drivers/bluetooth/btmtkuart.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (c) 2018 MediaTek Inc.
   3
   4 /*
   5  * Bluetooth support for MediaTek serial devices
   6  *
   7  * Author: Sean Wang <[email protected]>
   8  *
   9  */
  10
  11 #include <linux/unaligned.h>
  12 #include <linux/atomic.h>
  13 #include <linux/clk.h>
  14 #include <linux/firmware.h>
  15 #include <linux/gpio/consumer.h>
  16 #include <linux/iopoll.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/pinctrl/consumer.h>
  21 #include <linux/pm_runtime.h>
  22 #include <linux/regulator/consumer.h>
  23 #include <linux/serdev.h>
  24 #include <linux/skbuff.h>
  25 #include <linux/usb.h>
  26
  27 #include <net/bluetooth/bluetooth.h>
  28 #include <net/bluetooth/hci_core.h>
  29
  30 #include "h4_recv.h"
  31 #include "btmtk.h"
  32
  33 #define VERSION "0.2"
  34
  35 #define MTK_STP_TLR_SIZE        2
  36
  37 #define BTMTKUART_TX_STATE_ACTIVE       1
  38 #define BTMTKUART_TX_STATE_WAKEUP       2
  39 #define BTMTKUART_TX_WAIT_VND_EVT       3
  40 #define BTMTKUART_REQUIRED_WAKEUP       4
  41
  42 #define BTMTKUART_FLAG_STANDALONE_HW     BIT(0)
  43
  44 struct mtk_stp_hdr {
  45         u8      prefix;
  46         __be16  dlen;
  47         u8      cs;
  48 } __packed;
  49
  50 struct btmtkuart_data {
  51         unsigned int flags;
  52         const char *fwname;
  53 };
  54
  55 struct btmtkuart_dev {
  56         struct hci_dev *hdev;
  57         struct serdev_device *serdev;
  58
  59         struct clk *clk;
  60         struct clk *osc;
  61         struct regulator *vcc;
  62         struct gpio_desc *reset;
  63         struct gpio_desc *boot;
  64         struct pinctrl *pinctrl;
  65         struct pinctrl_state *pins_runtime;
  66         struct pinctrl_state *pins_boot;
  67         speed_t desired_speed;
  68         speed_t curr_speed;
  69
  70         struct work_struct tx_work;
  71         unsigned long tx_state;
  72         struct sk_buff_head txq;
  73
  74         struct sk_buff *rx_skb;
  75         struct sk_buff *evt_skb;
  76
  77         u8      stp_pad[6];
  78         u8      stp_cursor;
  79         u16     stp_dlen;
  80
  81         const struct btmtkuart_data *data;
  82 };
  83
  84 #define btmtkuart_is_standalone(bdev)   \
  85         ((bdev)->data->flags & BTMTKUART_FLAG_STANDALONE_HW)
  86 #define btmtkuart_is_builtin_soc(bdev)  \
  87         !((bdev)->data->flags & BTMTKUART_FLAG_STANDALONE_HW)
  88
  89 static int mtk_hci_wmt_sync(struct hci_dev *hdev,
  90                             struct btmtk_hci_wmt_params *wmt_params)
  91 {
  92         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
  93         struct btmtk_hci_wmt_evt_funcc *wmt_evt_funcc;
  94         u32 hlen, status = BTMTK_WMT_INVALID;
  95         struct btmtk_hci_wmt_evt *wmt_evt;
  96         struct btmtk_hci_wmt_cmd *wc;
  97         struct btmtk_wmt_hdr *hdr;
  98         int err;
  99
 100         /* Send the WMT command and wait until the WMT event returns */
 101         hlen = sizeof(*hdr) + wmt_params->dlen;
 102         if (hlen > 255) {
 103                 err = -EINVAL;
 104                 goto err_free_skb;
 105         }
 106
 107         wc = kzalloc(hlen, GFP_KERNEL);
 108         if (!wc) {
 109                 err = -ENOMEM;
 110                 goto err_free_skb;
 111         }
 112
 113         hdr = &wc->hdr;
 114         hdr->dir = 1;
 115         hdr->op = wmt_params->op;
 116         hdr->dlen = cpu_to_le16(wmt_params->dlen + 1);
 117         hdr->flag = wmt_params->flag;
 118         memcpy(wc->data, wmt_params->data, wmt_params->dlen);
 119
 120         set_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
 121
 122         err = __hci_cmd_send(hdev, 0xfc6f, hlen, wc);
 123         if (err < 0) {
 124                 clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
 125                 goto err_free_wc;
 126         }
 127
 128         /* The vendor specific WMT commands are all answered by a vendor
 129          * specific event and will not have the Command Status or Command
 130          * Complete as with usual HCI command flow control.
