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 
16 struct 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 
36 static 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 
44 struct 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 
55 static 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 	snprintf(cap->bus_info, sizeof(cap->bus_info),
61 		 "platform:%s", VIMC_PDEV_NAME);
62 
63 	return 0;
64 }
65 
66 static void vimc_capture_get_format(struct vimc_ent_device *ved,
67 				struct v4l2_pix_format *fmt)
68 {
69 	struct vimc_capture_device *vcapture = container_of(ved, struct vimc_capture_device,
70 						    ved);
71 
72 	*fmt = vcapture->format;
73 }
74 
75 static int vimc_capture_g_fmt_vid_cap(struct file *file, void *priv,
76 				  struct v4l2_format *f)
77 {
78 	struct vimc_capture_device *vcapture = video_drvdata(file);
79 
80 	f->fmt.pix = vcapture->format;
81 
82 	return 0;
83 }
84 
85 static int vimc_capture_try_fmt_vid_cap(struct file *file, void *priv,
86 				    struct v4l2_format *f)
87 {
88 	struct v4l2_pix_format *format = &f->fmt.pix;
89 	const struct vimc_pix_map *vpix;
90 
91 	format->width = clamp_t(u32, format->width, VIMC_FRAME_MIN_WIDTH,
92 				VIMC_FRAME_MAX_WIDTH) & ~1;
93 	format->height = clamp_t(u32, format->height, VIMC_FRAME_MIN_HEIGHT,
94 				 VIMC_FRAME_MAX_HEIGHT) & ~1;
95 
96 	/* Don't accept a pixelformat that is not on the table */
97 	vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
98 	if (!vpix) {
99 		format->pixelformat = fmt_default.pixelformat;
100 		vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
101 	}
102 	/* TODO: Add support for custom bytesperline values */
103 	format->bytesperline = format->width * vpix->bpp;
104 	format->sizeimage = format->bytesperline * format->height;
105 
106 	if (format->field == V4L2_FIELD_ANY)
107 		format->field = fmt_default.field;
108 
109 	vimc_colorimetry_clamp(format);
110 
111 	if (format->colorspace == V4L2_COLORSPACE_DEFAULT)
112 		format->colorspace = fmt_default.colorspace;
113 
114 	return 0;
115 }
116 
117 static int vimc_capture_s_fmt_vid_cap(struct file *file, void *priv,
118 				  struct v4l2_format *f)
119 {
120 	struct vimc_capture_device *vcapture = video_drvdata(file);
121 	int ret;
122 
123 	/* Do not change the format while stream is on */
124 	if (vb2_is_busy(&vcapture->queue))
125 		return -EBUSY;
126 
127 	ret = vimc_capture_try_fmt_vid_cap(file, priv, f);
128 	if (ret)
129 		return ret;
130 
131 	dev_dbg(vcapture->ved.dev, "%s: format update: "
132 		"old:%dx%d (0x%x, %d, %d, %d, %d) "
133 		"new:%dx%d (0x%x, %d, %d, %d, %d)\n", vcapture->vdev.name,
134 		/* old */
135 		vcapture->format.width, vcapture->format.height,
136 		vcapture->format.pixelformat, vcapture->format.colorspace,
137 		vcapture->format.quantization, vcapture->format.xfer_func,
138 		vcapture->format.ycbcr_enc,
139 		/* new */
140 		f->fmt.pix.width, f->fmt.pix.height,
141 		f->fmt.pix.pixelformat,	f->fmt.pix.colorspace,
142 		f->fmt.pix.quantization, f->fmt.pix.xfer_func,
143 		f->fmt.pix.ycbcr_enc);
144 
145 	vcapture->format = f->fmt.pix;
146 
147 	return 0;
148 }
149 
150 static int vimc_capture_enum_fmt_vid_cap(struct file *file, void *priv,
151 				     struct v4l2_fmtdesc *f)
152 {
153 	const struct vimc_pix_map *vpix;
154 
155 	if (f->mbus_code) {
156 		if (f->index > 0)
157 			return -EINVAL;
158 
159 		vpix = vimc_pix_map_by_code(f->mbus_code);
160 	} else {
161 		vpix = vimc_pix_map_by_index(f->index);
162 	}
163 
164 	if (!vpix)
165 		return -EINVAL;
166 
167 	f->pixelformat = vpix->pixelformat;
168 
169 	return 0;
170 }
171 
172 static int vimc_capture_enum_framesizes(struct file *file, void *fh,
