aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/video/saa5249.c
blob: 6ef3affb97f163d165c227a178c199ea5913d7bc (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
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
/*
 * Modified in order to keep it compatible both with new and old videotext IOCTLs by
 * Michael Geng <linux@MichaelGeng.de>
 *
 *	Cleaned up to use existing videodev interface and allow the idea
 *	of multiple teletext decoders on the video4linux iface. Changed i2c
 *	to cover addressing clashes on device busses. It's also rebuilt so
 *	you can add arbitary multiple teletext devices to Linux video4linux
 *	now (well 32 anyway).
 *
 *	Alan Cox <alan@lxorguk.ukuu.org.uk>
 *
 *	The original driver was heavily modified to match the i2c interface
 *	It was truncated to use the WinTV boards, too.
 *
 *	Copyright (c) 1998 Richard Guenther <richard.guenther@student.uni-tuebingen.de>
 *
 *	Derived From
 *
 * vtx.c:
 * This is a loadable character-device-driver for videotext-interfaces
 * (aka teletext). Please check the Makefile/README for a list of supported
 * interfaces.
 *
 * Copyright (c) 1994-97 Martin Buck  <martin-2.buck@student.uni-ulm.de>
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
 * USA.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/smp_lock.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/videotext.h>
#include <linux/videodev.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-i2c-drv-legacy.h>

MODULE_AUTHOR("Michael Geng <linux@MichaelGeng.de>");
MODULE_DESCRIPTION("Philips SAA5249 Teletext decoder driver");
MODULE_LICENSE("GPL");

#define VTX_VER_MAJ 1
#define VTX_VER_MIN 8


#define NUM_DAUS 4
#define NUM_BUFS 8

static const int disp_modes[8][3] =
{
	{ 0x46, 0x03, 0x03 },	/* DISPOFF */
	{ 0x46, 0xcc, 0xcc },	/* DISPNORM */
	{ 0x44, 0x0f, 0x0f },	/* DISPTRANS */
	{ 0x46, 0xcc, 0x46 },	/* DISPINS */
	{ 0x44, 0x03, 0x03 },	/* DISPOFF, interlaced */
	{ 0x44, 0xcc, 0xcc },	/* DISPNORM, interlaced */
	{ 0x44, 0x0f, 0x0f },	/* DISPTRANS, interlaced */
	{ 0x44, 0xcc, 0x46 }	/* DISPINS, interlaced */
};



#define PAGE_WAIT    msecs_to_jiffies(300)	/* Time between requesting page and */
						/* checking status bits */
#define PGBUF_EXPIRE msecs_to_jiffies(15000)	/* Time to wait before retransmitting */
						/* page regardless of infobits */
typedef struct {
	u8 pgbuf[VTX_VIRTUALSIZE];		/* Page-buffer */
	u8 laststat[10];			/* Last value of infobits for DAU */
	u8 sregs[7];				/* Page-request registers */
	unsigned long expire;			/* Time when page will be expired */
	unsigned clrfound : 1;			/* VTXIOCCLRFOUND has been called */
	unsigned stopped : 1;			/* VTXIOCSTOPDAU has been called */
} vdau_t;

struct saa5249_device
{
	vdau_t vdau[NUM_DAUS];			/* Data for virtual DAUs (the 5249 only has one */
						/* real DAU, so we have to simulate some more) */
	int vtx_use_count;
	int is_searching[NUM_DAUS];
	int disp_mode;
	int virtual_mode;
	struct i2c_client *client;
	unsigned long in_use;
	struct mutex lock;
};


#define CCTWR 34		/* I�C write/read-address of vtx-chip */
#define CCTRD 35
#define NOACK_REPEAT 10		/* Retry access this many times on failure */
#define CLEAR_DELAY   msecs_to_jiffies(50)	/* Time required to clear a page */
#define READY_TIMEOUT msecs_to_jiffies(30)	/* Time to wait for ready signal of I2C-bus interface */
#define INIT_DELAY 500		/* Time in usec to wait at initialization of CEA interface */
#define START_DELAY 10		/* Time in usec to wait before starting write-cycle (CEA) */

