drivers/media/radio/si4713/radio-usb-si4713.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2013 Cisco Systems, Inc. and/or its affiliates.
   4  * All rights reserved.
   5  */
   6
   7 /* kernel includes */
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/usb.h>
  11 #include <linux/init.h>
  12 #include <linux/slab.h>
  13 #include <linux/input.h>
  14 #include <linux/mutex.h>
  15 #include <linux/i2c.h>
  16 /* V4l includes */
  17 #include <linux/videodev2.h>
  18 #include <media/v4l2-common.h>
  19 #include <media/v4l2-device.h>
  20 #include <media/v4l2-ioctl.h>
  21 #include <media/v4l2-event.h>
  22 #include <linux/platform_data/media/si4713.h>
  23
  24 #include "si4713.h"
  25
  26 /* driver and module definitions */
  27 MODULE_AUTHOR("Dinesh Ram <dinesh.ram@cern.ch>");
  28 MODULE_DESCRIPTION("Si4713 FM Transmitter USB driver");
  29 MODULE_LICENSE("GPL v2");
  30
  31 /* The Device announces itself as Cygnal Integrated Products, Inc. */
  32 #define USB_SI4713_VENDOR               0x10c4
  33 #define USB_SI4713_PRODUCT              0x8244
  34
  35 #define BUFFER_LENGTH                   64
  36 #define USB_TIMEOUT                     1000
  37 #define USB_RESP_TIMEOUT                50000
  38
  39 /* USB Device ID List */
  40 static const struct usb_device_id usb_si4713_usb_device_table[] = {
  41         {USB_DEVICE_AND_INTERFACE_INFO(USB_SI4713_VENDOR, USB_SI4713_PRODUCT,
  42                                                         USB_CLASS_HID, 0, 0) },
  43         { }                                             /* Terminating entry */
  44 };
  45
  46 MODULE_DEVICE_TABLE(usb, usb_si4713_usb_device_table);
  47
  48 struct si4713_usb_device {
  49         struct usb_device       *usbdev;
  50         struct usb_interface    *intf;
  51         struct video_device     vdev;
  52         struct v4l2_device      v4l2_dev;
  53         struct v4l2_subdev      *v4l2_subdev;
  54         struct mutex            lock;
  55         struct i2c_adapter      i2c_adapter;
  56
  57         u8                      *buffer;
  58 };
  59
  60 static inline struct si4713_usb_device *to_si4713_dev(struct v4l2_device *v4l2_dev)
  61 {
  62         return container_of(v4l2_dev, struct si4713_usb_device, v4l2_dev);
  63 }
  64
  65 static int vidioc_querycap(struct file *file, void *priv,
  66                                         struct v4l2_capability *v)
  67 {
  68         struct si4713_usb_device *radio = video_drvdata(file);
  69
  70         strlcpy(v->driver, "radio-usb-si4713", sizeof(v->driver));
  71         strlcpy(v->card, "Si4713 FM Transmitter", sizeof(v->card));
  72         usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
  73         v->device_caps = V4L2_CAP_MODULATOR | V4L2_CAP_RDS_OUTPUT;
  74         v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
  75
  76         return 0;
  77 }
  78
  79 static int vidioc_g_modulator(struct file *file, void *priv,
  80                                 struct v4l2_modulator *vm)
  81 {
  82         struct si4713_usb_device *radio = video_drvdata(file);
  83
  84         return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_modulator, vm);
  85 }
  86
  87 static int vidioc_s_modulator(struct file *file, void *priv,
  88                                 const struct v4l2_modulator *vm)
  89 {
  90         struct si4713_usb_device *radio = video_drvdata(file);
  91
  92         return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_modulator, vm);
  93 }
  94
  95 static int vidioc_s_frequency(struct file *file, void *priv,
  96                                 const struct v4l2_frequency *vf)
  97 {
  98         struct si4713_usb_device *radio = video_drvdata(file);
  99
 100         return v4l2_subdev_call(radio->v4l2_subdev, tuner, s_frequency, vf);
 101 }
 102
 103 static int vidioc_g_frequency(struct file *file, void *priv,
 104                                 struct v4l2_frequency *vf)
 105 {
 106         struct si4713_usb_device *radio = video_drvdata(file);
 107
 108         return v4l2_subdev_call(radio->v4l2_subdev, tuner, g_frequency, vf);
 109 }
 110
 111 static const struct v4l2_ioctl_ops usb_si4713_ioctl_ops = {
 112         .vidioc_querycap          = vidioc_querycap,
 113         .vidioc_g_modulator       = vidioc_g_modulator,
 114         .vidioc_s_modulator       = vidioc_s_modulator,
 115         .vidioc_g_frequency       = vidioc_g_frequency,
 116         .vidioc_s_frequency       = vidioc_s_frequency,
 117         .vidioc_log_status        = v4l2_ctrl_log_status,
 118         .vidioc_subscribe_event   = v4l2_ctrl_subscribe_event,
 119         .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
 120 };
 121
 122 /* File system interface */
 123 static const struct v4l2_file_operations usb_si4713_fops = {
 124         .owner          = THIS_MODULE,
 125         .open           = v4l2_fh_open,
 126         .release        = v4l2_fh_release,
 127         .poll           = v4l2_ctrl_poll,
 128         .unlocked_ioctl = video_ioctl2,
 129 };
 130
 131 static void usb_si4713_video_device_release(struct v4l2_device *v4l2_dev)
 132 {
 133         struct si4713_usb_device *radio = to_si4713_dev(v4l2_dev);
 134         struct i2c_adapter *adapter = &radio->i2c_adapter;
 135
 136         i2c_del_adapter(adapter);
 137         v4l2_device_unregister(&radio->v4l2_dev);
 138         kfree(radio->buffer);
 139         kfree(radio);
 140 }
 141
 142 /*
 143  * This command sequence emulates the behaviour of the Windows driver.
