1 /*
2  * STK1160 driver
3  *
4  * Copyright (C) 2012 Ezequiel Garcia
5  * <elezegarcia--a.t--gmail.com>
6  *
7  * Based on Easycap driver by R.M. Thomas
8  *	Copyright (C) 2010 R.M. Thomas
9  *	<rmthomas--a.t--sciolus.org>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  */
22 
23 #include <linux/module.h>
24 #include <linux/usb.h>
25 #include <linux/mm.h>
26 #include <linux/slab.h>
27 
28 #include <linux/videodev2.h>
29 #include <media/v4l2-device.h>
30 #include <media/v4l2-common.h>
31 #include <media/v4l2-ioctl.h>
32 #include <media/v4l2-fh.h>
33 #include <media/v4l2-event.h>
34 #include <media/videobuf2-vmalloc.h>
35 
36 #include <media/i2c/saa7115.h>
37 
38 #include "stk1160.h"
39 #include "stk1160-reg.h"
40 
41 static bool keep_buffers;
42 module_param(keep_buffers, bool, 0644);
43 MODULE_PARM_DESC(keep_buffers, "don't release buffers upon stop streaming");
44 
45 enum stk1160_decimate_mode {
46 	STK1160_DECIMATE_MORE_THAN_HALF,
47 	STK1160_DECIMATE_LESS_THAN_HALF,
48 };
49 
50 struct stk1160_decimate_ctrl {
51 	bool col_en, row_en;
52 	enum stk1160_decimate_mode col_mode, row_mode;
53 	unsigned int col_n, row_n;
54 };
55 
56 /* supported video standards */
57 static struct stk1160_fmt format[] = {
58 	{
59 		.name     = "16 bpp YUY2, 4:2:2, packed",
60 		.fourcc   = V4L2_PIX_FMT_UYVY,
61 		.depth    = 16,
62 	}
63 };
64 
65 /*
66  * Helper to find the next divisor that results in modulo being zero.
67  * This is required to guarantee valid decimation unit counts.
68  */
69 static unsigned int
70 div_round_integer(unsigned int x, unsigned int y)
71 {
72 	for (;; y++) {
73 		if (x % y == 0)
74 			return x / y;
75 	}
76 }
77 
78 static void stk1160_set_std(struct stk1160 *dev)
79 {
80 	int i;
81 
82 	static struct regval std525[] = {
83 
84 		/* 720x480 */
85 
86 		/* Frame start */
87 		{STK116_CFSPO_STX_L, 0x0000},
88 		{STK116_CFSPO_STX_H, 0x0000},
89 		{STK116_CFSPO_STY_L, 0x0003},
90 		{STK116_CFSPO_STY_H, 0x0000},
91 
92 		/* Frame end */
93 		{STK116_CFEPO_ENX_L, 0x05a0},
94 		{STK116_CFEPO_ENX_H, 0x0005},
95 		{STK116_CFEPO_ENY_L, 0x00f3},
96 		{STK116_CFEPO_ENY_H, 0x0000},
97 
98 		{0xffff, 0xffff}
99 	};
100 
101 	static struct regval std625[] = {
102 
103 		/* 720x576 */
104 
105 		/* TODO: Each line of frame has some junk at the end */
106 		/* Frame start */
107 		{STK116_CFSPO,   0x0000},
108 		{STK116_CFSPO+1, 0x0000},
109 		{STK116_CFSPO+2, 0x0001},
110 		{STK116_CFSPO+3, 0x0000},
111 
112 		/* Frame end */
113 		{STK116_CFEPO,   0x05a0},
114 		{STK116_CFEPO+1, 0x0005},
115 		{STK116_CFEPO+2, 0x0121},
116 		{STK116_CFEPO+3, 0x0001},
117 
118 		{0xffff, 0xffff}
119 	};
120 
121 	if (dev->norm & V4L2_STD_525_60) {
122 		stk1160_dbg("registers to NTSC like standard\n");
123 		for (i = 0; std525[i].reg != 0xffff; i++)
124 			stk1160_write_reg(dev, std525[i].reg, std525[i].val);
125 	} else {
126 		stk1160_dbg("registers to PAL like standard\n");
127 		for (i = 0; std625[i].reg != 0xffff; i++)
128 			stk1160_write_reg(dev, std625[i].reg, std625[i].val);
129 	}
130 
131 }
132 
133 static void stk1160_set_fmt(struct stk1160 *dev,
134 			    struct stk1160_decimate_ctrl *ctrl)
135 {
136 	u32 val = 0;
137 
138 	if (ctrl) {
139 		/*
140 		 * Since the format is UYVY, the device must skip or send
141 		 * a number of rows/columns multiple of four. This way, the
142 		 * colour format is preserved. The STK1160_DEC_UNIT_SIZE bit
143 		 * does exactly this.
