aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/radio/radio-gemtek.c
blob: 36ce0611c0379824d7d2b792611a2acfb7c20cf8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
/* GemTek radio card driver for Linux (C) 1998 Jonas Munsin <jmunsin@iki.fi>
 *
 * GemTek hasn't released any specs on the card, so the protocol had to
 * be reverse engineered with dosemu.
 *
 * Besides the protocol changes, this is mostly a copy of:
 *
 *    RadioTrack II driver for Linux radio support (C) 1998 Ben Pfaff
 *
 *    Based on RadioTrack I/RadioReveal (C) 1997 M. Kirkwood
 *    Converted to new API by Alan Cox <alan@lxorguk.ukuu.org.uk>
 *    Various bugfixes and enhancements by Russell Kroll <rkroll@exploits.org>
 *
 * TODO: Allow for more than one of these foolish entities :-)
 *
 * Converted to V4L2 API by Mauro Carvalho Chehab <mchehab@infradead.org>
 */

#include <linux/module.h>	/* Modules 			*/
#include <linux/init.h>		/* Initdata			*/
#include <linux/ioport.h>	/* request_region		*/
#include <linux/delay.h>	/* udelay			*/
#include <linux/videodev2.h>	/* kernel radio structs		*/
#include <linux/mutex.h>
#include <linux/io.h>		/* outb, outb_p			*/
#include <media/v4l2-ioctl.h>
#include <media/v4l2-device.h>

/*
 * Module info.
 */

MODULE_AUTHOR("Jonas Munsin, Pekka Seppänen <pexu@kapsi.fi>");
MODULE_DESCRIPTION("A driver for the GemTek Radio card.");
MODULE_LICENSE("GPL");
MODULE_VERSION("0.0.4");

/*
 * Module params.
 */

#ifndef CONFIG_RADIO_GEMTEK_PORT
#define CONFIG_RADIO_GEMTEK_PORT -1
#endif
#ifndef CONFIG_RADIO_GEMTEK_PROBE
#define CONFIG_RADIO_GEMTEK_PROBE 1
#endif

static int io		= CONFIG_RADIO_GEMTEK_PORT;
static bool probe	= CONFIG_RADIO_GEMTEK_PROBE;
static bool hardmute;
static bool shutdown	= 1;
static bool keepmuted	= 1;
static bool initmute	= 1;
static int radio_nr	= -1;

module_param(io, int, 0444);
MODULE_PARM_DESC(io, "Force I/O port for the GemTek Radio card if automatic "
	 "probing is disabled or fails. The most common I/O ports are: 0x20c "
	 "0x30c, 0x24c or 0x34c (0x20c, 0x248 and 0x28c have been reported to "
	 "work for the combined sound/radiocard).");

module_param(probe, bool, 0444);
MODULE_PARM_DESC(probe, "Enable automatic device probing. Note: only the most "
	"common I/O ports used by the card are probed.");

module_param(hardmute, bool, 0644);
MODULE_PARM_DESC(hardmute, "Enable `hard muting' by shutting down PLL, may "
	 "reduce static noise.");

module_param(shutdown, bool, 0644);
MODULE_PARM_DESC(shutdown, "Enable shutting down PLL and muting line when "
	 "module is unloaded.");

module_param(keepmuted, bool, 0644);
MODULE_PARM_DESC(keepmuted, "Keep card muted even when frequency is changed.");

module_param(initmute, bool, 0444);
MODULE_PARM_DESC(initmute, "Mute card when module is loaded.");

module_param(radio_nr, int, 0444);

/*
 * Functions for controlling the card.
 */
#define GEMTEK_LOWFREQ	(87*16000)
#define GEMTEK_HIGHFREQ	(108*16000)

/*
 * Frequency calculation constants.  Intermediate frequency 10.52 MHz (nominal
 * value 10.7 MHz), reference divisor 6.39 kHz (nominal 6.25 kHz).
 */
#define FSCALE		8
#define IF_OFFSET	((unsigned int)(10.52 * 16000 * (1<<FSCALE)))
#define REF_FREQ	((unsigned int)(6.39 * 16 * (1<<FSCALE)))

#define GEMTEK_CK		0x01	/* Clock signal			*/
#define GEMTEK_DA		0x02	/* Serial data			*/
#define GEMTEK_CE		0x04	/* Chip enable			*/
#define GEMTEK_NS		0x08	/* No signal			*/
#define GEMTEK_MT		0x10	/* Line mute			*/
#define GEMTEK_STDF_3_125_KHZ	0x01	/* Standard frequency 3.125 kHz	*/
#define GEMTEK_PLL_OFF		0x07	/* PLL off			*/

