drivers/misc/ti-st/st_kim.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Shared Transport Line discipline driver Core
   4  *      Init Manager module responsible for GPIO control
   5  *      and firmware download
   6  *  Copyright (C) 2009-2010 Texas Instruments
   7  *  Author: Pavan Savoy <pavan_savoy@ti.com>
   8  */
   9
  10 #define pr_fmt(fmt) "(stk) :" fmt
  11 #include <linux/platform_device.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/firmware.h>
  14 #include <linux/delay.h>
  15 #include <linux/wait.h>
  16 #include <linux/gpio.h>
  17 #include <linux/debugfs.h>
  18 #include <linux/seq_file.h>
  19 #include <linux/sched.h>
  20 #include <linux/sysfs.h>
  21 #include <linux/tty.h>
  22
  23 #include <linux/skbuff.h>
  24 #include <linux/ti_wilink_st.h>
  25 #include <linux/module.h>
  26
  27 #define MAX_ST_DEVICES  3       /* Imagine 1 on each UART for now */
  28 static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
  29
  30 /**********************************************************************/
  31 /* internal functions */
  32
  33 /*
  34  * st_get_plat_device -
  35  *      function which returns the reference to the platform device
  36  *      requested by id. As of now only 1 such device exists (id=0)
  37  *      the context requesting for reference can get the id to be
  38  *      requested by a. The protocol driver which is registering or
  39  *      b. the tty device which is opened.
  40  */
  41 static struct platform_device *st_get_plat_device(int id)
  42 {
  43         return st_kim_devices[id];
  44 }
  45
  46 /*
  47  * validate_firmware_response -
  48  *      function to return whether the firmware response was proper
  49  *      in case of error don't complete so that waiting for proper
  50  *      response times out
  51  */
  52 static void validate_firmware_response(struct kim_data_s *kim_gdata)
  53 {
  54         struct sk_buff *skb = kim_gdata->rx_skb;
  55         if (!skb)
  56                 return;
  57
  58         /*
  59          * these magic numbers are the position in the response buffer which
  60          * allows us to distinguish whether the response is for the read
  61          * version info. command
  62          */
  63         if (skb->data[2] == 0x01 && skb->data[3] == 0x01 &&
  64                         skb->data[4] == 0x10 && skb->data[5] == 0x00) {
  65                 /* fw version response */
  66                 memcpy(kim_gdata->resp_buffer,
  67                                 kim_gdata->rx_skb->data,
  68                                 kim_gdata->rx_skb->len);
  69                 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
  70                 kim_gdata->rx_skb = NULL;
  71                 kim_gdata->rx_count = 0;
  72         } else if (unlikely(skb->data[5] != 0)) {
  73                 pr_err("no proper response during fw download");
  74                 pr_err("data6 %x", skb->data[5]);
  75                 kfree_skb(skb);
  76                 return;         /* keep waiting for the proper response */
  77         }
  78         /* becos of all the script being downloaded */
  79         complete_all(&kim_gdata->kim_rcvd);
  80         kfree_skb(skb);
  81 }
  82
  83 /*
  84  * check for data len received inside kim_int_recv
  85  * most often hit the last case to update state to waiting for data
  86  */
  87 static inline int kim_check_data_len(struct kim_data_s *kim_gdata, int len)
  88 {
  89         register int room = skb_tailroom(kim_gdata->rx_skb);
  90
  91         pr_debug("len %d room %d", len, room);
  92
  93         if (!len) {
  94                 validate_firmware_response(kim_gdata);
  95         } else if (len > room) {
  96                 /*
  97                  * Received packet's payload length is larger.
  98                  * We can't accommodate it in created skb.