 144  * The structure of these commands was determined by sniffing the
 145  * usb traffic of the device during startup.
 146  * Most likely, these commands make some queries to the device.
 147  * Commands are sent to enquire parameters like the bus mode,
 148  * component revision, boot mode, the device serial number etc.
 149  *
 150  * These commands are necessary to be sent in this order during startup.
 151  * The device fails to powerup if these commands are not sent.
 152  *
 153  * The complete list of startup commands is given in the start_seq table below.
 154  */
 155 static int si4713_send_startup_command(struct si4713_usb_device *radio)
 156 {
 157         unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
 158         u8 *buffer = radio->buffer;
 159         int retval;
 160
 161         /* send the command */
 162         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 163                                         0x09, 0x21, 0x033f, 0, radio->buffer,
 164                                         BUFFER_LENGTH, USB_TIMEOUT);
 165         if (retval < 0)
 166                 return retval;
 167
 168         for (;;) {
 169                 /* receive the response */
 170                 retval = usb_control_msg(radio->usbdev, usb_rcvctrlpipe(radio->usbdev, 0),
 171                                 0x01, 0xa1, 0x033f, 0, radio->buffer,
 172                                 BUFFER_LENGTH, USB_TIMEOUT);
 173                 if (retval < 0)
 174                         return retval;
 175                 if (!radio->buffer[1]) {
 176                         /* USB traffic sniffing showed that some commands require
 177                          * additional checks. */
 178                         switch (buffer[1]) {
 179                         case 0x32:
 180                                 if (radio->buffer[2] == 0)
 181                                         return 0;
 182                                 break;
 183                         case 0x14:
 184                         case 0x12:
 185                                 if (radio->buffer[2] & SI4713_CTS)
 186                                         return 0;
 187                                 break;
 188                         case 0x06:
 189                                 if ((radio->buffer[2] & SI4713_CTS) && radio->buffer[9] == 0x08)
 190                                         return 0;
 191                                 break;
 192                         default:
 193                                 return 0;
 194                         }
 195                 }
 196                 if (time_is_before_jiffies(until_jiffies))
 197                         return -EIO;
 198                 msleep(3);
 199         }
 200
 201         return retval;
 202 }
 203
 204 struct si4713_start_seq_table {
 205         int len;
 206         u8 payload[8];
 207 };
 208
 209 /*
 210  * Some of the startup commands that could be recognized are :
 211  * (0x03): Get serial number of the board (Response : CB000-00-00)
 212  * (0x06, 0x03, 0x03, 0x08, 0x01, 0x0f) : Get Component revision
 213  */
 214 static const struct si4713_start_seq_table start_seq[] = {
 215
 216         { 1, { 0x03 } },
 217         { 2, { 0x32, 0x7f } },
 218         { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
 219         { 2, { 0x14, 0x02 } },
 220         { 2, { 0x09, 0x90 } },
 221         { 3, { 0x08, 0x90, 0xfa } },
 222         { 2, { 0x36, 0x01 } },
 223         { 2, { 0x05, 0x03 } },
 224         { 7, { 0x06, 0x00, 0x06, 0x0e, 0x01, 0x0f, 0x05 } },
 225         { 1, { 0x12 } },
 226         /* Commands that are sent after pressing the 'Initialize'
 227                 button in the windows application */
 228         { 1, { 0x03 } },
 229         { 1, { 0x01 } },
 230         { 2, { 0x09, 0x90 } },
 231         { 3, { 0x08, 0x90, 0xfa } },
 232         { 1, { 0x34 } },
 233         { 2, { 0x35, 0x01 } },
 234         { 2, { 0x36, 0x01 } },