144 		 */
145 		val |= STK1160_DEC_UNIT_SIZE;
146 		val |= ctrl->col_en ? STK1160_H_DEC_EN : 0;
147 		val |= ctrl->row_en ? STK1160_V_DEC_EN : 0;
148 		val |= ctrl->col_mode ==
149 			STK1160_DECIMATE_MORE_THAN_HALF ?
150 			STK1160_H_DEC_MODE : 0;
151 		val |= ctrl->row_mode ==
152 			STK1160_DECIMATE_MORE_THAN_HALF ?
153 			STK1160_V_DEC_MODE : 0;
154 
155 		/* Horizontal count units */
156 		stk1160_write_reg(dev, STK1160_DMCTRL_H_UNITS, ctrl->col_n);
157 		/* Vertical count units */
158 		stk1160_write_reg(dev, STK1160_DMCTRL_V_UNITS, ctrl->row_n);
159 
160 		stk1160_dbg("decimate 0x%x, column units %d, row units %d\n",
161 			    val, ctrl->col_n, ctrl->row_n);
162 	}
163 
164 	/* Decimation control */
165 	stk1160_write_reg(dev, STK1160_DMCTRL, val);
166 }
167 
168 /*
169  * Set a new alternate setting.
170  * Returns true is dev->max_pkt_size has changed, false otherwise.
171  */
172 static bool stk1160_set_alternate(struct stk1160 *dev)
173 {
174 	int i, prev_alt = dev->alt;
175 	unsigned int min_pkt_size;
176 	bool new_pkt_size;
177 
178 	/*
179 	 * If we don't set right alternate,
180 	 * then we will get a green screen with junk.
181 	 */
182 	min_pkt_size = STK1160_MIN_PKT_SIZE;
183 
184 	for (i = 0; i < dev->num_alt; i++) {
185 		/* stop when the selected alt setting offers enough bandwidth */
186 		if (dev->alt_max_pkt_size[i] >= min_pkt_size) {
187 			dev->alt = i;
188 			break;
189 		/*
190 		 * otherwise make sure that we end up with the maximum bandwidth
191 		 * because the min_pkt_size equation might be wrong...
192 		 */
193 		} else if (dev->alt_max_pkt_size[i] >
194 			   dev->alt_max_pkt_size[dev->alt])
195 			dev->alt = i;
196 	}
197 
198 	stk1160_dbg("setting alternate %d\n", dev->alt);
199 
200 	if (dev->alt != prev_alt) {
201 		stk1160_dbg("minimum isoc packet size: %u (alt=%d)\n",
202 				min_pkt_size, dev->alt);
203 		stk1160_dbg("setting alt %d with wMaxPacketSize=%u\n",
204 			       dev->alt, dev->alt_max_pkt_size[dev->alt]);
205 		usb_set_interface(dev->udev, 0, dev->alt);
206 	}
207 
208 	new_pkt_size = dev->max_pkt_size != dev->alt_max_pkt_size[dev->alt];
209 	dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
210 
211 	return new_pkt_size;
212 }
213 
214 static int stk1160_start_streaming(struct stk1160 *dev)
215 {
216 	bool new_pkt_size;
217 	int rc = 0;
218 	int i;
219 
220 	/* Check device presence */
221 	if (!dev->udev)
222 		return -ENODEV;
223 
224 	if (mutex_lock_interruptible(&dev->v4l_lock))
225 		return -ERESTARTSYS;
226 	/*
227 	 * For some reason it is mandatory to set alternate *first*
228 	 * and only *then* initialize isoc urbs.