173 				    struct v4l2_frmsizeenum *fsize)
174 {
175 	const struct vimc_pix_map *vpix;
176 
177 	if (fsize->index)
178 		return -EINVAL;
179 
180 	/* Only accept code in the pix map table */
181 	vpix = vimc_pix_map_by_code(fsize->pixel_format);
182 	if (!vpix)
183 		return -EINVAL;
184 
185 	fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
186 	fsize->stepwise.min_width = VIMC_FRAME_MIN_WIDTH;
187 	fsize->stepwise.max_width = VIMC_FRAME_MAX_WIDTH;
188 	fsize->stepwise.min_height = VIMC_FRAME_MIN_HEIGHT;
189 	fsize->stepwise.max_height = VIMC_FRAME_MAX_HEIGHT;
190 	fsize->stepwise.step_width = 1;
191 	fsize->stepwise.step_height = 1;
192 
193 	return 0;
194 }
195 
196 static const struct v4l2_file_operations vimc_capture_fops = {
197 	.owner		= THIS_MODULE,
198 	.open		= v4l2_fh_open,
199 	.release	= vb2_fop_release,
200 	.read           = vb2_fop_read,
201 	.poll		= vb2_fop_poll,
202 	.unlocked_ioctl = video_ioctl2,
203 	.mmap           = vb2_fop_mmap,
204 };
205 
206 static const struct v4l2_ioctl_ops vimc_capture_ioctl_ops = {
207 	.vidioc_querycap = vimc_capture_querycap,
208 
209 	.vidioc_g_fmt_vid_cap = vimc_capture_g_fmt_vid_cap,
210 	.vidioc_s_fmt_vid_cap = vimc_capture_s_fmt_vid_cap,
211 	.vidioc_try_fmt_vid_cap = vimc_capture_try_fmt_vid_cap,
212 	.vidioc_enum_fmt_vid_cap = vimc_capture_enum_fmt_vid_cap,
213 	.vidioc_enum_framesizes = vimc_capture_enum_framesizes,
214 
215 	.vidioc_reqbufs = vb2_ioctl_reqbufs,
216 	.vidioc_create_bufs = vb2_ioctl_create_bufs,
217 	.vidioc_prepare_buf = vb2_ioctl_prepare_buf,
218 	.vidioc_querybuf = vb2_ioctl_querybuf,
219 	.vidioc_qbuf = vb2_ioctl_qbuf,
220 	.vidioc_dqbuf = vb2_ioctl_dqbuf,
221 	.vidioc_expbuf = vb2_ioctl_expbuf,
222 	.vidioc_streamon = vb2_ioctl_streamon,
223 	.vidioc_streamoff = vb2_ioctl_streamoff,
224 };
225 
226 static void vimc_capture_return_all_buffers(struct vimc_capture_device *vcapture,
227 					enum vb2_buffer_state state)
228 {
229 	struct vimc_capture_buffer *vbuf, *node;
230 
231 	spin_lock(&vcapture->qlock);
232 
233 	list_for_each_entry_safe(vbuf, node, &vcapture->buf_list, list) {
234 		list_del(&vbuf->list);
235 		vb2_buffer_done(&vbuf->vb2.vb2_buf, state);
236 	}
237 
238 	spin_unlock(&vcapture->qlock);
239 }
240 
241 static int vimc_capture_start_streaming(struct vb2_queue *vq, unsigned int count)
242 {
243 	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
244 	int ret;
245 
246 	vcapture->sequence = 0;
247 
248 	/* Start the media pipeline */
249 	ret = video_device_pipeline_start(&vcapture->vdev, &vcapture->stream.pipe);
250 	if (ret) {
251 		vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_QUEUED);
252 		return ret;
253 	}
254 
255 	ret = vimc_streamer_s_stream(&vcapture->stream, &vcapture->ved, 1);
256 	if (ret) {
257 		video_device_pipeline_stop(&vcapture->vdev);
258 		vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_QUEUED);
259 		return ret;
260 	}
261 
262 	return 0;
263 }
264 
265 /*
266  * Stop the stream engine. Any remaining buffers in the stream queue are
267  * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
268  */
269 static void vimc_capture_stop_streaming(struct vb2_queue *vq)
270 {
271 	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
272 
273 	vimc_streamer_s_stream(&vcapture->stream, &vcapture->ved, 0);
274 
275 	/* Stop the media pipeline */
276 	video_device_pipeline_stop(&vcapture->vdev);
277 
278 	/* Release all active buffers */
279 	vimc_capture_return_all_buffers(vcapture, VB2_BUF_STATE_ERROR);
280 }
281 
282 static void vimc_capture_buf_queue(struct vb2_buffer *vb2_buf)
283 {
