drivers/bluetooth/hci_ll.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Texas Instruments' Bluetooth HCILL UART protocol
   4  *
   5  *  HCILL (HCI Low Level) is a Texas Instruments' power management
   6  *  protocol extension to H4.
   7  *
   8  *  Copyright (C) 2007 Texas Instruments, Inc.
   9  *
  10  *  Written by Ohad Ben-Cohen <ohad@bencohen.org>
  11  *
  12  *  Acknowledgements:
  13  *  This file is based on hci_h4.c, which was written
  14  *  by Maxim Krasnyansky and Marcel Holtmann.
  15  */
  16
  17 #include <linux/module.h>
  18 #include <linux/kernel.h>
  19
  20 #include <linux/init.h>
  21 #include <linux/sched.h>
  22 #include <linux/types.h>
  23 #include <linux/fcntl.h>
  24 #include <linux/firmware.h>
  25 #include <linux/interrupt.h>
  26 #include <linux/ptrace.h>
  27 #include <linux/poll.h>
  28
  29 #include <linux/slab.h>
  30 #include <linux/errno.h>
  31 #include <linux/string.h>
  32 #include <linux/signal.h>
  33 #include <linux/ioctl.h>
  34 #include <linux/of.h>
  35 #include <linux/serdev.h>
  36 #include <linux/skbuff.h>
  37 #include <linux/ti_wilink_st.h>
  38 #include <linux/clk.h>
  39
  40 #include <net/bluetooth/bluetooth.h>
  41 #include <net/bluetooth/hci_core.h>
  42 #include <linux/gpio/consumer.h>
  43 #include <linux/nvmem-consumer.h>
  44
  45 #include "hci_uart.h"
  46
  47 /* Vendor-specific HCI commands */
  48 #define HCI_VS_WRITE_BD_ADDR                    0xfc06
  49 #define HCI_VS_UPDATE_UART_HCI_BAUDRATE         0xff36
  50
  51 /* HCILL commands */
  52 #define HCILL_GO_TO_SLEEP_IND   0x30
  53 #define HCILL_GO_TO_SLEEP_ACK   0x31
  54 #define HCILL_WAKE_UP_IND       0x32
  55 #define HCILL_WAKE_UP_ACK       0x33
  56
  57 /* HCILL states */
  58 enum hcill_states_e {
  59         HCILL_ASLEEP,
  60         HCILL_ASLEEP_TO_AWAKE,
  61         HCILL_AWAKE,
  62         HCILL_AWAKE_TO_ASLEEP
  63 };
  64
  65 struct ll_device {
  66         struct hci_uart hu;
  67         struct serdev_device *serdev;
  68         struct gpio_desc *enable_gpio;
  69         struct clk *ext_clk;
  70         bdaddr_t bdaddr;
  71 };
  72
  73 struct ll_struct {
  74         struct sk_buff *rx_skb;
  75         struct sk_buff_head txq;
  76         spinlock_t hcill_lock;          /* HCILL state lock     */
  77         unsigned long hcill_state;      /* HCILL power state    */
  78         struct sk_buff_head tx_wait_q;  /* HCILL wait queue     */
  79 };
  80
  81 /*
  82  * Builds and sends an HCILL command packet.
