDR_LEN(hdr) > 2) { 368 h5->tx_win = (data[2] & 0x07); 369 assign_bit(H5_CRC, &h5->flags, data[2] & 0x10); 370 } 371 BT_DBG("Three-wire init complete. tx_win %u", h5->tx_win); 372 h5->state = H5_ACTIVE; 373 hci_uart_init_ready(hu); 374 return; 375 } else if (memcmp(data, sleep_req, 2) == 0) { 376 BT_DBG("Peer went to sleep"); 377 h5->sleep = H5_SLEEPING; 378 return; 379 } else if (memcmp(data, woken_req, 2) == 0) { 380 BT_DBG("Peer woke up"); 381 h5->sleep = H5_AWAKE; 382 } else if (memcmp(data, wakeup_req, 2) == 0) { 383 BT_DBG("Peer requested wakeup"); 384 h5_link_control(hu, woken_req, 2); 385 h5->sleep = H5_AWAKE; 386 } else { 387 BT_DBG("Link Control: 0x%02hhx 0x%02hhx", data[0], data[1]); 388 return; 389 } 390 391 hci_uart_tx_wakeup(hu); 392 } 393 394 static void h5_complete_rx_pkt(struct hci_uart *hu) 395 { 396 struct h5 *h5 = hu->priv; 397 const unsigned char *hdr = h5->rx_skb->data; 398 399 if (H5_HDR_RELIABLE(hdr)) { 400 h5->tx_ack = (h5->tx_ack + 1) % 8; 401 set_bit(H5_TX_ACK_REQ, &h5->flags); 402 hci_uart_tx_wakeup(hu); 403 } 404 405 h5->rx_ack = H5_HDR_ACK(hdr); 406 407 h5_pkt_cull(h5); 408 409 switch (H5_HDR_PKT_TYPE(hdr)) { 410 case HCI_EVENT_PKT: 411 case HCI_ACLDATA_PKT: 412 case HCI_SCODATA_PKT: 413 case HCI_ISODATA_PKT: 414 hci_skb_pkt_type(h5->rx_skb) = H5_HDR_PKT_TYPE(hdr); 415 416 /* Remove Three-wire header */ 417 skb_pull(h5->rx_skb, 4); 418 419 hci_recv_frame(hu->hdev, h5->rx_skb); 420 h5->rx_skb = NULL; 421 422 break; 423 424 default: 425 h5_handle_internal_rx(hu); 426 break; 427 } 428 429 h5_reset_rx(h5); 430 } 431 432 static int h5_rx_crc(struct hci_uart *hu, unsigned char c) 433 { 434 struct h5 *h5 = hu->priv; 435 const unsigned char *hdr = h5->rx_skb->data; 436 u16 crc; 437 __be16 crc_be; 438 439 crc = crc_ccitt(0xffff, hdr, 4 + H5_HDR_LEN(hdr)); 440 crc = bitrev16(crc); 441 442 crc_be = cpu_to_be16(crc); 443 444 if (memcmp(&crc_be, hdr + 4 + H5_HDR_LEN(hdr), 2) != 0) { 445 bt_dev_err(hu->hdev, "Received packet with invalid CRC"); 446 h5_reset_rx(h5); 447 } else { 448 /* Remove CRC bytes */ 449 skb_trim(h5->rx_skb, 4 + H5_HDR_LEN(hdr)); 450 h5_complete_rx_pkt(hu); 451 } 452 453 return 0; 454 } 455 456 static int h5_rx_payload(struct hci_uart *hu, unsigned char c) 457 { 458 struct h5 *h5 = hu->priv; 459 const unsigned char *hdr = h5->rx_skb->data; 460 461 if (H5_HDR_CRC(hdr)) { 462 h5->rx_func = h5_rx_crc; 463 h5->rx_pending = 2; 464 } else { 465 h5_complete_rx_pkt(hu); 466 } 467 468 return 0; 469 } 470 471 static int h5_rx_3wire_hdr(struct hci_uart *hu, unsigned char c) 472 { 473 struct h5 *h5 = hu->priv; 474 const unsigned char *hdr = h5->rx_skb->data; 475 476 BT_DBG("%s rx: seq %u ack %u crc %u rel %u type %u len %u", 477 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), 478 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), 479 H5_HDR_LEN(hdr)); 480 481 if (((hdr[0] + hdr[1] + hdr[2] + hdr[3]) & 0xff) != 0xff) { 482 bt_dev_err(hu->hdev, "Invalid header checksum"); 483 h5_reset_rx(h5); 484 return 0; 485 } 486 487 if (H5_HDR_RELIABLE(hdr) && H5_HDR_SEQ(hdr) != h5->tx_ack) { 488 bt_dev_err(hu->hdev, "Out-of-order packet arrived (%u != %u)", 489 H5_HDR_SEQ(hdr), h5->tx_ack); 490 set_bit(H5_TX_ACK_REQ, &h5->flags); 491 hci_uart_tx_wakeup(hu); 492 h5_reset_rx(h5); 493 return 0; 494 } 495 496 if (h5->state != H5_ACTIVE && 497 H5_HDR_PKT_TYPE(hdr) != HCI_3WIRE_LINK_PKT) { 498 bt_dev_err(hu->hdev, "Non-link packet received in non-active state"); 499 h5_reset_rx(h5); 500 return 0; 501 } 502 503 h5->rx_func = h5_rx_payload; 504 h5->rx_pending = H5_HDR_LEN(hdr); 505 506 return 0; 507 } 508 509 static int h5_rx_pkt_start(struct hci_uart *hu, unsigned char c) 510 { 511 struct h5 *h5 = hu->priv; 512 513 if (c == SLIP_DELIMITER) 514 return 1; 515 516 h5->rx_func = h5_rx_3wire_hdr; 517 h5->rx_pending = 4; 518 519 h5->rx_skb = bt_skb_alloc(H5_MAX_LEN, GFP_ATOMIC); 520 if (!h5->rx_skb) { 521 bt_dev_err(hu->hdev, "Can't allocate mem for new packet"); 522 h5_reset_rx(h5); 523 return -ENOMEM; 524 } 525 526 h5->rx_skb->dev = (void *)hu->hdev; 527 528 return 0; 529 } 530 531 static int h5_rx_delimiter(struct hci_uart *hu, unsigned char c) 532 { 533 struct h5 *h5 = hu->priv; 534 535 if (c == SLIP_DELIMITER) 536 h5->rx_func = h5_rx_pkt_start; 537 538 return 1; 539 } 540 541 static void h5_unslip_one_byte(struct h5 *h5, unsigned char c) 542 { 543 const u8 delim = SLIP_DELIMITER, esc = SLIP_ESC; 544 const u8 *byte = &c; 545 546 if (!test_bit(H5_RX_ESC, &h5->flags) && c == SLIP_ESC) { 547 set_bit(H5_RX_ESC, &h5->flags); 548 return; 549 } 550 551 if (test_and_clear_bit(H5_RX_ESC, &h5->flags)) { 552 switch (c) { 553 case SLIP_ESC_DELIM: 554 byte = &delim; 555 break; 556 case SLIP_ESC_ESC: 557 byte = &esc; 558 break; 559 default: 560 BT_ERR("Invalid esc byte 0x%02hhx", c); 561 h5_reset_rx(h5); 562 return; 563 } 564 } 565 566 skb_put_data(h5->rx_skb, byte, 1); 567 h5->rx_pending--; 568 569 BT_DBG("unslipped 0x%02hhx, rx_pending %zu", *byte, h5->rx_pending); 570 } 571 572 static void h5_reset_rx(struct h5 *h5) 573 { 574 if (h5->rx_skb) { 575 kfree_skb(h5->rx_skb); 576 h5->rx_skb = NULL; 577 } 578 579 h5->rx_func = h5_rx_delimiter; 580 h5->rx_pending = 0; 581 clear_bit(H5_RX_ESC, &h5->flags); 582 clear_bit(H5_CRC, &h5->flags); 583 } 584 585 static int h5_recv(struct hci_uart *hu, const void *data, int count) 586 { 587 struct h5 *h5 = hu->priv; 588 const unsigned