229 	 * Someone please explain me why ;)
230 	 */
231 	new_pkt_size = stk1160_set_alternate(dev);
232 
233 	/*
234 	 * We (re)allocate isoc urbs if:
235 	 * there is no allocated isoc urbs, OR
236 	 * a new dev->max_pkt_size is detected
237 	 */
238 	if (!dev->isoc_ctl.num_bufs || new_pkt_size) {
239 		rc = stk1160_alloc_isoc(dev);
240 		if (rc < 0)
241 			goto out_stop_hw;
242 	}
243 
244 	/* submit urbs and enables IRQ */
245 	for (i = 0; i < dev->isoc_ctl.num_bufs; i++) {
246 		rc = usb_submit_urb(dev->isoc_ctl.urb[i], GFP_KERNEL);
247 		if (rc) {
248 			stk1160_err("cannot submit urb[%d] (%d)\n", i, rc);
249 			goto out_uninit;
250 		}
251 	}
252 
253 	/* Start saa711x */
254 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_stream, 1);
255 
256 	dev->sequence = 0;
257 
258 	/* Start stk1160 */
259 	stk1160_write_reg(dev, STK1160_DCTRL, 0xb3);
260 	stk1160_write_reg(dev, STK1160_DCTRL+3, 0x00);
261 
262 	stk1160_dbg("streaming started\n");
263 
264 	mutex_unlock(&dev->v4l_lock);
265 
266 	return 0;
267 
268 out_uninit:
269 	stk1160_uninit_isoc(dev);
270 out_stop_hw:
271 	usb_set_interface(dev->udev, 0, 0);
272 	stk1160_clear_queue(dev);
273 
274 	mutex_unlock(&dev->v4l_lock);
275 
276 	return rc;
277 }
278 
279 /* Must be called with v4l_lock hold */
280 static void stk1160_stop_hw(struct stk1160 *dev)
281 {
282 	/* If the device is not physically present, there is nothing to do */
283 	if (!dev->udev)
284 		return;
285 
286 	/* set alternate 0 */
287 	dev->alt = 0;
288 	stk1160_dbg("setting alternate %d\n", dev->alt);
289 	usb_set_interface(dev->udev, 0, 0);
290 
291 	/* Stop stk1160 */
292 	stk1160_write_reg(dev, STK1160_DCTRL, 0x00);
293 	stk1160_write_reg(dev, STK1160_DCTRL+3, 0x00);
294 
295 	/* Stop saa711x */
296 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_stream, 0);
297 }
298 
299 static int stk1160_stop_streaming(struct stk1160 *dev)
300 {
301 	if (mutex_lock_interruptible(&dev->v4l_lock))
302 		return -ERESTARTSYS;
303 
304 	/*
305 	 * Once URBs are cancelled, the URB complete handler
306 	 * won't be running. This is required to safely release the
307 	 * current buffer (dev->isoc_ctl.buf).
308 	 */
309 	stk1160_cancel_isoc(dev);
310 
311 	/*
312 	 * It is possible to keep buffers around using a module parameter.
313 	 * This is intended to avoid memory fragmentation.
