aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/usb/gspca/stk1135.c
blob: 48234c9a8b6c3e4b4b927eb654ddb0009aa3d8ba (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
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
/*
 * Syntek STK1135 subdriver
 *
 * Copyright (c) 2013 Ondrej Zary
 *
 * Based on Syntekdriver (stk11xx) by Nicolas VIVIEN:
 *   http://syntekdriver.sourceforge.net
 *
 * 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
 * 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
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#define MODULE_NAME "stk1135"

#include "gspca.h"
#include "stk1135.h"

MODULE_AUTHOR("Ondrej Zary");
MODULE_DESCRIPTION("Syntek STK1135 USB Camera Driver");
MODULE_LICENSE("GPL");


/* specific webcam descriptor */
struct sd {
	struct gspca_dev gspca_dev;	/* !! must be the first item */

	u8 pkt_seq;
	u8 sensor_page;

	bool flip_status;
	u8 flip_debounce;

	struct v4l2_ctrl *hflip;
	struct v4l2_ctrl *vflip;
};

static const struct v4l2_pix_format stk1135_modes[] = {
	/* default mode (this driver supports variable resolution) */
	{640, 480, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
		.bytesperline = 640,
		.sizeimage = 640 * 480,
		.colorspace = V4L2_COLORSPACE_SRGB},
};

/* -- read a register -- */
static u8 reg_r(struct gspca_dev *gspca_dev, u16 index)
{
	struct usb_device *dev = gspca_dev->dev;
	int ret;

	if (gspca_dev->usb_err < 0)
		return 0;
	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
			0x00,
			USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			0x00,
			index,
			gspca_dev->usb_buf, 1,
			500);

	PDEBUG(D_USBI, "reg_r 0x%x=0x%02x", index, gspca_dev->usb_buf[0]);
	if (ret < 0) {
		pr_err("reg_r 0x%x err %d\n", index, ret);
		gspca_dev->usb_err = ret;
		return 0;
	}

	return gspca_dev->usb_buf[0];
}

/* -- write a register -- */
static void reg_w(struct gspca_dev *gspca_dev, u16 index, u8 val)
{
	int ret;
	struct usb_device *dev = gspca_dev->dev;

	if (gspca_dev->usb_err < 0)
		return;
	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			0x01,
			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			val,
			index,
			NULL,
			0,
			500);
	PDEBUG(D_USBO, "reg_w 0x%x:=0x%02x", index, val);
	if (ret < 0) {
		pr_err("reg_w 0x%x err %d\n", index, ret);
		gspca_dev->usb_err = ret;
	}
}

static void reg_w_mask(struct gspca_dev *gspca_dev, u16 index, u8 val, u8 mask)
{
	val = (reg_r(gspca_dev, index) & ~mask) | (val & mask);
	reg_w(gspca_dev, index, val);
}

/* this function is called at probe time */
static int sd_config(struct gspca_dev *gspca_dev,
			const struct usb_device_id *id)
{
	gspca_dev->cam.cam_mode = stk1135_modes;
	gspca_dev->cam.nmodes = ARRAY_SIZE(stk1135_modes);
	return 0;
}

static int stk1135_serial_wait_ready(struct gspca_dev *gspca_dev)
{
	int i = 0;
	u8 val;

	do {
		val = reg_r(gspca_dev, STK1135_REG_SICTL + 1);
		if (i++ > 500) { /* maximum retry count */
			pr_err("serial bus timeout: status=0x%02x\n", val);
			return -1;
		}
	/* repeat if BUSY or WRITE/READ not finished */
	} while ((val & 0x10) || !(val & 0x05));

	return 0;
}

static u8 sensor_read_8(struct gspca_dev *gspca_dev, u8 addr)
{
	reg_w(gspca_dev, STK1135_REG_SBUSR, addr);
	/* begin read */
	reg_w(gspca_dev, STK1135_REG_SICTL, 0x20);
	/* wait until finished */
	if (stk1135_serial_wait_ready(gspca_dev)) {
		pr_err("Sensor read failed\n");
		return 0;
	}

