Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  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
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *		Pixart PAC7311 library
 *		Copyright (C) 2005 Thomas Kaiser thomas@kaiser-linux.li
 *
 * V4L2 by Jean-Francois Moine <http://moinejf.free.fr>
 */

/* Some documentation about various registers as determined by trial and error.
 *
 * Register page 1:
 *
 * Address	Description
 * 0x08		Unknown compressor related, must always be 8 except when not
 *		in 640x480 resolution and page 4 reg 2 <= 3 then set it to 9 !
 * 0x1b		Auto white balance related, bit 0 is AWB enable (inverted)
 *		bits 345 seem to toggle per color gains on/off (inverted)
 * 0x78		Global control, bit 6 controls the LED (inverted)
 * 0x80		Compression balance, interesting settings:
 *		0x01 Use this to allow the camera to switch to higher compr.
 *		     on the fly. Needed to stay within bandwidth @ 640x480@30
 *		0x1c From usb captures under Windows for 640x480
 *		0x2a Values >= this switch the camera to a lower compression,
 *		     using the same table for both luminance and chrominance.
 *		     This gives a sharper picture. Usable only at 640x480@ <
 *		     15 fps or 320x240 / 160x120. Note currently the driver
 *		     does not use this as the quality gain is small and the
 *		     generated JPG-s are only understood by v4l-utils >= 0.8.9
 *		0x3f From usb captures under Windows for 320x240
 *		0x69 From usb captures under Windows for 160x120
 *
 * Register page 4:
 *
 * Address	Description
 * 0x02		Clock divider 2-63, fps =~ 60 / val. Must be a multiple of 3 on
 *		the 7302, so one of 3, 6, 9, ..., except when between 6 and 12?
 * 0x0f		Master gain 1-245, low value = high gain
 * 0x10		Another gain 0-15, limited influence (1-2x gain I guess)
 * 0x21		Bitfield: 0-1 unused, 2-3 vflip/hflip, 4-5 unknown, 6-7 unused
 *		Note setting vflip disabled leads to a much lower image quality,
 *		so we always vflip, and tell userspace to flip it back
 * 0x27		Seems to toggle various gains on / off, Setting bit 7 seems to
 *		completely disable the analog amplification block. Set to 0x68
 *		for max gain, 0x14 for minimal gain.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#define MODULE_NAME "pac7311"

#include <linux/input.h>
#include "gspca.h"
/* Include pac common sof detection functions */
#include "pac_common.h"

#define PAC7311_GAIN_DEFAULT     122
#define PAC7311_EXPOSURE_DEFAULT   3 /* 20 fps, avoid using high compr. */

MODULE_AUTHOR("Thomas Kaiser thomas@kaiser-linux.li");
MODULE_DESCRIPTION("Pixart PAC7311");
MODULE_LICENSE("GPL");

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

	struct v4l2_ctrl *contrast;
	struct v4l2_ctrl *hflip;

	u8 sof_read;
	u8 autogain_ignore_frames;

	atomic_t avg_lum;
};

static const struct v4l2_pix_format vga_mode[] = {
	{160, 120, V4L2_PIX_FMT_PJPG, V4L2_FIELD_NONE,
		.bytesperline = 160,
		.sizeimage = 160 * 120 * 3 / 8 + 590,
		.colorspace = V4L2_COLORSPACE_JPEG,
		.priv = 2},
	{320, 240, V4L2_PIX_FMT_PJPG, V4L2_FIELD_NONE,
		.bytesperline = 320,
		.sizeimage = 320 * 240 * 3 / 8 + 590,
		.colorspace = V4L2_COLORSPACE_JPEG,
		.priv = 1},
	{640, 480, V4L2_PIX_FMT_PJPG, V4L2_FIELD_NONE,
		.bytesperline = 640,
		.sizeimage = 640 * 480 * 3 / 8 + 590,
		.colorspace = V4L2_COLORSPACE_JPEG,
		.priv = 0},
};

