vimc-capture.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * vimc-capture.c Virtual Media Controller Driver
  4 *
  5 * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
  6 */
  7
  8#include <media/v4l2-ioctl.h>
  9#include <media/videobuf2-core.h>
 10#include <media/videobuf2-dma-contig.h>
 11#include <media/videobuf2-vmalloc.h>
 12
 13#include "vimc-common.h"
 14#include "vimc-streamer.h"
 15
 16struct vimc_capture_device {
 17	struct vimc_ent_device ved;
 18	struct video_device vdev;
 19	struct v4l2_pix_format format;
 20	struct vb2_queue queue;
 21	struct list_head buf_list;
 22	/*
 23	 * NOTE: in a real driver, a spin lock must be used to access the
 24	 * queue because the frames are generated from a hardware interruption
 25	 * and the isr is not allowed to sleep.
 26	 * Even if it is not necessary a spinlock in the vimc driver, we
 27	 * use it here as a code reference
 28	 */
 29	spinlock_t qlock;
 30	struct mutex lock;
 31	u32 sequence;
 32	struct vimc_stream stream;
 33	struct media_pad pad;
 34};
 35
 36static const struct v4l2_pix_format fmt_default = {
 37	.width = 640,
 38	.height = 480,
 39	.pixelformat = V4L2_PIX_FMT_RGB24,
 40	.field = V4L2_FIELD_NONE,
 41	.colorspace = V4L2_COLORSPACE_SRGB,
 42};
 43
 44struct vimc_capture_buffer {
 45	/*
 46	 * struct vb2_v4l2_buffer must be the first element
 47	 * the videobuf2 framework will allocate this struct based on
 48	 * buf_struct_size and use the first sizeof(struct vb2_buffer) bytes of
 49	 * memory as a vb2_buffer
 50	 */
 51	struct vb2_v4l2_buffer vb2;
 52	struct list_head list;
 53};
 54
 55static int vimc_capture_querycap(struct file *file, void *priv,
 56			     struct v4l2_capability *cap)
 57{
 58	strscpy(cap->driver, VIMC_PDEV_NAME, sizeof(cap->driver));
 59	strscpy(cap->card, KBUILD_MODNAME, sizeof(cap->card));
 60
 61	return 0;
 62}
 63
 64static void vimc_capture_get_format(struct vimc_ent_device *ved,
 65				struct v4l2_pix_format *fmt)
 66{
 67	struct vimc_capture_device *vcapture = container_of(ved, struct vimc_capture_device,
 68						    ved);
 69
 70	*fmt = vcapture->format;
 71}
 72
 73static int vimc_capture_g_fmt_vid_cap(struct file *file, void *priv,
 74				  struct v4l2_format *f)
 75{
 76	struct vimc_capture_device *vcapture = video_drvdata(file);
 77
 78	f->fmt.pix = vcapture->format;
 79
 80	return 0;
 81}
 82
 83static int vimc_capture_try_fmt_vid_cap(struct file *file, void *priv,
 84				    struct v4l2_format *f)
 85{
 86	struct v4l2_pix_format *format = &f->fmt.pix;
 87	const struct vimc_pix_map *vpix;
 88
 89	format->width = clamp_t(u32, format->width, VIMC_FRAME_MIN_WIDTH,
 90				VIMC_FRAME_MAX_WIDTH) & ~1;
 91	format->height = clamp_t(u32, format->height, VIMC_FRAME_MIN_HEIGHT,
 92				 VIMC_FRAME_MAX_HEIGHT) & ~1;
 93
 94	/* Don't accept a pixelformat that is not on the table */
 95	vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
 96	if (!vpix) {
 97		format->pixelformat = fmt_default.pixelformat;
 98		vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
 99	}
100	/* TODO: Add support for custom bytesperline values */
101	format->bytesperline = format->width * vpix->bpp;
102	format->sizeimage = format->bytesperline * format->height;
103
104	if (format->field == V4L2_FIELD_ANY)
105		format->field = fmt_default.field;
106
107	vimc_colorimetry_clamp(format);
108
109	if (format->colorspace == V4L2_COLORSPACE_DEFAULT)
110		format->colorspace = fmt_default.colorspace;
111
112	return 0;
113}
114
115static int vimc_capture_s_fmt_vid_cap(struct file *file, void *priv,
116				  struct v4l2_format *f)
117{
118	struct vimc_capture_device *vcapture = video_drvdata(file);
119	int ret;
120
121	/* Do not change the format while stream is on */
122	if (vb2_is_busy(&vcapture->queue))
123		return -EBUSY;
124
125	ret = vimc_capture_try_fmt_vid_cap(file, priv, f);
126	if (ret)
127		return ret;