char *ptr = data; 589 590 if (!h5) 591 return -ENODEV; 592 593 BT_DBG("%s pending %zu count %d", hu->hdev->name, h5->rx_pending, 594 count); 595 596 while (count > 0) { 597 int processed; 598 599 if (h5->rx_pending > 0) { 600 if (*ptr == SLIP_DELIMITER) { 601 bt_dev_err(hu->hdev, "Too short H5 packet"); 602 h5_reset_rx(h5); 603 continue; 604 } 605 606 h5_unslip_one_byte(h5, *ptr); 607 608 ptr++; count--; 609 continue; 610 } 611 612 processed = h5->rx_func(hu, *ptr); 613 if (processed < 0) 614 return processed; 615 616 ptr += processed; 617 count -= processed; 618 } 619 620 if (hu->serdev) { 621 pm_runtime_get(&hu->serdev->dev); 622 pm_runtime_put_autosuspend(&hu->serdev->dev); 623 } 624 625 return 0; 626 } 627 628 static int h5_enqueue(struct hci_uart *hu, struct sk_buff *skb) 629 { 630 struct h5 *h5 = hu->priv; 631 632 if (skb->len > 0xfff) { 633 bt_dev_err(hu->hdev, "Packet too long (%u bytes)", skb->len); 634 kfree_skb(skb); 635 return 0; 636 } 637 638 if (h5->state != H5_ACTIVE) { 639 bt_dev_err(hu->hdev, "Ignoring HCI data in non-active state"); 640 kfree_skb(skb); 641 return 0; 642 } 643 644 switch (hci_skb_pkt_type(skb)) { 645 case HCI_ACLDATA_PKT: 646 case HCI_COMMAND_PKT: 647 skb_queue_tail(&h5->rel, skb); 648 break; 649 650 case HCI_SCODATA_PKT: 651 case HCI_ISODATA_PKT: 652 skb_queue_tail(&h5->unrel, skb); 653 break; 654 655 default: 656 bt_dev_err(hu->hdev, "Unknown packet type %u", hci_skb_pkt_type(skb)); 657 kfree_skb(skb); 658 break; 659 } 660 661 if (hu->serdev) { 662 pm_runtime_get_sync(&hu->serdev->dev); 663 pm_runtime_put_autosuspend(&hu->serdev->dev); 664 } 665 666 return 0; 667 } 668 669 static void h5_slip_delim(struct sk_buff *skb) 670 { 671 const char delim = SLIP_DELIMITER; 672 673 skb_put_data(skb, &delim, 1); 674 } 675 676 static void h5_slip_one_byte(struct sk_buff *skb, u8 c) 677 { 678 const char esc_delim[2] = { SLIP_ESC, SLIP_ESC_DELIM }; 679 const char esc_esc[2] = { SLIP_ESC, SLIP_ESC_ESC }; 680 681 switch (c) { 682 case SLIP_DELIMITER: 683 skb_put_data(skb, &esc_delim, 2); 684 break; 685 case SLIP_ESC: 686 skb_put_data(skb, &esc_esc, 2); 687 break; 688 default: 689 skb_put_data(skb, &c, 1); 690 } 691 } 692 693 static bool valid_packet_type(u8 type) 694 { 695 switch (type) { 696 case HCI_ACLDATA_PKT: 697 case HCI_COMMAND_PKT: 698 case HCI_SCODATA_PKT: 699 case HCI_ISODATA_PKT: 700 case HCI_3WIRE_LINK_PKT: 701 case HCI_3WIRE_ACK_PKT: 702 return true; 703 default: 704 return false; 705 } 706 } 707 708 static struct sk_buff *h5_prepare_pkt(struct hci_uart *hu, u8 pkt_type, 709 const u8 *data, size_t len) 710 { 711 struct h5 *h5 = hu->priv; 712 struct sk_buff *nskb; 713 u8 hdr[4]; 714 u16 crc; 715 int i; 716 717 if (!valid_packet_type(pkt_type)) { 718 bt_dev_err(hu->hdev, "Unknown packet type %u", pkt_type); 719 return NULL; 720 } 721 722 /* 723 * Max len of packet: (original len + 4 (H5 hdr) + 2 (crc)) * 2 724 * (because bytes 0xc0 and 0xdb are escaped, worst case is when 725 * the packet is all made of 0xc0 and 0xdb) + 2 (0xc0 726 * delimiters at start and end). 