2 * vimc-capture.c Virtual Media Controller Driver
4 * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
18 #include <linux/component.h>
19 #include <linux/module.h>
20 #include <linux/platform_device.h>
21 #include <media/v4l2-ioctl.h>
22 #include <media/videobuf2-core.h>
23 #include <media/videobuf2-vmalloc.h>
25 #include "vimc-common.h"
26 #include "vimc-streamer.h"
28 #define VIMC_CAP_DRV_NAME "vimc-capture"
30 struct vimc_cap_device {
31 struct vimc_ent_device ved;
32 struct video_device vdev;
34 struct v4l2_pix_format format;
35 struct vb2_queue queue;
36 struct list_head buf_list;
38 * NOTE: in a real driver, a spin lock must be used to access the
39 * queue because the frames are generated from a hardware interruption
40 * and the isr is not allowed to sleep.
41 * Even if it is not necessary a spinlock in the vimc driver, we
42 * use it here as a code reference
47 struct vimc_stream stream;
50 static const struct v4l2_pix_format fmt_default = {
53 .pixelformat = V4L2_PIX_FMT_RGB24,
54 .field = V4L2_FIELD_NONE,
55 .colorspace = V4L2_COLORSPACE_DEFAULT,
58 struct vimc_cap_buffer {
60 * struct vb2_v4l2_buffer must be the first element
61 * the videobuf2 framework will allocate this struct based on
62 * buf_struct_size and use the first sizeof(struct vb2_buffer) bytes of
63 * memory as a vb2_buffer
65 struct vb2_v4l2_buffer vb2;
66 struct list_head list;
69 static int vimc_cap_querycap(struct file *file, void *priv,
70 struct v4l2_capability *cap)
72 struct vimc_cap_device *vcap = video_drvdata(file);
74 strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
75 strlcpy(cap->card, KBUILD_MODNAME, sizeof(cap->card));
76 snprintf(cap->bus_info, sizeof(cap->bus_info),
77 "platform:%s", vcap->vdev.v4l2_dev->name);
82 static void vimc_cap_get_format(struct vimc_ent_device *ved,
83 struct v4l2_pix_format *fmt)
85 struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
91 static int vimc_cap_g_fmt_vid_cap(struct file *file, void *priv,
92 struct v4l2_format *f)
94 struct vimc_cap_device *vcap = video_drvdata(file);
96 f->fmt.pix = vcap->format;
101 static int vimc_cap_try_fmt_vid_cap(struct file *file, void *priv,
102 struct v4l2_format *f)
104 struct v4l2_pix_format *format = &f->fmt.pix;
105 const struct vimc_pix_map *vpix;
107 format->width = clamp_t(u32, format->width, VIMC_FRAME_MIN_WIDTH,
108 VIMC_FRAME_MAX_WIDTH) & ~1;
109 format->height = clamp_t(u32, format->height, VIMC_FRAME_MIN_HEIGHT,
110 VIMC_FRAME_MAX_HEIGHT) & ~1;
112 /* Don't accept a pixelformat that is not on the table */
113 vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
115 format->pixelformat = fmt_default.pixelformat;
116 vpix = vimc_pix_map_by_pixelformat(format->pixelformat);
118 /* TODO: Add support for custom bytesperline values */
119 format->bytesperline = format->width * vpix->bpp;
120 format->sizeimage = format->bytesperline * format->height;
122 if (format->field == V4L2_FIELD_ANY)
123 format->field = fmt_default.field;
125 vimc_colorimetry_clamp(format);
130 static int vimc_cap_s_fmt_vid_cap(struct file *file, void *priv,
131 struct v4l2_format *f)
133 struct vimc_cap_device *vcap = video_drvdata(file);
136 /* Do not change the format while stream is on */