  99                  */
 100                 pr_err("Data length is too large len %d room %d", len,
 101                            room);
 102                 kfree_skb(kim_gdata->rx_skb);
 103         } else {
 104                 /*
 105                  * Packet header has non-zero payload length and
 106                  * we have enough space in created skb. Lets read
 107                  * payload data */
 108                 kim_gdata->rx_state = ST_W4_DATA;
 109                 kim_gdata->rx_count = len;
 110                 return len;
 111         }
 112
 113         /*
 114          * Change ST LL state to continue to process next
 115          * packet
 116          */
 117         kim_gdata->rx_state = ST_W4_PACKET_TYPE;
 118         kim_gdata->rx_skb = NULL;
 119         kim_gdata->rx_count = 0;
 120
 121         return 0;
 122 }
 123
 124 /*
 125  * kim_int_recv - receive function called during firmware download
 126  *      firmware download responses on different UART drivers
 127  *      have been observed to come in bursts of different
 128  *      tty_receive and hence the logic
 129  */
 130 static void kim_int_recv(struct kim_data_s *kim_gdata,
 131         const unsigned char *data, long count)
 132 {
 133         const unsigned char *ptr;
 134         int len = 0;
 135         unsigned char *plen;
 136
 137         pr_debug("%s", __func__);
 138         /* Decode received bytes here */
 139         ptr = data;
 140         if (unlikely(ptr == NULL)) {
 141                 pr_err(" received null from TTY ");
 142                 return;
 143         }
 144
 145         while (count) {
 146                 if (kim_gdata->rx_count) {
 147                         len = min_t(unsigned int, kim_gdata->rx_count, count);
 148                         skb_put_data(kim_gdata->rx_skb, ptr, len);
 149                         kim_gdata->rx_count -= len;
 150                         count -= len;
 151                         ptr += len;
 152
 153                         if (kim_gdata->rx_count)
 154                                 continue;
 155
 156                         /* Check ST RX state machine , where are we? */
 157                         switch (kim_gdata->rx_state) {
 158                                 /* Waiting for complete packet ? */
 159                         case ST_W4_DATA:
 160                                 pr_debug("Complete pkt received");
 161                                 validate_firmware_response(kim_gdata);
 162                                 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
 163                                 kim_gdata->rx_skb = NULL;
 164                                 continue;
 165                                 /* Waiting for Bluetooth event header ? */
 166                         case ST_W4_HEADER:
 167                                 plen =
 168                                 (unsigned char *)&kim_gdata->rx_skb->data[1];
 169                                 pr_debug("event hdr: plen 0x%02x\n", *plen);
 170                                 kim_check_data_len(kim_gdata, *plen);
 171                                 continue;
 172                         }       /* end of switch */
 173                 }               /* end of if rx_state */
 174                 switch (*ptr) {
 175                         /* Bluetooth event packet? */
 176                 case 0x04:
 177                         kim_gdata->rx_state = ST_W4_HEADER;
 178                         kim_gdata->rx_count = 2;
 179                         break;
 180                 default:
 181                         pr_info("unknown packet");
 182                         ptr++;
 183                         count--;
 184                         continue;
 185                 }
 186                 ptr++;
 187                 count--;
 188                 kim_gdata->rx_skb =
 189                         alloc_skb(1024+8, GFP_ATOMIC);
 190                 if (!kim_gdata->rx_skb) {
 191                         pr_err("can't allocate mem for new packet");
 192                         kim_gdata->rx_state = ST_W4_PACKET_TYPE;
 193                         kim_gdata->rx_count = 0;
 194                         return;
 195                 }
 196                 skb_reserve(kim_gdata->rx_skb, 8);
 197                 kim_gdata->rx_skb->cb[0] = 4;
 198                 kim_gdata->rx_skb->cb[1] = 0;
 199
 200         }
 201         return;
 202 }
 203
 204 static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
 205 {
 206         unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
 207         static const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
 208         long timeout;
 209
 210         pr_debug("%s", __func__);
 211
 212         reinit_completion(&kim_gdata->kim_rcvd);
 213         if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
 214                 pr_err("kim: couldn't write 4 bytes");
 215                 return -EIO;
 216         }
 217
 218         timeout = wait_for_completion_interruptible_timeout(
 219                 &kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME));
 220         if (timeout <= 0) {
 221                 pr_err(" waiting for ver info- timed out or received signal");
 222                 return timeout ? -ERESTARTSYS : -ETIMEDOUT;
 223         }
 224         reinit_completion(&kim_gdata->kim_rcvd);
 225         /*
 226          * the positions 12 & 13 in the response buffer provide with the
 227          * chip, major & minor numbers
 228          */
 229
 230         version =
 231                 MAKEWORD(kim_gdata->resp_buffer[12],
 232                                 kim_gdata->resp_buffer[13]);
 233         chip = (version & 0x7C00) >> 10;
 234         min_ver = (version & 0x007F);
 235         maj_ver = (version & 0x0380) >> 7;
 236
 237         if (version & 0x8000)
 238                 maj_ver |= 0x0008;
 239
 240         sprintf(bts_scr_name, "/*(DEBLOBBED)*/",
 241                 chip, maj_ver, min_ver);
 242
 243         /* to be accessed later via sysfs entry */