 131          *
 132          * After sending the command, wait for BTMTKUART_TX_WAIT_VND_EVT
 133          * state to be cleared. The driver specific event receive routine
 134          * will clear that state and with that indicate completion of the
 135          * WMT command.
 136          */
 137         err = wait_on_bit_timeout(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT,
 138                                   TASK_INTERRUPTIBLE, HCI_INIT_TIMEOUT);
 139         if (err == -EINTR) {
 140                 bt_dev_err(hdev, "Execution of wmt command interrupted");
 141                 clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
 142                 goto err_free_wc;
 143         }
 144
 145         if (err) {
 146                 bt_dev_err(hdev, "Execution of wmt command timed out");
 147                 clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
 148                 err = -ETIMEDOUT;
 149                 goto err_free_wc;
 150         }
 151
 152         /* Parse and handle the return WMT event */
 153         wmt_evt = (struct btmtk_hci_wmt_evt *)bdev->evt_skb->data;
 154         if (wmt_evt->whdr.op != hdr->op) {
 155                 bt_dev_err(hdev, "Wrong op received %d expected %d",
 156                            wmt_evt->whdr.op, hdr->op);
 157                 err = -EIO;
 158                 goto err_free_wc;
 159         }
 160
 161         switch (wmt_evt->whdr.op) {
 162         case BTMTK_WMT_SEMAPHORE:
 163                 if (wmt_evt->whdr.flag == 2)
 164                         status = BTMTK_WMT_PATCH_UNDONE;
 165                 else
 166                         status = BTMTK_WMT_PATCH_DONE;
 167                 break;
 168         case BTMTK_WMT_FUNC_CTRL:
 169                 wmt_evt_funcc = (struct btmtk_hci_wmt_evt_funcc *)wmt_evt;
 170                 if (be16_to_cpu(wmt_evt_funcc->status) == 0x404)
 171                         status = BTMTK_WMT_ON_DONE;
 172                 else if (be16_to_cpu(wmt_evt_funcc->status) == 0x420)
 173                         status = BTMTK_WMT_ON_PROGRESS;
 174                 else
 175                         status = BTMTK_WMT_ON_UNDONE;
 176                 break;
 177         }
 178
 179         if (wmt_params->status)
 180                 *wmt_params->status = status;
 181
 182 err_free_wc:
 183         kfree(wc);
 184 err_free_skb:
 185         kfree_skb(bdev->evt_skb);
 186         bdev->evt_skb = NULL;
 187
 188         return err;
 189 }
 190
 191 static int btmtkuart_recv_event(struct hci_dev *hdev, struct sk_buff *skb)
 192 {
 193         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 194         struct hci_event_hdr *hdr = (void *)skb->data;
 195         int err;
 196
 197         /* When someone waits for the WMT event, the skb is being cloned
 198          * and being processed the events from there then.
 199          */
 200         if (test_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state)) {
 201                 bdev->evt_skb = skb_clone(skb, GFP_KERNEL);
 202                 if (!bdev->evt_skb) {
 203                         err = -ENOMEM;
 204                         goto err_out;
 205                 }
 206         }
 207
 208         err = hci_recv_frame(hdev, skb);
 209         if (err < 0)
 210                 goto err_free_skb;
 211
 212         if (hdr->evt == HCI_EV_WMT) {
 213                 if (test_and_clear_bit(BTMTKUART_TX_WAIT_VND_EVT,
 214                                        &bdev->tx_state)) {
 215                         /* Barrier to sync with other CPUs */
 216                         smp_mb__after_atomic();
 217                         wake_up_bit(&bdev->tx_state, BTMTKUART_TX_WAIT_VND_EVT);
 218                 }
 219         }
 220
 221         return 0;
 222
 223 err_free_skb:
 224         kfree_skb(bdev->evt_skb);
 225         bdev->evt_skb = NULL;
 226
 227 err_out:
 228         return err;
 229 }
 230
 231 static const struct h4_recv_pkt mtk_recv_pkts[] = {
 232         { H4_RECV_ACL,      .recv = hci_recv_frame },
 233         { H4_RECV_SCO,      .recv = hci_recv_frame },
 234         { H4_RECV_EVENT,    .recv = btmtkuart_recv_event },
 235 };
 236
 237 static void btmtkuart_tx_work(struct work_struct *work)
 238 {
 239         struct btmtkuart_dev *bdev = container_of(work, struct btmtkuart_dev,
 240                                                    tx_work);
 241         struct serdev_device *serdev = bdev->serdev;
 242         struct hci_dev *hdev = bdev->hdev;
 243
 244         while (1) {
 245                 clear_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
 246
 247                 while (1) {
 248                         struct sk_buff *skb = skb_dequeue(&bdev->txq);
 249                         int len;
 250
 251                         if (!skb)