#define VTX_DEV_MINOR 0

static struct video_device saa_template;	/* Declared near bottom */

/*
 *	Wait the given number of jiffies (10ms). This calls the scheduler, so the actual
 *	delay may be longer.
 */

static void jdelay(unsigned long delay)
{
	sigset_t oldblocked = current->blocked;

	spin_lock_irq(&current->sighand->siglock);
	sigfillset(&current->blocked);
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
	msleep_interruptible(jiffies_to_msecs(delay));

	spin_lock_irq(&current->sighand->siglock);
	current->blocked = oldblocked;
	recalc_sigpending();
	spin_unlock_irq(&current->sighand->siglock);
}


/*
 *	I2C interfaces
 */

static int i2c_sendbuf(struct saa5249_device *t, int reg, int count, u8 *data)
{
	char buf[64];

	buf[0] = reg;
	memcpy(buf+1, data, count);

	if (i2c_master_send(t->client, buf, count + 1) == count + 1)
		return 0;
	return -1;
}

static int i2c_senddata(struct saa5249_device *t, ...)
{
	unsigned char buf[64];
	int v;
	int ct = 0;
	va_list argp;
	va_start(argp,t);

	while ((v = va_arg(argp, int)) != -1)
		buf[ct++] = v;

	va_end(argp);
	return i2c_sendbuf(t, buf[0], ct-1, buf+1);
}

/* Get count number of bytes from I²C-device at address adr, store them in buf. Start & stop
 * handshaking is done by this routine, ack will be sent after the last byte to inhibit further
 * sending of data. If uaccess is 'true', data is written to user-space with put_user.
 * Returns -1 if I²C-device didn't send acknowledge, 0 otherwise
 */

static int i2c_getdata(struct saa5249_device *t, int count, u8 *buf)
{
	if(i2c_master_recv(t->client, buf, count)!=count)
		return -1;
	return 0;
}


/*
 *	Standard character-device-driver functions
 */

static int do_saa5249_ioctl(struct file *file, unsigned int cmd, void *arg)
{
	static int virtual_mode = false;
	struct saa5249_device *t = video_drvdata(file);

	switch (cmd) {
	case VTXIOCGETINFO:
	{
		vtx_info_t *info = arg;
		info->version_major = VTX_VER_MAJ;
		info->version_minor = VTX_VER_MIN;
		info->numpages = NUM_DAUS;
		/*info->cct_type = CCT_TYPE;*/
		return 0;
	}

	case VTXIOCCLRPAGE:
	{
		vtx_pagereq_t *req = arg;

		if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
			return -EINVAL;
		memset(t->vdau[req->pgbuf].pgbuf, ' ', sizeof(t->vdau[0].pgbuf));
		t->vdau[req->pgbuf].clrfound = true;
		return 0;
	}

	case VTXIOCCLRFOUND:
	{
		vtx_pagereq_t *req = arg;

		if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
			return -EINVAL;
		t->vdau[req->pgbuf].clrfound = true;
		return 0;
	}

