linux/drivers/media/radio/wl128x/fmdrv_v4l2.c
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   1/*
   2 *  FM Driver for Connectivity chip of Texas Instruments.
   3 *  This file provides interfaces to V4L2 subsystem.
   4 *
   5 *  This module registers with V4L2 subsystem as Radio
   6 *  data system interface (/dev/radio). During the registration,
   7 *  it will expose two set of function pointers.
   8 *
   9 *    1) File operation related API (open, close, read, write, poll...etc).
  10 *    2) Set of V4L2 IOCTL complaint API.
  11 *
  12 *  Copyright (C) 2011 Texas Instruments
  13 *  Author: Raja Mani <raja_mani@ti.com>
  14 *  Author: Manjunatha Halli <manjunatha_halli@ti.com>
  15 *
  16 *  This program is free software; you can redistribute it and/or modify
  17 *  it under the terms of the GNU General Public License version 2 as
  18 *  published by the Free Software Foundation.
  19 *
  20 *  This program is distributed in the hope that it will be useful,
  21 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  22 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23 *  GNU General Public License for more details.
  24 *
  25 */
  26
  27#include <linux/export.h>
  28
  29#include "fmdrv.h"
  30#include "fmdrv_v4l2.h"
  31#include "fmdrv_common.h"
  32#include "fmdrv_rx.h"
  33#include "fmdrv_tx.h"
  34
  35static struct video_device gradio_dev;
  36static u8 radio_disconnected;
  37
  38/* -- V4L2 RADIO (/dev/radioX) device file operation interfaces --- */
  39
  40/* Read RX RDS data */
  41static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
  42                                        size_t count, loff_t *ppos)
  43{
  44        u8 rds_mode;
  45        int ret;
  46        struct fmdev *fmdev;
  47
  48        fmdev = video_drvdata(file);
  49
  50        if (!radio_disconnected) {
  51                fmerr("FM device is already disconnected\n");
  52                return -EIO;
  53        }
  54
  55        if (mutex_lock_interruptible(&fmdev->mutex))
  56                return -ERESTARTSYS;
  57
  58        /* Turn on RDS mode if it is disabled */
  59        ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
  60        if (ret < 0) {
  61                fmerr("Unable to read current rds mode\n");
  62                goto read_unlock;
  63        }
  64
  65        if (rds_mode == FM_RDS_DISABLE) {
  66                ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
  67                if (ret < 0) {
  68                        fmerr("Failed to enable rds mode\n");
  69                        goto read_unlock;
  70                }
  71        }
  72
  73        /* Copy RDS data from internal buffer to user buffer */
  74        ret = fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
  75read_unlock:
  76        mutex_unlock(&fmdev->mutex);
  77        return ret;
  78}
  79
  80/* Write TX RDS data */
  81static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
  82                size_t count, loff_t *ppos)
  83{
  84        struct tx_rds rds;
  85        int ret;
  86        struct fmdev *fmdev;
  87
  88        ret = copy_from_user(&rds, buf, sizeof(rds));
  89        rds.text[sizeof(rds.text) - 1] = '\0';
  90        fmdbg("(%d)type: %d, text %s, af %d\n",
  91                   ret, rds.text_type, rds.text, rds.af_freq);
  92        if (ret)
  93                return -EFAULT;
  94
  95        fmdev = video_drvdata(file);
  96        if (mutex_lock_interruptible(&fmdev->mutex))
  97                return -ERESTARTSYS;
  98        fm_tx_set_radio_text(fmdev, rds.text, rds.text_type);
  99        fm_tx_set_af(fmdev, rds.af_freq);
 100        mutex_unlock(&fmdev->mutex);
 101
 102        return sizeof(rds);
 103}
 104
 105static u32 fm_v4l2_fops_poll(struct file *file, struct poll_table_struct *pts)
 106{
 107        int ret;
 108        struct fmdev *fmdev;
 109
 110        fmdev = video_drvdata(file);
 111        mutex_lock(&fmdev->mutex);
 112        ret = fmc_is_rds_data_available(fmdev, file, pts);
 113        mutex_unlock(&fmdev->mutex);
 114        if (ret < 0)
 115                return POLLIN | POLLRDNORM;
 116
 117        return 0;
 118}
 119
 120/*
 121 * Handle open request for "/dev/radioX" device.
