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, const u8 *ptr,
 131                          size_t count)
 132 {
 133         int len = 0;
 134         unsigned char *plen;
 135
 136         pr_debug("%s", __func__);
 137         /* Decode received bytes here */
 138         while (count) {
 139                 if (kim_gdata->rx_count) {
 140                         len = min_t(unsigned int, kim_gdata->rx_count, count);
 141                         skb_put_data(kim_gdata->rx_skb, ptr, len);
 142                         kim_gdata->rx_count -= len;
 143                         count -= len;
 144                         ptr += len;
 145
 146                         if (kim_gdata->rx_count)
 147                                 continue;
 148
 149                         /* Check ST RX state machine , where are we? */
 150                         switch (kim_gdata->rx_state) {
 151                                 /* Waiting for complete packet ? */
 152                         case ST_W4_DATA:
 153                                 pr_debug("Complete pkt received");
 154                                 validate_firmware_response(kim_gdata);
 155                                 kim_gdata->rx_state = ST_W4_PACKET_TYPE;
 156                                 kim_gdata->rx_skb = NULL;
 157                                 continue;
 158                                 /* Waiting for Bluetooth event header ? */
 159                         case ST_W4_HEADER:
 160                                 plen =
 161                                 (unsigned char *)&kim_gdata->rx_skb->data[1];
 162                                 pr_debug("event hdr: plen 0x%02x\n", *plen);
 163                                 kim_check_data_len(kim_gdata, *plen);
 164                                 continue;
 165                         }       /* end of switch */
 166                 }               /* end of if rx_state */
 167                 switch (*ptr) {
 168                         /* Bluetooth event packet? */
 169                 case 0x04:
 170                         kim_gdata->rx_state = ST_W4_HEADER;
 171                         kim_gdata->rx_count = 2;
 172                         break;
 173                 default:
 174                         pr_info("unknown packet");
 175                         ptr++;
 176                         count--;
 177                         continue;
 178                 }
 179                 ptr++;
 180                 count--;
 181                 kim_gdata->rx_skb =
 182                         alloc_skb(1024+8, GFP_ATOMIC);
 183                 if (!kim_gdata->rx_skb) {
 184                         pr_err("can't allocate mem for new packet");
 185                         kim_gdata->rx_state = ST_W4_PACKET_TYPE;
 186                         kim_gdata->rx_count = 0;
 187                         return;
 188                 }
 189                 skb_reserve(kim_gdata->rx_skb, 8);
 190                 kim_gdata->rx_skb->cb[0] = 4;
 191                 kim_gdata->rx_skb->cb[1] = 0;
 192
 193         }
 194         return;
 195 }
 196
 197 static long read_local_version(struct kim_data_s *kim_gdata, char *bts_scr_name)
 198 {
 199         unsigned short version = 0, chip = 0, min_ver = 0, maj_ver = 0;
 200         static const char read_ver_cmd[] = { 0x01, 0x01, 0x10, 0x00 };
 201         long time_left;
 202
 203         pr_debug("%s", __func__);
 204
 205         reinit_completion(&kim_gdata->kim_rcvd);
 206         if (4 != st_int_write(kim_gdata->core_data, read_ver_cmd, 4)) {
 207                 pr_err("kim: couldn't write 4 bytes");
 208                 return -EIO;
 209         }
 210
 211         time_left = wait_for_completion_interruptible_timeout(
 212                 &kim_gdata->kim_rcvd, msecs_to_jiffies(CMD_RESP_TIME));
 213         if (time_left <= 0) {
 214                 pr_err(" waiting for ver info- timed out or received signal");
 215                 return time_left ? -ERESTARTSYS : -ETIMEDOUT;
 216         }
 217         reinit_completion(&kim_gdata->kim_rcvd);
 218         /*
 219          * the positions 12 & 13 in the response buffer provide with the
 220          * chip, major & minor numbers
 221          */
 222
 223         version =
 224                 MAKEWORD(kim_gdata->resp_buffer[12],
 225                                 kim_gdata->resp_buffer[13]);
 226         chip = (version & 0x7C00) >> 10;
 227         min_ver = (version & 0x007F);
 228         maj_ver = (version & 0x0380) >> 7;
 229
 230         if (version & 0x8000)
 231                 maj_ver |= 0x0008;
 232
 233         sprintf(bts_scr_name, "ti-connectivity/TIInit_%d.%d.%d.bts",
 234                 chip, maj_ver, min_ver);
 235
 236         /* to be accessed later via sysfs entry */
 237         kim_gdata->version.full = version;
 238         kim_gdata->version.chip = chip;
 239         kim_gdata->version.maj_ver = maj_ver;
 240         kim_gdata->version.min_ver = min_ver;
 241
 242         pr_info("%s", bts_scr_name);