#define BU2614_BUS_SIZE	32	/* BU2614 / BU2614FS bus size		*/

#define SHORT_DELAY 5		/* usec */
#define LONG_DELAY 75		/* usec */

struct gemtek {
	struct v4l2_device v4l2_dev;
	struct video_device vdev;
	struct mutex lock;
	unsigned long lastfreq;
	int muted;
	int verified;
	int io;
	u32 bu2614data;
};

static struct gemtek gemtek_card;

#define BU2614_FREQ_BITS 	16 /* D0..D15, Frequency data		*/
#define BU2614_PORT_BITS	3 /* P0..P2, Output port control data	*/
#define BU2614_VOID_BITS	4 /* unused 				*/
#define BU2614_FMES_BITS	1 /* CT, Frequency measurement beginning data */
#define BU2614_STDF_BITS	3 /* R0..R2, Standard frequency data	*/
#define BU2614_SWIN_BITS	1 /* S, Switch between FMIN / AMIN	*/
#define BU2614_SWAL_BITS        1 /* PS, Swallow counter division (AMIN only)*/
#define BU2614_VOID2_BITS	1 /* unused				*/
#define BU2614_FMUN_BITS	1 /* GT, Frequency measurement time & unlock */
#define BU2614_TEST_BITS	1 /* TS, Test data is input		*/

#define BU2614_FREQ_SHIFT 	0
#define BU2614_PORT_SHIFT	(BU2614_FREQ_BITS + BU2614_FREQ_SHIFT)
#define BU2614_VOID_SHIFT	(BU2614_PORT_BITS + BU2614_PORT_SHIFT)
#define BU2614_FMES_SHIFT	(BU2614_VOID_BITS + BU2614_VOID_SHIFT)
#define BU2614_STDF_SHIFT	(BU2614_FMES_BITS + BU2614_FMES_SHIFT)
#define BU2614_SWIN_SHIFT	(BU2614_STDF_BITS + BU2614_STDF_SHIFT)
#define BU2614_SWAL_SHIFT	(BU2614_SWIN_BITS + BU2614_SWIN_SHIFT)
#define BU2614_VOID2_SHIFT	(BU2614_SWAL_BITS + BU2614_SWAL_SHIFT)
#define BU2614_FMUN_SHIFT	(BU2614_VOID2_BITS + BU2614_VOID2_SHIFT)
#define BU2614_TEST_SHIFT	(BU2614_FMUN_BITS + BU2614_FMUN_SHIFT)

#define MKMASK(field)	(((1<<BU2614_##field##_BITS) - 1) << \
			BU2614_##field##_SHIFT)
#define BU2614_PORT_MASK	MKMASK(PORT)
#define BU2614_FREQ_MASK	MKMASK(FREQ)
#define BU2614_VOID_MASK	MKMASK(VOID)
#define BU2614_FMES_MASK	MKMASK(FMES)
#define BU2614_STDF_MASK	MKMASK(STDF)
#define BU2614_SWIN_MASK	MKMASK(SWIN)
#define BU2614_SWAL_MASK	MKMASK(SWAL)
#define BU2614_VOID2_MASK	MKMASK(VOID2)
#define BU2614_FMUN_MASK	MKMASK(FMUN)
#define BU2614_TEST_MASK	MKMASK(TEST)

/*
 * Set data which will be sent to BU2614FS.
 */
#define gemtek_bu2614_set(dev, field, data) ((dev)->bu2614data = \
	((dev)->bu2614data & ~field##_MASK) | ((data) << field##_SHIFT))

/*
 * Transmit settings to BU2614FS over GemTek IC.
 */
static void gemtek_bu2614_transmit(struct gemtek *gt)
{
	int i, bit, q, mute;

	mutex_lock(&gt->lock);

	mute = gt->muted ? GEMTEK_MT : 0x00;

	outb_p(mute | GEMTEK_DA | GEMTEK_CK, gt->io);
	udelay(SHORT_DELAY);
	outb_p(mute | GEMTEK_CE | GEMTEK_DA | GEMTEK_CK, gt->io);
	udelay(LONG_DELAY);

	for (i = 0, q = gt->bu2614data; i < 32; i++, q >>= 1) {
		bit = (q & 1) ? GEMTEK_DA : 0;
		outb_p(mute | GEMTEK_CE | bit, gt->io);
		udelay(SHORT_DELAY);
		outb_p(mute | GEMTEK_CE | bit | GEMTEK_CK, gt->io);
		udelay(SHORT_DELAY);
	}

	outb_p(mute | GEMTEK_DA | GEMTEK_CK, gt->io);
	udelay(SHORT_DELAY);
	outb_p(mute | GEMTEK_CE | GEMTEK_DA | GEMTEK_CK, gt->io);
	udelay(LONG_DELAY);

	mutex_unlock(&gt->lock);
}

/*
 * Calculate divisor from FM-frequency for BU2614FS (3.125 KHz STDF expected).
 */
static unsigned long gemtek_convfreq(unsigned long freq)
{
	return ((freq<<FSCALE) + IF_OFFSET + REF_FREQ/2) / REF_FREQ;
}