 252                                 break;
 253
 254                         len = serdev_device_write_buf(serdev, skb->data,
 255                                                       skb->len);
 256                         hdev->stat.byte_tx += len;
 257
 258                         skb_pull(skb, len);
 259                         if (skb->len > 0) {
 260                                 skb_queue_head(&bdev->txq, skb);
 261                                 break;
 262                         }
 263
 264                         switch (hci_skb_pkt_type(skb)) {
 265                         case HCI_COMMAND_PKT:
 266                                 hdev->stat.cmd_tx++;
 267                                 break;
 268                         case HCI_ACLDATA_PKT:
 269                                 hdev->stat.acl_tx++;
 270                                 break;
 271                         case HCI_SCODATA_PKT:
 272                                 hdev->stat.sco_tx++;
 273                                 break;
 274                         }
 275
 276                         kfree_skb(skb);
 277                 }
 278
 279                 if (!test_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state))
 280                         break;
 281         }
 282
 283         clear_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state);
 284 }
 285
 286 static void btmtkuart_tx_wakeup(struct btmtkuart_dev *bdev)
 287 {
 288         if (test_and_set_bit(BTMTKUART_TX_STATE_ACTIVE, &bdev->tx_state))
 289                 set_bit(BTMTKUART_TX_STATE_WAKEUP, &bdev->tx_state);
 290
 291         schedule_work(&bdev->tx_work);
 292 }
 293
 294 static const unsigned char *
 295 mtk_stp_split(struct btmtkuart_dev *bdev, const unsigned char *data, int count,
 296               int *sz_h4)
 297 {
 298         struct mtk_stp_hdr *shdr;
 299
 300         /* The cursor is reset when all the data of STP is consumed out */
 301         if (!bdev->stp_dlen && bdev->stp_cursor >= 6)
 302                 bdev->stp_cursor = 0;
 303
 304         /* Filling pad until all STP info is obtained */
 305         while (bdev->stp_cursor < 6 && count > 0) {
 306                 bdev->stp_pad[bdev->stp_cursor] = *data;
 307                 bdev->stp_cursor++;
 308                 data++;
 309                 count--;
 310         }
 311
 312         /* Retrieve STP info and have a sanity check */
 313         if (!bdev->stp_dlen && bdev->stp_cursor >= 6) {
 314                 shdr = (struct mtk_stp_hdr *)&bdev->stp_pad[2];
 315                 bdev->stp_dlen = be16_to_cpu(shdr->dlen) & 0x0fff;
 316
 317                 /* Resync STP when unexpected data is being read */
 318                 if (shdr->prefix != 0x80 || bdev->stp_dlen > 2048) {
 319                         bt_dev_err(bdev->hdev, "stp format unexpect (%d, %d)",
 320                                    shdr->prefix, bdev->stp_dlen);
 321                         bdev->stp_cursor = 2;
 322                         bdev->stp_dlen = 0;
 323                 }
 324         }
 325
 326         /* Directly quit when there's no data found for H4 can process */
 327         if (count <= 0)
 328                 return NULL;
 329
 330         /* Translate to how much the size of data H4 can handle so far */
 331         *sz_h4 = min_t(int, count, bdev->stp_dlen);
 332
 333         /* Update the remaining size of STP packet */
 334         bdev->stp_dlen -= *sz_h4;
 335
 336         /* Data points to STP payload which can be handled by H4 */
 337         return data;
 338 }
 339
 340 static void btmtkuart_recv(struct hci_dev *hdev, const u8 *data, size_t count)
 341 {
 342         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 343         const unsigned char *p_left = data, *p_h4;
 344         int sz_left = count, sz_h4, adv;
 345         int err;
 346
 347         while (sz_left > 0) {
 348                 /*  The serial data received from MT7622 BT controller is
 349                  *  at all time padded around with the STP header and tailer.
 350                  *
 351                  *  A full STP packet is looking like
 352                  *   -----------------------------------
 353                  *  | STP header  |  H:4   | STP tailer |
 354                  *   -----------------------------------
 355                  *  but it doesn't guarantee to contain a full H:4 packet which
 356                  *  means that it's possible for multiple STP packets forms a
 357                  *  full H:4 packet that means extra STP header + length doesn't
 358                  *  indicate a full H:4 frame, things can fragment. Whose length
 359                  *  recorded in STP header just shows up the most length the
 360                  *  H:4 engine can handle currently.