  83  * These are very simple packets with only 1 cmd byte
  84  */
  85 static int send_hcill_cmd(u8 cmd, struct hci_uart *hu)
  86 {
  87         int err = 0;
  88         struct sk_buff *skb = NULL;
  89         struct ll_struct *ll = hu->priv;
  90
  91         BT_DBG("hu %p cmd 0x%x", hu, cmd);
  92
  93         /* allocate packet */
  94         skb = bt_skb_alloc(1, GFP_ATOMIC);
  95         if (!skb) {
  96                 BT_ERR("cannot allocate memory for HCILL packet");
  97                 err = -ENOMEM;
  98                 goto out;
  99         }
 100
 101         /* prepare packet */
 102         skb_put_u8(skb, cmd);
 103
 104         /* send packet */
 105         skb_queue_tail(&ll->txq, skb);
 106 out:
 107         return err;
 108 }
 109
 110 /* Initialize protocol */
 111 static int ll_open(struct hci_uart *hu)
 112 {
 113         struct ll_struct *ll;
 114
 115         BT_DBG("hu %p", hu);
 116
 117         ll = kzalloc(sizeof(*ll), GFP_KERNEL);
 118         if (!ll)
 119                 return -ENOMEM;
 120
 121         skb_queue_head_init(&ll->txq);
 122         skb_queue_head_init(&ll->tx_wait_q);
 123         spin_lock_init(&ll->hcill_lock);
 124
 125         ll->hcill_state = HCILL_AWAKE;
 126
 127         hu->priv = ll;
 128
 129         if (hu->serdev) {
 130                 struct ll_device *lldev = serdev_device_get_drvdata(hu->serdev);
 131
 132                 if (!IS_ERR(lldev->ext_clk))
 133                         clk_prepare_enable(lldev->ext_clk);
 134         }
 135
 136         return 0;
 137 }
 138
 139 /* Flush protocol data */
 140 static int ll_flush(struct hci_uart *hu)
 141 {
 142         struct ll_struct *ll = hu->priv;
 143
 144         BT_DBG("hu %p", hu);
 145
 146         skb_queue_purge(&ll->tx_wait_q);
 147         skb_queue_purge(&ll->txq);
 148
 149         return 0;
 150 }
 151
 152 /* Close protocol */
 153 static int ll_close(struct hci_uart *hu)
 154 {
 155         struct ll_struct *ll = hu->priv;
 156
 157         BT_DBG("hu %p", hu);
 158
 159         skb_queue_purge(&ll->tx_wait_q);
 160         skb_queue_purge(&ll->txq);
 161
 162         kfree_skb(ll->rx_skb);
 163
 164         if (hu->serdev) {
 165                 struct ll_device *lldev = serdev_device_get_drvdata(hu->serdev);
 166
 167                 gpiod_set_value_cansleep(lldev->enable_gpio, 0);
 168
 169                 clk_disable_unprepare(lldev->ext_clk);
 170         }
 171
 172         hu->priv = NULL;
 173
 174         kfree(ll);
 175
 176         return 0;
 177 }
 178
 179 /*
 180  * internal function, which does common work of the device wake up process:
 181  * 1. places all pending packets (waiting in tx_wait_q list) in txq list.
 182  * 2. changes internal state to HCILL_AWAKE.
 183  * Note: assumes that hcill_lock spinlock is taken,
 184  * shouldn't be called otherwise!
 185  */
 186 static void __ll_do_awake(struct ll_struct *ll)
 187 {
 188         struct sk_buff *skb = NULL;
 189
 190         while ((skb = skb_dequeue(&ll->tx_wait_q)))
 191                 skb_queue_tail(&ll->txq, skb);
 192
 193         ll->hcill_state = HCILL_AWAKE;
 194 }
 195
 196 /*
 197  * Called upon a wake-up-indication from the device
 198  */
 199 static void ll_device_want_to_wakeup(struct hci_uart *hu)
 200 {
 201         unsigned long flags;
 202         struct ll_struct *ll = hu->priv;
 203
 204         BT_DBG("hu %p", hu);
 205
 206         /* lock hcill state */
 207         spin_lock_irqsave(&ll->hcill_lock, flags);
 208
 209         switch (ll->hcill_state) {
 210         case HCILL_ASLEEP_TO_AWAKE:
 211                 /*
 212                  * This state means that both the host and the BRF chip
 213                  * have simultaneously sent a wake-up-indication packet.
 214                  * Traditionally, in this case, receiving a wake-up-indication
 215                  * was enough and an additional wake-up-ack wasn't needed.
 216                  * This has changed with the BRF6350, which does require an
 217                  * explicit wake-up-ack. Other BRF versions, which do not
 218                  * require an explicit ack here, do accept it, thus it is
 219                  * perfectly safe to always send one.