 243         return 0;
 244 }
 245
 246 static void skip_change_remote_baud(unsigned char **ptr, long *len)
 247 {
 248         unsigned char *nxt_action, *cur_action;
 249         cur_action = *ptr;
 250
 251         nxt_action = cur_action + sizeof(struct bts_action) +
 252                 ((struct bts_action *) cur_action)->size;
 253
 254         if (((struct bts_action *) nxt_action)->type != ACTION_WAIT_EVENT) {
 255                 pr_err("invalid action after change remote baud command");
 256         } else {
 257                 *ptr = *ptr + sizeof(struct bts_action) +
 258                         ((struct bts_action *)cur_action)->size;
 259                 *len = *len - (sizeof(struct bts_action) +
 260                                 ((struct bts_action *)cur_action)->size);
 261                 /* warn user on not commenting these in firmware */
 262                 pr_warn("skipping the wait event of change remote baud");
 263         }
 264 }
 265
 266 /*
 267  * download_firmware -
 268  *      internal function which parses through the .bts firmware
 269  *      script file intreprets SEND, DELAY actions only as of now
 270  */
 271 static long download_firmware(struct kim_data_s *kim_gdata)
 272 {
 273         long err = 0;
 274         long len = 0;
 275         unsigned char *ptr = NULL;
 276         unsigned char *action_ptr = NULL;
 277         unsigned char bts_scr_name[40] = { 0 }; /* 40 char long bts scr name? */
 278         int wr_room_space;
 279         int cmd_size;
 280         unsigned long timeout;
 281
 282         err = read_local_version(kim_gdata, bts_scr_name);
 283         if (err != 0) {
 284                 pr_err("kim: failed to read local ver");
 285                 return err;
 286         }
 287         err =
 288             request_firmware(&kim_gdata->fw_entry, bts_scr_name,
 289                              &kim_gdata->kim_pdev->dev);
 290         if (unlikely((err != 0) || (kim_gdata->fw_entry->data == NULL) ||
 291                      (kim_gdata->fw_entry->size == 0))) {
 292                 pr_err(" request_firmware failed(errno %ld) for %s", err,
 293                            bts_scr_name);
 294                 return -EINVAL;
 295         }
 296         ptr = (void *)kim_gdata->fw_entry->data;
 297         len = kim_gdata->fw_entry->size;
 298         /*
 299          * bts_header to remove out magic number and
 300          * version
 301          */
 302         ptr += sizeof(struct bts_header);
 303         len -= sizeof(struct bts_header);
 304
 305         while (len > 0 && ptr) {
 306                 pr_debug(" action size %d, type %d ",
 307                            ((struct bts_action *)ptr)->size,
 308                            ((struct bts_action *)ptr)->type);
 309
 310                 switch (((struct bts_action *)ptr)->type) {
 311                 case ACTION_SEND_COMMAND:       /* action send */
 312                         pr_debug("S");
 313                         action_ptr = &(((struct bts_action *)ptr)->data[0]);
 314                         if (unlikely
 315                             (((struct hci_command *)action_ptr)->opcode ==
 316                              0xFF36)) {
 317                                 /*
 318                                  * ignore remote change
 319                                  * baud rate HCI VS command
 320                                  */
 321                                 pr_warn("change remote baud"
 322                                     " rate command in firmware");
 323                                 skip_change_remote_baud(&ptr, &len);
 324                                 break;
 325                         }
 326                         /*
 327                          * Make sure we have enough free space in uart
 328                          * tx buffer to write current firmware command
 329                          */
 330                         cmd_size = ((struct bts_action *)ptr)->size;
 331                         timeout = jiffies + msecs_to_jiffies(CMD_WR_TIME);
 332                         do {
 333                                 wr_room_space =
 334                                         st_get_uart_wr_room(kim_gdata->core_data);
 335                                 if (wr_room_space < 0) {
 336                                         pr_err("Unable to get free "
 337                                                         "space info from uart tx buffer");
 338                                         release_firmware(kim_gdata->fw_entry);
 339                                         return wr_room_space;
 340                                 }
 341                                 mdelay(1); /* wait 1ms before checking room */
 342                         } while ((wr_room_space < cmd_size) &&
 343                                         time_before(jiffies, timeout));
 344
 345                         /* Timeout happened ? */
 346                         if (time_after_eq(jiffies, timeout)) {
