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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  *  You should have received a copy of the GNU General Public License
26  *  along with this program; if not, write to the Free Software
27  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
28  *
29  */
30 
31 #include <linux/export.h>
32 
33 #include "fmdrv.h"
34 #include "fmdrv_v4l2.h"
35 #include "fmdrv_common.h"
36 #include "fmdrv_rx.h"
37 #include "fmdrv_tx.h"
38 
39 static struct video_device *gradio_dev;
40 static u8 radio_disconnected;
41 
42 /* -- V4L2 RADIO (/dev/radioX) device file operation interfaces --- */
43 
44 /* Read RX RDS data */
fm_v4l2_fops_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)45 static ssize_t fm_v4l2_fops_read(struct file *file, char __user * buf,
46 					size_t count, loff_t *ppos)
47 {
48 	u8 rds_mode;
49 	int ret;
50 	struct fmdev *fmdev;
51 
52 	fmdev = video_drvdata(file);
53 
54 	if (!radio_disconnected) {
55 		fmerr("FM device is already disconnected\n");
56 		return -EIO;
57 	}
58 
59 	/* Turn on RDS mode , if it is disabled */
60 	ret = fm_rx_get_rds_mode(fmdev, &rds_mode);
61 	if (ret < 0) {
62 		fmerr("Unable to read current rds mode\n");
63 		return ret;
64 	}
65 
66 	if (rds_mode == FM_RDS_DISABLE) {
67 		ret = fmc_set_rds_mode(fmdev, FM_RDS_ENABLE);
68 		if (ret < 0) {
69 			fmerr("Failed to enable rds mode\n");
70 			return ret;
71 		}
72 	}
73 
74 	/* Copy RDS data from internal buffer to user buffer */
75 	return fmc_transfer_rds_from_internal_buff(fmdev, file, buf, count);
76 }
77 
78 /* Write TX RDS data */
fm_v4l2_fops_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)79 static ssize_t fm_v4l2_fops_write(struct file *file, const char __user * buf,
80 		size_t count, loff_t *ppos)
81 {
82 	struct tx_rds rds;
83 	int ret;
84 	struct fmdev *fmdev;
85 
86 	ret = copy_from_user(&rds, buf, sizeof(rds));
87 	rds.text[sizeof(rds.text) - 1] = '\0';
88 	fmdbg("(%d)type: %d, text %s, af %d\n",
89 		   ret, rds.text_type, rds.text, rds.af_freq);
90 	if (ret)
91 		return -EFAULT;
92 
93 	fmdev = video_drvdata(file);
94 	fm_tx_set_radio_text(fmdev, rds.text, rds.text_type);
95 	fm_tx_set_af(fmdev, rds.af_freq);
96 
97 	return sizeof(rds);
98 }
99 
fm_v4l2_fops_poll(struct file * file,struct poll_table_struct * pts)100 static u32 fm_v4l2_fops_poll(struct file *file, struct poll_table_struct *pts)
101 {
102 	int ret;
103 	struct fmdev *fmdev;
104 
105 	fmdev = video_drvdata(file);
106 	ret = fmc_is_rds_data_available(fmdev, file, pts);
107 	if (ret < 0)
108 		return POLLIN | POLLRDNORM;
109 
110 	return 0;
111 }
112 
113 /*
114  * Handle open request for "/dev/radioX" device.
115  * Start with FM RX mode as default.