314 	 */
315 	if (!keep_buffers)
316 		stk1160_free_isoc(dev);
317 
318 	stk1160_stop_hw(dev);
319 
320 	stk1160_clear_queue(dev);
321 
322 	stk1160_dbg("streaming stopped\n");
323 
324 	mutex_unlock(&dev->v4l_lock);
325 
326 	return 0;
327 }
328 
329 static const struct v4l2_file_operations stk1160_fops = {
330 	.owner = THIS_MODULE,
331 	.open = v4l2_fh_open,
332 	.release = vb2_fop_release,
333 	.read = vb2_fop_read,
334 	.poll = vb2_fop_poll,
335 	.mmap = vb2_fop_mmap,
336 	.unlocked_ioctl = video_ioctl2,
337 };
338 
339 /*
340  * vidioc ioctls
341  */
342 static int vidioc_querycap(struct file *file,
343 		void *priv, struct v4l2_capability *cap)
344 {
345 	struct stk1160 *dev = video_drvdata(file);
346 
347 	strscpy(cap->driver, "stk1160", sizeof(cap->driver));
348 	strscpy(cap->card, "stk1160", sizeof(cap->card));
349 	usb_make_path(dev->udev, cap->bus_info, sizeof(cap->bus_info));
350 	cap->device_caps =
351 		V4L2_CAP_VIDEO_CAPTURE |
352 		V4L2_CAP_STREAMING |
353 		V4L2_CAP_READWRITE;
354 	cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
355 	return 0;
356 }
357 
358 static int vidioc_enum_fmt_vid_cap(struct file *file, void  *priv,
359 		struct v4l2_fmtdesc *f)
360 {
361 	if (f->index != 0)
362 		return -EINVAL;
363 
364 	strscpy(f->description, format[f->index].name, sizeof(f->description));
365 	f->pixelformat = format[f->index].fourcc;
366 	return 0;
367 }
368 
369 static int vidioc_g_fmt_vid_cap(struct file *file, void *priv,
370 					struct v4l2_format *f)
371 {
372 	struct stk1160 *dev = video_drvdata(file);
373 
374 	f->fmt.pix.width = dev->width;
375 	f->fmt.pix.height = dev->height;
376 	f->fmt.pix.field = V4L2_FIELD_INTERLACED;
377 	f->fmt.pix.pixelformat = dev->fmt->fourcc;
378 	f->fmt.pix.bytesperline = dev->width * 2;
379 	f->fmt.pix.sizeimage = dev->height * f->fmt.pix.bytesperline;
380 	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
381 
382 	return 0;
383 }
384 
385 static int stk1160_try_fmt(struct stk1160 *dev, struct v4l2_format *f,
386 			    struct stk1160_decimate_ctrl *ctrl)
387 {
388 	unsigned int width, height;
389 	unsigned int base_width, base_height;
390 	unsigned int col_n, row_n;
391 	enum stk1160_decimate_mode col_mode, row_mode;
392 	bool col_en, row_en;
393 
394 	base_width = 720;
395 	base_height = (dev->norm & V4L2_STD_525_60) ? 480 : 576;
396 
397 	/* Minimum width and height is 5% the frame size */
398 	width = clamp_t(unsigned int, f->fmt.pix.width,
399 			base_width / 20, base_width);
400 	height = clamp_t(unsigned int, f->fmt.pix.height,
401 			base_height / 20, base_height);
402 
403 	/* Let's set default no decimation values */
404 	col_n = 0;
405 	row_n = 0;
406 	col_en = false;
407 	row_en = false;
408 	f->fmt.pix.width = base_width;
409 	f->fmt.pix.height = base_height;
410 	row_mode = STK1160_DECIMATE_LESS_THAN_HALF;
411 	col_mode = STK1160_DECIMATE_LESS_THAN_HALF;
412 
413 	if (width < base_width && width > base_width / 2) {
414 		/*