 347                                 pr_err("Timeout while waiting for free "
 348                                                 "free space in uart tx buffer");
 349                                 release_firmware(kim_gdata->fw_entry);
 350                                 return -ETIMEDOUT;
 351                         }
 352                         /*
 353                          * reinit completion before sending for the
 354                          * relevant wait
 355                          */
 356                         reinit_completion(&kim_gdata->kim_rcvd);
 357
 358                         /*
 359                          * Free space found in uart buffer, call st_int_write
 360                          * to send current firmware command to the uart tx
 361                          * buffer.
 362                          */
 363                         err = st_int_write(kim_gdata->core_data,
 364                         ((struct bts_action_send *)action_ptr)->data,
 365                                            ((struct bts_action *)ptr)->size);
 366                         if (unlikely(err < 0)) {
 367                                 release_firmware(kim_gdata->fw_entry);
 368                                 return err;
 369                         }
 370                         /*
 371                          * Check number of bytes written to the uart tx buffer
 372                          * and requested command write size
 373                          */
 374                         if (err != cmd_size) {
 375                                 pr_err("Number of bytes written to uart "
 376                                                 "tx buffer are not matching with "
 377                                                 "requested cmd write size");
 378                                 release_firmware(kim_gdata->fw_entry);
 379                                 return -EIO;
 380                         }
 381                         break;
 382                 case ACTION_WAIT_EVENT:  /* wait */
 383                         pr_debug("W");
 384                         err = wait_for_completion_interruptible_timeout(
 385                                         &kim_gdata->kim_rcvd,
 386                                         msecs_to_jiffies(CMD_RESP_TIME));
 387                         if (err <= 0) {
 388                                 pr_err("response timeout/signaled during fw download ");
 389                                 /* timed out */
 390                                 release_firmware(kim_gdata->fw_entry);
 391                                 return err ? -ERESTARTSYS : -ETIMEDOUT;
 392                         }
 393                         reinit_completion(&kim_gdata->kim_rcvd);
 394                         break;
 395                 case ACTION_DELAY:      /* sleep */
 396                         pr_info("sleep command in scr");
 397                         action_ptr = &(((struct bts_action *)ptr)->data[0]);
 398                         mdelay(((struct bts_action_delay *)action_ptr)->msec);
 399                         break;
 400                 }
 401                 len =
 402                     len - (sizeof(struct bts_action) +
 403                            ((struct bts_action *)ptr)->size);
 404                 ptr =
 405                     ptr + sizeof(struct bts_action) +
 406                     ((struct bts_action *)ptr)->size;
 407         }
 408         /* fw download complete */
 409         release_firmware(kim_gdata->fw_entry);
 410         return 0;
 411 }
 412
 413 /**********************************************************************/
 414 /* functions called from ST core */
 415 /* called from ST Core, when REG_IN_PROGRESS (registration in progress)
 416  * can be because of
 417  * 1. response to read local version
 418  * 2. during send/recv's of firmware download
 419  */
 420 void st_kim_recv(void *disc_data, const u8 *data, size_t count)
 421 {
 422         struct st_data_s        *st_gdata = (struct st_data_s *)disc_data;
 423         struct kim_data_s       *kim_gdata = st_gdata->kim_data;
 424
 425         /*
 426          * proceed to gather all data and distinguish read fw version response
 427          * from other fw responses when data gathering is complete
 428          */
 429         kim_int_recv(kim_gdata, data, count);
 430         return;
 431 }
 432
 433 /*
 434  * to signal completion of line discipline installation
 435  * called from ST Core, upon tty_open
 436  */
 437 void st_kim_complete(void *kim_data)
 438 {
 439         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 440         complete(&kim_gdata->ldisc_installed);
 441 }
 442
 443 /*
 444  * st_kim_start - called from ST Core upon 1st registration
 445  *      This involves toggling the chip enable gpio, reading
 446  *      the firmware version from chip, forming the fw file name
 447  *      based on the chip version, requesting the fw, parsing it
 448  *      and perform download(send/recv).