	return reg_r(gspca_dev, STK1135_REG_SBUSR + 1);
}

static u16 sensor_read_16(struct gspca_dev *gspca_dev, u8 addr)
{
	return (sensor_read_8(gspca_dev, addr) << 8) |
		sensor_read_8(gspca_dev, 0xf1);
}

static void sensor_write_8(struct gspca_dev *gspca_dev, u8 addr, u8 data)
{
	/* load address and data registers */
	reg_w(gspca_dev, STK1135_REG_SBUSW, addr);
	reg_w(gspca_dev, STK1135_REG_SBUSW + 1, data);
	/* begin write */
	reg_w(gspca_dev, STK1135_REG_SICTL, 0x01);
	/* wait until finished */
	if (stk1135_serial_wait_ready(gspca_dev)) {
		pr_err("Sensor write failed\n");
		return;
	}
}

static void sensor_write_16(struct gspca_dev *gspca_dev, u8 addr, u16 data)
{
	sensor_write_8(gspca_dev, addr, data >> 8);
	sensor_write_8(gspca_dev, 0xf1, data & 0xff);
}

static void sensor_set_page(struct gspca_dev *gspca_dev, u8 page)
{
	struct sd *sd = (struct sd *) gspca_dev;

	if (page != sd->sensor_page) {
		sensor_write_16(gspca_dev, 0xf0, page);
		sd->sensor_page = page;
	}
}

static u16 sensor_read(struct gspca_dev *gspca_dev, u16 reg)
{
	sensor_set_page(gspca_dev, reg >> 8);
	return sensor_read_16(gspca_dev, reg & 0xff);
}

static void sensor_write(struct gspca_dev *gspca_dev, u16 reg, u16 val)
{
	sensor_set_page(gspca_dev, reg >> 8);
	sensor_write_16(gspca_dev, reg & 0xff, val);
}

static void sensor_write_mask(struct gspca_dev *gspca_dev,
			u16 reg, u16 val, u16 mask)
{
	val = (sensor_read(gspca_dev, reg) & ~mask) | (val & mask);
	sensor_write(gspca_dev, reg, val);
}

struct sensor_val {
	u16 reg;
	u16 val;
};

/* configure MT9M112 sensor */
static void stk1135_configure_mt9m112(struct gspca_dev *gspca_dev)
{
	static const struct sensor_val cfg[] = {
		/* restart&reset, chip enable, reserved */
		{ 0x00d, 0x000b }, { 0x00d, 0x0008 }, { 0x035, 0x0022 },
		/* mode ctl: AWB on, AE both, clip aper corr, defect corr, AE */
		{ 0x106, 0x700e },

		{ 0x2dd, 0x18e0 }, /* B-R thresholds, */

		/* AWB */
		{ 0x21f, 0x0180 }, /* Cb and Cr limits */
		{ 0x220, 0xc814 }, { 0x221, 0x8080 }, /* lum limits, RGB gain */
		{ 0x222, 0xa078 }, { 0x223, 0xa078 }, /* R, B limit */
		{ 0x224, 0x5f20 }, { 0x228, 0xea02 }, /* mtx adj lim, adv ctl */
		{ 0x229, 0x867a }, /* wide gates */

		/* Color correction */
		/* imager gains base, delta, delta signs */
		{ 0x25e, 0x594c }, { 0x25f, 0x4d51 }, { 0x260, 0x0002 },
		/* AWB adv ctl 2, gain offs */
		{ 0x2ef, 0x0008 }, { 0x2f2, 0x0000 },
		/* base matrix signs, scale K1-5, K6-9 */
		{ 0x202, 0x00ee }, { 0x203, 0x3923 }, { 0x204, 0x0724 },
		/* base matrix coef */
		{ 0x209, 0x00cd }, { 0x20a, 0x0093 }, { 0x20b, 0x0004 },/*K1-3*/
		{ 0x20c, 0x005c }, { 0x20d, 0x00d9 }, { 0x20e, 0x0053 },/*K4-6*/
		{ 0x20f, 0x0008 }, { 0x210, 0x0091 }, { 0x211, 0x00cf },/*K7-9*/
		{ 0x215, 0x0000 }, /* delta mtx signs */
		/* delta matrix coef */
		{ 0x216, 0x0000 }, { 0x217, 0x0000 }, { 0x218, 0x0000 },/*D1-3*/
		{ 0x219, 0x0000 }, { 0x21a, 0x0000 }, { 0x21b, 0x0000 },/*D4-6*/
		{ 0x21c, 0x0000 }, { 0x21d, 0x0000 }, { 0x21e, 0x0000 },/*D7-9*/
		/* enable & disable manual WB to apply color corr. settings */
		{ 0x106, 0xf00e }, { 0x106, 0x700e },