/*
 * Set FM-frequency.
 */
static void gemtek_setfreq(struct gemtek *gt, unsigned long freq)
{
	if (keepmuted && hardmute && gt->muted)
		return;

	freq = clamp_val(freq, GEMTEK_LOWFREQ, GEMTEK_HIGHFREQ);

	gt->lastfreq = freq;
	gt->muted = 0;

	gemtek_bu2614_set(gt, BU2614_PORT, 0);
	gemtek_bu2614_set(gt, BU2614_FMES, 0);
	gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
	gemtek_bu2614_set(gt, BU2614_SWAL, 0);
	gemtek_bu2614_set(gt, BU2614_FMUN, 1);	/* GT bit set	*/
	gemtek_bu2614_set(gt, BU2614_TEST, 0);

	gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_STDF_3_125_KHZ);
	gemtek_bu2614_set(gt, BU2614_FREQ, gemtek_convfreq(freq));

	gemtek_bu2614_transmit(gt);
}

/*
 * Set mute flag.
 */
static void gemtek_mute(struct gemtek *gt)
{
	int i;

	gt->muted = 1;

	if (hardmute) {
		/* Turn off PLL, disable data output */
		gemtek_bu2614_set(gt, BU2614_PORT, 0);
		gemtek_bu2614_set(gt, BU2614_FMES, 0);	/* CT bit off	*/
		gemtek_bu2614_set(gt, BU2614_SWIN, 0);	/* FM-mode	*/
		gemtek_bu2614_set(gt, BU2614_SWAL, 0);
		gemtek_bu2614_set(gt, BU2614_FMUN, 0);	/* GT bit off	*/
		gemtek_bu2614_set(gt, BU2614_TEST, 0);
		gemtek_bu2614_set(gt, BU2614_STDF, GEMTEK_PLL_OFF);
		gemtek_bu2614_set(gt, BU2614_FREQ, 0);
		gemtek_bu2614_transmit(gt);
		return;
	}

	mutex_lock(&gt->lock);

	/* Read bus contents (CE, CK and DA). */
	i = inb_p(gt->io);
	/* Write it back with mute flag set. */
	outb_p((i >> 5) | GEMTEK_MT, gt->io);
	udelay(SHORT_DELAY);

	mutex_unlock(&gt->lock);
}

/*
 * Unset mute flag.
 */
static void gemtek_unmute(struct gemtek *gt)
{
	int i;

	gt->muted = 0;
	if (hardmute) {
		/* Turn PLL back on. */
		gemtek_setfreq(gt, gt->lastfreq);
		return;
	}
	mutex_lock(&gt->lock);

	i = inb_p(gt->io);
	outb_p(i >> 5, gt->io);
	udelay(SHORT_DELAY);

	mutex_unlock(&gt->lock);
}

/*
 * Get signal strength (= stereo status).
 */
static inline int gemtek_getsigstr(struct gemtek *gt)
{
	int sig;

	mutex_lock(&gt->lock);
	sig = inb_p(gt->io) & GEMTEK_NS ? 0 : 1;
	mutex_unlock(&gt->lock);
	return sig;
}

/*
 * Check if requested card acts like GemTek Radio card.
 */
static int gemtek_verify(struct gemtek *gt, int port)
{
	int i, q;

	if (gt->verified == port)
		return 1;

	mutex_lock(&gt->lock);

	q = inb_p(port);	/* Read bus contents before probing. */
	/* Try to turn on CE, CK and DA respectively and check if card responds
	   properly. */
	for (i = 0; i < 3; ++i) {
		outb_p(1 << i, port);
		udelay(SHORT_DELAY);

		if ((inb_p(port) & (~GEMTEK_NS)) != (0x17 | (1 << (i + 5)))) {
			mutex_unlock(&gt->lock);
			return 0;
		}
	}
	outb_p(q >> 5, port);	/* Write bus contents back. */
	udelay(SHORT_DELAY);

	mutex_unlock(&gt->lock);
	gt->verified = port;