 361                  */
 362
 363                 p_h4 = mtk_stp_split(bdev, p_left, sz_left, &sz_h4);
 364                 if (!p_h4)
 365                         break;
 366
 367                 adv = p_h4 - p_left;
 368                 sz_left -= adv;
 369                 p_left += adv;
 370
 371                 bdev->rx_skb = h4_recv_buf(bdev->hdev, bdev->rx_skb, p_h4,
 372                                            sz_h4, mtk_recv_pkts,
 373                                            ARRAY_SIZE(mtk_recv_pkts));
 374                 if (IS_ERR(bdev->rx_skb)) {
 375                         err = PTR_ERR(bdev->rx_skb);
 376                         bt_dev_err(bdev->hdev,
 377                                    "Frame reassembly failed (%d)", err);
 378                         bdev->rx_skb = NULL;
 379                         return;
 380                 }
 381
 382                 sz_left -= sz_h4;
 383                 p_left += sz_h4;
 384         }
 385 }
 386
 387 static size_t btmtkuart_receive_buf(struct serdev_device *serdev,
 388                                     const u8 *data, size_t count)
 389 {
 390         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 391
 392         btmtkuart_recv(bdev->hdev, data, count);
 393
 394         bdev->hdev->stat.byte_rx += count;
 395
 396         return count;
 397 }
 398
 399 static void btmtkuart_write_wakeup(struct serdev_device *serdev)
 400 {
 401         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 402
 403         btmtkuart_tx_wakeup(bdev);
 404 }
 405
 406 static const struct serdev_device_ops btmtkuart_client_ops = {
 407         .receive_buf = btmtkuart_receive_buf,
 408         .write_wakeup = btmtkuart_write_wakeup,
 409 };
 410
 411 static int btmtkuart_open(struct hci_dev *hdev)
 412 {
 413         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 414         struct device *dev;
 415         int err;
 416
 417         err = serdev_device_open(bdev->serdev);
 418         if (err) {
 419                 bt_dev_err(hdev, "Unable to open UART device %s",
 420                            dev_name(&bdev->serdev->dev));
 421                 goto err_open;
 422         }
 423
 424         if (btmtkuart_is_standalone(bdev)) {
 425                 if (bdev->curr_speed != bdev->desired_speed)
 426                         err = serdev_device_set_baudrate(bdev->serdev,
 427                                                          115200);
 428                 else
 429                         err = serdev_device_set_baudrate(bdev->serdev,
 430                                                          bdev->desired_speed);
 431
 432                 if (err < 0) {
 433                         bt_dev_err(hdev, "Unable to set baudrate UART device %s",
 434                                    dev_name(&bdev->serdev->dev));
 435                         goto  err_serdev_close;
 436                 }
 437
 438                 serdev_device_set_flow_control(bdev->serdev, false);
 439         }
 440
 441         bdev->stp_cursor = 2;
 442         bdev->stp_dlen = 0;
 443
 444         dev = &bdev->serdev->dev;
 445
 446         /* Enable the power domain and clock the device requires */
 447         pm_runtime_enable(dev);
 448         err = pm_runtime_resume_and_get(dev);
 449         if (err < 0)
 450                 goto err_disable_rpm;
 451
 452         err = clk_prepare_enable(bdev->clk);
 453         if (err < 0)
 454                 goto err_put_rpm;
 455
 456         return 0;
 457
 458 err_put_rpm:
 459         pm_runtime_put_sync(dev);
 460 err_disable_rpm:
 461         pm_runtime_disable(dev);
 462 err_serdev_close:
 463         serdev_device_close(bdev->serdev);
 464 err_open:
 465         return err;
 466 }
 467
 468 static int btmtkuart_close(struct hci_dev *hdev)
 469 {
 470         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 471         struct device *dev = &bdev->serdev->dev;
 472
 473         /* Shutdown the clock and power domain the device requires */
 474         clk_disable_unprepare(bdev->clk);
 475         pm_runtime_put_sync(dev);
 476         pm_runtime_disable(dev);
 477
 478         serdev_device_close(bdev->serdev);
 479
 480         return 0;
 481 }
 482
 483 static int btmtkuart_flush(struct hci_dev *hdev)
 484 {
 485         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 486
 487         /* Flush any pending characters */
 488         serdev_device_write_flush(bdev->serdev);
 489         skb_queue_purge(&bdev->txq);
 490
 491         cancel_work_sync(&bdev->tx_work);
 492
 493         kfree_skb(bdev->rx_skb);
 494         bdev->rx_skb = NULL;
 495
 496         bdev->stp_cursor = 2;
 497         bdev->stp_dlen = 0;
 498
 499         return 0;
 500 }
 501
 502 static int btmtkuart_func_query(struct hci_dev *hdev)
 503 {
 504         struct btmtk_hci_wmt_params wmt_params;
 505         int status, err;
 506         u8 param = 0;
 507
 508         /* Query whether the function is enabled */
 509         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 510         wmt_params.flag = 4;
 511         wmt_params.dlen = sizeof(param);
 512         wmt_params.data = &param;
 513         wmt_params.status = &status;
 514
 515         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 516         if (err < 0) {
 517                 bt_dev_err(hdev, "Failed to query function status (%d)", err);
 518                 return err;
 519         }
 520
 521         return status;
 522 }
 523
 524 static int btmtkuart_change_baudrate(struct hci_dev *hdev)
 525 {
 526         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 527         struct btmtk_hci_wmt_params wmt_params;
 528         __le32 baudrate;
 529         u8 param;
 530         int err;
 531
 532         /* Indicate the device to enter the probe state the host is
 533          * ready to change a new baudrate.