#define LOAD_PAGE4		254
#define END_OF_SEQUENCE		0

static const __u8 init_7311[] = {
	0xff, 0x01,
	0x78, 0x40,	/* Bit_0=start stream, Bit_6=LED */
	0x78, 0x40,	/* Bit_0=start stream, Bit_6=LED */
	0x78, 0x44,	/* Bit_0=start stream, Bit_6=LED */
	0xff, 0x04,
	0x27, 0x80,
	0x28, 0xca,
	0x29, 0x53,
	0x2a, 0x0e,
	0xff, 0x01,
	0x3e, 0x20,
};

static const __u8 start_7311[] = {
/*	index, len, [value]* */
	0xff, 1,	0x01,		/* page 1 */
	0x02, 43,	0x48, 0x0a, 0x40, 0x08, 0x00, 0x00, 0x08, 0x00,
			0x06, 0xff, 0x11, 0xff, 0x5a, 0x30, 0x90, 0x4c,
			0x00, 0x07, 0x00, 0x0a, 0x10, 0x00, 0xa0, 0x10,
			0x02, 0x00, 0x00, 0x00, 0x00, 0x0b, 0x01, 0x00,
			0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
			0x00, 0x00, 0x00,
	0x3e, 42,	0x00, 0x00, 0x78, 0x52, 0x4a, 0x52, 0x78, 0x6e,
			0x48, 0x46, 0x48, 0x6e, 0x5f, 0x49, 0x42, 0x49,
			0x5f, 0x5f, 0x49, 0x42, 0x49, 0x5f, 0x6e, 0x48,
			0x46, 0x48, 0x6e, 0x78, 0x52, 0x4a, 0x52, 0x78,
			0x00, 0x00, 0x09, 0x1b, 0x34, 0x49, 0x5c, 0x9b,
			0xd0, 0xff,
	0x78, 6,	0x44, 0x00, 0xf2, 0x01, 0x01, 0x80,
	0x7f, 18,	0x2a, 0x1c, 0x00, 0xc8, 0x02, 0x58, 0x03, 0x84,
			0x12, 0x00, 0x1a, 0x04, 0x08, 0x0c, 0x10, 0x14,
			0x18, 0x20,
	0x96, 3,	0x01, 0x08, 0x04,
	0xa0, 4,	0x44, 0x44, 0x44, 0x04,
	0xf0, 13,	0x01, 0x00, 0x00, 0x00, 0x22, 0x00, 0x20, 0x00,
			0x3f, 0x00, 0x0a, 0x01, 0x00,
	0xff, 1,	0x04,		/* page 4 */
	0, LOAD_PAGE4,			/* load the page 4 */
	0x11, 1,	0x01,
	0, END_OF_SEQUENCE		/* end of sequence */
};

#define SKIP		0xaa
/* page 4 - the value SKIP says skip the index - see reg_w_page() */
static const __u8 page4_7311[] = {
	SKIP, SKIP, 0x04, 0x54, 0x07, 0x2b, 0x09, 0x0f,
	0x09, 0x00, SKIP, SKIP, 0x07, 0x00, 0x00, 0x62,
	0x08, SKIP, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00,
	0x00, 0x00, 0x00, 0x03, 0xa0, 0x01, 0xf4, SKIP,
	SKIP, 0x00, 0x08, SKIP, 0x03, SKIP, 0x00, 0x68,
	0xca, 0x10, 0x06, 0x78, 0x00, 0x00, 0x00, 0x00,
	0x23, 0x28, 0x04, 0x11, 0x00, 0x00
};

static void reg_w_buf(struct gspca_dev *gspca_dev,
		  __u8 index,
		  const u8 *buffer, int len)
{
	int ret;

	if (gspca_dev->usb_err < 0)
		return;
	memcpy(gspca_dev->usb_buf, buffer, len);
	ret = usb_control_msg(gspca_dev->dev,
			usb_sndctrlpipe(gspca_dev->dev, 0),
			0,		/* request */
			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			0,		/* value */
			index, gspca_dev->usb_buf, len,
			500);
	if (ret < 0) {
		pr_err("reg_w_buf() failed index 0x%02x, error %d\n",
		       index, ret);
		gspca_dev->usb_err = ret;
	}
}


static void reg_w(struct gspca_dev *gspca_dev,
		  __u8 index,
		  __u8 value)
{
	int ret;

