drivers/media/radio/si470x/radio-si470x-usb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  drivers/media/radio/si470x/radio-si470x-usb.c
   4  *
   5  *  USB driver for radios with Silicon Labs Si470x FM Radio Receivers
   6  *
   7  *  Copyright (c) 2009 Tobias Lorenz <tobias.lorenz@gmx.net>
   8  */
   9
  10
  11 /*
  12  * ToDo:
  13  * - add firmware download/update support
  14  */
  15
  16
  17 /* driver definitions */
  18 #define DRIVER_AUTHOR "Tobias Lorenz <tobias.lorenz@gmx.net>"
  19 #define DRIVER_CARD "Silicon Labs Si470x FM Radio Receiver"
  20 #define DRIVER_DESC "USB radio driver for Si470x FM Radio Receivers"
  21 #define DRIVER_VERSION "1.0.10"
  22
  23 /* kernel includes */
  24 #include <linux/usb.h>
  25 #include <linux/hid.h>
  26 #include <linux/slab.h>
  27
  28 #include "radio-si470x.h"
  29
  30
  31 /* USB Device ID List */
  32 static const struct usb_device_id si470x_usb_driver_id_table[] = {
  33         /* Silicon Labs USB FM Radio Reference Design */
  34         { USB_DEVICE_AND_INTERFACE_INFO(0x10c4, 0x818a, USB_CLASS_HID, 0, 0) },
  35         /* ADS/Tech FM Radio Receiver (formerly Instant FM Music) */
  36         { USB_DEVICE_AND_INTERFACE_INFO(0x06e1, 0xa155, USB_CLASS_HID, 0, 0) },
  37         /* KWorld USB FM Radio SnapMusic Mobile 700 (FM700) */
  38         { USB_DEVICE_AND_INTERFACE_INFO(0x1b80, 0xd700, USB_CLASS_HID, 0, 0) },
  39         /* Sanei Electric, Inc. FM USB Radio (sold as DealExtreme.com PCear) */
  40         { USB_DEVICE_AND_INTERFACE_INFO(0x10c5, 0x819a, USB_CLASS_HID, 0, 0) },
  41         /* Axentia ALERT FM USB Receiver */
  42         { USB_DEVICE_AND_INTERFACE_INFO(0x12cf, 0x7111, USB_CLASS_HID, 0, 0) },
  43         /* Terminating entry */
  44         { }
  45 };
  46 MODULE_DEVICE_TABLE(usb, si470x_usb_driver_id_table);
  47
  48
  49
  50 /**************************************************************************
  51  * Module Parameters
  52  **************************************************************************/
  53
  54 /* Radio Nr */
  55 static int radio_nr = -1;
  56 module_param(radio_nr, int, 0444);
  57 MODULE_PARM_DESC(radio_nr, "Radio Nr");
  58
  59 /* USB timeout */
  60 static unsigned int usb_timeout = 500;
  61 module_param(usb_timeout, uint, 0644);
  62 MODULE_PARM_DESC(usb_timeout, "USB timeout (ms): *500*");
  63
  64 /* RDS buffer blocks */
  65 static unsigned int rds_buf = 100;
  66 module_param(rds_buf, uint, 0444);
  67 MODULE_PARM_DESC(rds_buf, "RDS buffer entries: *100*");
  68
  69 /* RDS maximum block errors */
  70 static unsigned short max_rds_errors = 1;
  71 /* 0 means   0  errors requiring correction */
  72 /* 1 means 1-2  errors requiring correction (used by original USBRadio.exe) */
  73 /* 2 means 3-5  errors requiring correction */
  74 /* 3 means   6+ errors or errors in checkword, correction not possible */
  75 module_param(max_rds_errors, ushort, 0644);
  76 MODULE_PARM_DESC(max_rds_errors, "RDS maximum block errors: *1*");
  77
  78
  79
  80 /**************************************************************************
  81  * USB HID Reports
  82  **************************************************************************/
  83
  84 /* Reports 1-16 give direct read/write access to the 16 Si470x registers */
  85 /* with the (REPORT_ID - 1) corresponding to the register address across USB */
  86 /* endpoint 0 using GET_REPORT and SET_REPORT */
  87 #define REGISTER_REPORT_SIZE    (RADIO_REGISTER_SIZE + 1)
  88 #define REGISTER_REPORT(reg)    ((reg) + 1)
  89
  90 /* Report 17 gives direct read/write access to the entire Si470x register */
  91 /* map across endpoint 0 using GET_REPORT and SET_REPORT */
  92 #define ENTIRE_REPORT_SIZE      (RADIO_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
  93 #define ENTIRE_REPORT           17
  94
  95 /* Report 18 is used to send the lowest 6 Si470x registers up the HID */
  96 /* interrupt endpoint 1 to Windows every 20 milliseconds for status */
  97 #define RDS_REPORT_SIZE         (RDS_REGISTER_NUM * RADIO_REGISTER_SIZE + 1)
  98 #define RDS_REPORT              18
  99
 100 /* Report 19: LED state */
 101 #define LED_REPORT_SIZE         3
 102 #define LED_REPORT              19