 244         kim_gdata->version.full = version;
 245         kim_gdata->version.chip = chip;
 246         kim_gdata->version.maj_ver = maj_ver;
 247         kim_gdata->version.min_ver = min_ver;
 248
 249         pr_info("%s", bts_scr_name);
 250         return 0;
 251 }
 252
 253 static void skip_change_remote_baud(unsigned char **ptr, long *len)
 254 {
 255         unsigned char *nxt_action, *cur_action;
 256         cur_action = *ptr;
 257
 258         nxt_action = cur_action + sizeof(struct bts_action) +
 259                 ((struct bts_action *) cur_action)->size;
 260
 261         if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
 262                 pr_err("invalid action after change remote baud command");
 263         } else {
 264                 *ptr = *ptr + sizeof(struct bts_action) +
 265                         ((struct bts_action *)cur_action)->size;
 266                 *len = *len - (sizeof(struct bts_action) +
 267                                 ((struct bts_action *)cur_action)->size);
 268                 /* warn user on not commenting these in firmware */
 269                 pr_warn("skipping the wait event of change remote baud");
 270         }
 271 }
 272
 273 /*
 274  * download_firmware -
 275  *      internal function which parses through the .bts firmware
 276  *      script file intreprets SEND, DELAY actions only as of now
 277  */
 278 static long download_firmware(struct kim_data_s *kim_gdata)
 279 {
 280         long err = 0;
 281         long len = 0;
 282         unsigned char *ptr = NULL;
 283         unsigned char *action_ptr = NULL;
 284         unsigned char bts_scr_name[40] = { 0 }; /* 40 char long bts scr name? */
 285         int wr_room_space;
 286         int cmd_size;
 287         unsigned long timeout;
 288
 289         err = read_local_version(kim_gdata, bts_scr_name);
 290         if (err != 0) {
 291                 pr_err("kim: failed to read local ver");
 292                 return err;
 293         }
 294         err =
 295             reject_firmware(&kim_gdata->fw_entry, bts_scr_name,
 296                              &kim_gdata->kim_pdev->dev);
 297         if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
 298                      (kim_gdata->fw_entry->size == 0))) {
 299                 pr_err(" request_firmware failed(errno %ld) for %s", err,
 300                            bts_scr_name);
 301                 return -EINVAL;
 302         }
 303         ptr = (void *)kim_gdata->fw_entry->data;
 304         len = kim_gdata->fw_entry->size;
 305         /*
 306          * bts_header to remove out magic number and
 307          * version
 308          */
 309         ptr += sizeof(struct bts_header);
 310         len -= sizeof(struct bts_header);
 311
 312         while (len > 0 && ptr) {
 313                 pr_debug(" action size %d, type %d ",
 314                            ((struct bts_action *)ptr)->size,
 315                            ((struct bts_action *)ptr)->type);
 316
 317                 switch (((struct bts_action *)ptr)->type) {
 318                 case ACTION_SEND_COMMAND:       /* action send */
 319                         pr_debug("S");
 320                         action_ptr = &(((struct bts_action *)ptr)->data[0]);
 321                         if (unlikely
 322                             (((struct hci_command *)action_ptr)->opcode ==
 323                              0xFF36)) {
 324                                 /*
 325                                  * ignore remote change
 326                                  * baud rate HCI VS command
 327                                  */
 328                                 pr_warn("change remote baud"
 329                                     " rate command in firmware");
 330                                 skip_change_remote_baud(&ptr, &len);
 331                                 break;
 332                         }
 333                         /*
 334                          * Make sure we have enough free space in uart
 335                          * tx buffer to write current firmware command
 336                          */
 337                         cmd_size = ((struct bts_action *)ptr)->size;
 338                         timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
 339                         do {
 340                                 wr_room_space =
 341                                         st_get_uart_wr_room(kim_gdata->core_data);
 342                                 if (wr_room_space < 0) {
 343                                         pr_err("Unable to get free "
 344                                                         "space info from uart tx buffer");
 345                                         release_firmware(kim_gdata->fw_entry);
 346                                         return wr_room_space;
 347                                 }
 348                                 mdelay(1); /* wait 1ms before checking room */
 349                         } while ((wr_room_space < cmd_size) &&
 350                                         time_before(jiffies, timeout));
 351
 352                         /* Timeout happened ? */
 353                         if (time_after_eq(jiffies, timeout)) {
 354                                 pr_err("Timeout while waiting for free "
 355                                                 "free space in uart tx buffer");
 356                                 release_firmware(kim_gdata->fw_entry);
 357                                 return -ETIMEDOUT;
 358                         }
 359                         /*
 360                          * reinit completion before sending for the
 361                          * relevant wait
 362                          */
 363                         reinit_completion(&kim_gdata->kim_rcvd);
 364
 365                         /*
 366                          * Free space found in uart buffer, call st_int_write
 367                          * to send current firmware command to the uart tx
 368                          * buffer.