128
129	dev_dbg(vcapture->ved.dev, "%s: format update: "
130		"old:%dx%d (0x%x, %d, %d, %d, %d) "
131		"new:%dx%d (0x%x, %d, %d, %d, %d)\n", vcapture->vdev.name,
132		/* old */
133		vcapture->format.width, vcapture->format.height,
134		vcapture->format.pixelformat, vcapture->format.colorspace,
135		vcapture->format.quantization, vcapture->format.xfer_func,
136		vcapture->format.ycbcr_enc,
137		/* new */
138		f->fmt.pix.width, f->fmt.pix.height,
139		f->fmt.pix.pixelformat,	f->fmt.pix.colorspace,
140		f->fmt.pix.quantization, f->fmt.pix.xfer_func,
141		f->fmt.pix.ycbcr_enc);
142
143	vcapture->format = f->fmt.pix;
144
145	return 0;
146}
147
148static int vimc_capture_enum_fmt_vid_cap(struct file *file, void *priv,
149				     struct v4l2_fmtdesc *f)
150{
151	const struct vimc_pix_map *vpix;
152
153	if (f->mbus_code) {
154		if (f->index > 0)
155			return -EINVAL;
156
157		vpix = vimc_pix_map_by_code(f->mbus_code);
158	} else {
159		vpix = vimc_pix_map_by_index(f->index);
160	}
161
162	if (!vpix)
163		return -EINVAL;
164
165	f->pixelformat = vpix->pixelformat;
166
167	return 0;
168}
169
170static int vimc_capture_enum_framesizes(struct file *file, void *priv,
171				    struct v4l2_frmsizeenum *fsize)
172{
173	const struct vimc_pix_map *vpix;
174
175	if (fsize->index)
176		return -EINVAL;
177
178	/* Only accept code in the pix map table */
179	vpix = vimc_pix_map_by_code(fsize->pixel_format);
180	if (!vpix)
181		return -EINVAL;
182
183	fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
184	fsize->stepwise.min_width = VIMC_FRAME_MIN_WIDTH;
185	fsize->stepwise.max_width = VIMC_FRAME_MAX_WIDTH;
186	fsize->stepwise.min_height = VIMC_FRAME_MIN_HEIGHT;
187	fsize->stepwise.max_height = VIMC_FRAME_MAX_HEIGHT;
188	fsize->stepwise.step_width = 1;
189	fsize->stepwise.step_height = 1;
190
191	return 0;
192}
193
194static const struct v4l2_file_operations vimc_capture_fops = {
195	.owner		= THIS_MODULE,
196	.open		= v4l2_fh_open,
197	.release	= vb2_fop_release,
198	.read           = vb2_fop_read,
199	.poll		= vb2_fop_poll,
200	.unlocked_ioctl = video_ioctl2,
201	.mmap           = vb2_fop_mmap,
202};
203
204static const struct v4l2_ioctl_ops vimc_capture_ioctl_ops = {
205	.vidioc_querycap = vimc_capture_querycap,
206
207	.vidioc_g_fmt_vid_cap = vimc_capture_g_fmt_vid_cap,
208	.vidioc_s_fmt_vid_cap = vimc_capture_s_fmt_vid_cap,
209	.vidioc_try_fmt_vid_cap = vimc_capture_try_fmt_vid_cap,
210	.vidioc_enum_fmt_vid_cap = vimc_capture_enum_fmt_vid_cap,
211	.vidioc_enum_framesizes = vimc_capture_enum_framesizes,
212
213	.vidioc_reqbufs = vb2_ioctl_reqbufs,
214	.vidioc_create_bufs = vb2_ioctl_create_bufs,
215	.vidioc_prepare_buf = vb2_ioctl_prepare_buf,
216	.vidioc_querybuf = vb2_ioctl_querybuf,
217	.vidioc_qbuf = vb2_ioctl_qbuf,
218	.vidioc_dqbuf = vb2_ioctl_dqbuf,
219	.vidioc_expbuf = vb2_ioctl_expbuf,
220	.vidioc_streamon = vb2_ioctl_streamon,
221	.vidioc_streamoff = vb2_ioctl_streamoff,
222	.vidioc_remove_bufs = vb2_ioctl_remove_bufs,
223};
224
225static void vimc_capture_return_all_buffers(struct vimc_capture_device *vcapture,
226					enum vb2_buffer_state state)
227{
228	struct vimc_capture_buffer *vbuf, *node;
229
230	spin_lock(&vcapture->qlock);
231
232	list_for_each_entry_safe(vbuf, node, &vcapture->buf_list, list) {
233		list_del(&vbuf->list);
234		vb2_buffer_done(&vbuf->vb2.vb2_buf, state);
235	}
236
237	spin_unlock(&vcapture->qlock);
238}
239
240static int vimc_capture_start_streaming(struct vb2_queue *vq, unsigned int count)
241{
242	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
243	int ret;
244
245	vcapture->sequence = 0;
246
247	/* Start the media pipeline */
248	ret = video_device_pipeline_start(&vcapture->vdev, &vcapture->stream.pipe);
249	if (ret) {
250		vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_QUEUED);
251		return ret;
252	}
253
254	ret = vimc_streamer_s_stream(&vcapture->stream, &vcapture->ved, 1);