 103
 104 /* Report 19: stream */
 105 #define STREAM_REPORT_SIZE      3
 106 #define STREAM_REPORT           19
 107
 108 /* Report 20: scratch */
 109 #define SCRATCH_PAGE_SIZE       63
 110 #define SCRATCH_REPORT_SIZE     (SCRATCH_PAGE_SIZE + 1)
 111 #define SCRATCH_REPORT          20
 112
 113 /* Reports 19-22: flash upgrade of the C8051F321 */
 114 #define WRITE_REPORT_SIZE       4
 115 #define WRITE_REPORT            19
 116 #define FLASH_REPORT_SIZE       64
 117 #define FLASH_REPORT            20
 118 #define CRC_REPORT_SIZE         3
 119 #define CRC_REPORT              21
 120 #define RESPONSE_REPORT_SIZE    2
 121 #define RESPONSE_REPORT         22
 122
 123 /* Report 23: currently unused, but can accept 60 byte reports on the HID */
 124 /* interrupt out endpoint 2 every 1 millisecond */
 125 #define UNUSED_REPORT           23
 126
 127 #define MAX_REPORT_SIZE         64
 128
 129
 130
 131 /**************************************************************************
 132  * Software/Hardware Versions from Scratch Page
 133  **************************************************************************/
 134 #define RADIO_HW_VERSION                        1
 135
 136
 137
 138 /**************************************************************************
 139  * LED State Definitions
 140  **************************************************************************/
 141 #define LED_COMMAND             0x35
 142
 143 #define NO_CHANGE_LED           0x00
 144 #define ALL_COLOR_LED           0x01    /* streaming state */
 145 #define BLINK_GREEN_LED         0x02    /* connect state */
 146 #define BLINK_RED_LED           0x04
 147 #define BLINK_ORANGE_LED        0x10    /* disconnect state */
 148 #define SOLID_GREEN_LED         0x20    /* tuning/seeking state */
 149 #define SOLID_RED_LED           0x40    /* bootload state */
 150 #define SOLID_ORANGE_LED        0x80
 151
 152
 153
 154 /**************************************************************************
 155  * Stream State Definitions
 156  **************************************************************************/
 157 #define STREAM_COMMAND  0x36
 158 #define STREAM_VIDPID   0x00
 159 #define STREAM_AUDIO    0xff
 160
 161
 162
 163 /**************************************************************************
 164  * Bootloader / Flash Commands
 165  **************************************************************************/
 166
 167 /* unique id sent to bootloader and required to put into a bootload state */
 168 #define UNIQUE_BL_ID            0x34
 169
 170 /* mask for the flash data */
 171 #define FLASH_DATA_MASK         0x55
 172
 173 /* bootloader commands */
 174 #define GET_SW_VERSION_COMMAND  0x00
 175 #define SET_PAGE_COMMAND        0x01
 176 #define ERASE_PAGE_COMMAND      0x02
 177 #define WRITE_PAGE_COMMAND      0x03
 178 #define CRC_ON_PAGE_COMMAND     0x04
 179 #define READ_FLASH_BYTE_COMMAND 0x05
 180 #define RESET_DEVICE_COMMAND    0x06
 181 #define GET_HW_VERSION_COMMAND  0x07
 182 #define BLANK                   0xff
 183
 184 /* bootloader command responses */
 185 #define COMMAND_OK              0x01
 186 #define COMMAND_FAILED          0x02
 187 #define COMMAND_PENDING         0x03
 188
 189
 190
 191 /**************************************************************************
 192  * General Driver Functions - REGISTER_REPORTs
 193  **************************************************************************/
 194
 195 /*
 196  * si470x_get_report - receive a HID report
 197  */
 198 static int si470x_get_report(struct si470x_device *radio, void *buf, int size)
 199 {
 200         unsigned char *report = buf;
 201         int retval;
 202
 203         retval = usb_control_msg(radio->usbdev,
 204                 usb_rcvctrlpipe(radio->usbdev, 0),
 205                 HID_REQ_GET_REPORT,
 206                 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
 207                 report[0], 2,
 208                 buf, size, usb_timeout);
 209
 210         if (retval < 0)
 211                 dev_warn(&radio->intf->dev,
 212                         "si470x_get_report: usb_control_msg returned %d\n",
 213                         retval);