		/* Lens shading correction */
		{ 0x180, 0x0007 }, /* control */
		/* vertical knee 0, 2+1, 4+3 */
		{ 0x181, 0xde13 }, { 0x182, 0xebe2 }, { 0x183, 0x00f6 }, /* R */
		{ 0x184, 0xe114 }, { 0x185, 0xeadd }, { 0x186, 0xfdf6 }, /* G */
		{ 0x187, 0xe511 }, { 0x188, 0xede6 }, { 0x189, 0xfbf7 }, /* B */
		/* horizontal knee 0, 2+1, 4+3, 5 */
		{ 0x18a, 0xd613 }, { 0x18b, 0xedec }, /* R .. */
		{ 0x18c, 0xf9f2 }, { 0x18d, 0x0000 }, /* .. R */
		{ 0x18e, 0xd815 }, { 0x18f, 0xe9ea }, /* G .. */
		{ 0x190, 0xf9f1 }, { 0x191, 0x0002 }, /* .. G */
		{ 0x192, 0xde10 }, { 0x193, 0xefef }, /* B .. */
		{ 0x194, 0xfbf4 }, { 0x195, 0x0002 }, /* .. B */
		/* vertical knee 6+5, 8+7 */
		{ 0x1b6, 0x0e06 }, { 0x1b7, 0x2713 }, /* R */
		{ 0x1b8, 0x1106 }, { 0x1b9, 0x2713 }, /* G */
		{ 0x1ba, 0x0c03 }, { 0x1bb, 0x2a0f }, /* B */
		/* horizontal knee 7+6, 9+8, 10 */
		{ 0x1bc, 0x1208 }, { 0x1bd, 0x1a16 }, { 0x1be, 0x0022 }, /* R */
		{ 0x1bf, 0x150a }, { 0x1c0, 0x1c1a }, { 0x1c1, 0x002d }, /* G */
		{ 0x1c2, 0x1109 }, { 0x1c3, 0x1414 }, { 0x1c4, 0x002a }, /* B */
		{ 0x106, 0x740e }, /* enable lens shading correction */

		/* Gamma correction - context A */
		{ 0x153, 0x0b03 }, { 0x154, 0x4722 }, { 0x155, 0xac82 },
		{ 0x156, 0xdac7 }, { 0x157, 0xf5e9 }, { 0x158, 0xff00 },
		/* Gamma correction - context B */
		{ 0x1dc, 0x0b03 }, { 0x1dd, 0x4722 }, { 0x1de, 0xac82 },
		{ 0x1df, 0xdac7 }, { 0x1e0, 0xf5e9 }, { 0x1e1, 0xff00 },

		/* output format: RGB, invert output pixclock, output bayer */
		{ 0x13a, 0x4300 }, { 0x19b, 0x4300 }, /* for context A, B */
		{ 0x108, 0x0180 }, /* format control - enable bayer row flip */

		{ 0x22f, 0xd100 }, { 0x29c, 0xd100 }, /* AE A, B */

		/* default prg conf, prg ctl - by 0x2d2, prg advance - PA1 */
		{ 0x2d2, 0x0000 }, { 0x2cc, 0x0004 }, { 0x2cb, 0x0001 },

		{ 0x22e, 0x0c3c }, { 0x267, 0x1010 }, /* AE tgt ctl, gain lim */

		/* PLL */
		{ 0x065, 0xa000 }, /* clk ctl - enable PLL (clear bit 14) */
		{ 0x066, 0x2003 }, { 0x067, 0x0501 }, /* PLL M=128, N=3, P=1 */
		{ 0x065, 0x2000 }, /* disable PLL bypass (clear bit 15) */

