1 /*
2  * A driver for the AverMedia MR 800 USB FM radio. This device plugs
3  * into both the USB and an analog audio input, so this thing
4  * only deals with initialization and frequency setting, the
5  * audio data has to be handled by a sound driver.
6  *
7  * Copyright (c) 2008 Alexey Klimov <klimov.linux@gmail.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 /*
21  * Big thanks to authors and contributors of dsbr100.c and radio-si470x.c
22  *
23  * When work was looked pretty good, i discover this:
24  * http://av-usbradio.sourceforge.net/index.php
25  * http://sourceforge.net/projects/av-usbradio/
26  * Latest release of theirs project was in 2005.
27  * Probably, this driver could be improved through using their
28  * achievements (specifications given).
29  * Also, Faidon Liambotis <paravoid@debian.org> wrote nice driver for this radio
30  * in 2007. He allowed to use his driver to improve current mr800 radio driver.
31  * http://www.spinics.net/lists/linux-usb-devel/msg10109.html
32  *
33  * Version 0.01:	First working version.
34  *			It's required to blacklist AverMedia USB Radio
35  *			in usbhid/hid-quirks.c
36  * Version 0.10:	A lot of cleanups and fixes: unpluging the device,
37  *			few mutex locks were added, codinstyle issues, etc.
38  *			Added stereo support. Thanks to
39  *			Douglas Schilling Landgraf <dougsland@gmail.com> and
40  *			David Ellingsworth <david@identd.dyndns.org>
41  *			for discussion, help and support.
42  * Version 0.11:	Converted to v4l2_device.
43  *
44  * Many things to do:
45  *	- Correct power management of device (suspend & resume)
46  *	- Add code for scanning and smooth tuning
47  *	- Add code for sensitivity value
48  *	- Correct mistakes
49  *	- In Japan another FREQ_MIN and FREQ_MAX
50  */
51 
52 /* kernel includes */
53 #include <linux/kernel.h>
54 #include <linux/module.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #include <linux/input.h>
58 #include <linux/videodev2.h>
59 #include <media/v4l2-device.h>
60 #include <media/v4l2-ioctl.h>
61 #include <media/v4l2-ctrls.h>
62 #include <media/v4l2-event.h>
63 #include <linux/usb.h>
64 #include <linux/mutex.h>
65 
66 /* driver and module definitions */
67 #define DRIVER_AUTHOR "Alexey Klimov <klimov.linux@gmail.com>"
68 #define DRIVER_DESC "AverMedia MR 800 USB FM radio driver"
69 #define DRIVER_VERSION "0.1.2"
70 
71 MODULE_AUTHOR(DRIVER_AUTHOR);
72 MODULE_DESCRIPTION(DRIVER_DESC);
73 MODULE_LICENSE("GPL");
74 MODULE_VERSION(DRIVER_VERSION);
75 
76 #define USB_AMRADIO_VENDOR 0x07ca
77 #define USB_AMRADIO_PRODUCT 0xb800
78 
79 /* dev_warn macro with driver name */
80 #define MR800_DRIVER_NAME "radio-mr800"
81 #define amradio_dev_warn(dev, fmt, arg...)				\
82 		dev_warn(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
83 
84 #define amradio_dev_err(dev, fmt, arg...) \
85 		dev_err(dev, MR800_DRIVER_NAME " - " fmt, ##arg)
86 
87 /* Probably USB_TIMEOUT should be modified in module parameter */
88 #define BUFFER_LENGTH 8
89 #define USB_TIMEOUT 500
90 
91 /* Frequency limits in MHz -- these are European values.  For Japanese
92 devices, that would be 76 and 91.  */
93 #define FREQ_MIN  87.5
94 #define FREQ_MAX 108.0
95 #define FREQ_MUL 16000
96 
97 /*
98  * Commands that device should understand
99  * List isn't full and will be updated with implementation of new functions
100  */
101 #define AMRADIO_SET_FREQ	0xa4
102 #define AMRADIO_GET_READY_FLAG	0xa5
103 #define AMRADIO_GET_SIGNAL	0xa7