 214         return retval;
 215 }
 216
 217
 218 /*
 219  * si470x_set_report - send a HID report
 220  */
 221 static int si470x_set_report(struct si470x_device *radio, void *buf, int size)
 222 {
 223         unsigned char *report = buf;
 224         int retval;
 225
 226         retval = usb_control_msg(radio->usbdev,
 227                 usb_sndctrlpipe(radio->usbdev, 0),
 228                 HID_REQ_SET_REPORT,
 229                 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
 230                 report[0], 2,
 231                 buf, size, usb_timeout);
 232
 233         if (retval < 0)
 234                 dev_warn(&radio->intf->dev,
 235                         "si470x_set_report: usb_control_msg returned %d\n",
 236                         retval);
 237         return retval;
 238 }
 239
 240
 241 /*
 242  * si470x_get_register - read register
 243  */
 244 static int si470x_get_register(struct si470x_device *radio, int regnr)
 245 {
 246         int retval;
 247
 248         radio->usb_buf[0] = REGISTER_REPORT(regnr);
 249
 250         retval = si470x_get_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE);
 251
 252         if (retval >= 0)
 253                 radio->registers[regnr] = get_unaligned_be16(&radio->usb_buf[1]);
 254
 255         return (retval < 0) ? -EINVAL : 0;
 256 }
 257
 258
 259 /*
 260  * si470x_set_register - write register
 261  */
 262 static int si470x_set_register(struct si470x_device *radio, int regnr)
 263 {
 264         int retval;
 265
 266         radio->usb_buf[0] = REGISTER_REPORT(regnr);
 267         put_unaligned_be16(radio->registers[regnr], &radio->usb_buf[1]);
 268
 269         retval = si470x_set_report(radio, radio->usb_buf, REGISTER_REPORT_SIZE);
 270
 271         return (retval < 0) ? -EINVAL : 0;
 272 }
 273
 274
 275
 276 /**************************************************************************
 277  * General Driver Functions - ENTIRE_REPORT
 278  **************************************************************************/
 279
 280 /*
 281  * si470x_get_all_registers - read entire registers
 282  */
 283 static int si470x_get_all_registers(struct si470x_device *radio)
 284 {
 285         int retval;
 286         unsigned char regnr;
 287
 288         radio->usb_buf[0] = ENTIRE_REPORT;
 289
 290         retval = si470x_get_report(radio, radio->usb_buf, ENTIRE_REPORT_SIZE);
 291
 292         if (retval >= 0)
 293                 for (regnr = 0; regnr < RADIO_REGISTER_NUM; regnr++)
 294                         radio->registers[regnr] = get_unaligned_be16(
 295                                 &radio->usb_buf[regnr * RADIO_REGISTER_SIZE + 1]);
 296
 297         return (retval < 0) ? -EINVAL : 0;
 298 }
 299
 300
 301
 302 /**************************************************************************
 303  * General Driver Functions - LED_REPORT
 304  **************************************************************************/
 305
 306 /*
 307  * si470x_set_led_state - sets the led state
 308  */
 309 static int si470x_set_led_state(struct si470x_device *radio,
 310                 unsigned char led_state)
 311 {
 312         int retval;
 313
 314         radio->usb_buf[0] = LED_REPORT;
 315         radio->usb_buf[1] = LED_COMMAND;
 316         radio->usb_buf[2] = led_state;
 317
 318         retval = si470x_set_report(radio, radio->usb_buf, LED_REPORT_SIZE);
 319
 320         return (retval < 0) ? -EINVAL : 0;
 321 }
 322
 323
 324
 325 /**************************************************************************
 326  * General Driver Functions - SCRATCH_REPORT
 327  **************************************************************************/
 328
 329 /*
 330  * si470x_get_scratch_versions - gets the scratch page and version infos
 331  */
 332 static int si470x_get_scratch_page_versions(struct si470x_device *radio)
 333 {
 334         int retval;
 335
 336         radio->usb_buf[0] = SCRATCH_REPORT;
 337
 338         retval = si470x_get_report(radio, radio->usb_buf, SCRATCH_REPORT_SIZE);
 339
 340         if (retval < 0)
 341                 dev_warn(&radio->intf->dev, "si470x_get_scratch: si470x_get_report returned %d\n",
 342                          retval);
 343         else {