	case VTXIOCPAGEREQ:
	{
		vtx_pagereq_t *req = arg;
		if (!(req->pagemask & PGMASK_PAGE))
			req->page = 0;
		if (!(req->pagemask & PGMASK_HOUR))
			req->hour = 0;
		if (!(req->pagemask & PGMASK_MINUTE))
			req->minute = 0;
		if (req->page < 0 || req->page > 0x8ff) /* 7FF ?? */
			return -EINVAL;
		req->page &= 0x7ff;
		if (req->hour < 0 || req->hour > 0x3f || req->minute < 0 || req->minute > 0x7f ||
			req->pagemask < 0 || req->pagemask >= PGMASK_MAX || req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
			return -EINVAL;
		t->vdau[req->pgbuf].sregs[0] = (req->pagemask & PG_HUND ? 0x10 : 0) | (req->page / 0x100);
		t->vdau[req->pgbuf].sregs[1] = (req->pagemask & PG_TEN ? 0x10 : 0) | ((req->page / 0x10) & 0xf);
		t->vdau[req->pgbuf].sregs[2] = (req->pagemask & PG_UNIT ? 0x10 : 0) | (req->page & 0xf);
		t->vdau[req->pgbuf].sregs[3] = (req->pagemask & HR_TEN ? 0x10 : 0) | (req->hour / 0x10);
		t->vdau[req->pgbuf].sregs[4] = (req->pagemask & HR_UNIT ? 0x10 : 0) | (req->hour & 0xf);
		t->vdau[req->pgbuf].sregs[5] = (req->pagemask & MIN_TEN ? 0x10 : 0) | (req->minute / 0x10);
		t->vdau[req->pgbuf].sregs[6] = (req->pagemask & MIN_UNIT ? 0x10 : 0) | (req->minute & 0xf);
		t->vdau[req->pgbuf].stopped = false;
		t->vdau[req->pgbuf].clrfound = true;
		t->is_searching[req->pgbuf] = true;
		return 0;
	}

	case VTXIOCGETSTAT:
	{
		vtx_pagereq_t *req = arg;
		u8 infobits[10];
		vtx_pageinfo_t info;
		int a;

		if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
			return -EINVAL;
		if (!t->vdau[req->pgbuf].stopped) {
			if (i2c_senddata(t, 2, 0, -1) ||
				i2c_sendbuf(t, 3, sizeof(t->vdau[0].sregs), t->vdau[req->pgbuf].sregs) ||
				i2c_senddata(t, 8, 0, 25, 0, ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ', -1) ||
				i2c_senddata(t, 2, 0, t->vdau[req->pgbuf].sregs[0] | 8, -1) ||
				i2c_senddata(t, 8, 0, 25, 0, -1))
				return -EIO;
			jdelay(PAGE_WAIT);
			if (i2c_getdata(t, 10, infobits))
				return -EIO;

			if (!(infobits[8] & 0x10) && !(infobits[7] & 0xf0) &&	/* check FOUND-bit */
				(memcmp(infobits, t->vdau[req->pgbuf].laststat, sizeof(infobits)) ||
				time_after_eq(jiffies, t->vdau[req->pgbuf].expire)))
			{		/* check if new page arrived */
				if (i2c_senddata(t, 8, 0, 0, 0, -1) ||
					i2c_getdata(t, VTX_PAGESIZE, t->vdau[req->pgbuf].pgbuf))
					return -EIO;
				t->vdau[req->pgbuf].expire = jiffies + PGBUF_EXPIRE;
				memset(t->vdau[req->pgbuf].pgbuf + VTX_PAGESIZE, ' ', VTX_VIRTUALSIZE - VTX_PAGESIZE);
				if (t->virtual_mode) {
					/* Packet X/24 */
					if (i2c_senddata(t, 8, 0, 0x20, 0, -1) ||
						i2c_getdata(t, 40, t->vdau[req->pgbuf].pgbuf + VTX_PAGESIZE + 20 * 40))
						return -EIO;
					/* Packet X/27/0 */
					if (i2c_senddata(t, 8, 0, 0x21, 0, -1) ||
						i2c_getdata(t, 40, t->vdau[req->pgbuf].pgbuf + VTX_PAGESIZE + 16 * 40))
						return -EIO;
					/* Packet 8/30/0...8/30/15
					 * FIXME: AFAIK, the 5249 does hamming-decoding for some bytes in packet 8/30,
					 *        so we should undo this here.
					 */
					if (i2c_senddata(t, 8, 0, 0x22, 0, -1) ||
						i2c_getdata(t, 40, t->vdau[req->pgbuf].pgbuf + VTX_PAGESIZE + 23 * 40))
						return -EIO;
				}
				t->vdau[req->pgbuf].clrfound = false;
				memcpy(t->vdau[req->pgbuf].laststat, infobits, sizeof(infobits));
			} else {
				memcpy(infobits, t->vdau[req->pgbuf].laststat, sizeof(infobits));
			}
		} else {
			memcpy(infobits, t->vdau[req->pgbuf].laststat, sizeof(infobits));
		}