 449  */
 450 long st_kim_start(void *kim_data)
 451 {
 452         long err = 0;
 453         long retry = POR_RETRY_COUNT;
 454         struct ti_st_plat_data  *pdata;
 455         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 456
 457         pr_info(" %s", __func__);
 458         pdata = kim_gdata->kim_pdev->dev.platform_data;
 459
 460         do {
 461                 /* platform specific enabling code here */
 462                 if (pdata->chip_enable)
 463                         pdata->chip_enable(kim_gdata);
 464
 465                 /* Configure BT nShutdown to HIGH state */
 466                 gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 467                 mdelay(5);      /* FIXME: a proper toggle */
 468                 gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
 469                 mdelay(100);
 470                 /* re-initialize the completion */
 471                 reinit_completion(&kim_gdata->ldisc_installed);
 472                 /* send notification to UIM */
 473                 kim_gdata->ldisc_install = 1;
 474                 pr_info("ldisc_install = 1");
 475                 sysfs_notify(&kim_gdata->kim_pdev->dev.kobj,
 476                                 NULL, "install");
 477                 /* wait for ldisc to be installed */
 478                 err = wait_for_completion_interruptible_timeout(
 479                         &kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
 480                 if (!err) {
 481                         /*
 482                          * ldisc installation timeout,
 483                          * flush uart, power cycle BT_EN
 484                          */
 485                         pr_err("ldisc installation timeout");
 486                         err = st_kim_stop(kim_gdata);
 487                         continue;
 488                 } else {
 489                         /* ldisc installed now */
 490                         pr_info("line discipline installed");
 491                         err = download_firmware(kim_gdata);
 492                         if (err != 0) {
 493                                 /*
 494                                  * ldisc installed but fw download failed,
 495                                  * flush uart & power cycle BT_EN
 496                                  */
 497                                 pr_err("download firmware failed");
 498                                 err = st_kim_stop(kim_gdata);
 499                                 continue;
 500                         } else {        /* on success don't retry */
 501                                 break;
 502                         }
 503                 }
 504         } while (retry--);
 505         return err;
 506 }
 507
 508 /*
 509  * st_kim_stop - stop communication with chip.
 510  *      This can be called from ST Core/KIM, on the-
 511  *      (a) last un-register when chip need not be powered there-after,
 512  *      (b) upon failure to either install ldisc or download firmware.
 513  *      The function is responsible to (a) notify UIM about un-installation,
 514  *      (b) flush UART if the ldisc was installed.
 515  *      (c) reset BT_EN - pull down nshutdown at the end.
 516  *      (d) invoke platform's chip disabling routine.