 235         { 2, { 0x30, 0x09 } },
 236         { 4, { 0x30, 0x06, 0x00, 0xe2 } },
 237         { 3, { 0x31, 0x01, 0x30 } },
 238         { 3, { 0x31, 0x04, 0x09 } },
 239         { 2, { 0x05, 0x02 } },
 240         { 6, { 0x06, 0x03, 0x03, 0x08, 0x01, 0x0f } },
 241 };
 242
 243 static int si4713_start_seq(struct si4713_usb_device *radio)
 244 {
 245         int retval = 0;
 246         int i;
 247
 248         radio->buffer[0] = 0x3f;
 249
 250         for (i = 0; i < ARRAY_SIZE(start_seq); i++) {
 251                 int len = start_seq[i].len;
 252                 const u8 *payload = start_seq[i].payload;
 253
 254                 memcpy(radio->buffer + 1, payload, len);
 255                 memset(radio->buffer + len + 1, 0, BUFFER_LENGTH - 1 - len);
 256                 retval = si4713_send_startup_command(radio);
 257         }
 258
 259         return retval;
 260 }
 261
 262 static struct i2c_board_info si4713_board_info = {
 263         I2C_BOARD_INFO("si4713", SI4713_I2C_ADDR_BUSEN_HIGH),
 264 };
 265
 266 struct si4713_command_table {
 267         int command_id;
 268         u8 payload[8];
 269 };
 270
 271 /*
 272  * Structure of a command :
 273  *      Byte 1 : 0x3f (always)
 274  *      Byte 2 : 0x06 (send a command)
 275  *      Byte 3 : Unknown
 276  *      Byte 4 : Number of arguments + 1 (for the command byte)
 277  *      Byte 5 : Number of response bytes
 278  */
 279 static struct si4713_command_table command_table[] = {
 280
 281         { SI4713_CMD_POWER_UP,          { 0x00, SI4713_PWUP_NARGS + 1, SI4713_PWUP_NRESP} },
 282         { SI4713_CMD_GET_REV,           { 0x03, 0x01, SI4713_GETREV_NRESP } },
 283         { SI4713_CMD_POWER_DOWN,        { 0x00, 0x01, SI4713_PWDN_NRESP} },
 284         { SI4713_CMD_SET_PROPERTY,      { 0x00, SI4713_SET_PROP_NARGS + 1, SI4713_SET_PROP_NRESP } },
 285         { SI4713_CMD_GET_PROPERTY,      { 0x00, SI4713_GET_PROP_NARGS + 1, SI4713_GET_PROP_NRESP } },
 286         { SI4713_CMD_TX_TUNE_FREQ,      { 0x03, SI4713_TXFREQ_NARGS + 1, SI4713_TXFREQ_NRESP } },
 287         { SI4713_CMD_TX_TUNE_POWER,     { 0x03, SI4713_TXPWR_NARGS + 1, SI4713_TXPWR_NRESP } },
 288         { SI4713_CMD_TX_TUNE_MEASURE,   { 0x03, SI4713_TXMEA_NARGS + 1, SI4713_TXMEA_NRESP } },
 289         { SI4713_CMD_TX_TUNE_STATUS,    { 0x00, SI4713_TXSTATUS_NARGS + 1, SI4713_TXSTATUS_NRESP } },
 290         { SI4713_CMD_TX_ASQ_STATUS,     { 0x03, SI4713_ASQSTATUS_NARGS + 1, SI4713_ASQSTATUS_NRESP } },
 291         { SI4713_CMD_GET_INT_STATUS,    { 0x03, 0x01, SI4713_GET_STATUS_NRESP } },
 292         { SI4713_CMD_TX_RDS_BUFF,       { 0x03, SI4713_RDSBUFF_NARGS + 1, SI4713_RDSBUFF_NRESP } },
 293         { SI4713_CMD_TX_RDS_PS,         { 0x00, SI4713_RDSPS_NARGS + 1, SI4713_RDSPS_NRESP } },
 294 };
 295
 296 static int send_command(struct si4713_usb_device *radio, u8 *payload, char *data, int len)
 297 {
 298         int retval;
 299
 300         radio->buffer[0] = 0x3f;
 301         radio->buffer[1] = 0x06;
 302
 303         memcpy(radio->buffer + 2, payload, 3);
 304         memcpy(radio->buffer + 5, data, len);
 305         memset(radio->buffer + 5 + len, 0, BUFFER_LENGTH - 5 - len);
 306
 307         /* send the command */
 308         retval = usb_control_msg(radio->usbdev, usb_sndctrlpipe(radio->usbdev, 0),
 309                                         0x09, 0x21, 0x033f, 0, radio->buffer,
 310                                         BUFFER_LENGTH, USB_TIMEOUT);
 311
 312         return retval < 0 ? retval : 0;
 313 }
 314
 315 static int si4713_i2c_read(struct si4713_usb_device *radio, char *data, int len)
 316 {
 317         unsigned long until_jiffies = jiffies + usecs_to_jiffies(USB_RESP_TIMEOUT) + 1;
 318         int retval;
 319
 320         /* receive the response */
 321         for (;;) {
 322                 retval = usb_control_msg(radio->usbdev,
 323                                         usb_rcvctrlpipe(radio->usbdev, 0),