727 */ 728 nskb = alloc_skb((len + 6) * 2 + 2, GFP_ATOMIC); 729 if (!nskb) 730 return NULL; 731 732 hci_skb_pkt_type(nskb) = pkt_type; 733 734 h5_slip_delim(nskb); 735 736 hdr[0] = h5->tx_ack << 3; 737 clear_bit(H5_TX_ACK_REQ, &h5->flags); 738 739 /* Reliable packet? */ 740 if (pkt_type == HCI_ACLDATA_PKT || pkt_type == HCI_COMMAND_PKT) { 741 hdr[0] |= 1 << 7; 742 hdr[0] |= (test_bit(H5_CRC, &h5->flags) && 1) << 6; 743 hdr[0] |= h5->tx_seq; 744 h5->tx_seq = (h5->tx_seq + 1) % 8; 745 } 746 747 hdr[1] = pkt_type | ((len & 0x0f) << 4); 748 hdr[2] = len >> 4; 749 hdr[3] = ~((hdr[0] + hdr[1] + hdr[2]) & 0xff); 750 751 BT_DBG("%s tx: seq %u ack %u crc %u rel %u type %u len %u", 752 hu->hdev->name, H5_HDR_SEQ(hdr), H5_HDR_ACK(hdr), 753 H5_HDR_CRC(hdr), H5_HDR_RELIABLE(hdr), H5_HDR_PKT_TYPE(hdr), 754 H5_HDR_LEN(hdr)); 755 756 for (i = 0; i < 4; i++) 757 h5_slip_one_byte(nskb, hdr[i]); 758 759 for (i = 0; i < len; i++) 760 h5_slip_one_byte(nskb, data[i]); 761 762 if (H5_HDR_CRC(hdr)) { 763 crc = crc_ccitt(0xffff, hdr, 4); 764 crc = crc_ccitt(crc, data, len); 765 crc = bitrev16(crc); 766 767 h5_slip_one_byte(nskb, (crc >> 8) & 0xff); 768 h5_slip_one_byte(nskb, crc & 0xff); 769 } 770 771 h5_slip_delim(nskb); 772 773 return nskb; 774 } 775 776 static struct sk_buff *h5_dequeue(struct hci_uart *hu) 777 { 778 struct h5 *h5 = hu->priv; 779 unsigned long flags; 780 struct sk_buff *skb, *nskb; 781 782 if (h5->sleep != H5_AWAKE) { 783 const unsigned char wakeup_req[] = { 0x05, 0xfa }; 784 785 if (h5->sleep == H5_WAKING_UP) 786 return NULL; 787 788 h5->sleep = H5_WAKING_UP; 789 BT_DBG("Sending wakeup request"); 790 791 mod_timer(&h5->timer, jiffies + HZ / 100); 792 return h5_prepare_pkt(hu, HCI_3WIRE_LINK_PKT, wakeup_req, 2); 793 } 794 795 skb = skb_dequeue(&h5->unrel); 796 if (skb) { 797 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), 798 skb->data, skb->len); 799 if (nskb) { 800 kfree_skb(skb); 801 return nskb; 802 } 803 804 skb_queue_head(&h5->unrel, skb); 805 bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed"); 806 } 807 808 spin_lock_irqsave_nested(&h5->unack.lock, flags, SINGLE_DEPTH_NESTING); 809 810 if (h5->unack.qlen >= h5->tx_win) 811 goto unlock; 812 813 skb = skb_dequeue(&h5->rel); 814 if (skb) { 815 nskb = h5_prepare_pkt(hu, hci_skb_pkt_type(skb), 816 skb->data, skb->len); 817 