 122 * Start with FM RX mode as default.
 123 */
 124static int fm_v4l2_fops_open(struct file *file)
 125{
 126        int ret;
 127        struct fmdev *fmdev = NULL;
 128
 129        /* Don't allow multiple open */
 130        if (radio_disconnected) {
 131                fmerr("FM device is already opened\n");
 132                return -EBUSY;
 133        }
 134
 135        fmdev = video_drvdata(file);
 136
 137        if (mutex_lock_interruptible(&fmdev->mutex))
 138                return -ERESTARTSYS;
 139        ret = fmc_prepare(fmdev);
 140        if (ret < 0) {
 141                fmerr("Unable to prepare FM CORE\n");
 142                goto open_unlock;
 143        }
 144
 145        fmdbg("Load FM RX firmware..\n");
 146
 147        ret = fmc_set_mode(fmdev, FM_MODE_RX);
 148        if (ret < 0) {
 149                fmerr("Unable to load FM RX firmware\n");
 150                goto open_unlock;
 151        }
 152        radio_disconnected = 1;
 153
 154open_unlock:
 155        mutex_unlock(&fmdev->mutex);
 156        return ret;
 157}
 158
 159static int fm_v4l2_fops_release(struct file *file)
 160{
 161        int ret;
 162        struct fmdev *fmdev;
 163
 164        fmdev = video_drvdata(file);
 165        if (!radio_disconnected) {
 166                fmdbg("FM device is already closed\n");
 167                return 0;
 168        }
 169
 170        mutex_lock(&fmdev->mutex);
 171        ret = fmc_set_mode(fmdev, FM_MODE_OFF);
 172        if (ret < 0) {
 173                fmerr("Unable to turn off the chip\n");
 174                goto release_unlock;
 175        }
 176
 177        ret = fmc_release(fmdev);
 178        if (ret < 0) {
 179                fmerr("FM CORE release failed\n");
 180                goto release_unlock;
 181        }
 182        radio_disconnected = 0;
 183
 184release_unlock:
 185        mutex_unlock(&fmdev->mutex);
 186        return ret;
 187}
 188
 189/* V4L2 RADIO (/dev/radioX) device IOCTL interfaces */
 190static int fm_v4l2_vidioc_querycap(struct file *file, void *priv,
 191                struct v4l2_capability *capability)
 192{
 193        strlcpy(capability->driver, FM_DRV_NAME, sizeof(capability->driver));
 194        strlcpy(capability->card, FM_DRV_CARD_SHORT_NAME,
 195                        sizeof(capability->card));
 196        sprintf(capability->bus_info, "UART");
 197        capability->device_caps = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER |
 198                V4L2_CAP_RADIO | V4L2_CAP_MODULATOR |
 199                V4L2_CAP_AUDIO | V4L2_CAP_READWRITE |
 200                V4L2_CAP_RDS_CAPTURE;
 201        capability->capabilities = capability->device_caps |
 202                V4L2_CAP_DEVICE_CAPS;
 203
 204        return 0;
 205}
 206
 207static int fm_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
 208{
 209        struct fmdev *fmdev = container_of(ctrl->handler,
 210                        struct fmdev, ctrl_handler);
 211
 212        switch (ctrl->id) {
 213        case  V4L2_CID_TUNE_ANTENNA_CAPACITOR:
 214                ctrl->val = fm_tx_get_tune_cap_val(fmdev);
 215                break;
 216        default:
 217                fmwarn("%s: Unknown IOCTL: %d\n", __func__, ctrl->id);
 218                break;
 219        }
 220
 221        return 0;
 222}
 223
 224static int fm_v4l2_s_ctrl(struct v4l2_ctrl *ctrl)
 225{
 226        struct fmdev *fmdev = container_of(ctrl->handler,
 227                        struct fmdev, ctrl_handler);
 228