 369                          */
 370                         err = st_int_write(kim_gdata->core_data,
 371                         ((struct bts_action_send *)action_ptr)->data,
 372                                            ((struct bts_action *)ptr)->size);
 373                         if (unlikely(err < 0)) {
 374                                 release_firmware(kim_gdata->fw_entry);
 375                                 return err;
 376                         }
 377                         /*
 378                          * Check number of bytes written to the uart tx buffer
 379                          * and requested command write size
 380                          */
 381                         if (err != cmd_size) {
 382                                 pr_err("Number of bytes written to uart "
 383                                                 "tx buffer are not matching with "
 384                                                 "requested cmd write size");
 385                                 release_firmware(kim_gdata->fw_entry);
 386                                 return -EIO;
 387                         }
 388                         break;
 389                 case ACTION_WAIT_EVENT:  /* wait */
 390                         pr_debug("W");
 391                         err = wait_for_completion_interruptible_timeout(
 392                                         &kim_gdata->kim_rcvd,
 393                                         msecs_to_jiffies(CMD_RESP_TIME));
 394                         if (err <= 0) {
 395                                 pr_err("response timeout/signaled during fw download ");
 396                                 /* timed out */
 397                                 release_firmware(kim_gdata->fw_entry);
 398                                 return err ? -ERESTARTSYS : -ETIMEDOUT;
 399                         }
 400                         reinit_completion(&kim_gdata->kim_rcvd);
 401                         break;
 402                 case ACTION_DELAY:      /* sleep */
 403                         pr_info("sleep command in scr");
 404                         action_ptr = &(((struct bts_action *)ptr)->data[0]);
 405                         mdelay(((struct bts_action_delay *)action_ptr)->msec);
 406                         break;
 407                 }
 408                 len =
 409                     len - (sizeof(struct bts_action) +
 410                            ((struct bts_action *)ptr)->size);
 411                 ptr =
 412                     ptr + sizeof(struct bts_action) +
 413                     ((struct bts_action *)ptr)->size;
 414         }
 415         /* fw download complete */
 416         release_firmware(kim_gdata->fw_entry);
 417         return 0;
 418 }
 419
 420 /**********************************************************************/
 421 /* functions called from ST core */
 422 /* called from ST Core, when REG_IN_PROGRESS (registration in progress)
 423  * can be because of
 424  * 1. response to read local version
 425  * 2. during send/recv's of firmware download
 426  */
 427 void st_kim_recv(void *disc_data, const unsigned char *data, long count)
 428 {
 429         struct st_data_s        *st_gdata = (struct st_data_s *)disc_data;
 430         struct kim_data_s       *kim_gdata = st_gdata->kim_data;
 431
 432         /*
 433          * proceed to gather all data and distinguish read fw version response
 434          * from other fw responses when data gathering is complete
 435          */
 436         kim_int_recv(kim_gdata, data, count);
 437         return;
 438 }
 439
 440 /*
 441  * to signal completion of line discipline installation
 442  * called from ST Core, upon tty_open
 443  */
 444 void st_kim_complete(void *kim_data)
 445 {
 446         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 447         complete(&kim_gdata->ldisc_installed);
 448 }
 449
 450 /*
 451  * st_kim_start - called from ST Core upon 1st registration
 452  *      This involves toggling the chip enable gpio, reading
 453  *      the firmware version from chip, forming the fw file name
 454  *      based on the chip version, requesting the fw, parsing it
 455  *      and perform download(send/recv).