 344                 radio->software_version = radio->usb_buf[1];
 345                 radio->hardware_version = radio->usb_buf[2];
 346         }
 347
 348         return (retval < 0) ? -EINVAL : 0;
 349 }
 350
 351
 352
 353 /**************************************************************************
 354  * RDS Driver Functions
 355  **************************************************************************/
 356
 357 /*
 358  * si470x_int_in_callback - rds callback and processing function
 359  *
 360  * TODO: do we need to use mutex locks in some sections?
 361  */
 362 static void si470x_int_in_callback(struct urb *urb)
 363 {
 364         struct si470x_device *radio = urb->context;
 365         int retval;
 366         unsigned char regnr;
 367         unsigned char blocknum;
 368         unsigned short bler; /* rds block errors */
 369         unsigned short rds;
 370         unsigned char tmpbuf[3];
 371
 372         if (urb->status) {
 373                 if (urb->status == -ENOENT ||
 374                                 urb->status == -ECONNRESET ||
 375                                 urb->status == -ESHUTDOWN) {
 376                         return;
 377                 } else {
 378                         dev_warn(&radio->intf->dev,
 379                          "non-zero urb status (%d)\n", urb->status);
 380                         goto resubmit; /* Maybe we can recover. */
 381                 }
 382         }
 383
 384         /* Sometimes the device returns len 0 packets */
 385         if (urb->actual_length != RDS_REPORT_SIZE)
 386                 goto resubmit;
 387
 388         radio->registers[STATUSRSSI] =
 389                 get_unaligned_be16(&radio->int_in_buffer[1]);
 390
 391         if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
 392                 complete(&radio->completion);
 393
 394         if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS)) {
 395                 /* Update RDS registers with URB data */
 396                 for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++)
 397                         radio->registers[STATUSRSSI + regnr] =
 398                             get_unaligned_be16(&radio->int_in_buffer[
 399                                 regnr * RADIO_REGISTER_SIZE + 1]);
 400                 /* get rds blocks */
 401                 if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSR) == 0) {
 402                         /* No RDS group ready, better luck next time */
 403                         goto resubmit;
 404                 }
 405                 if ((radio->registers[STATUSRSSI] & STATUSRSSI_RDSS) == 0) {
 406                         /* RDS decoder not synchronized */
 407                         goto resubmit;
 408                 }
 409                 for (blocknum = 0; blocknum < 4; blocknum++) {
 410                         switch (blocknum) {
 411                         default:
 412                                 bler = (radio->registers[STATUSRSSI] &
 413                                                 STATUSRSSI_BLERA) >> 9;
 414                                 rds = radio->registers[RDSA];
 415                                 break;
 416                         case 1:
 417                                 bler = (radio->registers[READCHAN] &
 418                                                 READCHAN_BLERB) >> 14;
 419                                 rds = radio->registers[RDSB];
 420                                 break;
 421                         case 2:
 422                                 bler = (radio->registers[READCHAN] &
 423                                                 READCHAN_BLERC) >> 12;
 424                                 rds = radio->registers[RDSC];
 425                                 break;
 426                         case 3:
 427                                 bler = (radio->registers[READCHAN] &
 428                                                 READCHAN_BLERD) >> 10;
 429                                 rds = radio->registers[RDSD];
 430                                 break;
 431                         }
 432
 433                         /* Fill the V4L2 RDS buffer */