 220                  */
 221                 BT_DBG("dual wake-up-indication");
 222                 fallthrough;
 223         case HCILL_ASLEEP:
 224                 /* acknowledge device wake up */
 225                 if (send_hcill_cmd(HCILL_WAKE_UP_ACK, hu) < 0) {
 226                         BT_ERR("cannot acknowledge device wake up");
 227                         goto out;
 228                 }
 229                 break;
 230         default:
 231                 /* any other state is illegal */
 232                 BT_ERR("received HCILL_WAKE_UP_IND in state %ld",
 233                        ll->hcill_state);
 234                 break;
 235         }
 236
 237         /* send pending packets and change state to HCILL_AWAKE */
 238         __ll_do_awake(ll);
 239
 240 out:
 241         spin_unlock_irqrestore(&ll->hcill_lock, flags);
 242
 243         /* actually send the packets */
 244         hci_uart_tx_wakeup(hu);
 245 }
 246
 247 /*
 248  * Called upon a sleep-indication from the device
 249  */
 250 static void ll_device_want_to_sleep(struct hci_uart *hu)
 251 {
 252         unsigned long flags;
 253         struct ll_struct *ll = hu->priv;
 254
 255         BT_DBG("hu %p", hu);
 256
 257         /* lock hcill state */
 258         spin_lock_irqsave(&ll->hcill_lock, flags);
 259
 260         /* sanity check */
 261         if (ll->hcill_state != HCILL_AWAKE)
 262                 BT_ERR("ERR: HCILL_GO_TO_SLEEP_IND in state %ld",
 263                        ll->hcill_state);
 264
 265         /* acknowledge device sleep */
 266         if (send_hcill_cmd(HCILL_GO_TO_SLEEP_ACK, hu) < 0) {
 267                 BT_ERR("cannot acknowledge device sleep");
 268                 goto out;
 269         }
 270
 271         /* update state */
 272         ll->hcill_state = HCILL_ASLEEP;
 273
 274 out:
 275         spin_unlock_irqrestore(&ll->hcill_lock, flags);
 276
 277         /* actually send the sleep ack packet */
 278         hci_uart_tx_wakeup(hu);
 279 }
 280
 281 /*
 282  * Called upon wake-up-acknowledgement from the device
 283  */
 284 static void ll_device_woke_up(struct hci_uart *hu)
 285 {
 286         unsigned long flags;
 287         struct ll_struct *ll = hu->priv;
 288
 289         BT_DBG("hu %p", hu);
 290
 291         /* lock hcill state */
 292         spin_lock_irqsave(&ll->hcill_lock, flags);
 293
 294         /* sanity check */
 295         if (ll->hcill_state != HCILL_ASLEEP_TO_AWAKE)
 296                 BT_ERR("received HCILL_WAKE_UP_ACK in state %ld",
 297                        ll->hcill_state);
 298
 299         /* send pending packets and change state to HCILL_AWAKE */
 300         __ll_do_awake(ll);
 301
 302         spin_unlock_irqrestore(&ll->hcill_lock, flags);
 303
 304         /* actually send the packets */
 305         hci_uart_tx_wakeup(hu);
 306 }
 307
 308 /* Enqueue frame for transmittion (padding, crc, etc) */
 309 /* may be called from two simultaneous tasklets */
 310 static int ll_enqueue(struct hci_uart *hu, struct sk_buff *skb)
 311 {
 312         unsigned long flags = 0;
 313         struct ll_struct *ll = hu->priv;
 314
 315         BT_DBG("hu %p skb %p", hu, skb);
 316
 317         /* Prepend skb with frame type */
 318         memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 319
 320         /* lock hcill state */
 321         spin_lock_irqsave(&ll->hcill_lock, flags);
 322
 323         /* act according to current state */
 324         switch (ll->hcill_state) {
 325         case HCILL_AWAKE:
 326                 BT_DBG("device awake, sending normally");
 327                 skb_queue_tail(&ll->txq, skb);
 328                 break;
 329         case HCILL_ASLEEP:
 330                 BT_DBG("device asleep, waking up and queueing packet");
 331                 /* save packet for later */
 332                 skb_queue_tail(&ll->tx_wait_q, skb);
 333                 /* awake device */
 334                 if (send_hcill_cmd(HCILL_WAKE_UP_IND, hu) < 0) {