 456  */
 457 long st_kim_start(void *kim_data)
 458 {
 459         long err = 0;
 460         long retry = POR_RETRY_COUNT;
 461         struct ti_st_plat_data  *pdata;
 462         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 463
 464         pr_info(" %s", __func__);
 465         pdata = kim_gdata->kim_pdev->dev.platform_data;
 466
 467         do {
 468                 /* platform specific enabling code here */
 469                 if (pdata->chip_enable)
 470                         pdata->chip_enable(kim_gdata);
 471
 472                 /* Configure BT nShutdown to HIGH state */
 473                 gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 474                 mdelay(5);      /* FIXME: a proper toggle */
 475                 gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
 476                 mdelay(100);
 477                 /* re-initialize the completion */
 478                 reinit_completion(&kim_gdata->ldisc_installed);
 479                 /* send notification to UIM */
 480                 kim_gdata->ldisc_install = 1;
 481                 pr_info("ldisc_install = 1");
 482                 sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
 483                                 NULL, "install");
 484                 /* wait for ldisc to be installed */
 485                 err = wait_for_completion_interruptible_timeout(
 486                         &kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
 487                 if (!err) {
 488                         /*
 489                          * ldisc installation timeout,
 490                          * flush uart, power cycle BT_EN
 491                          */
 492                         pr_err("ldisc installation timeout");
 493                         err = st_kim_stop(kim_gdata);
 494                         continue;
 495                 } else {
 496                         /* ldisc installed now */
 497                         pr_info("line discipline installed");
 498                         err = download_firmware(kim_gdata);
 499                         if (err != 0) {
 500                                 /*
 501                                  * ldisc installed but fw download failed,
 502                                  * flush uart & power cycle BT_EN
 503                                  */
 504                                 pr_err("download firmware failed");
 505                                 err = st_kim_stop(kim_gdata);
 506                                 continue;
 507                         } else {        /* on success don't retry */
 508                                 break;
 509                         }
 510                 }
 511         } while (retry--);
 512         return err;
 513 }
 514
 515 /*
 516  * st_kim_stop - stop communication with chip.
 517  *      This can be called from ST Core/KIM, on the-
 518  *      (a) last un-register when chip need not be powered there-after,
 519  *      (b) upon failure to either install ldisc or download firmware.
 520  *      The function is responsible to (a) notify UIM about un-installation,
 521  *      (b) flush UART if the ldisc was installed.
 522  *      (c) reset BT_EN - pull down nshutdown at the end.
 523  *      (d) invoke platform's chip disabling routine.
 524  */
 525 long st_kim_stop(void *kim_data)
 526 {
 527         long err = 0;
 528         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 529         struct ti_st_plat_data  *pdata =
 530                 kim_gdata->kim_pdev->dev.platform_data;
 531         struct tty_struct       *tty = kim_gdata->core_data->tty;
 532
 533         reinit_completion(&kim_gdata->ldisc_installed);
 534
 535         if (tty) {      /* can be called before ldisc is installed */
 536                 /* Flush any pending characters in the driver and discipline. */
 537                 tty_ldisc_flush(tty);
 538                 tty_driver_flush_buffer(tty);
 539         }
 540
 541         /* send uninstall notification to UIM */
 542         pr_info("ldisc_install = 0");
 543         kim_gdata->ldisc_install = 0;
 544         sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");
 545
 546         /* wait for ldisc to be un-installed */
 547         err = wait_for_completion_interruptible_timeout(
 548                 &kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
 549         if (!err) {             /* timeout */
 550                 pr_err(" timed out waiting for ldisc to be un-installed");
 551                 err = -ETIMEDOUT;
 552         }
 553
 554         /* By default configure BT nShutdown to LOW state */
 555         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 556         mdelay(1);
 557         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
 558         mdelay(1);
 559         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 560
 561         /* platform specific disable */
 562         if (pdata->chip_disable)
 563                 pdata->chip_disable(kim_gdata);
 564         return err;
 565 }
 566