 229        switch (ctrl->id) {
 230        case V4L2_CID_AUDIO_VOLUME:     /* set volume */
 231                return fm_rx_set_volume(fmdev, (u16)ctrl->val);
 232
 233        case V4L2_CID_AUDIO_MUTE:       /* set mute */
 234                return fmc_set_mute_mode(fmdev, (u8)ctrl->val);
 235
 236        case V4L2_CID_TUNE_POWER_LEVEL:
 237                /* set TX power level - ext control */
 238                return fm_tx_set_pwr_lvl(fmdev, (u8)ctrl->val);
 239
 240        case V4L2_CID_TUNE_PREEMPHASIS:
 241                return fm_tx_set_preemph_filter(fmdev, (u8) ctrl->val);
 242
 243        default:
 244                return -EINVAL;
 245        }
 246}
 247
 248static int fm_v4l2_vidioc_g_audio(struct file *file, void *priv,
 249                struct v4l2_audio *audio)
 250{
 251        memset(audio, 0, sizeof(*audio));
 252        strcpy(audio->name, "Radio");
 253        audio->capability = V4L2_AUDCAP_STEREO;
 254
 255        return 0;
 256}
 257
 258static int fm_v4l2_vidioc_s_audio(struct file *file, void *priv,
 259                const struct v4l2_audio *audio)
 260{
 261        if (audio->index != 0)
 262                return -EINVAL;
 263
 264        return 0;
 265}
 266
 267/* Get tuner attributes. If current mode is NOT RX, return error */
 268static int fm_v4l2_vidioc_g_tuner(struct file *file, void *priv,
 269                struct v4l2_tuner *tuner)
 270{
 271        struct fmdev *fmdev = video_drvdata(file);
 272        u32 bottom_freq;
 273        u32 top_freq;
 274        u16 stereo_mono_mode;
 275        u16 rssilvl;
 276        int ret;
 277
 278        if (tuner->index != 0)
 279                return -EINVAL;
 280
 281        if (fmdev->curr_fmmode != FM_MODE_RX)
 282                return -EPERM;
 283
 284        ret = fm_rx_get_band_freq_range(fmdev, &bottom_freq, &top_freq);
 285        if (ret != 0)
 286                return ret;
 287
 288        ret = fm_rx_get_stereo_mono(fmdev, &stereo_mono_mode);
 289        if (ret != 0)
 290                return ret;
 291
 292        ret = fm_rx_get_rssi_level(fmdev, &rssilvl);
 293        if (ret != 0)
 294                return ret;
 295
 296        strcpy(tuner->name, "FM");
 297        tuner->type = V4L2_TUNER_RADIO;
 298        /* Store rangelow and rangehigh freq in unit of 62.5 Hz */
 299        tuner->rangelow = bottom_freq * 16;
 300        tuner->rangehigh = top_freq * 16;
 301        tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO |
 302        ((fmdev->rx.rds.flag == FM_RDS_ENABLE) ? V4L2_TUNER_SUB_RDS : 0);
 303        tuner->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
 304                            V4L2_TUNER_CAP_LOW |
 305                            V4L2_TUNER_CAP_HWSEEK_BOUNDED |
 306                            V4L2_TUNER_CAP_HWSEEK_WRAP;
 307        tuner->audmode = (stereo_mono_mode ?
 308                          V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO);
 309
 310        /*
 311         * Actual rssi value lies in between -128 to +127.
 312         * Convert this range from 0 to 255 by adding +128
 313         */
 314        rssilvl += 128;
 315
 316        /*
 317         * Return signal strength value should be within 0 to 65535.
 318         * Find out correct signal radio by multiplying (65535/255) = 257
 319         */
 320        tuner->signal = rssilvl * 257;
 321        tuner->afc = 0;
 322
 323        return ret;
 324}
 325
 326/*
 327 * Set tuner attributes. If current mode is NOT RX, set to RX.