		{ 0x005, 0x01b8 }, { 0x007, 0x00d8 }, /* horiz blanking B, A */

		/* AE line size, shutter delay limit */
		{ 0x239, 0x06c0 }, { 0x23b, 0x040e }, /* for context A */
		{ 0x23a, 0x06c0 }, { 0x23c, 0x0564 }, /* for context B */
		/* shutter width basis 60Hz, 50Hz */
		{ 0x257, 0x0208 }, { 0x258, 0x0271 }, /* for context A */
		{ 0x259, 0x0209 }, { 0x25a, 0x0271 }, /* for context B */

		{ 0x25c, 0x120d }, { 0x25d, 0x1712 }, /* flicker 60Hz, 50Hz */
		{ 0x264, 0x5e1c }, /* reserved */
		/* flicker, AE gain limits, gain zone limits */
		{ 0x25b, 0x0003 }, { 0x236, 0x7810 }, { 0x237, 0x8304 },

		{ 0x008, 0x0021 }, /* vert blanking A */
	};
	int i;
	u16 width, height;

	for (i = 0; i < ARRAY_SIZE(cfg); i++)
		sensor_write(gspca_dev, cfg[i].reg, cfg[i].val);

	/* set output size */
	width = gspca_dev->pixfmt.width;
	height = gspca_dev->pixfmt.height;
	if (width <= 640 && height <= 512) { /* context A (half readout speed)*/
		sensor_write(gspca_dev, 0x1a7, width);
		sensor_write(gspca_dev, 0x1aa, height);
		/* set read mode context A */
		sensor_write(gspca_dev, 0x0c8, 0x0000);
		/* set resize, read mode, vblank, hblank context A */
		sensor_write(gspca_dev, 0x2c8, 0x0000);
	} else { /* context B (full readout speed) */
		sensor_write(gspca_dev, 0x1a1, width);
		sensor_write(gspca_dev, 0x1a4, height);
		/* set read mode context B */
		sensor_write(gspca_dev, 0x0c8, 0x0008);
		/* set resize, read mode, vblank, hblank context B */
		sensor_write(gspca_dev, 0x2c8, 0x040b);
	}
}

static void stk1135_configure_clock(struct gspca_dev *gspca_dev)
{
	/* configure SCLKOUT */
	reg_w(gspca_dev, STK1135_REG_TMGEN, 0x12);
	/* set 1 clock per pixel */
	/* and positive edge clocked pulse high when pixel counter = 0 */
	reg_w(gspca_dev, STK1135_REG_TCP1 + 0, 0x41);
	reg_w(gspca_dev, STK1135_REG_TCP1 + 1, 0x00);
	reg_w(gspca_dev, STK1135_REG_TCP1 + 2, 0x00);
	reg_w(gspca_dev, STK1135_REG_TCP1 + 3, 0x00);

	/* enable CLKOUT for sensor */
	reg_w(gspca_dev, STK1135_REG_SENSO + 0, 0x10);
	/* disable STOP clock */
	reg_w(gspca_dev, STK1135_REG_SENSO + 1, 0x00);
	/* set lower 8 bits of PLL feedback divider */
	reg_w(gspca_dev, STK1135_REG_SENSO + 3, 0x07);
	/* set other PLL parameters */
	reg_w(gspca_dev, STK1135_REG_PLLFD, 0x06);
	/* enable timing generator */
	reg_w(gspca_dev, STK1135_REG_TMGEN, 0x80);
	/* enable PLL */
	reg_w(gspca_dev, STK1135_REG_SENSO + 2, 0x04);

	/* set serial interface clock divider (30MHz/0x1f*16+2) = 60240 kHz) */
	reg_w(gspca_dev, STK1135_REG_SICTL + 2, 0x1f);

	/* wait a while for sensor to catch up */
	udelay(1000);
}

static void stk1135_camera_disable(struct gspca_dev *gspca_dev)
{
	/* set capture end Y position to 0 */
	reg_w(gspca_dev, STK1135_REG_CIEPO + 2, 0x00);
	reg_w(gspca_dev, STK1135_REG_CIEPO + 3, 0x00);
	/* disable capture */
	reg_w_mask(gspca_dev, STK1135_REG_SCTRL, 0x00, 0x80);