 534          */
 535         baudrate = cpu_to_le32(bdev->desired_speed);
 536         wmt_params.op = BTMTK_WMT_HIF;
 537         wmt_params.flag = 1;
 538         wmt_params.dlen = 4;
 539         wmt_params.data = &baudrate;
 540         wmt_params.status = NULL;
 541
 542         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 543         if (err < 0) {
 544                 bt_dev_err(hdev, "Failed to device baudrate (%d)", err);
 545                 return err;
 546         }
 547
 548         err = serdev_device_set_baudrate(bdev->serdev,
 549                                          bdev->desired_speed);
 550         if (err < 0) {
 551                 bt_dev_err(hdev, "Failed to set up host baudrate (%d)",
 552                            err);
 553                 return err;
 554         }
 555
 556         serdev_device_set_flow_control(bdev->serdev, false);
 557
 558         /* Send a dummy byte 0xff to activate the new baudrate */
 559         param = 0xff;
 560         err = serdev_device_write_buf(bdev->serdev, &param, sizeof(param));
 561         if (err < 0 || err < sizeof(param))
 562                 return err;
 563
 564         serdev_device_wait_until_sent(bdev->serdev, 0);
 565
 566         /* Wait some time for the device changing baudrate done */
 567         usleep_range(20000, 22000);
 568
 569         /* Test the new baudrate */
 570         wmt_params.op = BTMTK_WMT_TEST;
 571         wmt_params.flag = 7;
 572         wmt_params.dlen = 0;
 573         wmt_params.data = NULL;
 574         wmt_params.status = NULL;
 575
 576         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 577         if (err < 0) {
 578                 bt_dev_err(hdev, "Failed to test new baudrate (%d)",
 579                            err);
 580                 return err;
 581         }
 582
 583         bdev->curr_speed = bdev->desired_speed;
 584
 585         return 0;
 586 }
 587
 588 static int btmtkuart_setup(struct hci_dev *hdev)
 589 {
 590         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 591         struct btmtk_hci_wmt_params wmt_params;
 592         ktime_t calltime, delta, rettime;
 593         struct btmtk_tci_sleep tci_sleep;
 594         unsigned long long duration;
 595         struct sk_buff *skb;
 596         int err, status;
 597         u8 param = 0x1;
 598
 599         calltime = ktime_get();
 600
 601         /* Wakeup MCUSYS is required for certain devices before we start to
 602          * do any setups.