104 #define AMRADIO_GET_FREQ	0xa8
105 #define AMRADIO_SET_SEARCH_UP	0xa9
106 #define AMRADIO_SET_SEARCH_DOWN	0xaa
107 #define AMRADIO_SET_MUTE	0xab
108 #define AMRADIO_SET_RIGHT_MUTE	0xac
109 #define AMRADIO_SET_LEFT_MUTE	0xad
110 #define AMRADIO_SET_MONO	0xae
111 #define AMRADIO_SET_SEARCH_LVL	0xb0
112 #define AMRADIO_STOP_SEARCH	0xb1
113 
114 /* Comfortable defines for amradio_set_stereo */
115 #define WANT_STEREO		0x00
116 #define WANT_MONO		0x01
117 
118 /* module parameter */
119 static int radio_nr = -1;
120 module_param(radio_nr, int, 0);
121 MODULE_PARM_DESC(radio_nr, "Radio Nr");
122 
123 /* Data for one (physical) device */
124 struct amradio_device {
125 	/* reference to USB and video device */
126 	struct usb_device *usbdev;
127 	struct usb_interface *intf;
128 	struct video_device vdev;
129 	struct v4l2_device v4l2_dev;
130 	struct v4l2_ctrl_handler hdl;
131 
132 	u8 *buffer;
133 	struct mutex lock;	/* buffer locking */
134 	int curfreq;
135 	int stereo;
136 	int muted;
137 };
138 
to_amradio_dev(struct v4l2_device * v4l2_dev)139 static inline struct amradio_device *to_amradio_dev(struct v4l2_device *v4l2_dev)
140 {
141 	return container_of(v4l2_dev, struct amradio_device, v4l2_dev);
142 }
143 
amradio_send_cmd(struct amradio_device * radio,u8 cmd,u8 arg,u8 * extra,u8 extralen,bool reply)144 static int amradio_send_cmd(struct amradio_device *radio, u8 cmd, u8 arg,
145 		u8 *extra, u8 extralen, bool reply)
146 {
147 	int retval;
148 	int size;
149 
150 	radio->buffer[0] = 0x00;
151 	radio->buffer[1] = 0x55;
152 	radio->buffer[2] = 0xaa;
153 	radio->buffer[3] = extralen;
154 	radio->buffer[4] = cmd;
155 	radio->buffer[5] = arg;
156 	radio->buffer[6] = 0x00;
157 	radio->buffer[7] = extra || reply ? 8 : 0;
158 
159 	retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
160 		radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
161 
162 	if (retval < 0 || size != BUFFER_LENGTH) {
163 		if (video_is_registered(&radio->vdev))
164 			amradio_dev_warn(&radio->vdev.dev,
165 					"cmd %02x failed\n", cmd);
166 		return retval ? retval : -EIO;
167 	}
168 	if (!extra && !reply)
169 		return 0;
170 
171 	if (extra) {
172 		memcpy(radio->buffer, extra, extralen);
173 		memset(radio->buffer + extralen, 0, 8 - extralen);
174 		retval = usb_bulk_msg(radio->usbdev, usb_sndintpipe(radio->usbdev, 2),
175 			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
176 	} else {
177 		memset(radio->buffer, 0, 8);
178 		retval = usb_bulk_msg(radio->usbdev, usb_rcvbulkpipe(radio->usbdev, 0x81),
179 			radio->buffer, BUFFER_LENGTH, &size, USB_TIMEOUT);
180 	}
181 	if (retval == 0 && size == BUFFER_LENGTH)
182 		return 0;
183 	if (video_is_registered(&radio->vdev) && cmd != AMRADIO_GET_READY_FLAG)
184 		amradio_dev_warn(&radio->vdev.dev, "follow-up to cmd %02x failed\n", cmd);
185 	return retval ? retval : -EIO;
186 }
187 
188 /* switch on/off the radio. Send 8 bytes to device */
amradio_set_mute(struct amradio_device * radio,bool mute)189 static int amradio_set_mute(struct amradio_device *radio, bool mute)
190 {
191 	int ret = amradio_send_cmd(radio,
192 			AMRADIO_SET_MUTE, mute, NULL, 0, false);
193 
194 	if (!ret)
195 		radio->muted = mute;
196 	return ret;
197 }
198 
199 /* set a frequency, freq is defined by v4l's TUNER_LOW, i.e. 1/16th kHz */
amradio_set_freq(struct amradio_device * radio,int freq)200 static int amradio_set_freq(struct amradio_device *radio, int freq)
201 {
202 	unsigned short freq_send;