 517  */
 518 long st_kim_stop(void *kim_data)
 519 {
 520         long err = 0;
 521         struct kim_data_s       *kim_gdata = (struct kim_data_s *)kim_data;
 522         struct ti_st_plat_data  *pdata =
 523                 kim_gdata->kim_pdev->dev.platform_data;
 524         struct tty_struct       *tty = kim_gdata->core_data->tty;
 525
 526         reinit_completion(&kim_gdata->ldisc_installed);
 527
 528         if (tty) {      /* can be called before ldisc is installed */
 529                 /* Flush any pending characters in the driver and discipline. */
 530                 tty_ldisc_flush(tty);
 531                 tty_driver_flush_buffer(tty);
 532         }
 533
 534         /* send uninstall notification to UIM */
 535         pr_info("ldisc_install = 0");
 536         kim_gdata->ldisc_install = 0;
 537         sysfs_notify(&kim_gdata->kim_pdev->dev.kobj, NULL, "install");
 538
 539         /* wait for ldisc to be un-installed */
 540         err = wait_for_completion_interruptible_timeout(
 541                 &kim_gdata->ldisc_installed, msecs_to_jiffies(LDISC_TIME));
 542         if (!err) {             /* timeout */
 543                 pr_err(" timed out waiting for ldisc to be un-installed");
 544                 err = -ETIMEDOUT;
 545         }
 546
 547         /* By default configure BT nShutdown to LOW state */
 548         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 549         mdelay(1);
 550         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_HIGH);
 551         mdelay(1);
 552         gpio_set_value_cansleep(kim_gdata->nshutdown, GPIO_LOW);
 553
 554         /* platform specific disable */
 555         if (pdata->chip_disable)
 556                 pdata->chip_disable(kim_gdata);
 557         return err;
 558 }
 559
 560 /**********************************************************************/
 561 /* functions called from subsystems */
 562 /* called when debugfs entry is read from */
 563
 564 static int version_show(struct seq_file *s, void *unused)
 565 {
 566         struct kim_data_s *kim_gdata = s->private;
 567         seq_printf(s, "%04X %d.%d.%d\n", kim_gdata->version.full,
 568                         kim_gdata->version.chip, kim_gdata->version.maj_ver,
 569                         kim_gdata->version.min_ver);
 570         return 0;
 571 }
 572
 573 static int list_show(struct seq_file *s, void *unused)
 574 {
 575         struct kim_data_s *kim_gdata = s->private;
 576         kim_st_list_protocols(kim_gdata->core_data, s);
 577         return 0;
 578 }
 579
 580 static ssize_t show_install(struct device *dev,
 581                 struct device_attribute *attr, char *buf)
 582 {
 583         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 584         return sprintf(buf, "%d\n", kim_data->ldisc_install);
 585 }
 586
 587 #ifdef DEBUG
 588 static ssize_t store_dev_name(struct device *dev,
 589                 struct device_attribute *attr, const char *buf, size_t count)
 590 {
 591         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 592         pr_debug("storing dev name >%s<", buf);
 593         strscpy(kim_data->dev_name, buf, sizeof(kim_data->dev_name));
 594         pr_debug("stored dev name >%s<", kim_data->dev_name);
 595         return count;
 596 }
 597
 598 static ssize_t store_baud_rate(struct device *dev,
 599                 struct device_attribute *attr, const char *buf, size_t count)
 600 {
 601         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 602         pr_debug("storing baud rate >%s<", buf);
 603         sscanf(buf, "%ld", &kim_data->baud_rate);
 604         pr_debug("stored baud rate >%ld<", kim_data->baud_rate);
 605         return count;
 606 }
 607 #endif  /* if DEBUG */
 608
 609 static ssize_t show_dev_name(struct device *dev,
 610                 struct device_attribute *attr, char *buf)
 611 {
 612         struct kim_data_s *kim_data = dev_get_drvdata(dev);
