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 <sean.wang@mediatek.com>
   8  *
   9  */
  10
  11 #include <asm/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/of_device.h>
  21 #include <linux/pinctrl/consumer.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/regulator/consumer.h>
  24 #include <linux/serdev.h>
  25 #include <linux/skbuff.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         /* Tranlate 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 int 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 err;
 380                 }
 381
 382                 sz_left -= sz_h4;
 383                 p_left += sz_h4;
 384         }
 385
 386         return 0;
 387 }
 388
 389 static int btmtkuart_receive_buf(struct serdev_device *serdev, const u8 *data,
 390                                  size_t count)
 391 {
 392         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 393         int err;
 394
 395         err = btmtkuart_recv(bdev->hdev, data, count);
 396         if (err < 0)
 397                 return err;
 398
 399         bdev->hdev->stat.byte_rx += count;
 400
 401         return count;
 402 }
 403
 404 static void btmtkuart_write_wakeup(struct serdev_device *serdev)
 405 {
 406         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 407
 408         btmtkuart_tx_wakeup(bdev);
 409 }
 410
 411 static const struct serdev_device_ops btmtkuart_client_ops = {
 412         .receive_buf = btmtkuart_receive_buf,
 413         .write_wakeup = btmtkuart_write_wakeup,
 414 };
 415
 416 static int btmtkuart_open(struct hci_dev *hdev)
 417 {
 418         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 419         struct device *dev;
 420         int err;
 421
 422         err = serdev_device_open(bdev->serdev);
 423         if (err) {
 424                 bt_dev_err(hdev, "Unable to open UART device %s",
 425                            dev_name(&bdev->serdev->dev));
 426                 goto err_open;
 427         }
 428
 429         if (btmtkuart_is_standalone(bdev)) {
 430                 if (bdev->curr_speed != bdev->desired_speed)
 431                         err = serdev_device_set_baudrate(bdev->serdev,
 432                                                          115200);
 433                 else
 434                         err = serdev_device_set_baudrate(bdev->serdev,
 435                                                          bdev->desired_speed);
 436
 437                 if (err < 0) {
 438                         bt_dev_err(hdev, "Unable to set baudrate UART device %s",
 439                                    dev_name(&bdev->serdev->dev));
 440                         goto  err_serdev_close;
 441                 }
 442
 443                 serdev_device_set_flow_control(bdev->serdev, false);
 444         }
 445
 446         bdev->stp_cursor = 2;
 447         bdev->stp_dlen = 0;
 448
 449         dev = &bdev->serdev->dev;
 450
 451         /* Enable the power domain and clock the device requires */
 452         pm_runtime_enable(dev);
 453         err = pm_runtime_resume_and_get(dev);
 454         if (err < 0)
 455                 goto err_disable_rpm;
 456
 457         err = clk_prepare_enable(bdev->clk);
 458         if (err < 0)
 459                 goto err_put_rpm;
 460
 461         return 0;
 462
 463 err_put_rpm:
 464         pm_runtime_put_sync(dev);
 465 err_disable_rpm:
 466         pm_runtime_disable(dev);
 467 err_serdev_close:
 468         serdev_device_close(bdev->serdev);
 469 err_open:
 470         return err;
 471 }
 472
 473 static int btmtkuart_close(struct hci_dev *hdev)
 474 {
 475         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 476         struct device *dev = &bdev->serdev->dev;
 477
 478         /* Shutdown the clock and power domain the device requires */
 479         clk_disable_unprepare(bdev->clk);
 480         pm_runtime_put_sync(dev);
 481         pm_runtime_disable(dev);
 482
 483         serdev_device_close(bdev->serdev);
 484
 485         return 0;
 486 }
 487
 488 static int btmtkuart_flush(struct hci_dev *hdev)
 489 {
 490         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 491
 492         /* Flush any pending characters */
 493         serdev_device_write_flush(bdev->serdev);
 494         skb_queue_purge(&bdev->txq);
 495
 496         cancel_work_sync(&bdev->tx_work);
 497
 498         kfree_skb(bdev->rx_skb);
 499         bdev->rx_skb = NULL;
 500
 501         bdev->stp_cursor = 2;
 502         bdev->stp_dlen = 0;
 503
 504         return 0;
 505 }
 506
 507 static int btmtkuart_func_query(struct hci_dev *hdev)
 508 {
 509         struct btmtk_hci_wmt_params wmt_params;
 510         int status, err;
 511         u8 param = 0;
 512
 513         /* Query whether the function is enabled */
 514         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 515         wmt_params.flag = 4;
 516         wmt_params.dlen = sizeof(param);
 517         wmt_params.data = &param;
 518         wmt_params.status = &status;
 519
 520         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 521         if (err < 0) {
 522                 bt_dev_err(hdev, "Failed to query function status (%d)", err);
 523                 return err;
 524         }
 525
 526         return status;
 527 }
 528
 529 static int btmtkuart_change_baudrate(struct hci_dev *hdev)
 530 {
 531         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 532         struct btmtk_hci_wmt_params wmt_params;
 533         __le32 baudrate;
 534         u8 param;
 535         int err;
 536
 537         /* Indicate the device to enter the probe state the host is
 538          * ready to change a new baudrate.