 335                         BT_ERR("cannot wake up device");
 336                         break;
 337                 }
 338                 ll->hcill_state = HCILL_ASLEEP_TO_AWAKE;
 339                 break;
 340         case HCILL_ASLEEP_TO_AWAKE:
 341                 BT_DBG("device waking up, queueing packet");
 342                 /* transient state; just keep packet for later */
 343                 skb_queue_tail(&ll->tx_wait_q, skb);
 344                 break;
 345         default:
 346                 BT_ERR("illegal hcill state: %ld (losing packet)",
 347                        ll->hcill_state);
 348                 kfree_skb(skb);
 349                 break;
 350         }
 351
 352         spin_unlock_irqrestore(&ll->hcill_lock, flags);
 353
 354         return 0;
 355 }
 356
 357 static int ll_recv_frame(struct hci_dev *hdev, struct sk_buff *skb)
 358 {
 359         struct hci_uart *hu = hci_get_drvdata(hdev);
 360         struct ll_struct *ll = hu->priv;
 361
 362         switch (hci_skb_pkt_type(skb)) {
 363         case HCILL_GO_TO_SLEEP_IND:
 364                 BT_DBG("HCILL_GO_TO_SLEEP_IND packet");
 365                 ll_device_want_to_sleep(hu);
 366                 break;
 367         case HCILL_GO_TO_SLEEP_ACK:
 368                 /* shouldn't happen */
 369                 bt_dev_err(hdev, "received HCILL_GO_TO_SLEEP_ACK in state %ld",
 370                            ll->hcill_state);
 371                 break;
 372         case HCILL_WAKE_UP_IND:
 373                 BT_DBG("HCILL_WAKE_UP_IND packet");
 374                 ll_device_want_to_wakeup(hu);
 375                 break;
 376         case HCILL_WAKE_UP_ACK:
 377                 BT_DBG("HCILL_WAKE_UP_ACK packet");
 378                 ll_device_woke_up(hu);
 379                 break;
 380         }
 381
 382         kfree_skb(skb);
 383         return 0;
 384 }
 385
 386 #define LL_RECV_SLEEP_IND \
 387         .type = HCILL_GO_TO_SLEEP_IND, \
 388         .hlen = 0, \
 389         .loff = 0, \
 390         .lsize = 0, \
 391         .maxlen = 0
 392
 393 #define LL_RECV_SLEEP_ACK \
 394         .type = HCILL_GO_TO_SLEEP_ACK, \
 395         .hlen = 0, \
 396         .loff = 0, \
 397         .lsize = 0, \
 398         .maxlen = 0
 399
 400 #define LL_RECV_WAKE_IND \
 401         .type = HCILL_WAKE_UP_IND, \
 402         .hlen = 0, \
 403         .loff = 0, \
 404         .lsize = 0, \
 405         .maxlen = 0
 406
 407 #define LL_RECV_WAKE_ACK \
 408         .type = HCILL_WAKE_UP_ACK, \
 409         .hlen = 0, \
 410         .loff = 0, \
 411         .lsize = 0, \
 412         .maxlen = 0
 413
 414 static const struct h4_recv_pkt ll_recv_pkts[] = {
 415         { H4_RECV_ACL,       .recv = hci_recv_frame },
 416         { H4_RECV_SCO,       .recv = hci_recv_frame },
 417         { H4_RECV_EVENT,     .recv = hci_recv_frame },
 418         { LL_RECV_SLEEP_IND, .recv = ll_recv_frame  },
 419         { LL_RECV_SLEEP_ACK, .recv = ll_recv_frame  },
 420         { LL_RECV_WAKE_IND,  .recv = ll_recv_frame  },
 421         { LL_RECV_WAKE_ACK,  .recv = ll_recv_frame  },
 422 };
 423
 424 /* Recv data */
 425 static int ll_recv(struct hci_uart *hu, const void *data, int count)
 426 {
 427         struct ll_struct *ll = hu->priv;
 428
 429         if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
 430                 return -EUNATCH;
 431
 432         ll->rx_skb = h4_recv_buf(hu->hdev, ll->rx_skb, data, count,
 433                                  ll_recv_pkts, ARRAY_SIZE(ll_recv_pkts));
 434         if (IS_ERR(ll->rx_skb)) {
 435                 int err = PTR_ERR(ll->rx_skb);
 436                 bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
 437                 ll->rx_skb = NULL;
 438                 return err;
 439         }
 440
 441         return count;
 442 }
 443
 444 static struct sk_buff *ll_dequeue(struct hci_uart *hu)
 445 {
 446         struct ll_struct *ll = hu->priv;
 447