		info.pagenum = ((infobits[8] << 8) & 0x700) | ((infobits[1] << 4) & 0xf0) | (infobits[0] & 0x0f);
		if (info.pagenum < 0x100)
			info.pagenum += 0x800;
		info.hour = ((infobits[5] << 4) & 0x30) | (infobits[4] & 0x0f);
		info.minute = ((infobits[3] << 4) & 0x70) | (infobits[2] & 0x0f);
		info.charset = ((infobits[7] >> 1) & 7);
		info.delete = !!(infobits[3] & 8);
		info.headline = !!(infobits[5] & 4);
		info.subtitle = !!(infobits[5] & 8);
		info.supp_header = !!(infobits[6] & 1);
		info.update = !!(infobits[6] & 2);
		info.inter_seq = !!(infobits[6] & 4);
		info.dis_disp = !!(infobits[6] & 8);
		info.serial = !!(infobits[7] & 1);
		info.notfound = !!(infobits[8] & 0x10);
		info.pblf = !!(infobits[9] & 0x20);
		info.hamming = 0;
		for (a = 0; a <= 7; a++) {
			if (infobits[a] & 0xf0) {
				info.hamming = 1;
				break;
			}
		}
		if (t->vdau[req->pgbuf].clrfound)
			info.notfound = 1;
		if (copy_to_user(req->buffer, &info, sizeof(vtx_pageinfo_t)))
			return -EFAULT;
		if (!info.hamming && !info.notfound)
			t->is_searching[req->pgbuf] = false;
		return 0;
	}

	case VTXIOCGETPAGE:
	{
		vtx_pagereq_t *req = arg;
		int start, end;

		if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS || req->start < 0 ||
			req->start > req->end || req->end >= (virtual_mode ? VTX_VIRTUALSIZE : VTX_PAGESIZE))
			return -EINVAL;
		if (copy_to_user(req->buffer, &t->vdau[req->pgbuf].pgbuf[req->start], req->end - req->start + 1))
			return -EFAULT;

		 /*
		  *	Always read the time directly from SAA5249
		  */

		if (req->start <= 39 && req->end >= 32) {
			int len;
			char buf[16];
			start = max(req->start, 32);
			end = min(req->end, 39);
			len = end - start + 1;
			if (i2c_senddata(t, 8, 0, 0, start, -1) ||
				i2c_getdata(t, len, buf))
				return -EIO;
			if (copy_to_user(req->buffer + start - req->start, buf, len))
				return -EFAULT;
		}
		/* Insert the current header if DAU is still searching for a page */
		if (req->start <= 31 && req->end >= 7 && t->is_searching[req->pgbuf]) {
			char buf[32];
			int len;

			start = max(req->start, 7);
			end = min(req->end, 31);
			len = end - start + 1;
			if (i2c_senddata(t, 8, 0, 0, start, -1) ||
				i2c_getdata(t, len, buf))
				return -EIO;
			if (copy_to_user(req->buffer + start - req->start, buf, len))
				return -EFAULT;
		}
		return 0;
	}

	case VTXIOCSTOPDAU:
	{
		vtx_pagereq_t *req = arg;

		if (req->pgbuf < 0 || req->pgbuf >= NUM_DAUS)
			return -EINVAL;
		t->vdau[req->pgbuf].stopped = true;
		t->is_searching[req->pgbuf] = false;
		return 0;
	}