116  */
fm_v4l2_fops_open(struct file * file)117 static int fm_v4l2_fops_open(struct file *file)
118 {
119 	int ret;
120 	struct fmdev *fmdev = NULL;
121 
122 	/* Don't allow multiple open */
123 	if (radio_disconnected) {
124 		fmerr("FM device is already opened\n");
125 		return -EBUSY;
126 	}
127 
128 	fmdev = video_drvdata(file);
129 
130 	ret = fmc_prepare(fmdev);
131 	if (ret < 0) {
132 		fmerr("Unable to prepare FM CORE\n");
133 		return ret;
134 	}
135 
136 	fmdbg("Load FM RX firmware..\n");
137 
138 	ret = fmc_set_mode(fmdev, FM_MODE_RX);
139 	if (ret < 0) {
140 		fmerr("Unable to load FM RX firmware\n");
141 		return ret;
142 	}
143 	radio_disconnected = 1;
144 
145 	return ret;
146 }
147 
fm_v4l2_fops_release(struct file * file)148 static int fm_v4l2_fops_release(struct file *file)
149 {
150 	int ret;
151 	struct fmdev *fmdev;
152 
153 	fmdev = video_drvdata(file);
154 	if (!radio_disconnected) {
155 		fmdbg("FM device is already closed\n");
156 		return 0;
157 	}
158 
159 	ret = fmc_set_mode(fmdev, FM_MODE_OFF);
160 	if (ret < 0) {
161 		fmerr("Unable to turn off the chip\n");
162 		return ret;
163 	}
164 
165 	ret = fmc_release(fmdev);
166 	if (ret < 0) {
167 		fmerr("FM CORE release failed\n");
168 		return ret;
169 	}
170 	radio_disconnected = 0;
171 
172 	return ret;
173 }
174 
175 /* V4L2 RADIO (/dev/radioX) device IOCTL interfaces */
fm_v4l2_vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * capability)176 static int fm_v4l2_vidioc_querycap(struct file *file, void *priv,
177 		struct v4l2_capability *capability)
178 {
179 	strlcpy(capability->driver, FM_DRV_NAME, sizeof(capability->driver));
180 	strlcpy(capability->card, FM_DRV_CARD_SHORT_NAME,
181 			sizeof(capability->card));
182 	sprintf(capability->bus_info, "UART");
183 	capability->capabilities = V4L2_CAP_HW_FREQ_SEEK | V4L2_CAP_TUNER |
184 		V4L2_CAP_RADIO | V4L2_CAP_MODULATOR |
185 		V4L2_CAP_AUDIO | V4L2_CAP_READWRITE |
186 		V4L2_CAP_RDS_CAPTURE;
187 
188 	return 0;
189 }
190 
fm_g_volatile_ctrl(struct v4l2_ctrl * ctrl)191 static int fm_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
192 {
193 	struct fmdev *fmdev = container_of(ctrl->handler,
194 			struct fmdev, ctrl_handler);
195 
196 	switch (ctrl->id) {
197 	case  V4L2_CID_TUNE_ANTENNA_CAPACITOR:
198 		ctrl->val = fm_tx_get_tune_cap_val(fmdev);
199 		break;
200 	default:
201 		fmwarn("%s: Unknown IOCTL: %d\n", __func__, ctrl->id);
202 		break;
203 	}
204 
205 	return 0;
206 }
207 
fm_v4l2_s_ctrl(struct v4l2_ctrl * ctrl)208 static int fm_v4l2_s_ctrl(struct v4l2_ctrl *ctrl)
209 {
210 	struct fmdev *fmdev = container_of(ctrl->handler,
211 			struct fmdev, ctrl_handler);
212 
213 	switch (ctrl->id) {
214 	case V4L2_CID_AUDIO_VOLUME:	/* set volume */
215 		return fm_rx_set_volume(fmdev, (u16)ctrl->val);
216 
217 	case V4L2_CID_AUDIO_MUTE:	/* set mute */
218 		return fmc_set_mute_mode(fmdev, (u8)ctrl->val);
219 
220 	case V4L2_CID_TUNE_POWER_LEVEL:
221 		/* set TX power level - ext control */
222 		return fm_tx_set_pwr_lvl(fmdev, (u8)ctrl->val);
223 
224 	case V4L2_CID_TUNE_PREEMPHASIS:
225 		return fm_tx_set_preemph_filter(fmdev, (u8) ctrl->val);
226 
227 	default:
228 		return -EINVAL;
229 	}
230 }
231 
fm_v4l2_vidioc_g_audio(struct file * file,void * priv,struct v4l2_audio * audio)232 static int fm_v4l2_vidioc_g_audio(struct file *file, void *priv,
233 		struct v4l2_audio *audio)
234 {
235 	memset(audio, 0, sizeof(*audio));
236 	strcpy(audio->name, "Radio");
237 	audio->capability = V4L2_AUDCAP_STEREO;
238 
239 	return 0;
240 }
241 
fm_v4l2_vidioc_s_audio(struct file * file,void * priv,struct v4l2_audio * audio)242 static int fm_v4l2_vidioc_s_audio(struct file *file, void *priv,
243 		struct v4l2_audio *audio)
244 {
245 	if (audio->index != 0)
246 		return -EINVAL;
247 
248 	return 0;
249 }
250 
251 /* Get tuner attributes. If current mode is NOT RX, return error */
fm_v4l2_vidioc_g_tuner(struct file * file,void * priv,struct v4l2_tuner * tuner)252 static int fm_v4l2_vidioc_g_tuner(struct file *file, void *priv,
253 		struct v4l2_tuner *tuner)
254 {
255 	struct fmdev *fmdev = video_drvdata(file);
256 	u32 bottom_freq;
257 	u32 top_freq;
258 	u16 stereo_mono_mode;
259 	u16 rssilvl;
260 	int ret;
261 
262 	if (tuner->index != 0)
263 		return -EINVAL;
264 
265 	if (fmdev->curr_fmmode != FM_MODE_RX)
266 		return -EPERM;
267 
268 	ret = fm_rx_get_band_freq_range(fmdev, &bottom_freq, &top_freq);
269 	if (ret != 0)
270 		return ret;
271 
272 	ret = fm_rx_get_stereo_mono(fmdev, &stereo_mono_mode);
273 	if (ret != 0)
274 		return ret;
275 
276 	ret = fm_rx_get_rssi_level(fmdev, &rssilvl);
277 	if (ret != 0)
278 		return ret;
279 
280 	strcpy(tuner->name, "FM");
281 	tuner->type = V4L2_TUNER_RADIO;
282 	/* Store rangelow and rangehigh freq in unit of 62.5 Hz */
283 	tuner->rangelow = bottom_freq * 16;
284 	tuner->rangehigh = top_freq * 16;
285 	tuner->rxsubchans = V4L2_TUNER_SUB_MONO | V4L2_TUNER_SUB_STEREO |
286 	((fmdev->rx.rds.flag == FM_RDS_ENABLE) ? V4L2_TUNER_SUB_RDS : 0);
287 	tuner->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
288 			    V4L2_TUNER_CAP_LOW;
289 	tuner->audmode = (stereo_mono_mode ?
290 			  V4L2_TUNER_MODE_MONO : V4L2_TUNER_MODE_STEREO);
291 
292 	/*
293 	 * Actual rssi value lies in between -128 to +127.
294 	 * Convert this range from 0 to 255 by adding +128
295 	 */
296 	rssilvl += 128;
297 
298 	/*
299 	 * Return signal strength value should be within 0 to 65535.
300 	 * Find out correct signal radio by multiplying (65535/255) = 257
301 	 */
302 	tuner->signal = rssilvl * 257;
303 	tuner->afc = 0;
304 
305 	return ret;
306 }
307 
308 /*
309  * Set tuner attributes. If current mode is NOT RX, set to RX.
310  * Currently, we set only audio mode (mono/stereo) and RDS state (on/off).
311  * Should we set other tuner attributes, too?
312  */
fm_v4l2_vidioc_s_tuner(struct file * file,void * priv,struct v4l2_tuner * tuner)313 static int fm_v4l2_vidioc_s_tuner(struct file *file, void *priv,
314 		struct v4l2_tuner *tuner)
315 {
316 	struct fmdev *fmdev = video_drvdata(file);
317 	u16 aud_mode;
318 	u8 rds_mode;
319 	int ret;
320 
321 	if (tuner->index != 0)
322 		return -EINVAL;
323 
324 	aud_mode = (tuner->audmode == V4L2_TUNER_MODE_STEREO) ?