 613         return sprintf(buf, "%s\n", kim_data->dev_name);
 614 }
 615
 616 static ssize_t show_baud_rate(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, "%d\n", kim_data->baud_rate);
 621 }
 622
 623 static ssize_t show_flow_cntrl(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->flow_cntrl);
 628 }
 629
 630 /* structures specific for sysfs entries */
 631 static struct kobj_attribute ldisc_install =
 632 __ATTR(install, 0444, (void *)show_install, NULL);
 633
 634 static struct kobj_attribute uart_dev_name =
 635 #ifdef DEBUG    /* TODO: move this to debug-fs if possible */
 636 __ATTR(dev_name, 0644, (void *)show_dev_name, (void *)store_dev_name);
 637 #else
 638 __ATTR(dev_name, 0444, (void *)show_dev_name, NULL);
 639 #endif
 640
 641 static struct kobj_attribute uart_baud_rate =
 642 #ifdef DEBUG    /* TODO: move to debugfs */
 643 __ATTR(baud_rate, 0644, (void *)show_baud_rate, (void *)store_baud_rate);
 644 #else
 645 __ATTR(baud_rate, 0444, (void *)show_baud_rate, NULL);
 646 #endif
 647
 648 static struct kobj_attribute uart_flow_cntrl =
 649 __ATTR(flow_cntrl, 0444, (void *)show_flow_cntrl, NULL);
 650
 651 static struct attribute *uim_attrs[] = {
 652         &ldisc_install.attr,
 653         &uart_dev_name.attr,
 654         &uart_baud_rate.attr,
 655         &uart_flow_cntrl.attr,
 656         NULL,
 657 };
 658
 659 static const struct attribute_group uim_attr_grp = {
 660         .attrs = uim_attrs,
 661 };
 662
 663 /*
 664  * st_kim_ref - reference the core's data
 665  *      This references the per-ST platform device in the arch/xx/
 666  *      board-xx.c file.
 667  *      This would enable multiple such platform devices to exist
 668  *      on a given platform
 669  */
 670 void st_kim_ref(struct st_data_s **core_data, int id)
 671 {
 672         struct platform_device  *pdev;
 673         struct kim_data_s       *kim_gdata;
 674         /* get kim_gdata reference from platform device */
 675         pdev = st_get_plat_device(id);
 676         if (!pdev)
 677                 goto err;
 678         kim_gdata = platform_get_drvdata(pdev);
 679         if (!kim_gdata)
 680                 goto err;
 681
 682         *core_data = kim_gdata->core_data;
 683         return;
 684 err:
 685         *core_data = NULL;
 686 }
 687
 688 DEFINE_SHOW_ATTRIBUTE(version);
 689 DEFINE_SHOW_ATTRIBUTE(list);
 690
 691 /**********************************************************************/
 692 /* functions called from platform device driver subsystem
 693  * need to have a relevant platform device entry in the platform's
 694  * board-*.c file
 695  */
 696
 697 static struct dentry *kim_debugfs_dir;
 698 static int kim_probe(struct platform_device *pdev)
 699 {
 700         struct kim_data_s       *kim_gdata;
 701         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 702         int err;
 703
 704         if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
 705                 /* multiple devices could exist */
 706                 st_kim_devices[pdev->id] = pdev;
 707         } else {
 708                 /* platform's sure about existence of 1 device */
 709                 st_kim_devices[0] = pdev;
 710         }
 711
 712         kim_gdata = kzalloc(sizeof(struct kim_data_s), GFP_KERNEL);
 713         if (!kim_gdata) {
 714                 pr_err("no mem to allocate");
 715                 return -ENOMEM;
 716         }
 717         platform_set_drvdata(pdev, kim_gdata);
 718
 719         err = st_core_init(&kim_gdata->core_data);
 720         if (err != 0) {
 721                 pr_err(" ST core init failed");
 722                 err = -EIO;
 723                 goto err_core_init;
 724         }
 725         /* refer to itself */
 726         kim_gdata->core_data->kim_data = kim_gdata;
 727
 728         /* Claim the chip enable nShutdown gpio from the system */