	if (gspca_dev->usb_err < 0)
		return;
	gspca_dev->usb_buf[0] = value;
	ret = usb_control_msg(gspca_dev->dev,
			usb_sndctrlpipe(gspca_dev->dev, 0),
			0,			/* request */
			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
			0, index, gspca_dev->usb_buf, 1,
			500);
	if (ret < 0) {
		pr_err("reg_w() failed index 0x%02x, value 0x%02x, error %d\n",
		       index, value, ret);
		gspca_dev->usb_err = ret;
	}
}

static void reg_w_seq(struct gspca_dev *gspca_dev,
		const __u8 *seq, int len)
{
	while (--len >= 0) {
		reg_w(gspca_dev, seq[0], seq[1]);
		seq += 2;
	}
}

/* load the beginning of a page */
static void reg_w_page(struct gspca_dev *gspca_dev,
			const __u8 *page, int len)
{
	int index;
	int ret = 0;

	if (gspca_dev->usb_err < 0)
		return;
	for (index = 0; index < len; index++) {
		if (page[index] == SKIP)		/* skip this index */
			continue;
		gspca_dev->usb_buf[0] = page[index];
		ret = usb_control_msg(gspca_dev->dev,
				usb_sndctrlpipe(gspca_dev->dev, 0),
				0,			/* request */
			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
				0, index, gspca_dev->usb_buf, 1,
				500);
		if (ret < 0) {
			pr_err("reg_w_page() failed index 0x%02x, value 0x%02x, error %d\n",
			       index, page[index], ret);
			gspca_dev->usb_err = ret;
			break;
		}
	}
}

/* output a variable sequence */
static void reg_w_var(struct gspca_dev *gspca_dev,
			const __u8 *seq,
			const __u8 *page4, unsigned int page4_len)
{
	int index, len;

	for (;;) {
		index = *seq++;
		len = *seq++;
		switch (len) {
		case END_OF_SEQUENCE:
			return;
		case LOAD_PAGE4:
			reg_w_page(gspca_dev, page4, page4_len);
			break;
		default:
			if (len > USB_BUF_SZ) {
				gspca_err(gspca_dev, "Incorrect variable sequence\n");
				return;
			}
			while (len > 0) {
				if (len < 8) {
					reg_w_buf(gspca_dev,
						index, seq, len);
					seq += len;
					break;
				}
				reg_w_buf(gspca_dev, index, seq, 8);
				seq += 8;
				index += 8;
				len -= 8;
			}
		}
	}
	/* not reached */
}

/* this function is called at probe time for pac7311 */
static int sd_config(struct gspca_dev *gspca_dev,
			const struct usb_device_id *id)
{
	struct cam *cam = &gspca_dev->cam;

	cam->cam_mode = vga_mode;
	cam->nmodes = ARRAY_SIZE(vga_mode);
	cam->input_flags = V4L2_IN_ST_VFLIP;

	return 0;
}

static void setcontrast(struct gspca_dev *gspca_dev, s32 val)
{
	reg_w(gspca_dev, 0xff, 0x04);
	reg_w(gspca_dev, 0x10, val);
	/* load registers to sensor (Bit 0, auto clear) */
	reg_w(gspca_dev, 0x11, 0x01);
}

static void setgain(struct gspca_dev *gspca_dev, s32 val)
{
	reg_w(gspca_dev, 0xff, 0x04);			/* page 4 */
	reg_w(gspca_dev, 0x0e, 0x00);
	reg_w(gspca_dev, 0x0f, gspca_dev->gain->maximum - val + 1);

	/* load registers to sensor (Bit 0, auto clear) */
	reg_w(gspca_dev, 0x11, 0x01);
}

static void setexposure(struct gspca_dev *gspca_dev, s32 val)
{
	reg_w(gspca_dev, 0xff, 0x04);			/* page 4 */
	reg_w(gspca_dev, 0x02, val);

	/* load registers to sensor (Bit 0, auto clear) */
	reg_w(gspca_dev, 0x11, 0x01);

	/*
	 * Page 1 register 8 must always be 0x08 except when not in
	 *  640x480 mode and page 4 reg 2 <= 3 then it must be 9
	 */
	reg_w(gspca_dev, 0xff, 0x01);
	if (gspca_dev->pixfmt.width != 640 && val <= 3)
		reg_w(gspca_dev, 0x08, 0x09);
	else
		reg_w(gspca_dev, 0x08, 0x08);