255	if (ret) {
256		video_device_pipeline_stop(&vcapture->vdev);
257		vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_QUEUED);
258		return ret;
259	}
260
261	return 0;
262}
263
264/*
265 * Stop the stream engine. Any remaining buffers in the stream queue are
266 * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
267 */
268static void vimc_capture_stop_streaming(struct vb2_queue *vq)
269{
270	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
271
272	vimc_streamer_s_stream(&vcapture->stream, &vcapture->ved, 0);
273
274	/* Stop the media pipeline */
275	video_device_pipeline_stop(&vcapture->vdev);
276
277	/* Release all active buffers */
278	vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_ERROR);
279}
280
281static void vimc_capture_buf_queue(struct vb2_buffer *vb2_buf)
282{
283	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vb2_buf->vb2_queue);
284	struct vimc_capture_buffer *buf = container_of(vb2_buf,
285						   struct vimc_capture_buffer,
286						   vb2.vb2_buf);
287
288	spin_lock(&vcapture->qlock);
289	list_add_tail(&buf->list, &vcapture->buf_list);
290	spin_unlock(&vcapture->qlock);
291}
292
293static int vimc_capture_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
294				unsigned int *nplanes, unsigned int sizes[],
295				struct device *alloc_devs[])
296{
297	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
298
299	if (*nplanes)
300		return sizes[0] < vcapture->format.sizeimage ? -EINVAL : 0;
301	/* We don't support multiplanes for now */
302	*nplanes = 1;
303	sizes[0] = vcapture->format.sizeimage;
304
305	return 0;
306}
307
308static int vimc_capture_buffer_prepare(struct vb2_buffer *vb)
309{
310	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vb->vb2_queue);
311	unsigned long size = vcapture->format.sizeimage;
312
313	if (vb2_plane_size(vb, 0) < size) {
314		dev_err(vcapture->ved.dev, "%s: buffer too small (%lu < %lu)\n",
315			vcapture->vdev.name, vb2_plane_size(vb, 0), size);
316		return -EINVAL;
317	}
318	return 0;
319}
320
321static const struct vb2_ops vimc_capture_qops = {
322	.start_streaming	= vimc_capture_start_streaming,
323	.stop_streaming		= vimc_capture_stop_streaming,
324	.buf_queue		= vimc_capture_buf_queue,
325	.queue_setup		= vimc_capture_queue_setup,
326	.buf_prepare		= vimc_capture_buffer_prepare,
327};
328
329static const struct media_entity_operations vimc_capture_mops = {
330	.link_validate		= vimc_vdev_link_validate,
331};
332
333static void vimc_capture_release(struct vimc_ent_device *ved)
334{
335	struct vimc_capture_device *vcapture =
336		container_of(ved, struct vimc_capture_device, ved);
337
338	media_entity_cleanup(vcapture->ved.ent);
339	kfree(vcapture);
340}
341
342static void vimc_capture_unregister(struct vimc_ent_device *ved)
343{
344	struct vimc_capture_device *vcapture =
345		container_of(ved, struct vimc_capture_device, ved);
346
347	vb2_video_unregister_device(&vcapture->vdev);
348}
349
350static void *vimc_capture_process_frame(struct vimc_ent_device *ved,
351				    const void *frame)
352{
353	struct vimc_capture_device *vcapture = container_of(ved, struct vimc_capture_device,
354						    ved);
355	struct vimc_capture_buffer *vimc_buf;
356	void *vbuf;
357
358	spin_lock(&vcapture->qlock);
359
360	/* Get the first entry of the list */
361	vimc_buf = list_first_entry_or_null(&vcapture->buf_list,
362					    typeof(*vimc_buf), list);
363	if (!vimc_buf) {
364		spin_unlock(&vcapture->qlock);
365		return ERR_PTR(-EAGAIN);
366	}
367
368	/* Remove this entry from the list */
369	list_del(&vimc_buf->list);
370
371	spin_unlock(&vcapture->qlock);
372
373	/* Fill the buffer */
374	vimc_buf->vb2.vb2_buf.timestamp = ktime_get_ns();
375	vimc_buf->vb2.sequence = vcapture->sequence++;
376	vimc_buf->vb2.field = vcapture->format.field;
377
378	vbuf = vb2_plane_vaddr(&vimc_buf->vb2.vb2_buf, 0);