415 		 * The device will send count units for each
416 		 * unit skipped. This means count unit is:
417 		 *
418 		 * n = width / (frame width - width)
419 		 *
420 		 * And the width is:
421 		 *
422 		 * width = (n / n + 1) * frame width
423 		 */
424 		col_n = div_round_integer(width, base_width - width);
425 		if (col_n > 0 && col_n <= 255) {
426 			col_en = true;
427 			col_mode = STK1160_DECIMATE_LESS_THAN_HALF;
428 			f->fmt.pix.width = (base_width * col_n) / (col_n + 1);
429 		}
430 
431 	} else if (width <= base_width / 2) {
432 
433 		/*
434 		 * The device will skip count units for each
435 		 * unit sent. This means count is:
436 		 *
437 		 * n = (frame width / width) - 1
438 		 *
439 		 * And the width is:
440 		 *
441 		 * width = frame width / (n + 1)
442 		 */
443 		col_n = div_round_integer(base_width, width) - 1;
444 		if (col_n > 0 && col_n <= 255) {
445 			col_en = true;
446 			col_mode = STK1160_DECIMATE_MORE_THAN_HALF;
447 			f->fmt.pix.width = base_width / (col_n + 1);
448 		}
449 	}
450 
451 	if (height < base_height && height > base_height / 2) {
452 		row_n = div_round_integer(height, base_height - height);
453 		if (row_n > 0 && row_n <= 255) {
454 			row_en = true;
455 			row_mode = STK1160_DECIMATE_LESS_THAN_HALF;
456 			f->fmt.pix.height = (base_height * row_n) / (row_n + 1);
457 		}
458 
459 	} else if (height <= base_height / 2) {
460 		row_n = div_round_integer(base_height, height) - 1;
461 		if (row_n > 0 && row_n <= 255) {
462 			row_en = true;
463 			row_mode = STK1160_DECIMATE_MORE_THAN_HALF;
464 			f->fmt.pix.height = base_height / (row_n + 1);
465 		}
466 	}
467 
468 	f->fmt.pix.pixelformat = dev->fmt->fourcc;
469 	f->fmt.pix.field = V4L2_FIELD_INTERLACED;
470 	f->fmt.pix.bytesperline = f->fmt.pix.width * 2;
471 	f->fmt.pix.sizeimage = f->fmt.pix.height * f->fmt.pix.bytesperline;
472 	f->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
473 
474 	if (ctrl) {
475 		ctrl->col_en = col_en;
476 		ctrl->col_n = col_n;
477 		ctrl->col_mode = col_mode;
478 		ctrl->row_en = row_en;
479 		ctrl->row_n = row_n;
480 		ctrl->row_mode = row_mode;
481 	}
482 
483 	stk1160_dbg("width %d, height %d\n",
484 		    f->fmt.pix.width, f->fmt.pix.height);
485 	return 0;
486 }
487 
488 static int vidioc_try_fmt_vid_cap(struct file *file, void *priv,
489 				  struct v4l2_format *f)
490 {
491 	struct stk1160 *dev = video_drvdata(file);
492 
493 	return stk1160_try_fmt(dev, f, NULL);
494 }
495 
496 static int vidioc_s_fmt_vid_cap(struct file *file, void *priv,
497 					struct v4l2_format *f)
498 {
499 	struct stk1160 *dev = video_drvdata(file);
500 	struct vb2_queue *q = &dev->vb_vidq;
501 	struct stk1160_decimate_ctrl ctrl;
502 	int rc;
503 
504 	if (vb2_is_busy(q))
505 		return -EBUSY;
506 
507 	rc = stk1160_try_fmt(dev, f, &ctrl);
508 	if (rc < 0)
509 		return rc;
510 	dev->width = f->fmt.pix.width;
511 	dev->height = f->fmt.pix.height;
512 	stk1160_set_fmt(dev, &ctrl);
513 
514 	return 0;
515 }