	/* enable sensor standby and diasble chip enable */
	sensor_write_mask(gspca_dev, 0x00d, 0x0004, 0x000c);

	/* disable PLL */
	reg_w_mask(gspca_dev, STK1135_REG_SENSO + 2, 0x00, 0x01);
	/* disable timing generator */
	reg_w(gspca_dev, STK1135_REG_TMGEN, 0x00);
	/* enable STOP clock */
	reg_w(gspca_dev, STK1135_REG_SENSO + 1, 0x20);
	/* disable CLKOUT for sensor */
	reg_w(gspca_dev, STK1135_REG_SENSO, 0x00);

	/* disable sensor (GPIO5) and enable GPIO0,3,6 (?) - sensor standby? */
	reg_w(gspca_dev, STK1135_REG_GCTRL, 0x49);
}

/* this function is called at probe and resume time */
static int sd_init(struct gspca_dev *gspca_dev)
{
	u16 sensor_id;
	char *sensor_name;
	struct sd *sd = (struct sd *) gspca_dev;

	/* set GPIO3,4,5,6 direction to output */
	reg_w(gspca_dev, STK1135_REG_GCTRL + 2, 0x78);
	/* enable sensor (GPIO5) */
	reg_w(gspca_dev, STK1135_REG_GCTRL, (1 << 5));
	/* disable ROM interface */
	reg_w(gspca_dev, STK1135_REG_GCTRL + 3, 0x80);
	/* enable interrupts from GPIO8 (flip sensor) and GPIO9 (???) */
	reg_w(gspca_dev, STK1135_REG_ICTRL + 1, 0x00);
	reg_w(gspca_dev, STK1135_REG_ICTRL + 3, 0x03);
	/* enable remote wakeup from GPIO9 (???) */
	reg_w(gspca_dev, STK1135_REG_RMCTL + 1, 0x00);
	reg_w(gspca_dev, STK1135_REG_RMCTL + 3, 0x02);

	/* reset serial interface */
	reg_w(gspca_dev, STK1135_REG_SICTL, 0x80);
	reg_w(gspca_dev, STK1135_REG_SICTL, 0x00);
	/* set sensor address */
	reg_w(gspca_dev, STK1135_REG_SICTL + 3, 0xba);
	/* disable alt 2-wire serial interface */
	reg_w(gspca_dev, STK1135_REG_ASIC + 3, 0x00);

	stk1135_configure_clock(gspca_dev);

	/* read sensor ID */
	sd->sensor_page = 0xff;
	sensor_id = sensor_read(gspca_dev, 0x000);

	switch (sensor_id) {
	case 0x148c:
		sensor_name = "MT9M112";
		break;
	default:
		sensor_name = "unknown";
	}
	pr_info("Detected sensor type %s (0x%x)\n", sensor_name, sensor_id);

	stk1135_camera_disable(gspca_dev);

	return gspca_dev->usb_err;
}

/* -- start the camera -- */
static int sd_start(struct gspca_dev *gspca_dev)
{
	struct sd *sd = (struct sd *) gspca_dev;
	u16 width, height;

	/* enable sensor (GPIO5) */
	reg_w(gspca_dev, STK1135_REG_GCTRL, (1 << 5));

	stk1135_configure_clock(gspca_dev);

	/* set capture start position X = 0, Y = 0 */
	reg_w(gspca_dev, STK1135_REG_CISPO + 0, 0x00);
	reg_w(gspca_dev, STK1135_REG_CISPO + 1, 0x00);
	reg_w(gspca_dev, STK1135_REG_CISPO + 2, 0x00);
	reg_w(gspca_dev, STK1135_REG_CISPO + 3, 0x00);