 603          */
 604         if (test_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state)) {
 605                 wmt_params.op = BTMTK_WMT_WAKEUP;
 606                 wmt_params.flag = 3;
 607                 wmt_params.dlen = 0;
 608                 wmt_params.data = NULL;
 609                 wmt_params.status = NULL;
 610
 611                 err = mtk_hci_wmt_sync(hdev, &wmt_params);
 612                 if (err < 0) {
 613                         bt_dev_err(hdev, "Failed to wakeup the chip (%d)", err);
 614                         return err;
 615                 }
 616
 617                 clear_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
 618         }
 619
 620         if (btmtkuart_is_standalone(bdev))
 621                 btmtkuart_change_baudrate(hdev);
 622
 623         /* Query whether the firmware is already download */
 624         wmt_params.op = BTMTK_WMT_SEMAPHORE;
 625         wmt_params.flag = 1;
 626         wmt_params.dlen = 0;
 627         wmt_params.data = NULL;
 628         wmt_params.status = &status;
 629
 630         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 631         if (err < 0) {
 632                 bt_dev_err(hdev, "Failed to query firmware status (%d)", err);
 633                 return err;
 634         }
 635
 636         if (status == BTMTK_WMT_PATCH_DONE) {
 637                 bt_dev_info(hdev, "Firmware already downloaded");
 638                 goto ignore_setup_fw;
 639         }
 640
 641         /* Setup a firmware which the device definitely requires */
 642         err = btmtk_setup_firmware(hdev, bdev->data->fwname, mtk_hci_wmt_sync);
 643         if (err < 0)
 644                 return err;
 645
 646 ignore_setup_fw:
 647         /* Query whether the device is already enabled */
 648         err = readx_poll_timeout(btmtkuart_func_query, hdev, status,
 649                                  status < 0 || status != BTMTK_WMT_ON_PROGRESS,
 650                                  2000, 5000000);
 651         /* -ETIMEDOUT happens */
 652         if (err < 0)
 653                 return err;
 654
 655         /* The other errors happen in btusb_mtk_func_query */
 656         if (status < 0)
 657                 return status;
 658
 659         if (status == BTMTK_WMT_ON_DONE) {
 660                 bt_dev_info(hdev, "function already on");
 661                 goto ignore_func_on;
 662         }
 663
 664         /* Enable Bluetooth protocol */
 665         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 666         wmt_params.flag = 0;
 667         wmt_params.dlen = sizeof(param);
 668         wmt_params.data = &param;
 669         wmt_params.status = NULL;
 670
 671         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 672         if (err < 0) {
 673                 bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
 674                 return err;
 675         }
 676
 677 ignore_func_on:
 678         /* Apply the low power environment setup */
 679         tci_sleep.mode = 0x5;
 680         tci_sleep.duration = cpu_to_le16(0x640);
 681         tci_sleep.host_duration = cpu_to_le16(0x640);
 682         tci_sleep.host_wakeup_pin = 0;
 683         tci_sleep.time_compensation = 0;
 684
 685         skb = __hci_cmd_sync(hdev, 0xfc7a, sizeof(tci_sleep), &tci_sleep,
 686                              HCI_INIT_TIMEOUT);
 687         if (IS_ERR(skb)) {
 688                 err = PTR_ERR(skb);
 689                 bt_dev_err(hdev, "Failed to apply low power setting (%d)", err);
 690                 return err;
 691         }
 692         kfree_skb(skb);
 693
 694         rettime = ktime_get();
 695         delta = ktime_sub(rettime, calltime);
 696         duration = (unsigned long long)ktime_to_ns(delta) >> 10;
 697
 698         bt_dev_info(hdev, "Device setup in %llu usecs", duration);
 699
 700         return 0;
 701 }
 702
 703 static int btmtkuart_shutdown(struct hci_dev *hdev)
 704 {
 705         struct btmtk_hci_wmt_params wmt_params;
 706         u8 param = 0x0;
 707         int err;
 708
 709         /* Disable the device */
 710         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 711         wmt_params.flag = 0;
 712         wmt_params.dlen = sizeof(param);
 713         wmt_params.data = &param;
 714         wmt_params.status = NULL;
 715
 716         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 717         if (err < 0) {
 718                 bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
 719                 return err;
 720         }
 721
 722         return 0;
 723 }
 724
 725 static int btmtkuart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 726 {
 727         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 728         struct mtk_stp_hdr *shdr;
 729         int err, dlen, type = 0;
 730
 731         /* Prepend skb with frame type */
 732         memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 733
 734         /* Make sure that there is enough rooms for STP header and trailer */
 735         if (unlikely(skb_headroom(skb) < sizeof(*shdr)) ||
 736             (skb_tailroom(skb) < MTK_STP_TLR_SIZE)) {
 737                 err = pskb_expand_head(skb, sizeof(*shdr), MTK_STP_TLR_SIZE,
 738                                        GFP_ATOMIC);
 739                 if (err < 0)
 740                         return err;
 741         }
 742
 743         /* Add the STP header */
 744         dlen = skb->len;
 745         shdr = skb_push(skb, sizeof(*shdr));
 746         shdr->prefix = 0x80;