516 
517 static int vidioc_querystd(struct file *file, void *priv, v4l2_std_id *norm)
518 {
519 	struct stk1160 *dev = video_drvdata(file);
520 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, querystd, norm);
521 	return 0;
522 }
523 
524 static int vidioc_g_std(struct file *file, void *priv, v4l2_std_id *norm)
525 {
526 	struct stk1160 *dev = video_drvdata(file);
527 
528 	*norm = dev->norm;
529 	return 0;
530 }
531 
532 static int vidioc_s_std(struct file *file, void *priv, v4l2_std_id norm)
533 {
534 	struct stk1160 *dev = video_drvdata(file);
535 	struct vb2_queue *q = &dev->vb_vidq;
536 
537 	if (dev->norm == norm)
538 		return 0;
539 
540 	if (vb2_is_busy(q))
541 		return -EBUSY;
542 
543 	/* Check device presence */
544 	if (!dev->udev)
545 		return -ENODEV;
546 
547 	/* We need to set this now, before we call stk1160_set_std */
548 	dev->width = 720;
549 	dev->height = (norm & V4L2_STD_525_60) ? 480 : 576;
550 	dev->norm = norm;
551 
552 	stk1160_set_std(dev);
553 
554 	/* Calling with NULL disables frame decimation */
555 	stk1160_set_fmt(dev, NULL);
556 
557 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_std,
558 			dev->norm);
559 
560 	return 0;
561 }
562 
563 
564 static int vidioc_enum_input(struct file *file, void *priv,
565 				struct v4l2_input *i)
566 {
567 	struct stk1160 *dev = video_drvdata(file);
568 
569 	if (i->index > STK1160_MAX_INPUT)
570 		return -EINVAL;
571 
572 	/* S-Video special handling */
573 	if (i->index == STK1160_SVIDEO_INPUT)
574 		sprintf(i->name, "S-Video");
575 	else
576 		sprintf(i->name, "Composite%d", i->index);
577 
578 	i->type = V4L2_INPUT_TYPE_CAMERA;
579 	i->std = dev->vdev.tvnorms;
580 	return 0;
581 }
582 
583 static int vidioc_g_input(struct file *file, void *priv, unsigned int *i)
584 {
585 	struct stk1160 *dev = video_drvdata(file);
586 	*i = dev->ctl_input;
587 	return 0;
588 }
589 
590 static int vidioc_s_input(struct file *file, void *priv, unsigned int i)
591 {
592 	struct stk1160 *dev = video_drvdata(file);
593 
594 	if (i > STK1160_MAX_INPUT)
595 		return -EINVAL;
596 
597 	dev->ctl_input = i;
598 
599 	stk1160_select_input(dev);
600 
601 	return 0;
602 }
603 
604 #ifdef CONFIG_VIDEO_ADV_DEBUG
605 static int vidioc_g_register(struct file *file, void *priv,
606 			     struct v4l2_dbg_register *reg)
607 {
608 	struct stk1160 *dev = video_drvdata(file);
609 	int rc;
610 	u8 val;
611 
612 	/* Match host */
613 	rc = stk1160_read_reg(dev, reg->reg, &val);
614 	reg->val = val;
615 	reg->size = 1;
616 
617 	return rc;
618 }
619 
620 static int vidioc_s_register(struct file *file, void *priv,
621 			     const struct v4l2_dbg_register *reg)
622 {
623 	struct stk1160 *dev = video_drvdata(file);
624 
625 	/* Match host */
626 	return stk1160_write_reg(dev, reg->reg, reg->val);
627 }
628 #endif
629 
630 static const struct v4l2_ioctl_ops stk1160_ioctl_ops = {
631 	.vidioc_querycap      = vidioc_querycap,
632 	.vidioc_enum_fmt_vid_cap  = vidioc_enum_fmt_vid_cap,