 539          */
 540         baudrate = cpu_to_le32(bdev->desired_speed);
 541         wmt_params.op = BTMTK_WMT_HIF;
 542         wmt_params.flag = 1;
 543         wmt_params.dlen = 4;
 544         wmt_params.data = &baudrate;
 545         wmt_params.status = NULL;
 546
 547         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 548         if (err < 0) {
 549                 bt_dev_err(hdev, "Failed to device baudrate (%d)", err);
 550                 return err;
 551         }
 552
 553         err = serdev_device_set_baudrate(bdev->serdev,
 554                                          bdev->desired_speed);
 555         if (err < 0) {
 556                 bt_dev_err(hdev, "Failed to set up host baudrate (%d)",
 557                            err);
 558                 return err;
 559         }
 560
 561         serdev_device_set_flow_control(bdev->serdev, false);
 562
 563         /* Send a dummy byte 0xff to activate the new baudrate */
 564         param = 0xff;
 565         err = serdev_device_write_buf(bdev->serdev, &param, sizeof(param));
 566         if (err < 0 || err < sizeof(param))
 567                 return err;
 568
 569         serdev_device_wait_until_sent(bdev->serdev, 0);
 570
 571         /* Wait some time for the device changing baudrate done */
 572         usleep_range(20000, 22000);
 573
 574         /* Test the new baudrate */
 575         wmt_params.op = BTMTK_WMT_TEST;
 576         wmt_params.flag = 7;
 577         wmt_params.dlen = 0;
 578         wmt_params.data = NULL;
 579         wmt_params.status = NULL;
 580
 581         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 582         if (err < 0) {
 583                 bt_dev_err(hdev, "Failed to test new baudrate (%d)",
 584                            err);
 585                 return err;
 586         }
 587
 588         bdev->curr_speed = bdev->desired_speed;
 589
 590         return 0;
 591 }
 592
 593 static int btmtkuart_setup(struct hci_dev *hdev)
 594 {
 595         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 596         struct btmtk_hci_wmt_params wmt_params;
 597         ktime_t calltime, delta, rettime;
 598         struct btmtk_tci_sleep tci_sleep;
 599         unsigned long long duration;
 600         struct sk_buff *skb;
 601         int err, status;
 602         u8 param = 0x1;
 603
 604         calltime = ktime_get();
 605
 606         /* Wakeup MCUSYS is required for certain devices before we start to
 607          * do any setups.
 608          */
 609         if (test_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state)) {
 610                 wmt_params.op = BTMTK_WMT_WAKEUP;
 611                 wmt_params.flag = 3;
 612                 wmt_params.dlen = 0;
 613                 wmt_params.data = NULL;
 614                 wmt_params.status = NULL;
 615
 616                 err = mtk_hci_wmt_sync(hdev, &wmt_params);
 617                 if (err < 0) {
 618                         bt_dev_err(hdev, "Failed to wakeup the chip (%d)", err);
 619                         return err;
 620                 }
 621
 622                 clear_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
 623         }
 624
 625         if (btmtkuart_is_standalone(bdev))
 626                 btmtkuart_change_baudrate(hdev);
 627
 628         /* Query whether the firmware is already download */
 629         wmt_params.op = BTMTK_WMT_SEMAPHORE;
 630         wmt_params.flag = 1;
 631         wmt_params.dlen = 0;
 632         wmt_params.data = NULL;
 633         wmt_params.status = &status;
 634
 635         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 636         if (err < 0) {
 637                 bt_dev_err(hdev, "Failed to query firmware status (%d)", err);
 638                 return err;
 639         }
 640
 641         if (status == BTMTK_WMT_PATCH_DONE) {
 642                 bt_dev_info(hdev, "Firmware already downloaded");
 643                 goto ignore_setup_fw;
 644         }
 645
 646         /* Setup a firmware which the device definitely requires */
 647         err = btmtk_setup_firmware(hdev, bdev->data->fwname, mtk_hci_wmt_sync);
 648         if (err < 0)
 649                 return err;
 650
 651 ignore_setup_fw:
 652         /* Query whether the device is already enabled */
 653         err = readx_poll_timeout(btmtkuart_func_query, hdev, status,
 654                                  status < 0 || status != BTMTK_WMT_ON_PROGRESS,
 655                                  2000, 5000000);