	/*
	 * Page1 register 80 sets the compression balance, normally we
	 * want / use 0x1c, but for 640x480@30fps we must allow the
	 * camera to use higher compression or we may run out of
	 * bandwidth.
	 */
	if (gspca_dev->pixfmt.width == 640 && val == 2)
		reg_w(gspca_dev, 0x80, 0x01);
	else
		reg_w(gspca_dev, 0x80, 0x1c);

	/* load registers to sensor (Bit 0, auto clear) */
	reg_w(gspca_dev, 0x11, 0x01);
}

static void sethvflip(struct gspca_dev *gspca_dev, s32 hflip, s32 vflip)
{
	__u8 data;

	reg_w(gspca_dev, 0xff, 0x04);			/* page 4 */
	data = (hflip ? 0x04 : 0x00) |
	       (vflip ? 0x08 : 0x00);
	reg_w(gspca_dev, 0x21, data);

	/* load registers to sensor (Bit 0, auto clear) */
	reg_w(gspca_dev, 0x11, 0x01);
}

/* this function is called at probe and resume time for pac7311 */
static int sd_init(struct gspca_dev *gspca_dev)
{
	reg_w_seq(gspca_dev, init_7311, sizeof(init_7311)/2);
	return gspca_dev->usb_err;
}

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

	gspca_dev->usb_err = 0;

	if (ctrl->id == V4L2_CID_AUTOGAIN && ctrl->is_new && ctrl->val) {
		/* when switching to autogain set defaults to make sure
		   we are on a valid point of the autogain gain /
		   exposure knee graph, and give this change time to
		   take effect before doing autogain. */
		gspca_dev->exposure->val    = PAC7311_EXPOSURE_DEFAULT;
		gspca_dev->gain->val        = PAC7311_GAIN_DEFAULT;
		sd->autogain_ignore_frames  = PAC_AUTOGAIN_IGNORE_FRAMES;
	}

	if (!gspca_dev->streaming)
		return 0;

	switch (ctrl->id) {
	case V4L2_CID_CONTRAST:
		setcontrast(gspca_dev, ctrl->val);
		break;
	case V4L2_CID_AUTOGAIN:
		if (gspca_dev->exposure->is_new || (ctrl->is_new && ctrl->val))
			setexposure(gspca_dev, gspca_dev->exposure->val);
		if (gspca_dev->gain->is_new || (ctrl->is_new && ctrl->val))
			setgain(gspca_dev, gspca_dev->gain->val);
		break;
	case V4L2_CID_HFLIP:
		sethvflip(gspca_dev, sd->hflip->val, 1);
		break;
	default:
		return -EINVAL;
	}
	return gspca_dev->usb_err;
}

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

/* this function is called at probe time */
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, 5);

	sd->contrast = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
					V4L2_CID_CONTRAST, 0, 15, 1, 7);
	gspca_dev->autogain = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
					V4L2_CID_AUTOGAIN, 0, 1, 1, 1);
	gspca_dev->exposure = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
					V4L2_CID_EXPOSURE, 2, 63, 1,
					PAC7311_EXPOSURE_DEFAULT);
	gspca_dev->gain = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
					V4L2_CID_GAIN, 0, 244, 1,
					PAC7311_GAIN_DEFAULT);
	sd->hflip = v4l2_ctrl_new_std(hdl, &sd_ctrl_ops,
		V4L2_CID_HFLIP, 0, 1, 1, 0);

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

	v4l2_ctrl_auto_cluster(3, &gspca_dev->autogain, 0, false);
	return 0;
}

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

	sd->sof_read = 0;

	reg_w_var(gspca_dev, start_7311,
		page4_7311, sizeof(page4_7311));
	setcontrast(gspca_dev, v4l2_ctrl_g_ctrl(sd->contrast));
	setgain(gspca_dev, v4l2_ctrl_g_ctrl(gspca_dev->gain));
	setexposure(gspca_dev, v4l2_ctrl_g_ctrl(gspca_dev->exposure));
	sethvflip(gspca_dev, v4l2_ctrl_g_ctrl(sd->hflip), 1);