	return 1;
}

/*
 * Automatic probing for card.
 */
static int gemtek_probe(struct gemtek *gt)
{
	struct v4l2_device *v4l2_dev = &gt->v4l2_dev;
	int ioports[] = { 0x20c, 0x30c, 0x24c, 0x34c, 0x248, 0x28c };
	int i;

	if (!probe) {
		v4l2_info(v4l2_dev, "Automatic device probing disabled.\n");
		return -1;
	}

	v4l2_info(v4l2_dev, "Automatic device probing enabled.\n");

	for (i = 0; i < ARRAY_SIZE(ioports); ++i) {
		v4l2_info(v4l2_dev, "Trying I/O port 0x%x...\n", ioports[i]);

		if (!request_region(ioports[i], 1, "gemtek-probe")) {
			v4l2_warn(v4l2_dev, "I/O port 0x%x busy!\n",
			       ioports[i]);
			continue;
		}

		if (gemtek_verify(gt, ioports[i])) {
			v4l2_info(v4l2_dev, "Card found from I/O port "
			       "0x%x!\n", ioports[i]);

			release_region(ioports[i], 1);
			gt->io = ioports[i];
			return gt->io;
		}

		release_region(ioports[i], 1);
	}

	v4l2_err(v4l2_dev, "Automatic probing failed!\n");
	return -1;
}

/*
 * Video 4 Linux stuff.
 */

static const struct v4l2_file_operations gemtek_fops = {
	.owner		= THIS_MODULE,
	.unlocked_ioctl	= video_ioctl2,
};

static int vidioc_querycap(struct file *file, void *priv,
			   struct v4l2_capability *v)
{
	strlcpy(v->driver, "radio-gemtek", sizeof(v->driver));
	strlcpy(v->card, "GemTek", sizeof(v->card));
	strlcpy(v->bus_info, "ISA", sizeof(v->bus_info));
	v->capabilities = V4L2_CAP_TUNER | V4L2_CAP_RADIO;
	return 0;
}

static int vidioc_g_tuner(struct file *file, void *priv, struct v4l2_tuner *v)
{
	struct gemtek *gt = video_drvdata(file);

	if (v->index > 0)
		return -EINVAL;

	strlcpy(v->name, "FM", sizeof(v->name));
	v->type = V4L2_TUNER_RADIO;
	v->rangelow = GEMTEK_LOWFREQ;
	v->rangehigh = GEMTEK_HIGHFREQ;
	v->capability = V4L2_TUNER_CAP_LOW | V4L2_TUNER_CAP_STEREO;
	v->signal = 0xffff * gemtek_getsigstr(gt);
	if (v->signal) {
		v->audmode = V4L2_TUNER_MODE_STEREO;
		v->rxsubchans = V4L2_TUNER_SUB_STEREO;
	} else {
		v->audmode = V4L2_TUNER_MODE_MONO;
		v->rxsubchans = V4L2_TUNER_SUB_MONO;
	}
	return 0;
}

static int vidioc_s_tuner(struct file *file, void *priv, struct v4l2_tuner *v)
{
	return (v->index != 0) ? -EINVAL : 0;
}

static int vidioc_g_frequency(struct file *file, void *priv,
			      struct v4l2_frequency *f)
{
	struct gemtek *gt = video_drvdata(file);

	if (f->tuner != 0)
		return -EINVAL;
	f->type = V4L2_TUNER_RADIO;
	f->frequency = gt->lastfreq;
	return 0;
}

static int vidioc_s_frequency(struct file *file, void *priv,
			      struct v4l2_frequency *f)
{
	struct gemtek *gt = video_drvdata(file);

	if (f->tuner != 0 || f->type != V4L2_TUNER_RADIO)
		return -EINVAL;
	gemtek_setfreq(gt, f->frequency);
	return 0;
}

static int vidioc_queryctrl(struct file *file, void *priv,
			    struct v4l2_queryctrl *qc)
{
	switch (qc->id) {
	case V4L2_CID_AUDIO_MUTE:
		return v4l2_ctrl_query_fill(qc, 0, 1, 1, 0);
	default:
		return -EINVAL;
	}
}

static int vidioc_g_ctrl(struct file *file, void *priv,
			 struct v4l2_control *ctrl)
{
	struct gemtek *gt = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		ctrl->value = gt->muted;
		return 0;
	}
	return -EINVAL;
}

static int vidioc_s_ctrl(struct file *file, void *priv,
			 struct v4l2_control *ctrl)
{
	struct gemtek *gt = video_drvdata(file);