 729         kim_gdata->nshutdown = pdata->nshutdown_gpio;
 730         err = gpio_request(kim_gdata->nshutdown, "kim");
 731         if (unlikely(err)) {
 732                 pr_err(" gpio %d request failed ", kim_gdata->nshutdown);
 733                 goto err_sysfs_group;
 734         }
 735
 736         /* Configure nShutdown GPIO as output=0 */
 737         err = gpio_direction_output(kim_gdata->nshutdown, 0);
 738         if (unlikely(err)) {
 739                 pr_err(" unable to configure gpio %d", kim_gdata->nshutdown);
 740                 goto err_sysfs_group;
 741         }
 742         /* get reference of pdev for request_firmware */
 743         kim_gdata->kim_pdev = pdev;
 744         init_completion(&kim_gdata->kim_rcvd);
 745         init_completion(&kim_gdata->ldisc_installed);
 746
 747         err = sysfs_create_group(&pdev->dev.kobj, &uim_attr_grp);
 748         if (err) {
 749                 pr_err("failed to create sysfs entries");
 750                 goto err_sysfs_group;
 751         }
 752
 753         /* copying platform data */
 754         strscpy(kim_gdata->dev_name, pdata->dev_name,
 755                 sizeof(kim_gdata->dev_name));
 756         kim_gdata->flow_cntrl = pdata->flow_cntrl;
 757         kim_gdata->baud_rate = pdata->baud_rate;
 758         pr_info("sysfs entries created\n");
 759
 760         kim_debugfs_dir = debugfs_create_dir("ti-st", NULL);
 761
 762         debugfs_create_file("version", S_IRUGO, kim_debugfs_dir,
 763                                 kim_gdata, &version_fops);
 764         debugfs_create_file("protocols", S_IRUGO, kim_debugfs_dir,
 765                                 kim_gdata, &list_fops);
 766         return 0;
 767
 768 err_sysfs_group:
 769         st_core_exit(kim_gdata->core_data);
 770
 771 err_core_init:
 772         kfree(kim_gdata);
 773
 774         return err;
 775 }
 776
 777 static void kim_remove(struct platform_device *pdev)
 778 {
 779         /* free the GPIOs requested */
 780         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 781         struct kim_data_s       *kim_gdata;
 782
 783         kim_gdata = platform_get_drvdata(pdev);
 784
 785         /*
 786          * Free the Bluetooth/FM/GPIO
 787          * nShutdown gpio from the system
 788          */
 789         gpio_free(pdata->nshutdown_gpio);
 790         pr_info("nshutdown GPIO Freed");
 791
 792         debugfs_remove_recursive(kim_debugfs_dir);
 793         sysfs_remove_group(&pdev->dev.kobj, &uim_attr_grp);
 794         pr_info("sysfs entries removed");
 795
 796         kim_gdata->kim_pdev = NULL;
 797         st_core_exit(kim_gdata->core_data);
 798
 799         kfree(kim_gdata);
 800         kim_gdata = NULL;
 801 }
 802
 803 static int kim_suspend(struct platform_device *pdev, pm_message_t state)
 804 {
 805         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 806
 807         if (pdata->suspend)
 808                 return pdata->suspend(pdev, state);
 809
 810         return 0;
 811 }
 812
 813 static int kim_resume(struct platform_device *pdev)
 814 {
 815         struct ti_st_plat_data  *pdata = pdev->dev.platform_data;
 816
 817         if (pdata->resume)
 818                 return pdata->resume(pdev);
 819
 820         return 0;
 821 }
 822
 823 /**********************************************************************/
 824 /* entry point for ST KIM module, called in from ST Core */
 825 static struct platform_driver kim_platform_driver = {
 826         .probe = kim_probe,
 827         .remove_new = kim_remove,
 828         .suspend = kim_suspend,
 829         .resume = kim_resume,
 830         .driver = {
 831                 .name = "kim",
 832         },
 833 };
 834
 835 module_platform_driver(kim_platform_driver);
 836
 837 MODULE_AUTHOR("Pavan Savoy <pavan_savoy@ti.com>");
 838 MODULE_DESCRIPTION("Shared Transport Driver for TI BT/FM/GPS combo chips ");
 839 MODULE_LICENSE("GPL");