 328 * Currently, we set only audio mode (mono/stereo) and RDS state (on/off).
 329 * Should we set other tuner attributes, too?
 330 */
 331static int fm_v4l2_vidioc_s_tuner(struct file *file, void *priv,
 332                const struct v4l2_tuner *tuner)
 333{
 334        struct fmdev *fmdev = video_drvdata(file);
 335        u16 aud_mode;
 336        u8 rds_mode;
 337        int ret;
 338
 339        if (tuner->index != 0)
 340                return -EINVAL;
 341
 342        aud_mode = (tuner->audmode == V4L2_TUNER_MODE_STEREO) ?
 343                        FM_STEREO_MODE : FM_MONO_MODE;
 344        rds_mode = (tuner->rxsubchans & V4L2_TUNER_SUB_RDS) ?
 345                        FM_RDS_ENABLE : FM_RDS_DISABLE;
 346
 347        if (fmdev->curr_fmmode != FM_MODE_RX) {
 348                ret = fmc_set_mode(fmdev, FM_MODE_RX);
 349                if (ret < 0) {
 350                        fmerr("Failed to set RX mode\n");
 351                        return ret;
 352                }
 353        }
 354
 355        ret = fmc_set_stereo_mono(fmdev, aud_mode);
 356        if (ret < 0) {
 357                fmerr("Failed to set RX stereo/mono mode\n");
 358                return ret;
 359        }
 360
 361        ret = fmc_set_rds_mode(fmdev, rds_mode);
 362        if (ret < 0)
 363                fmerr("Failed to set RX RDS mode\n");
 364
 365        return ret;
 366}
 367
 368/* Get tuner or modulator radio frequency */
 369static int fm_v4l2_vidioc_g_freq(struct file *file, void *priv,
 370                struct v4l2_frequency *freq)
 371{
 372        struct fmdev *fmdev = video_drvdata(file);
 373        int ret;
 374
 375        ret = fmc_get_freq(fmdev, &freq->frequency);
 376        if (ret < 0) {
 377                fmerr("Failed to get frequency\n");
 378                return ret;
 379        }
 380
 381        /* Frequency unit of 62.5 Hz*/
 382        freq->frequency = (u32) freq->frequency * 16;
 383
 384        return 0;
 385}
 386
 387/* Set tuner or modulator radio frequency */
 388static int fm_v4l2_vidioc_s_freq(struct file *file, void *priv,
 389                const struct v4l2_frequency *freq)
 390{
 391        struct fmdev *fmdev = video_drvdata(file);
 392
 393        /*
 394         * As V4L2_TUNER_CAP_LOW is set 1 user sends the frequency
 395         * in units of 62.5 Hz.
 396         */
 397        return fmc_set_freq(fmdev, freq->frequency / 16);
 398}
 399
 400/* Set hardware frequency seek. If current mode is NOT RX, set it RX. */
 401static int fm_v4l2_vidioc_s_hw_freq_seek(struct file *file, void *priv,
 402                const struct v4l2_hw_freq_seek *seek)
 403{
 404        struct fmdev *fmdev = video_drvdata(file);
 405        int ret;
 406
 407        if (file->f_flags & O_NONBLOCK)
 408                return -EWOULDBLOCK;
 409
 410        if (fmdev->curr_fmmode != FM_MODE_RX) {
 411                ret = fmc_set_mode(fmdev, FM_MODE_RX);
 412                if (ret != 0) {
 413                        fmerr("Failed to set RX mode\n");
 414                        return ret;
 415                }
 416        }
 417
 418        ret = fm_rx_seek(fmdev, seek->seek_upward, seek->wrap_around,
 419                        seek->spacing);
 420        if (ret < 0)
 421                fmerr("RX seek failed - %d\n", ret);
 422
 423        return ret;
 424}
 425/* Get modulator attributes. If mode is not TX, return no attributes. */
 426static int fm_v4l2_vidioc_g_modulator(struct file *file, void *priv,
 427                struct v4l2_modulator *mod)
 428{
 429        struct fmdev *fmdev = video_drvdata(file);
 430
 431        if (mod->index != 0)
 432                return -EINVAL;
 433
 434        if (fmdev->curr_fmmode != FM_MODE_TX)
 435                return -EPERM;
 436
 437        mod->txsubchans = ((fmdev->tx_data.aud_mode == FM_STEREO_MODE) ?