if (nskb) { 818 __skb_queue_tail(&h5->unack, skb); 819 mod_timer(&h5->timer, jiffies + H5_ACK_TIMEOUT); 820 spin_unlock_irqrestore(&h5->unack.lock, flags); 821 return nskb; 822 } 823 824 skb_queue_head(&h5->rel, skb); 825 bt_dev_err(hu->hdev, "Could not dequeue pkt because alloc_skb failed"); 826 } 827 828 unlock: 829 spin_unlock_irqrestore(&h5->unack.lock, flags); 830 831 if (test_bit(H5_TX_ACK_REQ, &h5->flags)) 832 return h5_prepare_pkt(hu, HCI_3WIRE_ACK_PKT, NULL, 0); 833 834 return NULL; 835 } 836 837 static int h5_flush(struct hci_uart *hu) 838 { 839 BT_DBG("hu %p", hu); 840 return 0; 841 } 842 843 static const struct hci_uart_proto h5p = { 844 .id = HCI_UART_3WIRE, 845 .name = "Three-wire (H5)", 846 .open = h5_open, 847 .close = h5_close, 848 .setup = h5_setup, 849 .recv = h5_recv, 850 .enqueue = h5_enqueue, 851 .dequeue = h5_dequeue, 852 .flush = h5_flush, 853 }; 854 855 static int h5_serdev_probe(struct serdev_device *serdev) 856 { 857 struct device *dev = &serdev->dev; 858 struct h5 *h5; 859 const struct h5_device_data *data; 860 861 h5 = devm_kzalloc(dev, sizeof(*h5), GFP_KERNEL); 862 if (!h5) 863 return -ENOMEM; 864 865 h5->hu = &h5->serdev_hu; 866 h5->serdev_hu.serdev = serdev; 867 serdev_device_set_drvdata(serdev, h5); 868 869 if (has_acpi_companion(dev)) { 870 const struct acpi_device_id *match; 871 872 match = acpi_match_device(dev->driver->acpi_match_table, dev); 873 if (!match) 874 return -ENODEV; 875 876 data = (const struct h5_device_data *)match->driver_data; 877 h5->vnd = data->vnd; 878 h5->id = (char *)match->id; 879 880 if (h5->vnd->acpi_gpio_map) 881 devm_acpi_dev_add_driver_gpios(dev, 882 h5->vnd->acpi_gpio_map); 883 } else { 884 data = of_device_get_match_data(dev); 885 if (!data) 886 return -ENODEV; 887 888 h5->vnd = data->vnd; 889 } 890 891 if (data->driver_info & H5_INFO_WAKEUP_DISABLE) 892 set_bit(H5_WAKEUP_DISABLE, &h5->flags); 893 894 h5->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW); 895 if (IS_ERR(h5->enable_gpio)) 896 return PTR_ERR(h5->enable_gpio); 897 898 h5->device_wake_gpio = devm_gpiod_get_optional(dev, "device-wake", 899 GPIOD_OUT_LOW); 900 if (IS_ERR(h5->device_wake_gpio)) 901 return PTR_ERR(h5->device_wake_gpio); 902 903 return hci_uart_register_device_priv(&h5->serdev_hu, &h5p, 904 h5->vnd->sizeof_priv); 905 } 906 907 static void h5_serdev_remove(struct serdev_device *serdev) 908 { 909 struct h5 *h5 = serdev_device_get_drvdata(serdev); 910 911 hci_uart_unregister_device(&h5->serdev_hu); 912 } 913 914 static int __maybe_unused h5_serdev_suspend(struct device *dev) 915 { 916 struct h5 *h5 = dev_get_drvdata(dev); 917 int ret = 0; 918 919 if (h5->vnd && h5->vnd->suspend) 920 ret = h5->vnd->suspend(h5); 921 922 return ret; 923 } 924 925 static int __maybe_unused h5_serdev_resume(struct device *dev) 926 { 927 struct h5 *h5 = dev_get_drvdata(dev); 928 int ret = 0; 929 930 if (h5->vnd && h5->vnd->resume) 931 ret = h5->vnd->resume(h5); 932 933 return ret; 934 } 935 936 #ifdef CONFIG_BT_HCIUART_RTL 937 static int h5_btrtl_setup(struct h5 *h5) 938 { 939 struct btrtl_device_info *btrtl_dev; 940 struct sk_buff *skb; 941 __le32 baudrate_data; 942 u32 device_baudrate; 943 unsigned int controller_baudrate; 944 bool flow_control; 945 int err; 946 947 btrtl_dev = btrtl_initialize(h5->hu->hdev, h5->id); 948 if (IS_ERR(btrtl_dev)) 949 return PTR_ERR(btrtl_dev); 950 951 err = btrtl_get_uart_settings(h5->hu->hdev, btrtl_dev, 952 &controller_baudrate, &device_baudrate, 953 &flow_control); 954 if (err) 955 goto out_free; 956 957 baudrate_data = cpu_to_le32(device_baudrate); 958 skb = __hci_cmd_sync(h5->hu->hdev, 0xfc17, sizeof(baudrate_data), 959 &baudrate_data, HCI_INIT_TIMEOUT); 960 if (IS_ERR(skb)) { 961 rtl_dev_err(h5->hu->hdev, "set baud rate command failed\n"); 962 err = PTR_ERR(skb); 963 goto out_free; 964 } else { 965 kfree_skb(skb); 966 } 967 /* Give the device some time to set up the new baudrate. */ 968 usleep_range(10000, 20000); 969 970 serdev_device_set_baudrate(h5->hu->serdev, controller_baudrate); 971 serdev_device_set_flow_control(h5->hu->serdev, flow_control); 972 973 if (flow_control) 974 set_bit(H5_HW_FLOW_CONTROL, &h5->flags); 975 976 err = btrtl_download_firmware(h5->hu->hdev, btrtl_dev); 977 /* Give the device some time before the hci-core sends it a reset */ 978 usleep_range(10000, 20000); 979 if (err) 980 goto out_free; 981 982 btrtl_set_quirks(h5->hu->hdev, btrtl_dev); 983 984 out_free: 985 btrtl_free(btrtl_dev); 986 987 return err; 988 } 989 990 static void h5_btrtl_open(struct h5 *h5) 991 { 992 /* 993 * Since h5_btrtl_resume() does a device_reprobe() the suspend handling 994 * done by the hci_suspend_notifier is not necessary; it actually causes 995 * delays and a bunch of errors to get logged, so disable it. 996 */ 997 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) 998 set_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &h5->hu->flags); 999 1000 /* Devices always start with these fixed parameters */ 1001 serdev_device_set_flow_control(h5->hu->serdev, false); 1002 serdev_device_set_parity(h5->hu->serdev, SERDEV_PARITY_EVEN); 1003 serdev_device_set_baudrate(h5->hu->serdev, 115200); 1004 1005 if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) { 1006 pm_runtime_set_active(&h5->hu->serdev->dev); 1007 pm_runtime_use_autosuspend(&h5->hu->serdev->dev); 1008 pm_runtime_set_autosuspend_delay(&h5->hu->serdev->dev, 