 434                         put_unaligned_le16(rds, &tmpbuf);
 435                         tmpbuf[2] = blocknum;           /* offset name */
 436                         tmpbuf[2] |= blocknum << 3;     /* received offset */
 437                         if (bler > max_rds_errors)
 438                                 tmpbuf[2] |= 0x80; /* uncorrectable errors */
 439                         else if (bler > 0)
 440                                 tmpbuf[2] |= 0x40; /* corrected error(s) */
 441
 442                         /* copy RDS block to internal buffer */
 443                         memcpy(&radio->buffer[radio->wr_index], &tmpbuf, 3);
 444                         radio->wr_index += 3;
 445
 446                         /* wrap write pointer */
 447                         if (radio->wr_index >= radio->buf_size)
 448                                 radio->wr_index = 0;
 449
 450                         /* check for overflow */
 451                         if (radio->wr_index == radio->rd_index) {
 452                                 /* increment and wrap read pointer */
 453                                 radio->rd_index += 3;
 454                                 if (radio->rd_index >= radio->buf_size)
 455                                         radio->rd_index = 0;
 456                         }
 457                 }
 458                 if (radio->wr_index != radio->rd_index)
 459                         wake_up_interruptible(&radio->read_queue);
 460         }
 461
 462 resubmit:
 463         /* Resubmit if we're still running. */
 464         if (radio->int_in_running && radio->usbdev) {
 465                 retval = usb_submit_urb(radio->int_in_urb, GFP_ATOMIC);
 466                 if (retval) {
 467                         dev_warn(&radio->intf->dev,
 468                                "resubmitting urb failed (%d)", retval);
 469                         radio->int_in_running = 0;
 470                 }
 471         }
 472         radio->status_rssi_auto_update = radio->int_in_running;
 473 }
 474
 475
 476 static int si470x_fops_open(struct file *file)
 477 {
 478         return v4l2_fh_open(file);
 479 }
 480
 481 static int si470x_fops_release(struct file *file)
 482 {
 483         return v4l2_fh_release(file);
 484 }
 485
 486 static void si470x_usb_release(struct v4l2_device *v4l2_dev)
 487 {
 488         struct si470x_device *radio =
 489                 container_of(v4l2_dev, struct si470x_device, v4l2_dev);
 490
 491         usb_free_urb(radio->int_in_urb);
 492         v4l2_ctrl_handler_free(&radio->hdl);
 493         v4l2_device_unregister(&radio->v4l2_dev);
 494         kfree(radio->int_in_buffer);
 495         kfree(radio->buffer);
 496         kfree(radio->usb_buf);
 497         kfree(radio);
 498 }
 499
 500
 501 /**************************************************************************
 502  * Video4Linux Interface
 503  **************************************************************************/
 504
 505 /*
 506  * si470x_vidioc_querycap - query device capabilities
 507  */
 508 static int si470x_vidioc_querycap(struct file *file, void *priv,
 509                                   struct v4l2_capability *capability)
 510 {
 511         struct si470x_device *radio = video_drvdata(file);
 512
 513         strscpy(capability->driver, DRIVER_NAME, sizeof(capability->driver));
 514         strscpy(capability->card, DRIVER_CARD, sizeof(capability->card));
 515         usb_make_path(radio->usbdev, capability->bus_info,
 516                         sizeof(capability->bus_info));
 517         capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_READWRITE |
 518                 V4L2_CAP_TUNER | V4L2_CAP_RADIO | V4L2_CAP_RDS_CAPTURE;
 519         capability->capabilities = capability->device_caps | V4L2_CAP_DEVICE_CAPS;
 520         return 0;
 521 }
 522
 523
 524 static int si470x_start_usb(struct si470x_device *radio)
 525 {
 526         int retval;
 527
 528         /* initialize interrupt urb */
 529         usb_fill_int_urb(radio->int_in_urb, radio->usbdev,
 530                         usb_rcvintpipe(radio->usbdev,
 531                                 radio->int_in_endpoint->bEndpointAddress),
 532                         radio->int_in_buffer,