	/* set capture end position */
	width = gspca_dev->pixfmt.width;
	height = gspca_dev->pixfmt.height;
	reg_w(gspca_dev, STK1135_REG_CIEPO + 0, width & 0xff);
	reg_w(gspca_dev, STK1135_REG_CIEPO + 1, width >> 8);
	reg_w(gspca_dev, STK1135_REG_CIEPO + 2, height & 0xff);
	reg_w(gspca_dev, STK1135_REG_CIEPO + 3, height >> 8);

	/* set 8-bit mode */
	reg_w(gspca_dev, STK1135_REG_SCTRL, 0x20);

	stk1135_configure_mt9m112(gspca_dev);

	/* enable capture */
	reg_w_mask(gspca_dev, STK1135_REG_SCTRL, 0x80, 0x80);

	if (gspca_dev->usb_err >= 0)
		PDEBUG(D_STREAM, "camera started alt: 0x%02x",
				gspca_dev->alt);

	sd->pkt_seq = 0;

	return gspca_dev->usb_err;
}

static void sd_stopN(struct gspca_dev *gspca_dev)
{
	struct usb_device *dev = gspca_dev->dev;

	usb_set_interface(dev, gspca_dev->iface, 0);

	stk1135_camera_disable(gspca_dev);

	PDEBUG(D_STREAM, "camera stopped");
}

static void sd_pkt_scan(struct gspca_dev *gspca_dev,
			u8 *data,			/* isoc packet */
			int len)			/* iso packet length */
{
	struct sd *sd = (struct sd *) gspca_dev;
	int skip = sizeof(struct stk1135_pkt_header);
	bool flip;
	enum gspca_packet_type pkt_type = INTER_PACKET;
	struct stk1135_pkt_header *hdr = (void *)data;
	u8 seq;

	if (len < 4) {
		PDEBUG(D_PACK, "received short packet (less than 4 bytes)");
		return;
	}

	/* GPIO 8 is flip sensor (1 = normal position, 0 = flipped to back) */
	flip = !(le16_to_cpu(hdr->gpio) & (1 << 8));
	/* it's a switch, needs software debounce */
	if (sd->flip_status != flip)
		sd->flip_debounce++;
	else
		sd->flip_debounce = 0;

	/* check sequence number (not present in new frame packets) */
	if (!(hdr->flags & STK1135_HDR_FRAME_START)) {
		seq = hdr->seq & STK1135_HDR_SEQ_MASK;
		if (seq != sd->pkt_seq) {
			PDEBUG(D_PACK, "received out-of-sequence packet");
			/* resync sequence and discard packet */
			sd->pkt_seq = seq;
			gspca_dev->last_packet_type = DISCARD_PACKET;
			return;
		}
	}
	sd->pkt_seq++;
	if (sd->pkt_seq > STK1135_HDR_SEQ_MASK)
		sd->pkt_seq = 0;

	if (len == sizeof(struct stk1135_pkt_header))
		return;

	if (hdr->flags & STK1135_HDR_FRAME_START) { /* new frame */
		skip = 8;	/* the header is longer */
		gspca_frame_add(gspca_dev, LAST_PACKET, data, 0);
		pkt_type = FIRST_PACKET;
	}
	gspca_frame_add(gspca_dev, pkt_type, data + skip, len - skip);
}

static void sethflip(struct gspca_dev *gspca_dev, s32 val)
{
	struct sd *sd = (struct sd *) gspca_dev;

	if (sd->flip_status)
		val = !val;
	sensor_write_mask(gspca_dev, 0x020, val ? 0x0002 : 0x0000 , 0x0002);
}

static void setvflip(struct gspca_dev *gspca_dev, s32 val)
{
	struct sd *sd = (struct sd *) gspca_dev;

	if (sd->flip_status)
		val = !val;
	sensor_write_mask(gspca_dev, 0x020, val ? 0x0001 : 0x0000 , 0x0001);
}

static void stk1135_dq_callback(struct gspca_dev *gspca_dev)
{
	struct sd *sd = (struct sd *) gspca_dev;

	if (sd->flip_debounce > 100) {
		sd->flip_status = !sd->flip_status;
		sethflip(gspca_dev, v4l2_ctrl_g_ctrl(sd->hflip));
		setvflip(gspca_dev, v4l2_ctrl_g_ctrl(sd->vflip));
	}
}