 324                                         0x01, 0xa1, 0x033f, 0, radio->buffer,
 325                                         BUFFER_LENGTH, USB_TIMEOUT);
 326                 if (retval < 0)
 327                         return retval;
 328
 329                 /*
 330                  * Check that we get a valid reply back (buffer[1] == 0) and
 331                  * that CTS is set before returning, otherwise we wait and try
 332                  * again. The i2c driver also does the CTS check, but the timeouts
 333                  * used there are much too small for this USB driver, so we wait
 334                  * for it here.
 335                  */
 336                 if (radio->buffer[1] == 0 && (radio->buffer[2] & SI4713_CTS)) {
 337                         memcpy(data, radio->buffer + 2, len);
 338                         return 0;
 339                 }
 340                 if (time_is_before_jiffies(until_jiffies)) {
 341                         /* Zero the status value, ensuring CTS isn't set */
 342                         data[0] = 0;
 343                         return 0;
 344                 }
 345                 msleep(3);
 346         }
 347 }
 348
 349 static int si4713_i2c_write(struct si4713_usb_device *radio, char *data, int len)
 350 {
 351         int retval = -EINVAL;
 352         int i;
 353
 354         if (len > BUFFER_LENGTH - 5)
 355                 return -EINVAL;
 356
 357         for (i = 0; i < ARRAY_SIZE(command_table); i++) {
 358                 if (data[0] == command_table[i].command_id)
 359                         retval = send_command(radio, command_table[i].payload,
 360                                                 data, len);
 361         }
 362
 363         return retval < 0 ? retval : 0;
 364 }
 365
 366 static int si4713_transfer(struct i2c_adapter *i2c_adapter,
 367                                 struct i2c_msg *msgs, int num)
 368 {
 369         struct si4713_usb_device *radio = i2c_get_adapdata(i2c_adapter);
 370         int retval = -EINVAL;
 371         int i;
 372
 373         for (i = 0; i < num; i++) {
 374                 if (msgs[i].flags & I2C_M_RD)
 375                         retval = si4713_i2c_read(radio, msgs[i].buf, msgs[i].len);
 376                 else
 377                         retval = si4713_i2c_write(radio, msgs[i].buf, msgs[i].len);
 378                 if (retval)
 379                         break;
 380         }
 381
 382         return retval ? retval : num;
 383 }
 384
 385 static u32 si4713_functionality(struct i2c_adapter *adapter)
 386 {
 387         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 388 }
 389
 390 static const struct i2c_algorithm si4713_algo = {
 391         .master_xfer   = si4713_transfer,
 392         .functionality = si4713_functionality,
 393 };
 394
 395 /* This name value shows up in the sysfs filename associated
 396                 with this I2C adapter */
 397 static const struct i2c_adapter si4713_i2c_adapter_template = {
 398         .name   = "si4713-i2c",
 399         .owner  = THIS_MODULE,
 400         .algo   = &si4713_algo,
 401 };
 402
 403 static int si4713_register_i2c_adapter(struct si4713_usb_device *radio)
 404 {
 405         radio->i2c_adapter = si4713_i2c_adapter_template;
 406         /* set up sysfs linkage to our parent device */
 407         radio->i2c_adapter.dev.parent = &radio->usbdev->dev;
 408         i2c_set_adapdata(&radio->i2c_adapter, radio);
 409
 410         return i2c_add_adapter(&radio->i2c_adapter);
 411 }
 412
 413 /* check if the device is present and register with v4l and usb if it is */
 414 static int usb_si4713_probe(struct usb_interface *intf,
 415                                 const struct usb_device_id *id)
 416 {
 417         struct si4713_usb_device *radio;
 418         struct i2c_adapter *adapter;
 419         struct v4l2_subdev *sd;
 420         int retval = -ENOMEM;
 421
 422         dev_info(&intf->dev, "Si4713 development board discovered: (%04X:%04X)\n",
