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