 747         shdr->dlen = cpu_to_be16((dlen & 0x0fff) | (type << 12));
 748         shdr->cs = 0;           /* MT7622 doesn't care about checksum value */
 749
 750         /* Add the STP trailer */
 751         skb_put_zero(skb, MTK_STP_TLR_SIZE);
 752
 753         skb_queue_tail(&bdev->txq, skb);
 754
 755         btmtkuart_tx_wakeup(bdev);
 756         return 0;
 757 }
 758
 759 static int btmtkuart_parse_dt(struct serdev_device *serdev)
 760 {
 761         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 762         struct device_node *node = serdev->dev.of_node;
 763         u32 speed = 921600;
 764         int err;
 765
 766         if (btmtkuart_is_standalone(bdev)) {
 767                 of_property_read_u32(node, "current-speed", &speed);
 768
 769                 bdev->desired_speed = speed;
 770
 771                 bdev->vcc = devm_regulator_get(&serdev->dev, "vcc");
 772                 if (IS_ERR(bdev->vcc)) {
 773                         err = PTR_ERR(bdev->vcc);
 774                         return err;
 775                 }
 776
 777                 bdev->osc = devm_clk_get_optional(&serdev->dev, "osc");
 778                 if (IS_ERR(bdev->osc)) {
 779                         err = PTR_ERR(bdev->osc);
 780                         return err;
 781                 }
 782
 783                 bdev->boot = devm_gpiod_get_optional(&serdev->dev, "boot",
 784                                                      GPIOD_OUT_LOW);
 785                 if (IS_ERR(bdev->boot)) {
 786                         err = PTR_ERR(bdev->boot);
 787                         return err;
 788                 }
 789
 790                 bdev->pinctrl = devm_pinctrl_get(&serdev->dev);
 791                 if (IS_ERR(bdev->pinctrl)) {
 792                         err = PTR_ERR(bdev->pinctrl);
 793                         return err;
 794                 }
 795
 796                 bdev->pins_boot = pinctrl_lookup_state(bdev->pinctrl,
 797                                                        "default");
 798                 if (IS_ERR(bdev->pins_boot) && !bdev->boot) {
 799                         err = PTR_ERR(bdev->pins_boot);
 800                         dev_err(&serdev->dev,
 801                                 "Should assign RXD to LOW at boot stage\n");
 802                         return err;
 803                 }
 804
 805                 bdev->pins_runtime = pinctrl_lookup_state(bdev->pinctrl,
 806                                                           "runtime");
 807                 if (IS_ERR(bdev->pins_runtime)) {
 808                         err = PTR_ERR(bdev->pins_runtime);
 809                         return err;
 810                 }
 811
 812                 bdev->reset = devm_gpiod_get_optional(&serdev->dev, "reset",
 813                                                       GPIOD_OUT_LOW);
 814                 if (IS_ERR(bdev->reset)) {
 815                         err = PTR_ERR(bdev->reset);
 816                         return err;
 817                 }
 818         } else if (btmtkuart_is_builtin_soc(bdev)) {
 819                 bdev->clk = devm_clk_get(&serdev->dev, "ref");
 820                 if (IS_ERR(bdev->clk))
 821                         return PTR_ERR(bdev->clk);
 822         }
 823
 824         return 0;
 825 }
 826
 827 static int btmtkuart_probe(struct serdev_device *serdev)
 828 {
 829         struct btmtkuart_dev *bdev;
 830         struct hci_dev *hdev;
 831         int err;
 832
 833         bdev = devm_kzalloc(&serdev->dev, sizeof(*bdev), GFP_KERNEL);
 834         if (!bdev)
 835                 return -ENOMEM;
 836
 837         bdev->data = of_device_get_match_data(&serdev->dev);
 838         if (!bdev->data)
 839                 return -ENODEV;
 840
 841         bdev->serdev = serdev;
 842         serdev_device_set_drvdata(serdev, bdev);
 843
 844         serdev_device_set_client_ops(serdev, &btmtkuart_client_ops);
 845
 846         err = btmtkuart_parse_dt(serdev);
 847         if (err < 0)
 848                 return err;
 849
 850         INIT_WORK(&bdev->tx_work, btmtkuart_tx_work);
 851         skb_queue_head_init(&bdev->txq);
 852
 853         /* Initialize and register HCI device */
 854         hdev = hci_alloc_dev();
 855         if (!hdev) {
 856                 dev_err(&serdev->dev, "Can't allocate HCI device\n");
 857                 return -ENOMEM;
 858         }
 859
 860         bdev->hdev = hdev;
 861
 862         hdev->bus = HCI_UART;
 863         hci_set_drvdata(hdev, bdev);
 864
 865         hdev->open     = btmtkuart_open;
 866         hdev->close    = btmtkuart_close;
 867         hdev->flush    = btmtkuart_flush;
 868         hdev->setup    = btmtkuart_setup;
 869         hdev->shutdown = btmtkuart_shutdown;
 870         hdev->send     = btmtkuart_send_frame;
 871         hdev->set_bdaddr = btmtk_set_bdaddr;
 872         SET_HCIDEV_DEV(hdev, &serdev->dev);
 873
 874         hdev->manufacturer = 70;
 875         set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
 876
 877         if (btmtkuart_is_standalone(bdev)) {
 878                 err = clk_prepare_enable(bdev->osc);
 879                 if (err < 0)
 880                         goto err_hci_free_dev;
 881
 882                 if (bdev->boot) {
 883                         gpiod_set_value_cansleep(bdev->boot, 1);
 884                 } else {
 885                         /* Switch to the specific pin state for the booting
 886                          * requires.