 448         return skb_dequeue(&ll->txq);
 449 }
 450
 451 #if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
 452 static int read_local_version(struct hci_dev *hdev)
 453 {
 454         int err = 0;
 455         unsigned short version = 0;
 456         struct sk_buff *skb;
 457         struct hci_rp_read_local_version *ver;
 458
 459         skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL,
 460                              HCI_INIT_TIMEOUT);
 461         if (IS_ERR(skb)) {
 462                 bt_dev_err(hdev, "Reading TI version information failed (%ld)",
 463                            PTR_ERR(skb));
 464                 return PTR_ERR(skb);
 465         }
 466         if (skb->len != sizeof(*ver)) {
 467                 err = -EILSEQ;
 468                 goto out;
 469         }
 470
 471         ver = (struct hci_rp_read_local_version *)skb->data;
 472         if (le16_to_cpu(ver->manufacturer) != 13) {
 473                 err = -ENODEV;
 474                 goto out;
 475         }
 476
 477         version = le16_to_cpu(ver->lmp_subver);
 478
 479 out:
 480         if (err)
 481                 bt_dev_err(hdev, "Failed to read TI version info: %d", err);
 482         kfree_skb(skb);
 483         return err ? err : version;
 484 }
 485
 486 static int send_command_from_firmware(struct ll_device *lldev,
 487                                       struct hci_command *cmd)
 488 {
 489         struct sk_buff *skb;
 490
 491         if (cmd->opcode == HCI_VS_UPDATE_UART_HCI_BAUDRATE) {
 492                 /* ignore remote change
 493                  * baud rate HCI VS command
 494                  */
 495                 bt_dev_warn(lldev->hu.hdev,
 496                             "change remote baud rate command in firmware");
 497                 return 0;
 498         }
 499         if (cmd->prefix != 1)
 500                 bt_dev_dbg(lldev->hu.hdev, "command type %d", cmd->prefix);
 501
 502         skb = __hci_cmd_sync(lldev->hu.hdev, cmd->opcode, cmd->plen,
 503                              &cmd->speed, HCI_INIT_TIMEOUT);
 504         if (IS_ERR(skb)) {
 505                 bt_dev_err(lldev->hu.hdev, "send command failed");
 506                 return PTR_ERR(skb);
 507         }
 508         kfree_skb(skb);
 509         return 0;
 510 }
 511
 512 /**
 513  * download_firmware -
 514  *      internal function which parses through the .bts firmware
 515  *      script file intreprets SEND, DELAY actions only as of now
 516  */
 517 static int download_firmware(struct ll_device *lldev)
 518 {
 519         unsigned short chip, min_ver, maj_ver;
 520         int version, err, len;
 521         unsigned char *ptr, *action_ptr;
 522         unsigned char bts_scr_name[40]; /* 40 char long bts scr name? */
 523         const struct firmware *fw;
 524         struct hci_command *cmd;
 525
 526         version = read_local_version(lldev->hu.hdev);
 527         if (version < 0)
 528                 return version;
 529
 530         chip = (version & 0x7C00) >> 10;
 531         min_ver = (version & 0x007F);
 532         maj_ver = (version & 0x0380) >> 7;
 533         if (version & 0x8000)
 534                 maj_ver |= 0x0008;
 535
 536         snprintf(bts_scr_name, sizeof(bts_scr_name),
 537                  "ti-connectivity/TIInit_%d.%d.%d.bts",
 538                  chip, maj_ver, min_ver);
 539
 540         err = request_firmware(&fw, bts_scr_name, &lldev->serdev->dev);
 541         if (err || !fw->data || !fw->size) {
 542                 bt_dev_err(lldev->hu.hdev, "request_firmware failed(errno %d) for %s",
 543                            err, bts_scr_name);
 544                 return -EINVAL;
 545         }
 546         ptr = (void *)fw->data;
 547         len = fw->size;
 548         /* bts_header to remove out magic number and
 549          * version
 550          */
 551         ptr += sizeof(struct bts_header);
 552         len -= sizeof(struct bts_header);
 553
 554         while (len > 0 && ptr) {