 438                                V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO) |
 439                                ((fmdev->tx_data.rds.flag == FM_RDS_ENABLE) ?
 440                                V4L2_TUNER_SUB_RDS : 0);
 441
 442        mod->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
 443                                V4L2_TUNER_CAP_LOW;
 444
 445        return 0;
 446}
 447
 448/* Set modulator attributes. If mode is not TX, set to TX. */
 449static int fm_v4l2_vidioc_s_modulator(struct file *file, void *priv,
 450                const struct v4l2_modulator *mod)
 451{
 452        struct fmdev *fmdev = video_drvdata(file);
 453        u8 rds_mode;
 454        u16 aud_mode;
 455        int ret;
 456
 457        if (mod->index != 0)
 458                return -EINVAL;
 459
 460        if (fmdev->curr_fmmode != FM_MODE_TX) {
 461                ret = fmc_set_mode(fmdev, FM_MODE_TX);
 462                if (ret != 0) {
 463                        fmerr("Failed to set TX mode\n");
 464                        return ret;
 465                }
 466        }
 467
 468        aud_mode = (mod->txsubchans & V4L2_TUNER_SUB_STEREO) ?
 469                        FM_STEREO_MODE : FM_MONO_MODE;
 470        rds_mode = (mod->txsubchans & V4L2_TUNER_SUB_RDS) ?
 471                        FM_RDS_ENABLE : FM_RDS_DISABLE;
 472        ret = fm_tx_set_stereo_mono(fmdev, aud_mode);
 473        if (ret < 0) {
 474                fmerr("Failed to set mono/stereo mode for TX\n");
 475                return ret;
 476        }
 477        ret = fm_tx_set_rds_mode(fmdev, rds_mode);
 478        if (ret < 0)
 479                fmerr("Failed to set rds mode for TX\n");
 480
 481        return ret;
 482}
 483
 484static const struct v4l2_file_operations fm_drv_fops = {
 485        .owner = THIS_MODULE,
 486        .read = fm_v4l2_fops_read,
 487        .write = fm_v4l2_fops_write,
 488        .poll = fm_v4l2_fops_poll,
 489        .unlocked_ioctl = video_ioctl2,
 490        .open = fm_v4l2_fops_open,
 491        .release = fm_v4l2_fops_release,
 492};
 493
 494static const struct v4l2_ctrl_ops fm_ctrl_ops = {
 495        .s_ctrl = fm_v4l2_s_ctrl,
 496        .g_volatile_ctrl = fm_g_volatile_ctrl,
 497};
 498static const struct v4l2_ioctl_ops fm_drv_ioctl_ops = {
 499        .vidioc_querycap = fm_v4l2_vidioc_querycap,
 500        .vidioc_g_audio = fm_v4l2_vidioc_g_audio,
 501        .vidioc_s_audio = fm_v4l2_vidioc_s_audio,
 502        .vidioc_g_tuner = fm_v4l2_vidioc_g_tuner,
 503        .vidioc_s_tuner = fm_v4l2_vidioc_s_tuner,
 504        .vidioc_g_frequency = fm_v4l2_vidioc_g_freq,
 505        .vidioc_s_frequency = fm_v4l2_vidioc_s_freq,
 506        .vidioc_s_hw_freq_seek = fm_v4l2_vidioc_s_hw_freq_seek,
 507        .vidioc_g_modulator = fm_v4l2_vidioc_g_modulator,
 508        .vidioc_s_modulator = fm_v4l2_vidioc_s_modulator
 509};
 510
 511/* V4L2 RADIO device parent structure */
 512static struct video_device fm_viddev_template = {
 513        .fops = &fm_drv_fops,
 514        .ioctl_ops = &fm_drv_ioctl_ops,
 515        .name = FM_DRV_NAME,
 516        .release = video_device_release_empty,
 517        /*
 518         * To ensure both the tuner and modulator ioctls are accessible we
 519         * set the vfl_dir to M2M to indicate this.