633 	.vidioc_g_fmt_vid_cap     = vidioc_g_fmt_vid_cap,
634 	.vidioc_try_fmt_vid_cap   = vidioc_try_fmt_vid_cap,
635 	.vidioc_s_fmt_vid_cap     = vidioc_s_fmt_vid_cap,
636 	.vidioc_querystd      = vidioc_querystd,
637 	.vidioc_g_std         = vidioc_g_std,
638 	.vidioc_s_std         = vidioc_s_std,
639 	.vidioc_enum_input    = vidioc_enum_input,
640 	.vidioc_g_input       = vidioc_g_input,
641 	.vidioc_s_input       = vidioc_s_input,
642 
643 	/* vb2 takes care of these */
644 	.vidioc_reqbufs       = vb2_ioctl_reqbufs,
645 	.vidioc_querybuf      = vb2_ioctl_querybuf,
646 	.vidioc_qbuf          = vb2_ioctl_qbuf,
647 	.vidioc_dqbuf         = vb2_ioctl_dqbuf,
648 	.vidioc_streamon      = vb2_ioctl_streamon,
649 	.vidioc_streamoff     = vb2_ioctl_streamoff,
650 	.vidioc_expbuf        = vb2_ioctl_expbuf,
651 
652 	.vidioc_log_status  = v4l2_ctrl_log_status,
653 	.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
654 	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
655 
656 #ifdef CONFIG_VIDEO_ADV_DEBUG
657 	.vidioc_g_register = vidioc_g_register,
658 	.vidioc_s_register = vidioc_s_register,
659 #endif
660 };
661 
662 /********************************************************************/
663 
664 /*
665  * Videobuf2 operations
666  */
667 static int queue_setup(struct vb2_queue *vq,
668 				unsigned int *nbuffers, unsigned int *nplanes,
669 				unsigned int sizes[], struct device *alloc_devs[])
670 {
671 	struct stk1160 *dev = vb2_get_drv_priv(vq);
672 	unsigned long size;
673 
674 	size = dev->width * dev->height * 2;
675 
676 	/*
677 	 * Here we can change the number of buffers being requested.
678 	 * So, we set a minimum and a maximum like this:
679 	 */
680 	*nbuffers = clamp_t(unsigned int, *nbuffers,
681 			STK1160_MIN_VIDEO_BUFFERS, STK1160_MAX_VIDEO_BUFFERS);
682 
683 	if (*nplanes)
684 		return sizes[0] < size ? -EINVAL : 0;
685 
686 	/* This means a packed colorformat */
687 	*nplanes = 1;
688 
689 	sizes[0] = size;
690 
691 	stk1160_dbg("%s: buffer count %d, each %ld bytes\n",
692 		    __func__, *nbuffers, size);
693 
694 	return 0;
695 }
696 
697 static void buffer_queue(struct vb2_buffer *vb)
698 {
699 	unsigned long flags;
700 	struct stk1160 *dev = vb2_get_drv_priv(vb->vb2_queue);
701 	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
702 	struct stk1160_buffer *buf =
703 		container_of(vbuf, struct stk1160_buffer, vb);
704 
705 	spin_lock_irqsave(&dev->buf_lock, flags);
706 	if (!dev->udev) {
707 		/*
708 		 * If the device is disconnected return the buffer to userspace
709 		 * directly. The next QBUF call will fail with -ENODEV.
710 		 */
711 		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
712 	} else {
713 
714 		buf->mem = vb2_plane_vaddr(vb, 0);
715 		buf->length = vb2_plane_size(vb, 0);
716 		buf->bytesused = 0;
717 		buf->pos = 0;
718 
719 		/*
720 		 * If buffer length is less from expected then we return
721 		 * the buffer to userspace directly.