325 			FM_STEREO_MODE : FM_MONO_MODE;
326 	rds_mode = (tuner->rxsubchans & V4L2_TUNER_SUB_RDS) ?
327 			FM_RDS_ENABLE : FM_RDS_DISABLE;
328 
329 	if (fmdev->curr_fmmode != FM_MODE_RX) {
330 		ret = fmc_set_mode(fmdev, FM_MODE_RX);
331 		if (ret < 0) {
332 			fmerr("Failed to set RX mode\n");
333 			return ret;
334 		}
335 	}
336 
337 	ret = fmc_set_stereo_mono(fmdev, aud_mode);
338 	if (ret < 0) {
339 		fmerr("Failed to set RX stereo/mono mode\n");
340 		return ret;
341 	}
342 
343 	ret = fmc_set_rds_mode(fmdev, rds_mode);
344 	if (ret < 0)
345 		fmerr("Failed to set RX RDS mode\n");
346 
347 	return ret;
348 }
349 
350 /* Get tuner or modulator radio frequency */
fm_v4l2_vidioc_g_freq(struct file * file,void * priv,struct v4l2_frequency * freq)351 static int fm_v4l2_vidioc_g_freq(struct file *file, void *priv,
352 		struct v4l2_frequency *freq)
353 {
354 	struct fmdev *fmdev = video_drvdata(file);
355 	int ret;
356 
357 	ret = fmc_get_freq(fmdev, &freq->frequency);
358 	if (ret < 0) {
359 		fmerr("Failed to get frequency\n");
360 		return ret;
361 	}
362 
363 	/* Frequency unit of 62.5 Hz*/
364 	freq->frequency = (u32) freq->frequency * 16;
365 
366 	return 0;
367 }
368 
369 /* Set tuner or modulator radio frequency */
fm_v4l2_vidioc_s_freq(struct file * file,void * priv,struct v4l2_frequency * freq)370 static int fm_v4l2_vidioc_s_freq(struct file *file, void *priv,
371 		struct v4l2_frequency *freq)
372 {
373 	struct fmdev *fmdev = video_drvdata(file);
374 
375 	/*
376 	 * As V4L2_TUNER_CAP_LOW is set 1 user sends the frequency
377 	 * in units of 62.5 Hz.
378 	 */
379 	freq->frequency = (u32)(freq->frequency / 16);
380 
381 	return fmc_set_freq(fmdev, freq->frequency);
382 }
383 
384 /* Set hardware frequency seek. If current mode is NOT RX, set it RX. */
fm_v4l2_vidioc_s_hw_freq_seek(struct file * file,void * priv,struct v4l2_hw_freq_seek * seek)385 static int fm_v4l2_vidioc_s_hw_freq_seek(struct file *file, void *priv,
386 		struct v4l2_hw_freq_seek *seek)
387 {
388 	struct fmdev *fmdev = video_drvdata(file);
389 	int ret;
390 
391 	if (fmdev->curr_fmmode != FM_MODE_RX) {
392 		ret = fmc_set_mode(fmdev, FM_MODE_RX);
393 		if (ret != 0) {
394 			fmerr("Failed to set RX mode\n");
395 			return ret;
396 		}
397 	}
398 
399 	ret = fm_rx_seek(fmdev, seek->seek_upward, seek->wrap_around,
400 			seek->spacing);
401 	if (ret < 0)
402 		fmerr("RX seek failed - %d\n", ret);
403 
404 	return ret;
405 }
406 /* Get modulator attributes. If mode is not TX, return no attributes. */
fm_v4l2_vidioc_g_modulator(struct file * file,void * priv,struct v4l2_modulator * mod)407 static int fm_v4l2_vidioc_g_modulator(struct file *file, void *priv,
408 		struct v4l2_modulator *mod)
409 {
410 	struct fmdev *fmdev = video_drvdata(file);
411 
412 	if (mod->index != 0)
413 		return -EINVAL;
414 
415 	if (fmdev->curr_fmmode != FM_MODE_TX)
416 		return -EPERM;
417 
418 	mod->txsubchans = ((fmdev->tx_data.aud_mode == FM_STEREO_MODE) ?