	/* set correct resolution */
	switch (gspca_dev->cam.cam_mode[(int) gspca_dev->curr_mode].priv) {
	case 2:					/* 160x120 */
		reg_w(gspca_dev, 0xff, 0x01);
		reg_w(gspca_dev, 0x17, 0x20);
		reg_w(gspca_dev, 0x87, 0x10);
		break;
	case 1:					/* 320x240 */
		reg_w(gspca_dev, 0xff, 0x01);
		reg_w(gspca_dev, 0x17, 0x30);
		reg_w(gspca_dev, 0x87, 0x11);
		break;
	case 0:					/* 640x480 */
		reg_w(gspca_dev, 0xff, 0x01);
		reg_w(gspca_dev, 0x17, 0x00);
		reg_w(gspca_dev, 0x87, 0x12);
		break;
	}

	sd->sof_read = 0;
	sd->autogain_ignore_frames = 0;
	atomic_set(&sd->avg_lum, -1);

	/* start stream */
	reg_w(gspca_dev, 0xff, 0x01);
	reg_w(gspca_dev, 0x78, 0x05);

	return gspca_dev->usb_err;
}

static void sd_stopN(struct gspca_dev *gspca_dev)
{
	reg_w(gspca_dev, 0xff, 0x04);
	reg_w(gspca_dev, 0x27, 0x80);
	reg_w(gspca_dev, 0x28, 0xca);
	reg_w(gspca_dev, 0x29, 0x53);
	reg_w(gspca_dev, 0x2a, 0x0e);
	reg_w(gspca_dev, 0xff, 0x01);
	reg_w(gspca_dev, 0x3e, 0x20);
	reg_w(gspca_dev, 0x78, 0x44); /* Bit_0=start stream, Bit_6=LED */
	reg_w(gspca_dev, 0x78, 0x44); /* Bit_0=start stream, Bit_6=LED */
	reg_w(gspca_dev, 0x78, 0x44); /* Bit_0=start stream, Bit_6=LED */
}

static void do_autogain(struct gspca_dev *gspca_dev)
{
	struct sd *sd = (struct sd *) gspca_dev;
	int avg_lum = atomic_read(&sd->avg_lum);
	int desired_lum, deadzone;

	if (avg_lum == -1)
		return;

	desired_lum = 170;
	deadzone = 20;

	if (sd->autogain_ignore_frames > 0)
		sd->autogain_ignore_frames--;
	else if (gspca_coarse_grained_expo_autogain(gspca_dev, avg_lum,
						    desired_lum, deadzone))
		sd->autogain_ignore_frames = PAC_AUTOGAIN_IGNORE_FRAMES;
}

/* JPEG header, part 1 */
static const unsigned char pac_jpeg_header1[] = {
  0xff, 0xd8,		/* SOI: Start of Image */

  0xff, 0xc0,		/* SOF0: Start of Frame (Baseline DCT) */
  0x00, 0x11,		/* length = 17 bytes (including this length field) */
  0x08			/* Precision: 8 */
  /* 2 bytes is placed here: number of image lines */
  /* 2 bytes is placed here: samples per line */
};

/* JPEG header, continued */
static const unsigned char pac_jpeg_header2[] = {
  0x03,			/* Number of image components: 3 */
  0x01, 0x21, 0x00,	/* ID=1, Subsampling 1x1, Quantization table: 0 */
  0x02, 0x11, 0x01,	/* ID=2, Subsampling 2x1, Quantization table: 1 */
  0x03, 0x11, 0x01,	/* ID=3, Subsampling 2x1, Quantization table: 1 */

  0xff, 0xda,		/* SOS: Start Of Scan */
  0x00, 0x0c,		/* length = 12 bytes (including this length field) */
  0x03,			/* number of components: 3 */
  0x01, 0x00,		/* selector 1, table 0x00 */
  0x02, 0x11,		/* selector 2, table 0x11 */
  0x03, 0x11,		/* selector 3, table 0x11 */
  0x00, 0x3f,		/* Spectral selection: 0 .. 63 */
  0x00			/* Successive approximation: 0 */
};

static void pac_start_frame(struct gspca_dev *gspca_dev,
		__u16 lines, __u16 samples_per_line)
{
	unsigned char tmpbuf[4];