284 	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vb2_buf->vb2_queue);
285 	struct vimc_capture_buffer *buf = container_of(vb2_buf,
286 						   struct vimc_capture_buffer,
287 						   vb2.vb2_buf);
288 
289 	spin_lock(&vcapture->qlock);
290 	list_add_tail(&buf->list, &vcapture->buf_list);
291 	spin_unlock(&vcapture->qlock);
292 }
293 
294 static int vimc_capture_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
295 				unsigned int *nplanes, unsigned int sizes[],
296 				struct device *alloc_devs[])
297 {
298 	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vq);
299 
300 	if (*nplanes)
301 		return sizes[0] < vcapture->format.sizeimage ? -EINVAL : 0;
302 	/* We don't support multiplanes for now */
303 	*nplanes = 1;
304 	sizes[0] = vcapture->format.sizeimage;
305 
306 	return 0;
307 }
308 
309 static int vimc_capture_buffer_prepare(struct vb2_buffer *vb)
310 {
311 	struct vimc_capture_device *vcapture = vb2_get_drv_priv(vb->vb2_queue);
312 	unsigned long size = vcapture->format.sizeimage;
313 
314 	if (vb2_plane_size(vb, 0) < size) {
315 		dev_err(vcapture->ved.dev, "%s: buffer too small (%lu < %lu)\n",
316 			vcapture->vdev.name, vb2_plane_size(vb, 0), size);
317 		return -EINVAL;
318 	}
319 	return 0;
320 }
321 
322 static const struct vb2_ops vimc_capture_qops = {
323 	.start_streaming	= vimc_capture_start_streaming,
324 	.stop_streaming		= vimc_capture_stop_streaming,
325 	.buf_queue		= vimc_capture_buf_queue,
326 	.queue_setup		= vimc_capture_queue_setup,
327 	.buf_prepare		= vimc_capture_buffer_prepare,
328 	/*
329 	 * Since q->lock is set we can use the standard
330 	 * vb2_ops_wait_prepare/finish helper functions.
331 	 */
332 	.wait_prepare		= vb2_ops_wait_prepare,
333 	.wait_finish		= vb2_ops_wait_finish,
334 };
335 
336 static const struct media_entity_operations vimc_capture_mops = {
337 	.link_validate		= vimc_vdev_link_validate,
338 };
339 
340 static void vimc_capture_release(struct vimc_ent_device *ved)
341 {
342 	struct vimc_capture_device *vcapture =
343 		container_of(ved, struct vimc_capture_device, ved);
344 
345 	media_entity_cleanup(vcapture->ved.ent);
346 	kfree(vcapture);
347 }
348 
349 static void vimc_capture_unregister(struct vimc_ent_device *ved)
350 {
351 	struct vimc_capture_device *vcapture =
352 		container_of(ved, struct vimc_capture_device, ved);
353 
354 	vb2_video_unregister_device(&vcapture->vdev);
355 }
356 
357 static void *vimc_capture_process_frame(struct vimc_ent_device *ved,
358 				    const void *frame)
359 {
360 	struct vimc_capture_device *vcapture = container_of(ved, struct vimc_capture_device,
361 						    ved);
362 	struct vimc_capture_buffer *vimc_buf;
363 	void *vbuf;
364 
365 	spin_lock(&vcapture->qlock);
366 
367 	/* Get the first entry of the list */
368 	vimc_buf = list_first_entry_or_null(&vcapture->buf_list,
369 					    typeof(*vimc_buf), list);
370 	if (!vimc_buf) {
371 		spin_unlock(&vcapture->qlock);
372 		return ERR_PTR(-EAGAIN);
373 	}
374 
375 	/* Remove this entry from the list */
376 	list_del(&vimc_buf->list);
377 
378 	spin_unlock(&vcapture->qlock);
379 
380 	/* Fill the buffer */
381 	vimc_buf->vb2.vb2_buf.timestamp = ktime_get_ns();
382 	vimc_buf->vb2.sequence = vcapture->sequence++;
383 	vimc_buf->vb2.field = vcapture->format.field;
384 
385 	vbuf = vb2_plane_vaddr(&vimc_buf->vb2.vb2_buf, 0);
386 
387 	memcpy(vbuf, frame, vcapture->format.sizeimage);
388 
389 	/* Set it as ready */
390 	vb2_set_plane_payload(&vimc_buf->vb2.vb2_buf, 0,
391 			      vcapture->format.sizeimage);
392 	vb2_buffer_done(&vimc_buf->vb2.vb2_buf, VB2_BUF_STATE_DONE);
393 	return NULL;
394 }
395 