 533                         le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize),
 534                         si470x_int_in_callback,
 535                         radio,
 536                         radio->int_in_endpoint->bInterval);
 537
 538         radio->int_in_running = 1;
 539         mb();
 540
 541         retval = usb_submit_urb(radio->int_in_urb, GFP_KERNEL);
 542         if (retval) {
 543                 dev_info(&radio->intf->dev,
 544                                 "submitting int urb failed (%d)\n", retval);
 545                 radio->int_in_running = 0;
 546         }
 547         radio->status_rssi_auto_update = radio->int_in_running;
 548
 549         /* start radio */
 550         retval = si470x_start(radio);
 551         if (retval < 0)
 552                 return retval;
 553
 554         v4l2_ctrl_handler_setup(&radio->hdl);
 555
 556         return retval;
 557 }
 558
 559 /**************************************************************************
 560  * USB Interface
 561  **************************************************************************/
 562
 563 /*
 564  * si470x_usb_driver_probe - probe for the device
 565  */
 566 static int si470x_usb_driver_probe(struct usb_interface *intf,
 567                 const struct usb_device_id *id)
 568 {
 569         struct si470x_device *radio;
 570         struct usb_host_interface *iface_desc;
 571         struct usb_endpoint_descriptor *endpoint;
 572         int i, int_end_size, retval;
 573         unsigned char version_warning = 0;
 574
 575         /* private data allocation and initialization */
 576         radio = kzalloc(sizeof(struct si470x_device), GFP_KERNEL);
 577         if (!radio) {
 578                 retval = -ENOMEM;
 579                 goto err_initial;
 580         }
 581         radio->usb_buf = kmalloc(MAX_REPORT_SIZE, GFP_KERNEL);
 582         if (radio->usb_buf == NULL) {
 583                 retval = -ENOMEM;
 584                 goto err_radio;
 585         }
 586         radio->usbdev = interface_to_usbdev(intf);
 587         radio->intf = intf;
 588         radio->band = 1; /* Default to 76 - 108 MHz */
 589         mutex_init(&radio->lock);
 590         init_completion(&radio->completion);
 591
 592         radio->get_register = si470x_get_register;
 593         radio->set_register = si470x_set_register;
 594         radio->fops_open = si470x_fops_open;
 595         radio->fops_release = si470x_fops_release;
 596         radio->vidioc_querycap = si470x_vidioc_querycap;
 597
 598         iface_desc = intf->cur_altsetting;
 599
 600         /* Set up interrupt endpoint information. */
 601         for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 602                 endpoint = &iface_desc->endpoint[i].desc;
 603                 if (usb_endpoint_is_int_in(endpoint))
 604                         radio->int_in_endpoint = endpoint;
 605         }
 606         if (!radio->int_in_endpoint) {
 607                 dev_info(&intf->dev, "could not find interrupt in endpoint\n");
 608                 retval = -EIO;
 609                 goto err_usbbuf;
 610         }
 611
 612         int_end_size = le16_to_cpu(radio->int_in_endpoint->wMaxPacketSize);
 613
 614         radio->int_in_buffer = kmalloc(int_end_size, GFP_KERNEL);
 615         if (!radio->int_in_buffer) {
 616                 dev_info(&intf->dev, "could not allocate int_in_buffer");
 617                 retval = -ENOMEM;
 618                 goto err_usbbuf;
 619         }
 620
 621         radio->int_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 622         if (!radio->int_in_urb) {
 623                 retval = -ENOMEM;
 624                 goto err_intbuffer;
 625         }
 626
 627         radio->v4l2_dev.release = si470x_usb_release;
 628
 629         /*
 630          * The si470x SiLabs reference design uses the same USB IDs as
 631          * 'Thanko's Raremono' si4734 based receiver. So check here which we
 632          * have: attempt to read the device ID from the si470x: the lower 12
 633          * bits should be 0x0242 for the si470x.
 634          *
 635          * We use this check to determine which device we are dealing with.