	gspca_frame_add(gspca_dev, FIRST_PACKET,
		pac_jpeg_header1, sizeof(pac_jpeg_header1));

	tmpbuf[0] = lines >> 8;
	tmpbuf[1] = lines & 0xff;
	tmpbuf[2] = samples_per_line >> 8;
	tmpbuf[3] = samples_per_line & 0xff;

	gspca_frame_add(gspca_dev, INTER_PACKET,
		tmpbuf, sizeof(tmpbuf));
	gspca_frame_add(gspca_dev, INTER_PACKET,
		pac_jpeg_header2, sizeof(pac_jpeg_header2));
}

/* this function is run at interrupt level */
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;
	u8 *image;
	unsigned char *sof;

	sof = pac_find_sof(gspca_dev, &sd->sof_read, data, len);
	if (sof) {
		int n, lum_offset, footer_length;

		/*
		 * 6 bytes after the FF D9 EOF marker a number of lumination
		 * bytes are send corresponding to different parts of the
		 * image, the 14th and 15th byte after the EOF seem to
		 * correspond to the center of the image.
		 */
		lum_offset = 24 + sizeof pac_sof_marker;
		footer_length = 26;

		/* Finish decoding current frame */
		n = (sof - data) - (footer_length + sizeof pac_sof_marker);
		if (n < 0) {
			gspca_dev->image_len += n;
			n = 0;
		} else {
			gspca_frame_add(gspca_dev, INTER_PACKET, data, n);
		}
		image = gspca_dev->image;
		if (image != NULL
		 && image[gspca_dev->image_len - 2] == 0xff
		 && image[gspca_dev->image_len - 1] == 0xd9)
			gspca_frame_add(gspca_dev, LAST_PACKET, NULL, 0);

		n = sof - data;
		len -= n;
		data = sof;

		/* Get average lumination */
		if (gspca_dev->last_packet_type == LAST_PACKET &&
				n >= lum_offset)
			atomic_set(&sd->avg_lum, data[-lum_offset] +
						data[-lum_offset + 1]);
		else
			atomic_set(&sd->avg_lum, -1);

		/* Start the new frame with the jpeg header */
		pac_start_frame(gspca_dev,
			gspca_dev->pixfmt.height, gspca_dev->pixfmt.width);
	}
	gspca_frame_add(gspca_dev, INTER_PACKET, data, len);
}

#if IS_ENABLED(CONFIG_INPUT)
static int sd_int_pkt_scan(struct gspca_dev *gspca_dev,
			u8 *data,		/* interrupt packet data */
			int len)		/* interrupt packet length */
{
	int ret = -EINVAL;
	u8 data0, data1;

	if (len == 2) {
		data0 = data[0];
		data1 = data[1];
		if ((data0 == 0x00 && data1 == 0x11) ||
		    (data0 == 0x22 && data1 == 0x33) ||
		    (data0 == 0x44 && data1 == 0x55) ||
		    (data0 == 0x66 && data1 == 0x77) ||
		    (data0 == 0x88 && data1 == 0x99) ||
		    (data0 == 0xaa && data1 == 0xbb) ||
		    (data0 == 0xcc && data1 == 0xdd) ||
		    (data0 == 0xee && data1 == 0xff)) {
			input_report_key(gspca_dev->input_dev, KEY_CAMERA, 1);
			input_sync(gspca_dev->input_dev);
			input_report_key(gspca_dev->input_dev, KEY_CAMERA, 0);
			input_sync(gspca_dev->input_dev);
			ret = 0;
		}
	}

	return ret;
}
#endif

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 = do_autogain,
#if IS_ENABLED(CONFIG_INPUT)
	.int_pkt_scan = sd_int_pkt_scan,
#endif
};

/* -- module initialisation -- */
static const struct usb_device_id device_table[] = {
	{USB_DEVICE(0x093a, 0x2600)},
	{USB_DEVICE(0x093a, 0x2601)},
	{USB_DEVICE(0x093a, 0x2603)},
	{USB_DEVICE(0x093a, 0x2608)},
	{USB_DEVICE(0x093a, 0x260e)},
	{USB_DEVICE(0x093a, 0x260f)},
	{}
};
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);