 656         /* -ETIMEDOUT happens */
 657         if (err < 0)
 658                 return err;
 659
 660         /* The other errors happen in btusb_mtk_func_query */
 661         if (status < 0)
 662                 return status;
 663
 664         if (status == BTMTK_WMT_ON_DONE) {
 665                 bt_dev_info(hdev, "function already on");
 666                 goto ignore_func_on;
 667         }
 668
 669         /* Enable Bluetooth protocol */
 670         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 671         wmt_params.flag = 0;
 672         wmt_params.dlen = sizeof(param);
 673         wmt_params.data = &param;
 674         wmt_params.status = NULL;
 675
 676         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 677         if (err < 0) {
 678                 bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
 679                 return err;
 680         }
 681
 682 ignore_func_on:
 683         /* Apply the low power environment setup */
 684         tci_sleep.mode = 0x5;
 685         tci_sleep.duration = cpu_to_le16(0x640);
 686         tci_sleep.host_duration = cpu_to_le16(0x640);
 687         tci_sleep.host_wakeup_pin = 0;
 688         tci_sleep.time_compensation = 0;
 689
 690         skb = __hci_cmd_sync(hdev, 0xfc7a, sizeof(tci_sleep), &tci_sleep,
 691                              HCI_INIT_TIMEOUT);
 692         if (IS_ERR(skb)) {
 693                 err = PTR_ERR(skb);
 694                 bt_dev_err(hdev, "Failed to apply low power setting (%d)", err);
 695                 return err;
 696         }
 697         kfree_skb(skb);
 698
 699         rettime = ktime_get();
 700         delta = ktime_sub(rettime, calltime);
 701         duration = (unsigned long long)ktime_to_ns(delta) >> 10;
 702
 703         bt_dev_info(hdev, "Device setup in %llu usecs", duration);
 704
 705         return 0;
 706 }
 707
 708 static int btmtkuart_shutdown(struct hci_dev *hdev)
 709 {
 710         struct btmtk_hci_wmt_params wmt_params;
 711         u8 param = 0x0;
 712         int err;
 713
 714         /* Disable the device */
 715         wmt_params.op = BTMTK_WMT_FUNC_CTRL;
 716         wmt_params.flag = 0;
 717         wmt_params.dlen = sizeof(param);
 718         wmt_params.data = &param;
 719         wmt_params.status = NULL;
 720
 721         err = mtk_hci_wmt_sync(hdev, &wmt_params);
 722         if (err < 0) {
 723                 bt_dev_err(hdev, "Failed to send wmt func ctrl (%d)", err);
 724                 return err;
 725         }
 726
 727         return 0;
 728 }
 729
 730 static int btmtkuart_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 731 {
 732         struct btmtkuart_dev *bdev = hci_get_drvdata(hdev);
 733         struct mtk_stp_hdr *shdr;
 734         int err, dlen, type = 0;
 735
 736         /* Prepend skb with frame type */
 737         memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 738
 739         /* Make sure that there is enough rooms for STP header and trailer */
 740         if (unlikely(skb_headroom(skb) < sizeof(*shdr)) ||
 741             (skb_tailroom(skb) < MTK_STP_TLR_SIZE)) {
 742                 err = pskb_expand_head(skb, sizeof(*shdr), MTK_STP_TLR_SIZE,
 743                                        GFP_ATOMIC);
 744                 if (err < 0)
 745                         return err;
 746         }
 747
 748         /* Add the STP header */
 749         dlen = skb->len;
 750         shdr = skb_push(skb, sizeof(*shdr));
 751         shdr->prefix = 0x80;
 752         shdr->dlen = cpu_to_be16((dlen & 0x0fff) | (type << 12));
 753         shdr->cs = 0;           /* MT7622 doesn't care about checksum value */
 754
 755         /* Add the STP trailer */
 756         skb_put_zero(skb, MTK_STP_TLR_SIZE);
 757
 758         skb_queue_tail(&bdev->txq, skb);
 759
 760         btmtkuart_tx_wakeup(bdev);
 761         return 0;
 762 }
 763
 764 static int btmtkuart_parse_dt(struct serdev_device *serdev)
 765 {
 766         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 767         struct device_node *node = serdev->dev.of_node;
 768         u32 speed = 921600;
 769         int err;
 770
 771         if (btmtkuart_is_standalone(bdev)) {
 772                 of_property_read_u32(node, "current-speed", &speed);
 773
 774                 bdev->desired_speed = speed;
 775
 776                 bdev->vcc = devm_regulator_get(&serdev->dev, "vcc");
 777                 if (IS_ERR(bdev->vcc)) {
 778                         err = PTR_ERR(bdev->vcc);