 555                 bt_dev_dbg(lldev->hu.hdev, " action size %d, type %d ",
 556                            ((struct bts_action *)ptr)->size,
 557                            ((struct bts_action *)ptr)->type);
 558
 559                 action_ptr = &(((struct bts_action *)ptr)->data[0]);
 560
 561                 switch (((struct bts_action *)ptr)->type) {
 562                 case ACTION_SEND_COMMAND:       /* action send */
 563                         bt_dev_dbg(lldev->hu.hdev, "S");
 564                         cmd = (struct hci_command *)action_ptr;
 565                         err = send_command_from_firmware(lldev, cmd);
 566                         if (err)
 567                                 goto out_rel_fw;
 568                         break;
 569                 case ACTION_WAIT_EVENT:  /* wait */
 570                         /* no need to wait as command was synchronous */
 571                         bt_dev_dbg(lldev->hu.hdev, "W");
 572                         break;
 573                 case ACTION_DELAY:      /* sleep */
 574                         bt_dev_info(lldev->hu.hdev, "sleep command in scr");
 575                         msleep(((struct bts_action_delay *)action_ptr)->msec);
 576                         break;
 577                 }
 578                 len -= (sizeof(struct bts_action) +
 579                         ((struct bts_action *)ptr)->size);
 580                 ptr += sizeof(struct bts_action) +
 581                         ((struct bts_action *)ptr)->size;
 582         }
 583
 584 out_rel_fw:
 585         /* fw download complete */
 586         release_firmware(fw);
 587         return err;
 588 }
 589
 590 static int ll_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
 591 {
 592         bdaddr_t bdaddr_swapped;
 593         struct sk_buff *skb;
 594
 595         /* HCI_VS_WRITE_BD_ADDR (at least on a CC2560A chip) expects the BD
 596          * address to be MSB first, but bdaddr_t has the convention of being
 597          * LSB first.
 598          */
 599         baswap(&bdaddr_swapped, bdaddr);
 600         skb = __hci_cmd_sync(hdev, HCI_VS_WRITE_BD_ADDR, sizeof(bdaddr_t),
 601                              &bdaddr_swapped, HCI_INIT_TIMEOUT);
 602         if (!IS_ERR(skb))
 603                 kfree_skb(skb);
 604
 605         return PTR_ERR_OR_ZERO(skb);
 606 }
 607
 608 static int ll_setup(struct hci_uart *hu)
 609 {
 610         int err, retry = 3;
 611         struct ll_device *lldev;
 612         struct serdev_device *serdev = hu->serdev;
 613         u32 speed;
 614
 615         if (!serdev)
 616                 return 0;
 617
 618         lldev = serdev_device_get_drvdata(serdev);
 619
 620         hu->hdev->set_bdaddr = ll_set_bdaddr;
 621
 622         serdev_device_set_flow_control(serdev, true);
 623
 624         do {
 625                 /* Reset the Bluetooth device */
 626                 gpiod_set_value_cansleep(lldev->enable_gpio, 0);
 627                 msleep(5);
 628                 gpiod_set_value_cansleep(lldev->enable_gpio, 1);
 629                 mdelay(100);
 630                 err = serdev_device_wait_for_cts(serdev, true, 200);
 631                 if (err) {
 632                         bt_dev_err(hu->hdev, "Failed to get CTS");
 633                         return err;
 634                 }
 635
 636                 err = download_firmware(lldev);
 637                 if (!err)
 638                         break;
 639
 640                 /* Toggle BT_EN and retry */
 641                 bt_dev_err(hu->hdev, "download firmware failed, retrying...");
 642         } while (retry--);
 643
 644         if (err)
 645                 return err;
 646
 647         /* Set BD address if one was specified at probe */
 648         if (!bacmp(&lldev->bdaddr, BDADDR_NONE)) {
 649                 /* This means that there was an error getting the BD address
 650                  * during probe, so mark the device as having a bad address.