722 		 */
723 		if (buf->length < dev->width * dev->height * 2)
724 			vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
725 		else
726 			list_add_tail(&buf->list, &dev->avail_bufs);
727 
728 	}
729 	spin_unlock_irqrestore(&dev->buf_lock, flags);
730 }
731 
732 static int start_streaming(struct vb2_queue *vq, unsigned int count)
733 {
734 	struct stk1160 *dev = vb2_get_drv_priv(vq);
735 	return stk1160_start_streaming(dev);
736 }
737 
738 /* abort streaming and wait for last buffer */
739 static void stop_streaming(struct vb2_queue *vq)
740 {
741 	struct stk1160 *dev = vb2_get_drv_priv(vq);
742 	stk1160_stop_streaming(dev);
743 }
744 
745 static const struct vb2_ops stk1160_video_qops = {
746 	.queue_setup		= queue_setup,
747 	.buf_queue		= buffer_queue,
748 	.start_streaming	= start_streaming,
749 	.stop_streaming		= stop_streaming,
750 	.wait_prepare		= vb2_ops_wait_prepare,
751 	.wait_finish		= vb2_ops_wait_finish,
752 };
753 
754 static const struct video_device v4l_template = {
755 	.name = "stk1160",
756 	.tvnorms = V4L2_STD_525_60 | V4L2_STD_625_50,
757 	.fops = &stk1160_fops,
758 	.ioctl_ops = &stk1160_ioctl_ops,
759 	.release = video_device_release_empty,
760 };
761 
762 /********************************************************************/
763 
764 /* Must be called with both v4l_lock and vb_queue_lock hold */
765 void stk1160_clear_queue(struct stk1160 *dev)
766 {
767 	struct stk1160_buffer *buf;
768 	unsigned long flags;
769 
770 	/* Release all active buffers */
771 	spin_lock_irqsave(&dev->buf_lock, flags);
772 	while (!list_empty(&dev->avail_bufs)) {
773 		buf = list_first_entry(&dev->avail_bufs,
774 			struct stk1160_buffer, list);
775 		list_del(&buf->list);
776 		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
777 		stk1160_dbg("buffer [%p/%d] aborted\n",
778 			    buf, buf->vb.vb2_buf.index);
779 	}
780 
781 	/* It's important to release the current buffer */
782 	if (dev->isoc_ctl.buf) {
783 		buf = dev->isoc_ctl.buf;
784 		dev->isoc_ctl.buf = NULL;
785 
786 		vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
787 		stk1160_dbg("buffer [%p/%d] aborted\n",
788 			    buf, buf->vb.vb2_buf.index);
789 	}
790 	spin_unlock_irqrestore(&dev->buf_lock, flags);
791 }
792 
793 int stk1160_vb2_setup(struct stk1160 *dev)
794 {
795 	int rc;
796 	struct vb2_queue *q;
797 
798 	q = &dev->vb_vidq;
799 	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
800 	q->io_modes = VB2_READ | VB2_MMAP | VB2_USERPTR | VB2_DMABUF;
801 	q->drv_priv = dev;
802 	q->buf_struct_size = sizeof(struct stk1160_buffer);
803 	q->ops = &stk1160_video_qops;
804 	q->mem_ops = &vb2_vmalloc_memops;
805 	q->lock = &dev->vb_queue_lock;
806 	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
807 
808 	rc = vb2_queue_init(q);
809 	if (rc < 0)
810 		return rc;
811 
812 	/* initialize video dma queue */
813 	INIT_LIST_HEAD(&dev->avail_bufs);
814 
815 	return 0;
816 }
817 
818 int stk1160_video_register(struct stk1160 *dev)
819 {
820 	int rc;
821 
822 	/* Initialize video_device with a template structure */
823 	dev->vdev = v4l_template;
824 	dev->vdev.queue = &dev->vb_vidq;
825 
826 	/*
827 	 * Provide mutexes for v4l2 core and for videobuf2 queue.
828 	 * It will be used to protect *only* v4l2 ioctls.
829 	 */
830 	dev->vdev.lock = &dev->v4l_lock;
831 
832 	/* This will be used to set video_device parent */
833 	dev->vdev.v4l2_dev = &dev->v4l2_dev;
834 
835 	/* NTSC is default */
836 	dev->norm = V4L2_STD_NTSC_M;
837 	dev->width = 720;
838 	dev->height = 480;
839 
840 	/* set default format */
841 	dev->fmt = &format[0];
842 	stk1160_set_std(dev);
843 
844 	v4l2_device_call_all(&dev->v4l2_dev, 0, video, s_std,
845 			dev->norm);
846 
847 	video_set_drvdata(&dev->vdev, dev);
848 	rc = video_register_device(&dev->vdev, VFL_TYPE_GRABBER, -1);
849 	if (rc < 0) {
850 		stk1160_err("video_register_device failed (%d)\n", rc);
851 		return rc;
852 	}
853 
854 	v4l2_info(&dev->v4l2_dev, "V4L2 device registered as %s\n",
855 		  video_device_node_name(&dev->vdev));
856 
857 	return 0;
858 }
859