 887                          */
 888                         pinctrl_select_state(bdev->pinctrl, bdev->pins_boot);
 889                 }
 890
 891                 /* Power on */
 892                 err = regulator_enable(bdev->vcc);
 893                 if (err < 0)
 894                         goto err_clk_disable_unprepare;
 895
 896                 /* Reset if the reset-gpios is available otherwise the board
 897                  * -level design should be guaranteed.
 898                  */
 899                 if (bdev->reset) {
 900                         gpiod_set_value_cansleep(bdev->reset, 1);
 901                         usleep_range(1000, 2000);
 902                         gpiod_set_value_cansleep(bdev->reset, 0);
 903                 }
 904
 905                 /* Wait some time until device got ready and switch to the pin
 906                  * mode the device requires for UART transfers.
 907                  */
 908                 msleep(50);
 909
 910                 if (bdev->boot)
 911                         devm_gpiod_put(&serdev->dev, bdev->boot);
 912
 913                 pinctrl_select_state(bdev->pinctrl, bdev->pins_runtime);
 914
 915                 /* A standalone device doesn't depends on power domain on SoC,
 916                  * so mark it as no callbacks.
 917                  */
 918                 pm_runtime_no_callbacks(&serdev->dev);
 919
 920                 set_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
 921         }
 922
 923         err = hci_register_dev(hdev);
 924         if (err < 0) {
 925                 dev_err(&serdev->dev, "Can't register HCI device\n");
 926                 goto err_regulator_disable;
 927         }
 928
 929         return 0;
 930
 931 err_regulator_disable:
 932         if (btmtkuart_is_standalone(bdev))
 933                 regulator_disable(bdev->vcc);
 934 err_clk_disable_unprepare:
 935         if (btmtkuart_is_standalone(bdev))
 936                 clk_disable_unprepare(bdev->osc);
 937 err_hci_free_dev:
 938         hci_free_dev(hdev);
 939
 940         return err;
 941 }
 942
 943 static void btmtkuart_remove(struct serdev_device *serdev)
 944 {
 945         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 946         struct hci_dev *hdev = bdev->hdev;
 947
 948         if (btmtkuart_is_standalone(bdev)) {
 949                 regulator_disable(bdev->vcc);
 950                 clk_disable_unprepare(bdev->osc);
 951         }
 952
 953         hci_unregister_dev(hdev);
 954         hci_free_dev(hdev);
 955 }
 956
 957 static const struct btmtkuart_data mt7622_data __maybe_unused = {
 958         .fwname = FIRMWARE_MT7622,
 959 };
 960
 961 static const struct btmtkuart_data mt7663_data __maybe_unused = {
 962         .flags = BTMTKUART_FLAG_STANDALONE_HW,
 963         .fwname = FIRMWARE_MT7663,
 964 };
 965
 966 static const struct btmtkuart_data mt7668_data __maybe_unused = {
 967         .flags = BTMTKUART_FLAG_STANDALONE_HW,
 968         .fwname = FIRMWARE_MT7668,
 969 };
 970
 971 #ifdef CONFIG_OF
 972 static const struct of_device_id mtk_of_match_table[] = {
 973         { .compatible = "mediatek,mt7622-bluetooth", .data = &mt7622_data},
 974         { .compatible = "mediatek,mt7663u-bluetooth", .data = &mt7663_data},
 975         { .compatible = "mediatek,mt7668u-bluetooth", .data = &mt7668_data},
 976         { }
 977 };
 978 MODULE_DEVICE_TABLE(of, mtk_of_match_table);
 979 #endif
 980
 981 static struct serdev_device_driver btmtkuart_driver = {
 982         .probe = btmtkuart_probe,
 983         .remove = btmtkuart_remove,
 984         .driver = {
 985                 .name = "btmtkuart",
 986                 .of_match_table = of_match_ptr(mtk_of_match_table),
 987         },
 988 };
 989
 990 module_serdev_device_driver(btmtkuart_driver);
 991
 992 MODULE_AUTHOR("Sean Wang <[email protected]>");
 993 MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver ver " VERSION);
 994 MODULE_VERSION(VERSION);
 995 MODULE_LICENSE("GPL");