 651                  */
 652                 set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);
 653         } else if (bacmp(&lldev->bdaddr, BDADDR_ANY)) {
 654                 err = ll_set_bdaddr(hu->hdev, &lldev->bdaddr);
 655                 if (err)
 656                         set_bit(HCI_QUIRK_INVALID_BDADDR, &hu->hdev->quirks);
 657         }
 658
 659         /* Operational speed if any */
 660         if (hu->oper_speed)
 661                 speed = hu->oper_speed;
 662         else if (hu->proto->oper_speed)
 663                 speed = hu->proto->oper_speed;
 664         else
 665                 speed = 0;
 666
 667         if (speed) {
 668                 __le32 speed_le = cpu_to_le32(speed);
 669                 struct sk_buff *skb;
 670
 671                 skb = __hci_cmd_sync(hu->hdev, HCI_VS_UPDATE_UART_HCI_BAUDRATE,
 672                                      sizeof(speed_le), &speed_le,
 673                                      HCI_INIT_TIMEOUT);
 674                 if (!IS_ERR(skb)) {
 675                         kfree_skb(skb);
 676                         serdev_device_set_baudrate(serdev, speed);
 677                 }
 678         }
 679
 680         return 0;
 681 }
 682
 683 static const struct hci_uart_proto llp;
 684
 685 static int hci_ti_probe(struct serdev_device *serdev)
 686 {
 687         struct hci_uart *hu;
 688         struct ll_device *lldev;
 689         struct nvmem_cell *bdaddr_cell;
 690         u32 max_speed = 3000000;
 691
 692         lldev = devm_kzalloc(&serdev->dev, sizeof(struct ll_device), GFP_KERNEL);
 693         if (!lldev)
 694                 return -ENOMEM;
 695         hu = &lldev->hu;
 696
 697         serdev_device_set_drvdata(serdev, lldev);
 698         lldev->serdev = hu->serdev = serdev;
 699
 700         lldev->enable_gpio = devm_gpiod_get_optional(&serdev->dev,
 701                                                      "enable",
 702                                                      GPIOD_OUT_LOW);
 703         if (IS_ERR(lldev->enable_gpio))
 704                 return PTR_ERR(lldev->enable_gpio);
 705
 706         lldev->ext_clk = devm_clk_get(&serdev->dev, "ext_clock");
 707         if (IS_ERR(lldev->ext_clk) && PTR_ERR(lldev->ext_clk) != -ENOENT)
 708                 return PTR_ERR(lldev->ext_clk);
 709
 710         of_property_read_u32(serdev->dev.of_node, "max-speed", &max_speed);
 711         hci_uart_set_speeds(hu, 115200, max_speed);
 712
 713         /* optional BD address from nvram */
 714         bdaddr_cell = nvmem_cell_get(&serdev->dev, "bd-address");
 715         if (IS_ERR(bdaddr_cell)) {
 716                 int err = PTR_ERR(bdaddr_cell);
 717
 718                 if (err == -EPROBE_DEFER)
 719                         return err;
 720
 721                 /* ENOENT means there is no matching nvmem cell and ENOSYS
 722                  * means that nvmem is not enabled in the kernel configuration.