	case VTXIOCPUTPAGE:
	case VTXIOCSETDISP:
	case VTXIOCPUTSTAT:
		return 0;

	case VTXIOCCLRCACHE:
	{
		if (i2c_senddata(t, 0, NUM_DAUS, 0, 8, -1) || i2c_senddata(t, 11,
			' ', ' ', ' ', ' ', ' ', ' ',
			' ', ' ', ' ', ' ', ' ', ' ',
			' ', ' ', ' ', ' ', ' ', ' ',
			' ', ' ', ' ', ' ', ' ', ' ',
			-1))
			return -EIO;
		if (i2c_senddata(t, 3, 0x20, -1))
			return -EIO;
		jdelay(10 * CLEAR_DELAY);			/* I have no idea how long we have to wait here */
		return 0;
	}

	case VTXIOCSETVIRT:
	{
		/* The SAA5249 has virtual-row reception turned on always */
		t->virtual_mode = (int)(long)arg;
		return 0;
	}
	}
	return -EINVAL;
}

/*
 * Translates old vtx IOCTLs to new ones
 *
 * This keeps new kernel versions compatible with old userspace programs.
 */
static inline unsigned int vtx_fix_command(unsigned int cmd)
{
	switch (cmd) {
	case VTXIOCGETINFO_OLD:
		cmd = VTXIOCGETINFO;
		break;
	case VTXIOCCLRPAGE_OLD:
		cmd = VTXIOCCLRPAGE;
		break;
	case VTXIOCCLRFOUND_OLD:
		cmd = VTXIOCCLRFOUND;
		break;
	case VTXIOCPAGEREQ_OLD:
		cmd = VTXIOCPAGEREQ;
		break;
	case VTXIOCGETSTAT_OLD:
		cmd = VTXIOCGETSTAT;
		break;
	case VTXIOCGETPAGE_OLD:
		cmd = VTXIOCGETPAGE;
		break;
	case VTXIOCSTOPDAU_OLD:
		cmd = VTXIOCSTOPDAU;
		break;
	case VTXIOCPUTPAGE_OLD:
		cmd = VTXIOCPUTPAGE;
		break;
	case VTXIOCSETDISP_OLD:
		cmd = VTXIOCSETDISP;
		break;
	case VTXIOCPUTSTAT_OLD:
		cmd = VTXIOCPUTSTAT;
		break;
	case VTXIOCCLRCACHE_OLD:
		cmd = VTXIOCCLRCACHE;
		break;
	case VTXIOCSETVIRT_OLD:
		cmd = VTXIOCSETVIRT;
		break;
	}
	return cmd;
}

/*
 *	Handle the locking
 */

static int saa5249_ioctl(struct inode *inode, struct file *file,
			 unsigned int cmd, unsigned long arg)
{
	struct saa5249_device *t = video_drvdata(file);
	int err;

	cmd = vtx_fix_command(cmd);
	mutex_lock(&t->lock);
	err = video_usercopy(file, cmd, arg, do_saa5249_ioctl);
	mutex_unlock(&t->lock);
	return err;
}

static int saa5249_open(struct inode *inode, struct file *file)
{
	struct saa5249_device *t = video_drvdata(file);
	int pgbuf;

	if (t->client == NULL)
		return -ENODEV;

	if (test_and_set_bit(0, &t->in_use))
		return -EBUSY;

	if (i2c_senddata(t, 0, 0, -1) || /* Select R11 */
		/* Turn off parity checks (we do this ourselves) */
		i2c_senddata(t, 1, disp_modes[t->disp_mode][0], 0, -1) ||
		/* Display TV-picture, no virtual rows */
		i2c_senddata(t, 4, NUM_DAUS, disp_modes[t->disp_mode][1], disp_modes[t->disp_mode][2], 7, -1))
		/* Set display to page 4 */
	{
		clear_bit(0, &t->in_use);
		return -EIO;
	}