 636          */
 637         if (id->idVendor == 0x10c4 && id->idProduct == 0x818a) {
 638                 retval = usb_control_msg(radio->usbdev,
 639                                 usb_rcvctrlpipe(radio->usbdev, 0),
 640                                 HID_REQ_GET_REPORT,
 641                                 USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
 642                                 1, 2,
 643                                 radio->usb_buf, 3, 500);
 644                 if (retval != 3 ||
 645                     (get_unaligned_be16(&radio->usb_buf[1]) & 0xfff) != 0x0242) {
 646                         dev_info(&intf->dev, "this is not a si470x device.\n");
 647                         retval = -ENODEV;
 648                         goto err_urb;
 649                 }
 650         }
 651
 652         retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 653         if (retval < 0) {
 654                 dev_err(&intf->dev, "couldn't register v4l2_device\n");
 655                 goto err_urb;
 656         }
 657
 658         v4l2_ctrl_handler_init(&radio->hdl, 2);
 659         v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
 660                           V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 661         v4l2_ctrl_new_std(&radio->hdl, &si470x_ctrl_ops,
 662                           V4L2_CID_AUDIO_VOLUME, 0, 15, 1, 15);
 663         if (radio->hdl.error) {
 664                 retval = radio->hdl.error;
 665                 dev_err(&intf->dev, "couldn't register control\n");
 666                 goto err_dev;
 667         }
 668         radio->videodev = si470x_viddev_template;
 669         radio->videodev.ctrl_handler = &radio->hdl;
 670         radio->videodev.lock = &radio->lock;
 671         radio->videodev.v4l2_dev = &radio->v4l2_dev;
 672         radio->videodev.release = video_device_release_empty;
 673         video_set_drvdata(&radio->videodev, radio);
 674
 675         /* get device and chip versions */
 676         if (si470x_get_all_registers(radio) < 0) {
 677                 retval = -EIO;
 678                 goto err_ctrl;
 679         }
 680         dev_info(&intf->dev, "DeviceID=0x%4.4hx ChipID=0x%4.4hx\n",
 681                         radio->registers[DEVICEID], radio->registers[SI_CHIPID]);
 682         if ((radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE) < RADIO_FW_VERSION) {
 683                 dev_warn(&intf->dev,
 684                         "This driver is known to work with firmware version %hu,\n",
 685                         RADIO_FW_VERSION);
 686                 dev_warn(&intf->dev,
 687                         "but the device has firmware version %hu.\n",
 688                         radio->registers[SI_CHIPID] & SI_CHIPID_FIRMWARE);
 689                 version_warning = 1;
 690         }
 691
 692         /* get software and hardware versions */
 693         if (si470x_get_scratch_page_versions(radio) < 0) {
 694                 retval = -EIO;
 695                 goto err_ctrl;
 696         }
 697         dev_info(&intf->dev, "software version %d, hardware version %d\n",
 698                         radio->software_version, radio->hardware_version);
 699         if (radio->hardware_version < RADIO_HW_VERSION) {
 700                 dev_warn(&intf->dev,
 701                         "This driver is known to work with hardware version %hu,\n",
 702                         RADIO_HW_VERSION);
 703                 dev_warn(&intf->dev,
 704                         "but the device has hardware version %hu.\n",
 705                         radio->hardware_version);
 706                 version_warning = 1;
 707         }
 708
 709         /* give out version warning */
 710         if (version_warning == 1) {
 711                 dev_warn(&intf->dev,
 712                         "If you have some trouble using this driver,\n");
 713                 dev_warn(&intf->dev,
 714                         "please report to V4L ML at linux-media@vger.kernel.org\n");
 715         }
 716
 717         /* set led to connect state */
 718         si470x_set_led_state(radio, BLINK_GREEN_LED);
 719
 720         /* rds buffer allocation */
 721         radio->buf_size = rds_buf * 3;
 722         radio->buffer = kmalloc(radio->buf_size, GFP_KERNEL);
 723         if (!radio->buffer) {