 723                  */
 724                 if (err != -ENOENT && err != -ENOSYS) {
 725                         /* If there was some other error, give userspace a
 726                          * chance to fix the problem instead of failing to load
 727                          * the driver. Using BDADDR_NONE as a flag that is
 728                          * tested later in the setup function.
 729                          */
 730                         dev_warn(&serdev->dev,
 731                                  "Failed to get \"bd-address\" nvmem cell (%d)\n",
 732                                  err);
 733                         bacpy(&lldev->bdaddr, BDADDR_NONE);
 734                 }
 735         } else {
 736                 bdaddr_t *bdaddr;
 737                 size_t len;
 738
 739                 bdaddr = nvmem_cell_read(bdaddr_cell, &len);
 740                 nvmem_cell_put(bdaddr_cell);
 741                 if (IS_ERR(bdaddr)) {
 742                         dev_err(&serdev->dev, "Failed to read nvmem bd-address\n");
 743                         return PTR_ERR(bdaddr);
 744                 }
 745                 if (len != sizeof(bdaddr_t)) {
 746                         dev_err(&serdev->dev, "Invalid nvmem bd-address length\n");
 747                         kfree(bdaddr);
 748                         return -EINVAL;
 749                 }
 750
 751                 /* As per the device tree bindings, the value from nvmem is
 752                  * expected to be MSB first, but in the kernel it is expected
 753                  * that bdaddr_t is LSB first.
 754                  */
 755                 baswap(&lldev->bdaddr, bdaddr);
 756                 kfree(bdaddr);
 757         }
 758
 759         return hci_uart_register_device(hu, &llp);
 760 }
 761
 762 static void hci_ti_remove(struct serdev_device *serdev)
 763 {
 764         struct ll_device *lldev = serdev_device_get_drvdata(serdev);
 765
 766         hci_uart_unregister_device(&lldev->hu);
 767 }
 768
 769 static const struct of_device_id hci_ti_of_match[] = {
 770         { .compatible = "ti,cc2560" },
 771         { .compatible = "ti,wl1271-st" },
 772         { .compatible = "ti,wl1273-st" },
 773         { .compatible = "ti,wl1281-st" },
 774         { .compatible = "ti,wl1283-st" },
 775         { .compatible = "ti,wl1285-st" },
 776         { .compatible = "ti,wl1801-st" },
 777         { .compatible = "ti,wl1805-st" },
 778         { .compatible = "ti,wl1807-st" },
 779         { .compatible = "ti,wl1831-st" },
 780         { .compatible = "ti,wl1835-st" },
 781         { .compatible = "ti,wl1837-st" },
 782         {},
 783 };
 784 MODULE_DEVICE_TABLE(of, hci_ti_of_match);
 785
 786 static struct serdev_device_driver hci_ti_drv = {
 787         .driver         = {
 788                 .name   = "hci-ti",
 789                 .of_match_table = of_match_ptr(hci_ti_of_match),
 790         },
 791         .probe  = hci_ti_probe,
 792         .remove = hci_ti_remove,
 793 };
 794 #else
 795 #define ll_setup NULL
 796 #endif
 797
 798 static const struct hci_uart_proto llp = {
 799         .id             = HCI_UART_LL,
 800         .name           = "LL",
 801         .setup          = ll_setup,
 802         .open           = ll_open,
 803         .close          = ll_close,
 804         .recv           = ll_recv,
 805         .enqueue        = ll_enqueue,
 806         .dequeue        = ll_dequeue,
 807         .flush          = ll_flush,
 808 };
 809
 810 int __init ll_init(void)
 811 {
 812         serdev_device_driver_register(&hci_ti_drv);
 813
 814         return hci_uart_register_proto(&llp);
 815 }
 816
 817 int __exit ll_deinit(void)
 818 {
 819         serdev_device_driver_unregister(&hci_ti_drv);
 820
 821         return hci_uart_unregister_proto(&llp);
 822 }