203 	u8 buf[3];
204 	int retval;
205 
206 	/* we need to be sure that frequency isn't out of range */
207 	freq = clamp_t(unsigned, freq, FREQ_MIN * FREQ_MUL, FREQ_MAX * FREQ_MUL);
208 	freq_send = 0x10 + (freq >> 3) / 25;
209 
210 	/* frequency is calculated from freq_send and placed in first 2 bytes */
211 	buf[0] = (freq_send >> 8) & 0xff;
212 	buf[1] = freq_send & 0xff;
213 	buf[2] = 0x01;
214 
215 	retval = amradio_send_cmd(radio, AMRADIO_SET_FREQ, 0, buf, 3, false);
216 	if (retval)
217 		return retval;
218 	radio->curfreq = freq;
219 	msleep(40);
220 	return 0;
221 }
222 
amradio_set_stereo(struct amradio_device * radio,bool stereo)223 static int amradio_set_stereo(struct amradio_device *radio, bool stereo)
224 {
225 	int ret = amradio_send_cmd(radio,
226 			AMRADIO_SET_MONO, !stereo, NULL, 0, false);
227 
228 	if (!ret)
229 		radio->stereo = stereo;
230 	return ret;
231 }
232 
amradio_get_stat(struct amradio_device * radio,bool * is_stereo,u32 * signal)233 static int amradio_get_stat(struct amradio_device *radio, bool *is_stereo, u32 *signal)
234 {
235 	int ret = amradio_send_cmd(radio,
236 			AMRADIO_GET_SIGNAL, 0, NULL, 0, true);
237 
238 	if (ret)
239 		return ret;
240 	*is_stereo = radio->buffer[2] >> 7;
241 	*signal = (radio->buffer[3] & 0xf0) << 8;
242 	return 0;
243 }
244 
245 /* Handle unplugging the device.
246  * We call video_unregister_device in any case.
247  * The last function called in this procedure is
248  * usb_amradio_device_release.
249  */
usb_amradio_disconnect(struct usb_interface * intf)250 static void usb_amradio_disconnect(struct usb_interface *intf)
251 {
252 	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
253 
254 	mutex_lock(&radio->lock);
255 	video_unregister_device(&radio->vdev);
256 	amradio_set_mute(radio, true);
257 	usb_set_intfdata(intf, NULL);
258 	v4l2_device_disconnect(&radio->v4l2_dev);
259 	mutex_unlock(&radio->lock);
260 	v4l2_device_put(&radio->v4l2_dev);
261 }
262 
263 /* vidioc_querycap - query device capabilities */
vidioc_querycap(struct file * file,void * priv,struct v4l2_capability * v)264 static int vidioc_querycap(struct file *file, void *priv,
265 					struct v4l2_capability *v)
266 {
267 	struct amradio_device *radio = video_drvdata(file);
268 
269 	strlcpy(v->driver, "radio-mr800", sizeof(v->driver));
270 	strlcpy(v->card, "AverMedia MR 800 USB FM Radio", sizeof(v->card));
271 	usb_make_path(radio->usbdev, v->bus_info, sizeof(v->bus_info));
272 	v->device_caps = V4L2_CAP_RADIO | V4L2_CAP_TUNER |
273 					V4L2_CAP_HW_FREQ_SEEK;
274 	v->capabilities = v->device_caps | V4L2_CAP_DEVICE_CAPS;
275 	return 0;
276 }
277 
278 /* vidioc_g_tuner - get tuner attributes */
vidioc_g_tuner(struct file * file,void * priv,struct v4l2_tuner * v)279 static int vidioc_g_tuner(struct file *file, void *priv,
280 				struct v4l2_tuner *v)
281 {
282 	struct amradio_device *radio = video_drvdata(file);
283 	bool is_stereo = false;
284 	int retval;
285 
286 	if (v->index > 0)
287 		return -EINVAL;
288 
289 	v->signal = 0;
290 	retval = amradio_get_stat(radio, &is_stereo, &v->signal);
291 	if (retval)
292 		return retval;
293 
294 	strcpy(v->name, "FM");
295 	v->type = V4L2_TUNER_RADIO;
296 	v->rangelow = FREQ_MIN * FREQ_MUL;
297 	v->rangehigh = FREQ_MAX * FREQ_MUL;
298 	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO |
299 		V4L2_TUNER_CAP_HWSEEK_WRAP;
300 	v->rxsubchans = is_stereo ? V4L2_TUNER_SUB_STEREO : V4L2_TUNER_SUB_MONO;
301 	v->audmode = radio->stereo ?