static int sd_s_ctrl(struct v4l2_ctrl *ctrl)
{
	struct gspca_dev *gspca_dev =
		container_of(ctrl->handler, struct gspca_dev, ctrl_handler);

	gspca_dev->usb_err = 0;

	if (!gspca_dev->streaming)
		return 0;

	switch (ctrl->id) {
	case V4L2_CID_HFLIP:
		sethflip(gspca_dev, ctrl->val);
		break;
	case V4L2_CID_VFLIP:
		setvflip(gspca_dev, ctrl->val);
		break;
	}

	return gspca_dev->usb_err;
}

static const struct v4l2_ctrl_ops sd_ctrl_ops = {
	.s_ctrl = sd_s_ctrl,
};

static int sd_init_controls(struct gspca_dev *gspca_dev)
{
	struct sd *sd = (struct sd *) gspca_dev;
	struct v4l2_ctrl_handler *hdl = &gspca_dev->ctrl_handler;

	gspca_dev->vdev.ctrl_handler = hdl;
	v4l2_ctrl_handler_init(hdl, 2);
	sd->hflip = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
			V4L2_CID_HFLIP, 0, 1, 1, 0);
	sd->vflip = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
			V4L2_CID_VFLIP, 0, 1, 1, 0);

	if (hdl->error) {
		pr_err("Could not initialize controls\n");
		return hdl->error;
	}
	return 0;
}

static void stk1135_try_fmt(struct gspca_dev *gspca_dev, struct v4l2_format *fmt)
{
	fmt->fmt.pix.width = clamp(fmt->fmt.pix.width, 32U, 1280U);
	fmt->fmt.pix.height = clamp(fmt->fmt.pix.height, 32U, 1024U);
	/* round up to even numbers */
	fmt->fmt.pix.width += (fmt->fmt.pix.width & 1);
	fmt->fmt.pix.height += (fmt->fmt.pix.height & 1);

	fmt->fmt.pix.bytesperline = fmt->fmt.pix.width;
	fmt->fmt.pix.sizeimage = fmt->fmt.pix.width * fmt->fmt.pix.height;
}

static int stk1135_enum_framesizes(struct gspca_dev *gspca_dev,
			struct v4l2_frmsizeenum *fsize)
{
	if (fsize->index != 0 || fsize->pixel_format != V4L2_PIX_FMT_SBGGR8)
		return -EINVAL;

	fsize->type = V4L2_FRMSIZE_TYPE_STEPWISE;
	fsize->stepwise.min_width = 32;
	fsize->stepwise.min_height = 32;
	fsize->stepwise.max_width = 1280;
	fsize->stepwise.max_height = 1024;
	fsize->stepwise.step_width = 2;
	fsize->stepwise.step_height = 2;

	return 0;
}

/* sub-driver description */
static const struct sd_desc sd_desc = {
	.name = MODULE_NAME,
	.config = sd_config,
	.init = sd_init,
	.init_controls = sd_init_controls,
	.start = sd_start,
	.stopN = sd_stopN,
	.pkt_scan = sd_pkt_scan,
	.dq_callback = stk1135_dq_callback,
	.try_fmt = stk1135_try_fmt,
	.enum_framesizes = stk1135_enum_framesizes,
};

/* -- module initialisation -- */
static const struct usb_device_id device_table[] = {
	{USB_DEVICE(0x174f, 0x6a31)},	/* ASUS laptop, MT9M112 sensor */
	{}
};
MODULE_DEVICE_TABLE(usb, device_table);

/* -- device connect -- */
static int sd_probe(struct usb_interface *intf,
			const struct usb_device_id *id)
{
	return gspca_dev_probe(intf, id, &sd_desc, sizeof(struct sd),
				THIS_MODULE);
}

static struct usb_driver sd_driver = {
	.name = MODULE_NAME,
	.id_table = device_table,
	.probe = sd_probe,
	.disconnect = gspca_disconnect,
#ifdef CONFIG_PM
	.suspend = gspca_suspend,
	.resume = gspca_resume,
	.reset_resume = gspca_resume,
#endif
};

module_usb_driver(sd_driver);