 423                         id->idVendor, id->idProduct);
 424
 425         /* Initialize local device structure */
 426         radio = kzalloc(sizeof(struct si4713_usb_device), GFP_KERNEL);
 427         if (radio)
 428                 radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
 429
 430         if (!radio || !radio->buffer) {
 431                 dev_err(&intf->dev, "kmalloc for si4713_usb_device failed\n");
 432                 kfree(radio);
 433                 return -ENOMEM;
 434         }
 435
 436         mutex_init(&radio->lock);
 437
 438         radio->usbdev = interface_to_usbdev(intf);
 439         radio->intf = intf;
 440         usb_set_intfdata(intf, &radio->v4l2_dev);
 441
 442         retval = si4713_start_seq(radio);
 443         if (retval < 0)
 444                 goto err_v4l2;
 445
 446         retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
 447         if (retval < 0) {
 448                 dev_err(&intf->dev, "couldn't register v4l2_device\n");
 449                 goto err_v4l2;
 450         }
 451
 452         retval = si4713_register_i2c_adapter(radio);
 453         if (retval < 0) {
 454                 dev_err(&intf->dev, "could not register i2c device\n");
 455                 goto err_i2cdev;
 456         }
 457
 458         adapter = &radio->i2c_adapter;
 459         sd = v4l2_i2c_new_subdev_board(&radio->v4l2_dev, adapter,
 460                                           &si4713_board_info, NULL);
 461         radio->v4l2_subdev = sd;
 462         if (!sd) {
 463                 dev_err(&intf->dev, "cannot get v4l2 subdevice\n");
 464                 retval = -ENODEV;
 465                 goto del_adapter;
 466         }
 467
 468         radio->vdev.ctrl_handler = sd->ctrl_handler;
 469         radio->v4l2_dev.release = usb_si4713_video_device_release;
 470         strlcpy(radio->vdev.name, radio->v4l2_dev.name,
 471                 sizeof(radio->vdev.name));
 472         radio->vdev.v4l2_dev = &radio->v4l2_dev;
 473         radio->vdev.fops = &usb_si4713_fops;
 474         radio->vdev.ioctl_ops = &usb_si4713_ioctl_ops;
 475         radio->vdev.lock = &radio->lock;
 476         radio->vdev.release = video_device_release_empty;
 477         radio->vdev.vfl_dir = VFL_DIR_TX;
 478
 479         video_set_drvdata(&radio->vdev, radio);
 480
 481         retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO, -1);
 482         if (retval < 0) {
 483                 dev_err(&intf->dev, "could not register video device\n");
 484                 goto del_adapter;
 485         }
 486
 487         dev_info(&intf->dev, "V4L2 device registered as %s\n",
 488                         video_device_node_name(&radio->vdev));
 489
 490         return 0;
 491
 492 del_adapter:
 493         i2c_del_adapter(adapter);
 494 err_i2cdev:
 495         v4l2_device_unregister(&radio->v4l2_dev);
 496 err_v4l2:
 497         kfree(radio->buffer);
 498         kfree(radio);
 499         return retval;
 500 }
 501
 502 static void usb_si4713_disconnect(struct usb_interface *intf)
 503 {
 504         struct si4713_usb_device *radio = to_si4713_dev(usb_get_intfdata(intf));
 505
 506         dev_info(&intf->dev, "Si4713 development board now disconnected\n");
 507
 508         mutex_lock(&radio->lock);
 509         usb_set_intfdata(intf, NULL);
 510         video_unregister_device(&radio->vdev);
 511         v4l2_device_disconnect(&radio->v4l2_dev);
 512         mutex_unlock(&radio->lock);
 513         v4l2_device_put(&radio->v4l2_dev);
 514 }
 515
 516 /* USB subsystem interface */
 517 static struct usb_driver usb_si4713_driver = {
 518         .name                   = "radio-usb-si4713",
 519         .probe                  = usb_si4713_probe,
 520         .disconnect             = usb_si4713_disconnect,
 521         .id_table               = usb_si4713_usb_device_table,
 522 };
 523
 524 module_usb_driver(usb_si4713_driver);