 520         *
 521         * It is not really a mem2mem device of course, but it can both receive
 522         * and transmit using the same radio device. It's the only radio driver
 523         * that does this and it should really be split in two radio devices,
 524         * but that would affect applications using this driver.
 525         */
 526        .vfl_dir = VFL_DIR_M2M,
 527};
 528
 529int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr)
 530{
 531        struct v4l2_ctrl *ctrl;
 532        int ret;
 533
 534        strlcpy(fmdev->v4l2_dev.name, FM_DRV_NAME, sizeof(fmdev->v4l2_dev.name));
 535        ret = v4l2_device_register(NULL, &fmdev->v4l2_dev);
 536        if (ret < 0)
 537                return ret;
 538
 539        /* Init mutex for core locking */
 540        mutex_init(&fmdev->mutex);
 541
 542        /* Setup FM driver's V4L2 properties */
 543        gradio_dev = fm_viddev_template;
 544
 545        video_set_drvdata(&gradio_dev, fmdev);
 546
 547        gradio_dev.lock = &fmdev->mutex;
 548        gradio_dev.v4l2_dev = &fmdev->v4l2_dev;
 549
 550        /* Register with V4L2 subsystem as RADIO device */
 551        if (video_register_device(&gradio_dev, VFL_TYPE_RADIO, radio_nr)) {
 552                fmerr("Could not register video device\n");
 553                return -ENOMEM;
 554        }
 555
 556        fmdev->radio_dev = &gradio_dev;
 557
 558        /* Register to v4l2 ctrl handler framework */
 559        fmdev->radio_dev->ctrl_handler = &fmdev->ctrl_handler;
 560
 561        ret = v4l2_ctrl_handler_init(&fmdev->ctrl_handler, 5);
 562        if (ret < 0) {
 563                fmerr("(fmdev): Can't init ctrl handler\n");
 564                v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
 565                return -EBUSY;
 566        }
 567
 568        /*
 569         * Following controls are handled by V4L2 control framework.
 570         * Added in ascending ID order.
 571         */
 572        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
 573                        V4L2_CID_AUDIO_VOLUME, FM_RX_VOLUME_MIN,
 574                        FM_RX_VOLUME_MAX, 1, FM_RX_VOLUME_MAX);
 575
 576        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
 577                        V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
 578
 579        v4l2_ctrl_new_std_menu(&fmdev->ctrl_handler, &fm_ctrl_ops,
 580                        V4L2_CID_TUNE_PREEMPHASIS, V4L2_PREEMPHASIS_75_uS,
 581                        0, V4L2_PREEMPHASIS_75_uS);
 582
 583        v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
 584                        V4L2_CID_TUNE_POWER_LEVEL, FM_PWR_LVL_LOW,
 585                        FM_PWR_LVL_HIGH, 1, FM_PWR_LVL_HIGH);
 586
 587        ctrl = v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
 588                        V4L2_CID_TUNE_ANTENNA_CAPACITOR, 0,
 589                        255, 1, 255);
 590
 591        if (ctrl)
 592                ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
 593
 594        return 0;
 595}
 596
 597void *fm_v4l2_deinit_video_device(void)
 598{
 599        struct fmdev *fmdev;
 600
 601
 602        fmdev = video_get_drvdata(&gradio_dev);
 603
 604        /* Unregister to v4l2 ctrl handler framework*/
 605        v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
 606
 607        /* Unregister RADIO device from V4L2 subsystem */
 608        video_unregister_device(&gradio_dev);
 609
 610        v4l2_device_unregister(&fmdev->v4l2_dev);
 611
 612        return fmdev;
 613}
 614