302 		V4L2_TUNER_MODE_STEREO : V4L2_TUNER_MODE_MONO;
303 	return 0;
304 }
305 
306 /* vidioc_s_tuner - set tuner attributes */
vidioc_s_tuner(struct file * file,void * priv,const struct v4l2_tuner * v)307 static int vidioc_s_tuner(struct file *file, void *priv,
308 				const struct v4l2_tuner *v)
309 {
310 	struct amradio_device *radio = video_drvdata(file);
311 
312 	if (v->index > 0)
313 		return -EINVAL;
314 
315 	/* mono/stereo selector */
316 	switch (v->audmode) {
317 	case V4L2_TUNER_MODE_MONO:
318 		return amradio_set_stereo(radio, WANT_MONO);
319 	default:
320 		return amradio_set_stereo(radio, WANT_STEREO);
321 	}
322 }
323 
324 /* vidioc_s_frequency - set tuner radio frequency */
vidioc_s_frequency(struct file * file,void * priv,const struct v4l2_frequency * f)325 static int vidioc_s_frequency(struct file *file, void *priv,
326 				const struct v4l2_frequency *f)
327 {
328 	struct amradio_device *radio = video_drvdata(file);
329 
330 	if (f->tuner != 0)
331 		return -EINVAL;
332 	return amradio_set_freq(radio, f->frequency);
333 }
334 
335 /* vidioc_g_frequency - get tuner radio frequency */
vidioc_g_frequency(struct file * file,void * priv,struct v4l2_frequency * f)336 static int vidioc_g_frequency(struct file *file, void *priv,
337 				struct v4l2_frequency *f)
338 {
339 	struct amradio_device *radio = video_drvdata(file);
340 
341 	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
342 		return -EINVAL;
343 	f->type = V4L2_TUNER_RADIO;
344 	f->frequency = radio->curfreq;
345 
346 	return 0;
347 }
348 
vidioc_s_hw_freq_seek(struct file * file,void * priv,const struct v4l2_hw_freq_seek * seek)349 static int vidioc_s_hw_freq_seek(struct file *file, void *priv,
350 		const struct v4l2_hw_freq_seek *seek)
351 {
352 	static u8 buf[8] = {
353 		0x3d, 0x32, 0x0f, 0x08, 0x3d, 0x32, 0x0f, 0x08
354 	};
355 	struct amradio_device *radio = video_drvdata(file);
356 	unsigned long timeout;
357 	int retval;
358 
359 	if (seek->tuner != 0 || !seek->wrap_around)
360 		return -EINVAL;
361 
362 	if (file->f_flags & O_NONBLOCK)
363 		return -EWOULDBLOCK;
364 
365 	retval = amradio_send_cmd(radio,
366 			AMRADIO_SET_SEARCH_LVL, 0, buf, 8, false);
367 	if (retval)
368 		return retval;
369 	amradio_set_freq(radio, radio->curfreq);
370 	retval = amradio_send_cmd(radio,
371 		seek->seek_upward ? AMRADIO_SET_SEARCH_UP : AMRADIO_SET_SEARCH_DOWN,
372 		0, NULL, 0, false);
373 	if (retval)
374 		return retval;
375 	timeout = jiffies + msecs_to_jiffies(30000);
376 	for (;;) {
377 		if (time_after(jiffies, timeout)) {
378 			retval = -ENODATA;
379 			break;
380 		}
381 		if (schedule_timeout_interruptible(msecs_to_jiffies(10))) {
382 			retval = -ERESTARTSYS;
383 			break;
384 		}
385 		retval = amradio_send_cmd(radio, AMRADIO_GET_READY_FLAG,
386 				0, NULL, 0, true);
387 		if (retval)
388 			continue;
389 		amradio_send_cmd(radio, AMRADIO_GET_FREQ, 0, NULL, 0, true);
390 		if (radio->buffer[1] || radio->buffer[2]) {
391 			/* To check: sometimes radio->curfreq is set to out of range value */
392 			radio->curfreq = (radio->buffer[1] << 8) | radio->buffer[2];
393 			radio->curfreq = (radio->curfreq - 0x10) * 200;
394 			amradio_send_cmd(radio, AMRADIO_STOP_SEARCH,
395 					0, NULL, 0, false);
396 			amradio_set_freq(radio, radio->curfreq);
397 			retval = 0;