 567 /**********************************************************************/
 568 /* functions called from subsystems */
 569 /* called when debugfs entry is read from */
 570
 571 static int version_show(struct seq_file *s, void *unused)
 572 {
 573         struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
 574         seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
 575                         kim_gdata->version.chip, kim_gdata->version.maj_ver,
 576                         kim_gdata->version.min_ver);
 577         return 0;
 578 }
 579
 580 static int list_show(struct seq_file *s, void *unused)
 581 {
 582         struct kim_data_s *kim_gdata = (struct kim_data_s *)s->private;
 583         kim_st_list_protocols(kim_gdata->core_data, s);
 584         return 0;
 585 }
 586
 587 static ssize_t show_install(struct device *dev,
 588                 struct device_attribute *attr, char *buf)
 589 {
 590         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 591         return sprintf(buf, "%d\n", kim_data->ldisc_install);
 592 }
 593
 594 #ifdef DEBUG
 595 static ssize_t store_dev_name(struct device *dev,
 596                 struct device_attribute *attr, const char *buf, size_t count)
 597 {
 598         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 599         pr_debug("storing dev name >%s<", buf);
 600         strncpy(kim_data->dev_name, buf, count);
 601         pr_debug("stored dev name >%s<", kim_data->dev_name);
 602         return count;
 603 }
 604
 605 static ssize_t store_baud_rate(struct device *dev,
 606                 struct device_attribute *attr, const char *buf, size_t count)
 607 {
 608         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 609         pr_debug("storing baud rate >%s<", buf);
 610         sscanf(buf, "%ld", &kim_data->baud_rate);
 611         pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
 612         return count;
 613 }
 614 #endif  /* if DEBUG */
 615
 616 static ssize_t show_dev_name(struct device *dev,
 617                 struct device_attribute *attr, char *buf)
 618 {
 619         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 620         return sprintf(buf, "%s\n", kim_data->dev_name);
 621 }
 622
 623 static ssize_t show_baud_rate(struct device *dev,
 624                 struct device_attribute *attr, char *buf)
 625 {
 626         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 627         return sprintf(buf, "%d\n", kim_data->baud_rate);
 628 }
 629
 630 static ssize_t show_flow_cntrl(struct device *dev,
 631                 struct device_attribute *attr, char *buf)
 632 {
 633         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 634         return sprintf(buf, "%d\n", kim_data->flow_cntrl);
 635 }
 636
 637 /* structures specific for sysfs entries */
 638 static struct kobj_attribute ldisc_install =
 639 __ATTR(install, 0444, (void *)show_install, NULL);
 640
 641 static struct kobj_attribute uart_dev_name =
 642 #ifdef DEBUG    /* TODO: move this to debug-fs if possible */
 643 __ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
 644 #else
 645 __ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
 646 #endif
 647
 648 static struct kobj_attribute uart_baud_rate =
 649 #ifdef DEBUG    /* TODO: move to debugfs */
 650 __ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
 651 #else
 652 __ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
 653 #endif
 654
 655 static struct kobj_attribute uart_flow_cntrl =
 656 __ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
 657
 658 static struct attribute *uim_attrs[] = {
 659         &ldisc_install.attr,
 660         &uart_dev_name.attr,
 661         &uart_baud_rate.attr,
 662         &uart_flow_cntrl.attr,
 663         NULL,
 664 };
 665
 666 static const struct attribute_group uim_attr_grp = {
 667         .attrs = uim_attrs,
 668 };
 669
 670 /*
 671  * st_kim_ref - reference the core's data
 672  *      This references the per-ST platform device in the arch/xx/
 673  *      board-xx.c file.
 674  *      This would enable multiple such platform devices to exist
 675  *      on a given platform
 676  */
 677 void st_kim_ref(struct st_data_s **core_data, int id)
 678 {
 679         struct platform_device  *pdev;
 680         struct kim_data_s       *kim_gdata;
 681         /* get kim_gdata reference from platform device */
 682         pdev = st_get_plat_device(id);
 683         if (!pdev)
 684                 goto err;
 685         kim_gdata = platform_get_drvdata(pdev);
 686         if (!kim_gdata)
 687                 goto err;
 688
 689         *core_data = kim_gdata->core_data;
 690         return;
 691 err:
 692         *core_data = NULL;
 693 }
 694
 695 DEFINE_SHOW_ATTRIBUTE(version);
 696 DEFINE_SHOW_ATTRIBUTE(list);
 697
 698 /**********************************************************************/
 699 /* functions called from platform device driver subsystem
 700  * need to have a relevant platform device entry in the platform's
 701  * board-*.c file
 702  */
 703
 704 static struct dentry *kim_debugfs_dir;