 779                         return err;
 780                 }
 781
 782                 bdev->osc = devm_clk_get_optional(&serdev->dev, "osc");
 783                 if (IS_ERR(bdev->osc)) {
 784                         err = PTR_ERR(bdev->osc);
 785                         return err;
 786                 }
 787
 788                 bdev->boot = devm_gpiod_get_optional(&serdev->dev, "boot",
 789                                                      GPIOD_OUT_LOW);
 790                 if (IS_ERR(bdev->boot)) {
 791                         err = PTR_ERR(bdev->boot);
 792                         return err;
 793                 }
 794
 795                 bdev->pinctrl = devm_pinctrl_get(&serdev->dev);
 796                 if (IS_ERR(bdev->pinctrl)) {
 797                         err = PTR_ERR(bdev->pinctrl);
 798                         return err;
 799                 }
 800
 801                 bdev->pins_boot = pinctrl_lookup_state(bdev->pinctrl,
 802                                                        "default");
 803                 if (IS_ERR(bdev->pins_boot) && !bdev->boot) {
 804                         err = PTR_ERR(bdev->pins_boot);
 805                         dev_err(&serdev->dev,
 806                                 "Should assign RXD to LOW at boot stage\n");
 807                         return err;
 808                 }
 809
 810                 bdev->pins_runtime = pinctrl_lookup_state(bdev->pinctrl,
 811                                                           "runtime");
 812                 if (IS_ERR(bdev->pins_runtime)) {
 813                         err = PTR_ERR(bdev->pins_runtime);
 814                         return err;
 815                 }
 816
 817                 bdev->reset = devm_gpiod_get_optional(&serdev->dev, "reset",
 818                                                       GPIOD_OUT_LOW);
 819                 if (IS_ERR(bdev->reset)) {
 820                         err = PTR_ERR(bdev->reset);
 821                         return err;
 822                 }
 823         } else if (btmtkuart_is_builtin_soc(bdev)) {
 824                 bdev->clk = devm_clk_get(&serdev->dev, "ref");
 825                 if (IS_ERR(bdev->clk))
 826                         return PTR_ERR(bdev->clk);
 827         }
 828
 829         return 0;
 830 }
 831
 832 static int btmtkuart_probe(struct serdev_device *serdev)
 833 {
 834         struct btmtkuart_dev *bdev;
 835         struct hci_dev *hdev;
 836         int err;
 837
 838         bdev = devm_kzalloc(&serdev->dev, sizeof(*bdev), GFP_KERNEL);
 839         if (!bdev)
 840                 return -ENOMEM;
 841
 842         bdev->data = of_device_get_match_data(&serdev->dev);
 843         if (!bdev->data)
 844                 return -ENODEV;
 845
 846         bdev->serdev = serdev;
 847         serdev_device_set_drvdata(serdev, bdev);
 848
 849         serdev_device_set_client_ops(serdev, &btmtkuart_client_ops);
 850
 851         err = btmtkuart_parse_dt(serdev);
 852         if (err < 0)
 853                 return err;
 854
 855         INIT_WORK(&bdev->tx_work, btmtkuart_tx_work);
 856         skb_queue_head_init(&bdev->txq);
 857
 858         /* Initialize and register HCI device */
 859         hdev = hci_alloc_dev();
 860         if (!hdev) {
 861                 dev_err(&serdev->dev, "Can't allocate HCI device\n");
 862                 return -ENOMEM;
 863         }
 864
 865         bdev->hdev = hdev;
 866
 867         hdev->bus = HCI_UART;
 868         hci_set_drvdata(hdev, bdev);
 869
 870         hdev->open     = btmtkuart_open;
 871         hdev->close    = btmtkuart_close;
 872         hdev->flush    = btmtkuart_flush;
 873         hdev->setup    = btmtkuart_setup;
 874         hdev->shutdown = btmtkuart_shutdown;
 875         hdev->send     = btmtkuart_send_frame;
 876         hdev->set_bdaddr = btmtk_set_bdaddr;
 877         SET_HCIDEV_DEV(hdev, &serdev->dev);
 878
 879         hdev->manufacturer = 70;
 880         set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
 881
 882         if (btmtkuart_is_standalone(bdev)) {
 883                 err = clk_prepare_enable(bdev->osc);
 884                 if (err < 0)
 885                         goto err_hci_free_dev;
 886
 887                 if (bdev->boot) {
 888                         gpiod_set_value_cansleep(bdev->boot, 1);
 889                 } else {
 890                         /* Switch to the specific pin state for the booting
 891                          * requires.