1009 SUSPEND_TIMEOUT_MS); 1010 pm_runtime_enable(&h5->hu->serdev->dev); 1011 } 1012 1013 /* The controller needs reset to startup */ 1014 gpiod_set_value_cansleep(h5->enable_gpio, 0); 1015 gpiod_set_value_cansleep(h5->device_wake_gpio, 0); 1016 msleep(100); 1017 1018 /* The controller needs up to 500ms to wakeup */ 1019 gpiod_set_value_cansleep(h5->enable_gpio, 1); 1020 gpiod_set_value_cansleep(h5->device_wake_gpio, 1); 1021 msleep(500); 1022 } 1023 1024 static void h5_btrtl_close(struct h5 *h5) 1025 { 1026 if (!test_bit(H5_WAKEUP_DISABLE, &h5->flags)) 1027 pm_runtime_disable(&h5->hu->serdev->dev); 1028 1029 gpiod_set_value_cansleep(h5->device_wake_gpio, 0); 1030 gpiod_set_value_cansleep(h5->enable_gpio, 0); 1031 } 1032 1033 /* Suspend/resume support. On many devices the RTL BT device loses power during 1034 * suspend/resume, causing it to lose its firmware and all state. So we simply 1035 * turn it off on suspend and reprobe on resume. This mirrors how RTL devices 1036 * are handled in the USB driver, where the BTUSB_WAKEUP_DISABLE is used which 1037 * also causes a reprobe on resume. 1038 */ 1039 static int h5_btrtl_suspend(struct h5 *h5) 1040 { 1041 serdev_device_set_flow_control(h5->hu->serdev, false); 1042 gpiod_set_value_cansleep(h5->device_wake_gpio, 0); 1043 1044 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) 1045 gpiod_set_value_cansleep(h5->enable_gpio, 0); 1046 1047 return 0; 1048 } 1049 1050 struct h5_btrtl_reprobe { 1051 struct device *dev; 1052 struct work_struct work; 1053 }; 1054 1055 static void h5_btrtl_reprobe_worker(struct work_struct *work) 1056 { 1057 struct h5_btrtl_reprobe *reprobe = 1058 container_of(work, struct h5_btrtl_reprobe, work); 1059 int ret; 1060 1061 ret = device_reprobe(reprobe->dev); 1062 if (ret && ret != -EPROBE_DEFER) 1063 dev_err(reprobe->dev, "Reprobe error %d\n", ret); 1064 1065 put_device(reprobe->dev); 1066 kfree(reprobe); 1067 module_put(THIS_MODULE); 1068 } 1069 1070 static int h5_btrtl_resume(struct h5 *h5) 1071 { 1072 if (test_bit(H5_WAKEUP_DISABLE, &h5->flags)) { 1073 struct h5_btrtl_reprobe *reprobe; 1074 1075 reprobe = kzalloc_obj(*reprobe); 1076 if (!reprobe) 1077 return -ENOMEM; 1078 1079 __module_get(THIS_MODULE); 1080 1081 INIT_WORK(&reprobe->work, h5_btrtl_reprobe_worker); 1082 reprobe->dev = get_device(&h5->hu->serdev->dev); 1083 queue_work(system_long_wq, &reprobe->work); 1084 } else { 1085 gpiod_set_value_cansleep(h5->device_wake_gpio, 1); 1086 1087 if (test_bit(H5_HW_FLOW_CONTROL, &h5->flags)) 1088 serdev_device_set_flow_control(h5->hu->serdev, true); 1089 } 1090 1091 return 0; 1092 } 1093 1094 static const struct acpi_gpio_params btrtl_device_wake_gpios = { 