 705 static int kim_probe(struct platform_device *pdev)
 706 {
 707         struct kim_data_s       *kim_gdata;
 708         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 709         int err;
 710
 711         if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
 712                 /* multiple devices could exist */
 713                 st_kim_devices[pdev->id] = pdev;
 714         } else {
 715                 /* platform's sure about existence of 1 device */
 716                 st_kim_devices[0] = pdev;
 717         }
 718
 719         kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_KERNEL);
 720         if (!kim_gdata) {
 721                 pr_err("no mem to allocate");
 722                 return -ENOMEM;
 723         }
 724         platform_set_drvdata(pdev, kim_gdata);
 725
 726         err = st_core_init(&kim_gdata->core_data);
 727         if (err != 0) {
 728                 pr_err(" ST core init failed");
 729                 err = -EIO;
 730                 goto err_core_init;
 731         }
 732         /* refer to itself */
 733         kim_gdata->core_data->kim_data = kim_gdata;
 734
 735         /* Claim the chip enable nShutdown gpio from the system */
 736         kim_gdata->nshutdown = pdata->nshutdown_gpio;
 737         err = gpio_request(kim_gdata->nshutdown, "kim");
 738         if (unlikely(err)) {
 739                 pr_err(" gpio %d request failed ", kim_gdata->nshutdown);
 740                 goto err_sysfs_group;
 741         }
 742
 743         /* Configure nShutdown GPIO as output=0 */
 744         err = gpio_direction_output(kim_gdata->nshutdown, 0);
 745         if (unlikely(err)) {
 746                 pr_err(" unable to configure gpio %d", kim_gdata->nshutdown);
 747                 goto err_sysfs_group;
 748         }
 749         /* get reference of pdev for request_firmware */
 750         kim_gdata->kim_pdev = pdev;
 751         init_completion(&kim_gdata->kim_rcvd);
 752         init_completion(&kim_gdata->ldisc_installed);
 753
 754         err = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
 755         if (err) {
 756                 pr_err("failed to create sysfs entries");
 757                 goto err_sysfs_group;
 758         }
 759
 760         /* copying platform data */
 761         strncpy(kim_gdata->dev_name, pdata->dev_name, UART_DEV_NAME_LEN);
 762         kim_gdata->flow_cntrl = pdata->flow_cntrl;
 763         kim_gdata->baud_rate = pdata->baud_rate;
 764         pr_info("sysfs entries created\n");
 765
 766         kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
 767
 768         debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
 769                                 kim_gdata, &version_fops);
 770         debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
 771                                 kim_gdata, &list_fops);
 772         return 0;
 773
 774 err_sysfs_group:
 775         st_core_exit(kim_gdata->core_data);
 776
 777 err_core_init:
 778         kfree(kim_gdata);
 779
 780         return err;
 781 }
 782
 783 static int kim_remove(struct platform_device *pdev)
 784 {
 785         /* free the GPIOs requested */
 786         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 787         struct kim_data_s       *kim_gdata;
 788
 789         kim_gdata = platform_get_drvdata(pdev);
 790
 791         /*
 792          * Free the Bluetooth/FM/GPIO
 793          * nShutdown gpio from the system
 794          */
 795         gpio_free(pdata->nshutdown_gpio);
 796         pr_info("nshutdown GPIO Freed");
 797
 798         debugfs_remove_recursive(kim_debugfs_dir);
 799         sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
 800         pr_info("sysfs entries removed");
 801
 802         kim_gdata->kim_pdev = NULL;
 803         st_core_exit(kim_gdata->core_data);
 804
 805         kfree(kim_gdata);
 806         kim_gdata = NULL;
 807         return 0;
 808 }
 809
 810 static int kim_suspend(struct platform_device *pdev, pm_message_t state)
 811 {
 812         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 813
 814         if (pdata->suspend)
 815                 return pdata->suspend(pdev, state);
 816
 817         return 0;
 818 }
 819
 820 static int kim_resume(struct platform_device *pdev)
 821 {
 822         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 823
 824         if (pdata->resume)
 825                 return pdata->resume(pdev);
 826
 827         return 0;
 828 }
 829
 830 /**********************************************************************/
 831 /* entry point for ST KIM module, called in from ST Core */
 832 static struct platform_driver kim_platform_driver = {
 833         .probe = kim_probe,
 834         .remove = kim_remove,
 835         .suspend = kim_suspend,
 836         .resume = kim_resume,
 837         .driver = {
 838                 .name = "kim",
 839         },
 840 };
 841
 842 module_platform_driver(kim_platform_driver);
 843
 844 MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
 845 MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
 846 MODULE_LICENSE("GPL");