398 			break;
399 		}
400 	}
401 	amradio_send_cmd(radio, AMRADIO_STOP_SEARCH, 0, NULL, 0, false);
402 	amradio_set_freq(radio, radio->curfreq);
403 	return retval;
404 }
405 
usb_amradio_s_ctrl(struct v4l2_ctrl * ctrl)406 static int usb_amradio_s_ctrl(struct v4l2_ctrl *ctrl)
407 {
408 	struct amradio_device *radio =
409 		container_of(ctrl->handler, struct amradio_device, hdl);
410 
411 	switch (ctrl->id) {
412 	case V4L2_CID_AUDIO_MUTE:
413 		return amradio_set_mute(radio, ctrl->val);
414 	}
415 
416 	return -EINVAL;
417 }
418 
usb_amradio_init(struct amradio_device * radio)419 static int usb_amradio_init(struct amradio_device *radio)
420 {
421 	int retval;
422 
423 	retval = amradio_set_mute(radio, true);
424 	if (retval)
425 		goto out_err;
426 	retval = amradio_set_stereo(radio, true);
427 	if (retval)
428 		goto out_err;
429 	retval = amradio_set_freq(radio, radio->curfreq);
430 	if (retval)
431 		goto out_err;
432 	return 0;
433 
434 out_err:
435 	amradio_dev_err(&radio->vdev.dev, "initialization failed\n");
436 	return retval;
437 }
438 
439 /* Suspend device - stop device. Need to be checked and fixed */
usb_amradio_suspend(struct usb_interface * intf,pm_message_t message)440 static int usb_amradio_suspend(struct usb_interface *intf, pm_message_t message)
441 {
442 	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
443 
444 	mutex_lock(&radio->lock);
445 	if (!radio->muted) {
446 		amradio_set_mute(radio, true);
447 		radio->muted = false;
448 	}
449 	mutex_unlock(&radio->lock);
450 
451 	dev_info(&intf->dev, "going into suspend..\n");
452 	return 0;
453 }
454 
455 /* Resume device - start device. Need to be checked and fixed */
usb_amradio_resume(struct usb_interface * intf)456 static int usb_amradio_resume(struct usb_interface *intf)
457 {
458 	struct amradio_device *radio = to_amradio_dev(usb_get_intfdata(intf));
459 
460 	mutex_lock(&radio->lock);
461 	amradio_set_stereo(radio, radio->stereo);
462 	amradio_set_freq(radio, radio->curfreq);
463 
464 	if (!radio->muted)
465 		amradio_set_mute(radio, false);
466 
467 	mutex_unlock(&radio->lock);
468 
469 	dev_info(&intf->dev, "coming out of suspend..\n");
470 	return 0;
471 }
472 
473 static const struct v4l2_ctrl_ops usb_amradio_ctrl_ops = {
474 	.s_ctrl = usb_amradio_s_ctrl,
475 };
476 
477 /* File system interface */
478 static const struct v4l2_file_operations usb_amradio_fops = {
479 	.owner		= THIS_MODULE,
480 	.open		= v4l2_fh_open,
481 	.release	= v4l2_fh_release,
482 	.poll		= v4l2_ctrl_poll,
483 	.unlocked_ioctl	= video_ioctl2,
484 };
485 
486 static const struct v4l2_ioctl_ops usb_amradio_ioctl_ops = {
487 	.vidioc_querycap    = vidioc_querycap,
488 	.vidioc_g_tuner     = vidioc_g_tuner,
489 	.vidioc_s_tuner     = vidioc_s_tuner,
490 	.vidioc_g_frequency = vidioc_g_frequency,
491 	.vidioc_s_frequency = vidioc_s_frequency,
492 	.vidioc_s_hw_freq_seek = vidioc_s_hw_freq_seek,
493 	.vidioc_log_status  = v4l2_ctrl_log_status,
494 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
495 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
496 };
497 
usb_amradio_release(struct v4l2_device * v4l2_dev)498 static void usb_amradio_release(struct v4l2_device *v4l2_dev)
499 {
500 	struct amradio_device *radio = to_amradio_dev(v4l2_dev);
501 
502 	/* free rest memory */