0, 0, false }; 1095 static const struct acpi_gpio_params btrtl_enable_gpios = { 1, 0, false }; 1096 static const struct acpi_gpio_params btrtl_host_wake_gpios = { 2, 0, false }; 1097 static const struct acpi_gpio_mapping acpi_btrtl_gpios[] = { 1098 { "device-wake-gpios", &btrtl_device_wake_gpios, 1 }, 1099 { "enable-gpios", &btrtl_enable_gpios, 1 }, 1100 { "host-wake-gpios", &btrtl_host_wake_gpios, 1 }, 1101 {}, 1102 }; 1103 1104 static struct h5_vnd rtl_vnd = { 1105 .setup = h5_btrtl_setup, 1106 .open = h5_btrtl_open, 1107 .close = h5_btrtl_close, 1108 .suspend = h5_btrtl_suspend, 1109 .resume = h5_btrtl_resume, 1110 .acpi_gpio_map = acpi_btrtl_gpios, 1111 .sizeof_priv = sizeof(struct btrealtek_data), 1112 }; 1113 1114 static const struct h5_device_data h5_data_rtl8822cs = { 1115 .vnd = &rtl_vnd, 1116 }; 1117 1118 static const struct h5_device_data h5_data_rtl8723bs = { 1119 .driver_info = H5_INFO_WAKEUP_DISABLE, 1120 .vnd = &rtl_vnd, 1121 }; 1122 #endif 1123 1124 #ifdef CONFIG_ACPI 1125 static const struct acpi_device_id h5_acpi_match[] = { 1126 #ifdef CONFIG_BT_HCIUART_RTL 1127 { "OBDA0623", (kernel_ulong_t)&h5_data_rtl8723bs }, 1128 { "OBDA8723", (kernel_ulong_t)&h5_data_rtl8723bs }, 1129 #endif 1130 { }, 1131 }; 1132 MODULE_DEVICE_TABLE(acpi, h5_acpi_match); 1133 #endif 1134 1135 static const struct dev_pm_ops h5_serdev_pm_ops = { 1136 SET_SYSTEM_SLEEP_PM_OPS(h5_serdev_suspend, h5_serdev_resume) 1137 SET_RUNTIME_PM_OPS(h5_serdev_suspend, h5_serdev_resume, NULL) 1138 }; 1139 1140 static const struct of_device_id rtl_bluetooth_of_match[] = { 1141 #ifdef CONFIG_BT_HCIUART_RTL 1142 { .compatible = "realtek,rtl8822cs-bt", 1143 .data = (const void *)&h5_data_rtl8822cs }, 1144 { .compatible = "realtek,rtl8723bs-bt", 1145 .data = (const void *)&h5_data_rtl8723bs }, 1146 { .compatible = "realtek,rtl8723cs-bt", 1147 .data = (const void *)&h5_data_rtl8723bs }, 1148 { .compatible = "realtek,rtl8723ds-bt", 1149 .data = (const void *)&h5_data_rtl8723bs }, 1150 #endif 1151 { }, 1152 }; 1153 MODULE_DEVICE_TABLE(of, rtl_bluetooth_of_match); 1154 1155 static struct serdev_device_driver h5_serdev_driver = { 1156 .probe = h5_serdev_probe, 1157 .remove = h5_serdev_remove, 1158 .driver = { 1159 .name = "hci_uart_h5", 1160 .acpi_match_table = ACPI_PTR(h5_acpi_match), 1161 .pm = &h5_serdev_pm_ops, 1162 .of_match_table = rtl_bluetooth_of_match, 1163 }, 1164 }; 1165 1166 int __init h5_init(void) 1167 { 1168 serdev_device_driver_register(&h5_serdev_driver); 1169 return hci_uart_register_proto(&h5p); 1170 } 1171 1172 int __exit h5_deinit(void) 1173 { 1174 serdev_device_driver_unregister(&h5_serdev_driver); 1175 return hci_uart_unregister_proto(&h5p); 1176 } 1177