419 				V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO) |
420 				((fmdev->tx_data.rds.flag == FM_RDS_ENABLE) ?
421 				V4L2_TUNER_SUB_RDS : 0);
422 
423 	mod->capability = V4L2_TUNER_CAP_STEREO | V4L2_TUNER_CAP_RDS |
424 				V4L2_TUNER_CAP_LOW;
425 
426 	return 0;
427 }
428 
429 /* Set modulator attributes. If mode is not TX, set to TX. */
fm_v4l2_vidioc_s_modulator(struct file * file,void * priv,struct v4l2_modulator * mod)430 static int fm_v4l2_vidioc_s_modulator(struct file *file, void *priv,
431 		struct v4l2_modulator *mod)
432 {
433 	struct fmdev *fmdev = video_drvdata(file);
434 	u8 rds_mode;
435 	u16 aud_mode;
436 	int ret;
437 
438 	if (mod->index != 0)
439 		return -EINVAL;
440 
441 	if (fmdev->curr_fmmode != FM_MODE_TX) {
442 		ret = fmc_set_mode(fmdev, FM_MODE_TX);
443 		if (ret != 0) {
444 			fmerr("Failed to set TX mode\n");
445 			return ret;
446 		}
447 	}
448 
449 	aud_mode = (mod->txsubchans & V4L2_TUNER_SUB_STEREO) ?
450 			FM_STEREO_MODE : FM_MONO_MODE;
451 	rds_mode = (mod->txsubchans & V4L2_TUNER_SUB_RDS) ?
452 			FM_RDS_ENABLE : FM_RDS_DISABLE;
453 	ret = fm_tx_set_stereo_mono(fmdev, aud_mode);
454 	if (ret < 0) {
455 		fmerr("Failed to set mono/stereo mode for TX\n");
456 		return ret;
457 	}
458 	ret = fm_tx_set_rds_mode(fmdev, rds_mode);
459 	if (ret < 0)
460 		fmerr("Failed to set rds mode for TX\n");
461 
462 	return ret;
463 }
464 
465 static const struct v4l2_file_operations fm_drv_fops = {
466 	.owner = THIS_MODULE,
467 	.read = fm_v4l2_fops_read,
468 	.write = fm_v4l2_fops_write,
469 	.poll = fm_v4l2_fops_poll,
470 	.unlocked_ioctl = video_ioctl2,
471 	.open = fm_v4l2_fops_open,
472 	.release = fm_v4l2_fops_release,
473 };
474 
475 static const struct v4l2_ctrl_ops fm_ctrl_ops = {
476 	.s_ctrl = fm_v4l2_s_ctrl,
477 	.g_volatile_ctrl = fm_g_volatile_ctrl,
478 };
479 static const struct v4l2_ioctl_ops fm_drv_ioctl_ops = {
480 	.vidioc_querycap = fm_v4l2_vidioc_querycap,
481 	.vidioc_g_audio = fm_v4l2_vidioc_g_audio,
482 	.vidioc_s_audio = fm_v4l2_vidioc_s_audio,
483 	.vidioc_g_tuner = fm_v4l2_vidioc_g_tuner,
484 	.vidioc_s_tuner = fm_v4l2_vidioc_s_tuner,
485 	.vidioc_g_frequency = fm_v4l2_vidioc_g_freq,
486 	.vidioc_s_frequency = fm_v4l2_vidioc_s_freq,
487 	.vidioc_s_hw_freq_seek = fm_v4l2_vidioc_s_hw_freq_seek,
488 	.vidioc_g_modulator = fm_v4l2_vidioc_g_modulator,
489 	.vidioc_s_modulator = fm_v4l2_vidioc_s_modulator
490 };
491 
492 /* V4L2 RADIO device parent structure */
493 static struct video_device fm_viddev_template = {
494 	.fops = &fm_drv_fops,
495 	.ioctl_ops = &fm_drv_ioctl_ops,
496 	.name = FM_DRV_NAME,
497 	.release = video_device_release,
498 };
499 