503 	v4l2_ctrl_handler_free(&radio->hdl);
504 	v4l2_device_unregister(&radio->v4l2_dev);
505 	kfree(radio->buffer);
506 	kfree(radio);
507 }
508 
509 /* check if the device is present and register with v4l and usb if it is */
usb_amradio_probe(struct usb_interface * intf,const struct usb_device_id * id)510 static int usb_amradio_probe(struct usb_interface *intf,
511 				const struct usb_device_id *id)
512 {
513 	struct amradio_device *radio;
514 	int retval;
515 
516 	radio = kzalloc(sizeof(struct amradio_device), GFP_KERNEL);
517 
518 	if (!radio) {
519 		dev_err(&intf->dev, "kmalloc for amradio_device failed\n");
520 		retval = -ENOMEM;
521 		goto err;
522 	}
523 
524 	radio->buffer = kmalloc(BUFFER_LENGTH, GFP_KERNEL);
525 
526 	if (!radio->buffer) {
527 		dev_err(&intf->dev, "kmalloc for radio->buffer failed\n");
528 		retval = -ENOMEM;
529 		goto err_nobuf;
530 	}
531 
532 	retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
533 	if (retval < 0) {
534 		dev_err(&intf->dev, "couldn't register v4l2_device\n");
535 		goto err_v4l2;
536 	}
537 
538 	v4l2_ctrl_handler_init(&radio->hdl, 1);
539 	v4l2_ctrl_new_std(&radio->hdl, &usb_amradio_ctrl_ops,
540 			  V4L2_CID_AUDIO_MUTE, 0, 1, 1, 1);
541 	if (radio->hdl.error) {
542 		retval = radio->hdl.error;
543 		dev_err(&intf->dev, "couldn't register control\n");
544 		goto err_ctrl;
545 	}
546 	mutex_init(&radio->lock);
547 
548 	radio->v4l2_dev.ctrl_handler = &radio->hdl;
549 	radio->v4l2_dev.release = usb_amradio_release;
550 	strlcpy(radio->vdev.name, radio->v4l2_dev.name,
551 		sizeof(radio->vdev.name));
552 	radio->vdev.v4l2_dev = &radio->v4l2_dev;
553 	radio->vdev.fops = &usb_amradio_fops;
554 	radio->vdev.ioctl_ops = &usb_amradio_ioctl_ops;
555 	radio->vdev.release = video_device_release_empty;
556 	radio->vdev.lock = &radio->lock;
557 
558 	radio->usbdev = interface_to_usbdev(intf);
559 	radio->intf = intf;
560 	usb_set_intfdata(intf, &radio->v4l2_dev);
561 	radio->curfreq = 95.16 * FREQ_MUL;
562 
563 	video_set_drvdata(&radio->vdev, radio);
564 	retval = usb_amradio_init(radio);
565 	if (retval)
566 		goto err_vdev;
567 
568 	retval = video_register_device(&radio->vdev, VFL_TYPE_RADIO,
569 					radio_nr);
570 	if (retval < 0) {
571 		dev_err(&intf->dev, "could not register video device\n");
572 		goto err_vdev;
573 	}
574 
575 	return 0;
576 
577 err_vdev:
578 	v4l2_ctrl_handler_free(&radio->hdl);
579 err_ctrl:
580 	v4l2_device_unregister(&radio->v4l2_dev);
581 err_v4l2:
582 	kfree(radio->buffer);
583 err_nobuf:
584 	kfree(radio);
585 err:
586 	return retval;
587 }
588 
589 /* USB Device ID List */
590 static const struct usb_device_id usb_amradio_device_table[] = {
591 	{ USB_DEVICE_AND_INTERFACE_INFO(USB_AMRADIO_VENDOR, USB_AMRADIO_PRODUCT,
592 							USB_CLASS_HID, 0, 0) },
593 	{ }						/* Terminating entry */
594 };
595 
596 MODULE_DEVICE_TABLE(usb, usb_amradio_device_table);
597 
598 /* USB subsystem interface */
599 static struct usb_driver usb_amradio_driver = {
600 	.name			= MR800_DRIVER_NAME,
601 	.probe			= usb_amradio_probe,
602 	.disconnect		= usb_amradio_disconnect,
603 	.suspend		= usb_amradio_suspend,
604 	.resume			= usb_amradio_resume,
605 	.reset_resume		= usb_amradio_resume,
606 	.id_table		= usb_amradio_device_table,
607 };
608 
609 module_usb_driver(usb_amradio_driver);
610