379
380	memcpy(vbuf, frame, vcapture->format.sizeimage);
381
382	/* Set it as ready */
383	vb2_set_plane_payload(&vimc_buf->vb2.vb2_buf, 0,
384			      vcapture->format.sizeimage);
385	vb2_buffer_done(&vimc_buf->vb2.vb2_buf, VB2_BUF_STATE_DONE);
386	return NULL;
387}
388
389static struct vimc_ent_device *vimc_capture_add(struct vimc_device *vimc,
390					    const char *vcfg_name)
391{
392	struct v4l2_device *v4l2_dev = &vimc->v4l2_dev;
393	const struct vimc_pix_map *vpix;
394	struct vimc_capture_device *vcapture;
395	struct video_device *vdev;
396	struct vb2_queue *q;
397	int ret;
398
399	/* Allocate the vimc_capture_device struct */
400	vcapture = kzalloc(sizeof(*vcapture), GFP_KERNEL);
401	if (!vcapture)
402		return ERR_PTR(-ENOMEM);
403
404	/* Initialize the media entity */
405	vcapture->vdev.entity.name = vcfg_name;
406	vcapture->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
407	vcapture->pad.flags = MEDIA_PAD_FL_SINK;
408	ret = media_entity_pads_init(&vcapture->vdev.entity,
409				     1, &vcapture->pad);
410	if (ret)
411		goto err_free_vcapture;
412
413	/* Initialize the lock */
414	mutex_init(&vcapture->lock);
415
416	/* Initialize the vb2 queue */
417	q = &vcapture->queue;
418	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
419	q->io_modes = VB2_MMAP | VB2_DMABUF;
420	if (vimc_allocator == VIMC_ALLOCATOR_VMALLOC)
421		q->io_modes |= VB2_USERPTR;
422	q->drv_priv = vcapture;
423	q->buf_struct_size = sizeof(struct vimc_capture_buffer);
424	q->ops = &vimc_capture_qops;
425	q->mem_ops = vimc_allocator == VIMC_ALLOCATOR_DMA_CONTIG
426		   ? &vb2_dma_contig_memops : &vb2_vmalloc_memops;
427	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
428	q->min_reqbufs_allocation = 2;
429	q->lock = &vcapture->lock;
430	q->dev = v4l2_dev->dev;
431
432	ret = vb2_queue_init(q);
433	if (ret) {
434		dev_err(vimc->mdev.dev, "%s: vb2 queue init failed (err=%d)\n",
435			vcfg_name, ret);
436		goto err_clean_m_ent;
437	}
438
439	/* Initialize buffer list and its lock */
440	INIT_LIST_HEAD(&vcapture->buf_list);
441	spin_lock_init(&vcapture->qlock);
442
443	/* Set default frame format */
444	vcapture->format = fmt_default;
445	vpix = vimc_pix_map_by_pixelformat(vcapture->format.pixelformat);
446	vcapture->format.bytesperline = vcapture->format.width * vpix->bpp;
447	vcapture->format.sizeimage = vcapture->format.bytesperline *
448				 vcapture->format.height;
449
450	/* Fill the vimc_ent_device struct */
451	vcapture->ved.ent = &vcapture->vdev.entity;
452	vcapture->ved.process_frame = vimc_capture_process_frame;
453	vcapture->ved.vdev_get_format = vimc_capture_get_format;
454	vcapture->ved.dev = vimc->mdev.dev;
455
456	/* Initialize the video_device struct */
457	vdev = &vcapture->vdev;
458	vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING
459			  | V4L2_CAP_IO_MC;
460	vdev->entity.ops = &vimc_capture_mops;
461	vdev->release = video_device_release_empty;
462	vdev->fops = &vimc_capture_fops;
463	vdev->ioctl_ops = &vimc_capture_ioctl_ops;
464	vdev->lock = &vcapture->lock;
465	vdev->queue = q;
466	vdev->v4l2_dev = v4l2_dev;
467	vdev->vfl_dir = VFL_DIR_RX;
468	strscpy(vdev->name, vcfg_name, sizeof(vdev->name));
469	video_set_drvdata(vdev, &vcapture->ved);
470
471	/* Register the video_device with the v4l2 and the media framework */
472	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
473	if (ret) {
474		dev_err(vimc->mdev.dev, "%s: video register failed (err=%d)\n",
475			vcapture->vdev.name, ret);
476		goto err_clean_m_ent;
477	}
478
479	return &vcapture->ved;
480
481err_clean_m_ent:
482	media_entity_cleanup(&vcapture->vdev.entity);
483err_free_vcapture:
484	kfree(vcapture);
485
486	return ERR_PTR(ret);
487}
488
489const struct vimc_ent_type vimc_capture_type = {
490	.add = vimc_capture_add,
491	.unregister = vimc_capture_unregister,
492	.release = vimc_capture_release
493};