396 static struct vimc_ent_device *vimc_capture_add(struct vimc_device *vimc,
397 					    const char *vcfg_name)
398 {
399 	struct v4l2_device *v4l2_dev = &vimc->v4l2_dev;
400 	const struct vimc_pix_map *vpix;
401 	struct vimc_capture_device *vcapture;
402 	struct video_device *vdev;
403 	struct vb2_queue *q;
404 	int ret;
405 
406 	/* Allocate the vimc_capture_device struct */
407 	vcapture = kzalloc(sizeof(*vcapture), GFP_KERNEL);
408 	if (!vcapture)
409 		return ERR_PTR(-ENOMEM);
410 
411 	/* Initialize the media entity */
412 	vcapture->vdev.entity.name = vcfg_name;
413 	vcapture->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
414 	vcapture->pad.flags = MEDIA_PAD_FL_SINK;
415 	ret = media_entity_pads_init(&vcapture->vdev.entity,
416 				     1, &vcapture->pad);
417 	if (ret)
418 		goto err_free_vcapture;
419 
420 	/* Initialize the lock */
421 	mutex_init(&vcapture->lock);
422 
423 	/* Initialize the vb2 queue */
424 	q = &vcapture->queue;
425 	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
426 	q->io_modes = VB2_MMAP | VB2_DMABUF;
427 	if (vimc_allocator == VIMC_ALLOCATOR_VMALLOC)
428 		q->io_modes |= VB2_USERPTR;
429 	q->drv_priv = vcapture;
430 	q->buf_struct_size = sizeof(struct vimc_capture_buffer);
431 	q->ops = &vimc_capture_qops;
432 	q->mem_ops = vimc_allocator == VIMC_ALLOCATOR_DMA_CONTIG
433 		   ? &vb2_dma_contig_memops : &vb2_vmalloc_memops;
434 	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
435 	q->min_buffers_needed = 2;
436 	q->lock = &vcapture->lock;
437 	q->dev = v4l2_dev->dev;
438 
439 	ret = vb2_queue_init(q);
440 	if (ret) {
441 		dev_err(vimc->mdev.dev, "%s: vb2 queue init failed (err=%d)\n",
442 			vcfg_name, ret);
443 		goto err_clean_m_ent;
444 	}
445 
446 	/* Initialize buffer list and its lock */
447 	INIT_LIST_HEAD(&vcapture->buf_list);
448 	spin_lock_init(&vcapture->qlock);
449 
450 	/* Set default frame format */
451 	vcapture->format = fmt_default;
452 	vpix = vimc_pix_map_by_pixelformat(vcapture->format.pixelformat);
453 	vcapture->format.bytesperline = vcapture->format.width * vpix->bpp;
454 	vcapture->format.sizeimage = vcapture->format.bytesperline *
455 				 vcapture->format.height;
456 
457 	/* Fill the vimc_ent_device struct */
458 	vcapture->ved.ent = &vcapture->vdev.entity;
459 	vcapture->ved.process_frame = vimc_capture_process_frame;
460 	vcapture->ved.vdev_get_format = vimc_capture_get_format;
461 	vcapture->ved.dev = vimc->mdev.dev;
462 
463 	/* Initialize the video_device struct */
464 	vdev = &vcapture->vdev;
465 	vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING
466 			  | V4L2_CAP_IO_MC;
467 	vdev->entity.ops = &vimc_capture_mops;
468 	vdev->release = video_device_release_empty;
469 	vdev->fops = &vimc_capture_fops;
470 	vdev->ioctl_ops = &vimc_capture_ioctl_ops;
471 	vdev->lock = &vcapture->lock;
472 	vdev->queue = q;
473 	vdev->v4l2_dev = v4l2_dev;
474 	vdev->vfl_dir = VFL_DIR_RX;
475 	strscpy(vdev->name, vcfg_name, sizeof(vdev->name));
476 	video_set_drvdata(vdev, &vcapture->ved);
477 
478 	/* Register the video_device with the v4l2 and the media framework */
479 	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
480 	if (ret) {
481 		dev_err(vimc->mdev.dev, "%s: video register failed (err=%d)\n",
482 			vcapture->vdev.name, ret);
483 		goto err_clean_m_ent;
484 	}
485 
486 	return &vcapture->ved;
487 
488 err_clean_m_ent:
489 	media_entity_cleanup(&vcapture->vdev.entity);
490 err_free_vcapture:
491 	kfree(vcapture);
492 
493 	return ERR_PTR(ret);
494 }
495 
496 struct vimc_ent_type vimc_capture_type = {
497 	.add = vimc_capture_add,
498 	.unregister = vimc_capture_unregister,
499 	.release = vimc_capture_release
500 };
501