 892                          */
 893                         pinctrl_select_state(bdev->pinctrl, bdev->pins_boot);
 894                 }
 895
 896                 /* Power on */
 897                 err = regulator_enable(bdev->vcc);
 898                 if (err < 0)
 899                         goto err_clk_disable_unprepare;
 900
 901                 /* Reset if the reset-gpios is available otherwise the board
 902                  * -level design should be guaranteed.
 903                  */
 904                 if (bdev->reset) {
 905                         gpiod_set_value_cansleep(bdev->reset, 1);
 906                         usleep_range(1000, 2000);
 907                         gpiod_set_value_cansleep(bdev->reset, 0);
 908                 }
 909
 910                 /* Wait some time until device got ready and switch to the pin
 911                  * mode the device requires for UART transfers.
 912                  */
 913                 msleep(50);
 914
 915                 if (bdev->boot)
 916                         devm_gpiod_put(&serdev->dev, bdev->boot);
 917
 918                 pinctrl_select_state(bdev->pinctrl, bdev->pins_runtime);
 919
 920                 /* A standalone device doesn't depends on power domain on SoC,
 921                  * so mark it as no callbacks.
 922                  */
 923                 pm_runtime_no_callbacks(&serdev->dev);
 924
 925                 set_bit(BTMTKUART_REQUIRED_WAKEUP, &bdev->tx_state);
 926         }
 927
 928         err = hci_register_dev(hdev);
 929         if (err < 0) {
 930                 dev_err(&serdev->dev, "Can't register HCI device\n");
 931                 goto err_regulator_disable;
 932         }
 933
 934         return 0;
 935
 936 err_regulator_disable:
 937         if (btmtkuart_is_standalone(bdev))
 938                 regulator_disable(bdev->vcc);
 939 err_clk_disable_unprepare:
 940         if (btmtkuart_is_standalone(bdev))
 941                 clk_disable_unprepare(bdev->osc);
 942 err_hci_free_dev:
 943         hci_free_dev(hdev);
 944
 945         return err;
 946 }
 947
 948 static void btmtkuart_remove(struct serdev_device *serdev)
 949 {
 950         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
 951         struct hci_dev *hdev = bdev->hdev;
 952
 953         if (btmtkuart_is_standalone(bdev)) {
 954                 regulator_disable(bdev->vcc);
 955                 clk_disable_unprepare(bdev->osc);
 956         }
 957
 958         hci_unregister_dev(hdev);
 959         hci_free_dev(hdev);
 960 }
 961
 962 static const struct btmtkuart_data mt7622_data = {
 963         .fwname = FIRMWARE_MT7622,
 964 };
 965
 966 static const struct btmtkuart_data mt7663_data = {
 967         .flags = BTMTKUART_FLAG_STANDALONE_HW,
 968         .fwname = FIRMWARE_MT7663,
 969 };
 970
 971 static const struct btmtkuart_data mt7668_data = {
 972         .flags = BTMTKUART_FLAG_STANDALONE_HW,
 973         .fwname = FIRMWARE_MT7668,
 974 };
 975
 976 #ifdef CONFIG_OF
 977 static const struct of_device_id mtk_of_match_table[] = {
 978         { .compatible = "mediatek,mt7622-bluetooth", .data = &mt7622_data},
 979         { .compatible = "mediatek,mt7663u-bluetooth", .data = &mt7663_data},
 980         { .compatible = "mediatek,mt7668u-bluetooth", .data = &mt7668_data},
 981         { }
 982 };
 983 MODULE_DEVICE_TABLE(of, mtk_of_match_table);
 984 #endif
 985
 986 static struct serdev_device_driver btmtkuart_driver = {
 987         .probe = btmtkuart_probe,
 988         .remove = btmtkuart_remove,
 989         .driver = {
 990                 .name = "btmtkuart",
 991                 .of_match_table = of_match_ptr(mtk_of_match_table),
 992         },
 993 };
 994
 995 module_serdev_device_driver(btmtkuart_driver);
 996
 997 MODULE_AUTHOR("Sean Wang <sean.wang@mediatek.com>");
 998 MODULE_DESCRIPTION("MediaTek Bluetooth Serial driver ver " VERSION);
 999 MODULE_VERSION(VERSION);
1000 MODULE_LICENSE("GPL");