fm_v4l2_init_video_device(struct fmdev * fmdev,int radio_nr)500 int fm_v4l2_init_video_device(struct fmdev *fmdev, int radio_nr)
501 {
502 	struct v4l2_ctrl *ctrl;
503 	int ret;
504 
505 	/* Init mutex for core locking */
506 	mutex_init(&fmdev->mutex);
507 
508 	/* Allocate new video device */
509 	gradio_dev = video_device_alloc();
510 	if (NULL == gradio_dev) {
511 		fmerr("Can't allocate video device\n");
512 		return -ENOMEM;
513 	}
514 
515 	/* Setup FM driver's V4L2 properties */
516 	memcpy(gradio_dev, &fm_viddev_template, sizeof(fm_viddev_template));
517 
518 	video_set_drvdata(gradio_dev, fmdev);
519 
520 	gradio_dev->lock = &fmdev->mutex;
521 
522 	/* Register with V4L2 subsystem as RADIO device */
523 	if (video_register_device(gradio_dev, VFL_TYPE_RADIO, radio_nr)) {
524 		video_device_release(gradio_dev);
525 		fmerr("Could not register video device\n");
526 		return -ENOMEM;
527 	}
528 
529 	fmdev->radio_dev = gradio_dev;
530 
531 	/* Register to v4l2 ctrl handler framework */
532 	fmdev->radio_dev->ctrl_handler = &fmdev->ctrl_handler;
533 
534 	ret = v4l2_ctrl_handler_init(&fmdev->ctrl_handler, 5);
535 	if (ret < 0) {
536 		fmerr("(fmdev): Can't init ctrl handler\n");
537 		v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
538 		return -EBUSY;
539 	}
540 
541 	/*
542 	 * Following controls are handled by V4L2 control framework.
543 	 * Added in ascending ID order.
544 	 */
545 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
546 			V4L2_CID_AUDIO_VOLUME, FM_RX_VOLUME_MIN,
547 			FM_RX_VOLUME_MAX, 1, FM_RX_VOLUME_MAX);
548 
549 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
550 			V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
551 
552 	v4l2_ctrl_new_std_menu(&fmdev->ctrl_handler, &fm_ctrl_ops,
553 			V4L2_CID_TUNE_PREEMPHASIS, V4L2_PREEMPHASIS_75_uS,
554 			0, V4L2_PREEMPHASIS_75_uS);
555 
556 	v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
557 			V4L2_CID_TUNE_POWER_LEVEL, FM_PWR_LVL_LOW,
558 			FM_PWR_LVL_HIGH, 1, FM_PWR_LVL_HIGH);
559 
560 	ctrl = v4l2_ctrl_new_std(&fmdev->ctrl_handler, &fm_ctrl_ops,
561 			V4L2_CID_TUNE_ANTENNA_CAPACITOR, 0,
562 			255, 1, 255);
563 
564 	if (ctrl)
565 		ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
566 
567 	return 0;
568 }
569 
fm_v4l2_deinit_video_device(void)570 void *fm_v4l2_deinit_video_device(void)
571 {
572 	struct fmdev *fmdev;
573 
574 
575 	fmdev = video_get_drvdata(gradio_dev);
576 
577 	/* Unregister to v4l2 ctrl handler framework*/
578 	v4l2_ctrl_handler_free(&fmdev->ctrl_handler);
579 
580 	/* Unregister RADIO device from V4L2 subsystem */
581 	video_unregister_device(gradio_dev);
582 
583 	return fmdev;
584 }
585