	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		if (ctrl->value)
			gemtek_mute(gt);
		else
			gemtek_unmute(gt);
		return 0;
	}
	return -EINVAL;
}

static int vidioc_g_input(struct file *filp, void *priv, unsigned int *i)
{
	*i = 0;
	return 0;
}

static int vidioc_s_input(struct file *filp, void *priv, unsigned int i)
{
	return (i != 0) ? -EINVAL : 0;
}

static int vidioc_g_audio(struct file *file, void *priv, struct v4l2_audio *a)
{
	a->index = 0;
	strlcpy(a->name, "Radio", sizeof(a->name));
	a->capability = V4L2_AUDCAP_STEREO;
	return 0;
}

static int vidioc_s_audio(struct file *file, void *priv, struct v4l2_audio *a)
{
	return (a->index != 0) ? -EINVAL : 0;
}

static const struct v4l2_ioctl_ops gemtek_ioctl_ops = {
	.vidioc_querycap	= vidioc_querycap,
	.vidioc_g_tuner		= vidioc_g_tuner,
	.vidioc_s_tuner		= vidioc_s_tuner,
	.vidioc_g_audio		= vidioc_g_audio,
	.vidioc_s_audio		= vidioc_s_audio,
	.vidioc_g_input		= vidioc_g_input,
	.vidioc_s_input		= vidioc_s_input,
	.vidioc_g_frequency	= vidioc_g_frequency,
	.vidioc_s_frequency	= vidioc_s_frequency,
	.vidioc_queryctrl	= vidioc_queryctrl,
	.vidioc_g_ctrl		= vidioc_g_ctrl,
	.vidioc_s_ctrl		= vidioc_s_ctrl
};

/*
 * Initialization / cleanup related stuff.
 */

static int __init gemtek_init(void)
{
	struct gemtek *gt = &gemtek_card;
	struct v4l2_device *v4l2_dev = &gt->v4l2_dev;
	int res;

	strlcpy(v4l2_dev->name, "gemtek", sizeof(v4l2_dev->name));

	v4l2_info(v4l2_dev, "GemTek Radio card driver: v0.0.3\n");

	mutex_init(&gt->lock);

	gt->verified = -1;
	gt->io = io;
	gemtek_probe(gt);
	if (gt->io) {
		if (!request_region(gt->io, 1, "gemtek")) {
			v4l2_err(v4l2_dev, "I/O port 0x%x already in use.\n", gt->io);
			return -EBUSY;
		}

		if (!gemtek_verify(gt, gt->io))
			v4l2_warn(v4l2_dev, "Card at I/O port 0x%x does not "
			       "respond properly, check your "
			       "configuration.\n", gt->io);
		else
			v4l2_info(v4l2_dev, "Using I/O port 0x%x.\n", gt->io);
	} else if (probe) {
		v4l2_err(v4l2_dev, "Automatic probing failed and no "
		       "fixed I/O port defined.\n");
		return -ENODEV;
	} else {
		v4l2_err(v4l2_dev, "Automatic probing disabled but no fixed "
		       "I/O port defined.");
		return -EINVAL;
	}

	res = v4l2_device_register(NULL, v4l2_dev);
	if (res < 0) {
		v4l2_err(v4l2_dev, "Could not register v4l2_device\n");
		release_region(gt->io, 1);
		return res;
	}

	strlcpy(gt->vdev.name, v4l2_dev->name, sizeof(gt->vdev.name));
	gt->vdev.v4l2_dev = v4l2_dev;
	gt->vdev.fops = &gemtek_fops;
	gt->vdev.ioctl_ops = &gemtek_ioctl_ops;
	gt->vdev.release = video_device_release_empty;
	video_set_drvdata(&gt->vdev, gt);

	/* Set defaults */
	gt->lastfreq = GEMTEK_LOWFREQ;
	gt->bu2614data = 0;

	if (initmute)
		gemtek_mute(gt);

	if (video_register_device(&gt->vdev, VFL_TYPE_RADIO, radio_nr) < 0) {
		v4l2_device_unregister(v4l2_dev);
		release_region(gt->io, 1);
		return -EBUSY;
	}

	return 0;
}

/*
 * Module cleanup
 */
static void __exit gemtek_exit(void)
{
	struct gemtek *gt = &gemtek_card;
	struct v4l2_device *v4l2_dev = &gt->v4l2_dev;

	if (shutdown) {
		hardmute = 1;	/* Turn off PLL */
		gemtek_mute(gt);
	} else {
		v4l2_info(v4l2_dev, "Module unloaded but card not muted!\n");
	}

	video_unregister_device(&gt->vdev);
	v4l2_device_unregister(&gt->v4l2_dev);
	release_region(gt->io, 1);
}

module_init(gemtek_init);
module_exit(gemtek_exit);