	for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++) {
		memset(t->vdau[pgbuf].pgbuf, ' ', sizeof(t->vdau[0].pgbuf));
		memset(t->vdau[pgbuf].sregs, 0, sizeof(t->vdau[0].sregs));
		memset(t->vdau[pgbuf].laststat, 0, sizeof(t->vdau[0].laststat));
		t->vdau[pgbuf].expire = 0;
		t->vdau[pgbuf].clrfound = true;
		t->vdau[pgbuf].stopped = true;
		t->is_searching[pgbuf] = false;
	}
	t->virtual_mode = false;
	return 0;
}



static int saa5249_release(struct inode *inode, struct file *file)
{
	struct saa5249_device *t = video_drvdata(file);

	i2c_senddata(t, 1, 0x20, -1);		/* Turn off CCT */
	i2c_senddata(t, 5, 3, 3, -1);		/* Turn off TV-display */
	clear_bit(0, &t->in_use);
	return 0;
}

static const struct file_operations saa_fops = {
	.owner		= THIS_MODULE,
	.open		= saa5249_open,
	.release       	= saa5249_release,
	.ioctl          = saa5249_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= v4l_compat_ioctl32,
#endif
	.llseek         = no_llseek,
};

static struct video_device saa_template =
{
	.name		= "saa5249",
	.fops           = &saa_fops,
	.release 	= video_device_release,
};

/* Addresses to scan */
static unsigned short normal_i2c[] = { 0x22 >> 1, I2C_CLIENT_END };

I2C_CLIENT_INSMOD;

static int saa5249_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int pgbuf;
	int err;
	struct video_device *vd;
	struct saa5249_device *t;

	v4l_info(client, "chip found @ 0x%x (%s)\n",
			client->addr << 1, client->adapter->name);
	v4l_info(client, "VideoText version %d.%d\n",
			VTX_VER_MAJ, VTX_VER_MIN);
	t = kzalloc(sizeof(*t), GFP_KERNEL);
	if (t == NULL)
		return -ENOMEM;
	mutex_init(&t->lock);

	/* Now create a video4linux device */
	vd = kmalloc(sizeof(struct video_device), GFP_KERNEL);
	if (vd == NULL) {
		kfree(client);
		return -ENOMEM;
	}
	i2c_set_clientdata(client, vd);
	memcpy(vd, &saa_template, sizeof(*vd));

	for (pgbuf = 0; pgbuf < NUM_DAUS; pgbuf++) {
		memset(t->vdau[pgbuf].pgbuf, ' ', sizeof(t->vdau[0].pgbuf));
		memset(t->vdau[pgbuf].sregs, 0, sizeof(t->vdau[0].sregs));
		memset(t->vdau[pgbuf].laststat, 0, sizeof(t->vdau[0].laststat));
		t->vdau[pgbuf].expire = 0;
		t->vdau[pgbuf].clrfound = true;
		t->vdau[pgbuf].stopped = true;
		t->is_searching[pgbuf] = false;
	}
	video_set_drvdata(vd, t);

	/* Register it */
	err = video_register_device(vd, VFL_TYPE_VTX, -1);
	if (err < 0) {
		kfree(t);
		kfree(vd);
		return err;
	}
	t->client = client;
	return 0;
}

static int saa5249_remove(struct i2c_client *client)
{
	struct video_device *vd = i2c_get_clientdata(client);

	video_unregister_device(vd);
	kfree(video_get_drvdata(vd));
	kfree(vd);
	return 0;
}

static const struct i2c_device_id saa5249_id[] = {
	{ "saa5249", 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, saa5249_id);

static struct v4l2_i2c_driver_data v4l2_i2c_data = {
	.name = "saa5249",
	.driverid = I2C_DRIVERID_SAA5249,
	.probe = saa5249_probe,
	.remove = saa5249_remove,
	.id_table = saa5249_id,
};