 724                 retval = -EIO;
 725                 goto err_ctrl;
 726         }
 727
 728         /* rds buffer configuration */
 729         radio->wr_index = 0;
 730         radio->rd_index = 0;
 731         init_waitqueue_head(&radio->read_queue);
 732         usb_set_intfdata(intf, radio);
 733
 734         /* start radio */
 735         retval = si470x_start_usb(radio);
 736         if (retval < 0)
 737                 goto err_all;
 738
 739         /* set initial frequency */
 740         si470x_set_freq(radio, 87.5 * FREQ_MUL); /* available in all regions */
 741
 742         /* register video device */
 743         retval = video_register_device(&radio->videodev, VFL_TYPE_RADIO,
 744                         radio_nr);
 745         if (retval) {
 746                 dev_err(&intf->dev, "Could not register video device\n");
 747                 goto err_all;
 748         }
 749
 750         return 0;
 751 err_all:
 752         kfree(radio->buffer);
 753 err_ctrl:
 754         v4l2_ctrl_handler_free(&radio->hdl);
 755 err_dev:
 756         v4l2_device_unregister(&radio->v4l2_dev);
 757 err_urb:
 758         usb_free_urb(radio->int_in_urb);
 759 err_intbuffer:
 760         kfree(radio->int_in_buffer);
 761 err_usbbuf:
 762         kfree(radio->usb_buf);
 763 err_radio:
 764         kfree(radio);
 765 err_initial:
 766         return retval;
 767 }
 768
 769
 770 /*
 771  * si470x_usb_driver_suspend - suspend the device
 772  */
 773 static int si470x_usb_driver_suspend(struct usb_interface *intf,
 774                 pm_message_t message)
 775 {
 776         struct si470x_device *radio = usb_get_intfdata(intf);
 777
 778         dev_info(&intf->dev, "suspending now...\n");
 779
 780         /* shutdown interrupt handler */
 781         if (radio->int_in_running) {
 782                 radio->int_in_running = 0;
 783                 if (radio->int_in_urb)
 784                         usb_kill_urb(radio->int_in_urb);
 785         }
 786
 787         /* cancel read processes */
 788         wake_up_interruptible(&radio->read_queue);
 789
 790         /* stop radio */
 791         si470x_stop(radio);
 792         return 0;
 793 }
 794
 795
 796 /*
 797  * si470x_usb_driver_resume - resume the device
 798  */
 799 static int si470x_usb_driver_resume(struct usb_interface *intf)
 800 {
 801         struct si470x_device *radio = usb_get_intfdata(intf);
 802         int ret;
 803
 804         dev_info(&intf->dev, "resuming now...\n");
 805
 806         /* start radio */
 807         ret = si470x_start_usb(radio);
 808         if (ret == 0)
 809                 v4l2_ctrl_handler_setup(&radio->hdl);
 810
 811         return ret;
 812 }
 813
 814
 815 /*
 816  * si470x_usb_driver_disconnect - disconnect the device
 817  */
 818 static void si470x_usb_driver_disconnect(struct usb_interface *intf)
 819 {
 820         struct si470x_device *radio = usb_get_intfdata(intf);
 821
 822         mutex_lock(&radio->lock);
 823         v4l2_device_disconnect(&radio->v4l2_dev);
 824         video_unregister_device(&radio->videodev);
 825         usb_set_intfdata(intf, NULL);
 826         mutex_unlock(&radio->lock);
 827         v4l2_device_put(&radio->v4l2_dev);
 828 }
 829
 830
 831 /*
 832  * si470x_usb_driver - usb driver interface
 833  *
 834  * A note on suspend/resume: this driver had only empty suspend/resume
 835  * functions, and when I tried to test suspend/resume it always disconnected
 836  * instead of resuming (using my ADS InstantFM stick). So I've decided to
 837  * remove these callbacks until someone else with better hardware can
 838  * implement and test this.
 839  */
 840 static struct usb_driver si470x_usb_driver = {
 841         .name                   = DRIVER_NAME,
 842         .probe                  = si470x_usb_driver_probe,
 843         .disconnect             = si470x_usb_driver_disconnect,
 844         .suspend                = si470x_usb_driver_suspend,
 845         .resume                 = si470x_usb_driver_resume,
 846         .reset_resume           = si470x_usb_driver_resume,
 847         .id_table               = si470x_usb_driver_id_table,
 848 };
 849
 850 module_usb_driver(si470x_usb_driver);
 851
 852 MODULE_LICENSE("GPL");
 853 MODULE_AUTHOR(DRIVER_AUTHOR);
 854 MODULE_DESCRIPTION(DRIVER_DESC);
 855 MODULE_VERSION(DRIVER_VERSION);