137 if (vb2_is_busy(&vcap->queue))
140 ret = vimc_cap_try_fmt_vid_cap(file, priv, f);
144 dev_dbg(vcap->dev, "%s: format update: "
145 "old:%dx%d (0x%x, %d, %d, %d, %d) "
146 "new:%dx%d (0x%x, %d, %d, %d, %d)\n", vcap->vdev.name,
148 vcap->format.width, vcap->format.height,
149 vcap->format.pixelformat, vcap->format.colorspace,
150 vcap->format.quantization, vcap->format.xfer_func,
151 vcap->format.ycbcr_enc,
153 f->fmt.pix.width, f->fmt.pix.height,
154 f->fmt.pix.pixelformat, f->fmt.pix.colorspace,
155 f->fmt.pix.quantization, f->fmt.pix.xfer_func,
156 f->fmt.pix.ycbcr_enc);
158 vcap->format = f->fmt.pix;
163 static int vimc_cap_enum_fmt_vid_cap(struct file *file, void *priv,
164 struct v4l2_fmtdesc *f)
166 const struct vimc_pix_map *vpix = vimc_pix_map_by_index(f->index);
171 f->pixelformat = vpix->pixelformat;
176 static int vimc_cap_enum_framesizes(struct file *file, void *fh,
177 struct v4l2_frmsizeenum *fsize)
179 const struct vimc_pix_map *vpix;
184 /* Only accept code in the pix map table */
185 vpix = vimc_pix_map_by_code(fsize->pixel_format);
189 fsize->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
190 fsize->stepwise.min_width = VIMC_FRAME_MIN_WIDTH;
191 fsize->stepwise.max_width = VIMC_FRAME_MAX_WIDTH;
192 fsize->stepwise.min_height = VIMC_FRAME_MIN_HEIGHT;
193 fsize->stepwise.max_height = VIMC_FRAME_MAX_HEIGHT;
194 fsize->stepwise.step_width = 2;
195 fsize->stepwise.step_height = 2;
200 static const struct v4l2_file_operations vimc_cap_fops = {
201 .owner = THIS_MODULE,
202 .open = v4l2_fh_open,
203 .release = vb2_fop_release,
204 .read = vb2_fop_read,
205 .poll = vb2_fop_poll,
206 .unlocked_ioctl = video_ioctl2,
207 .mmap = vb2_fop_mmap,
210 static const struct v4l2_ioctl_ops vimc_cap_ioctl_ops = {
211 .vidioc_querycap = vimc_cap_querycap,
213 .vidioc_g_fmt_vid_cap = vimc_cap_g_fmt_vid_cap,
214 .vidioc_s_fmt_vid_cap = vimc_cap_s_fmt_vid_cap,
215 .vidioc_try_fmt_vid_cap = vimc_cap_try_fmt_vid_cap,
216 .vidioc_enum_fmt_vid_cap = vimc_cap_enum_fmt_vid_cap,
217 .vidioc_enum_framesizes = vimc_cap_enum_framesizes,
219 .vidioc_reqbufs = vb2_ioctl_reqbufs,
220 .vidioc_create_bufs = vb2_ioctl_create_bufs,
221 .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
222 .vidioc_querybuf = vb2_ioctl_querybuf,
223 .vidioc_qbuf = vb2_ioctl_qbuf,
224 .vidioc_dqbuf = vb2_ioctl_dqbuf,
225 .vidioc_expbuf = vb2_ioctl_expbuf,
226 .vidioc_streamon = vb2_ioctl_streamon,
227 .vidioc_streamoff = vb2_ioctl_streamoff,
230 static void vimc_cap_return_all_buffers(struct vimc_cap_device *vcap,
231 enum vb2_buffer_state state)
233 struct vimc_cap_buffer *vbuf, *node;
235 spin_lock(&vcap->qlock);
237 list_for_each_entry_safe(vbuf, node, &vcap->buf_list, list) {
238 list_del(&vbuf->list);
239 vb2_buffer_done(&vbuf->vb2.vb2_buf, state);
242 spin_unlock(&vcap->qlock);
245 static int vimc_cap_start_streaming(struct vb2_queue *vq, unsigned int count)
247 struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
248 struct media_entity *entity = &vcap->vdev.entity;
253 /* Start the media pipeline */
254 ret = media_pipeline_start(entity, &vcap->stream.pipe);
256 vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
260 ret = vimc_streamer_s_stream(&vcap->stream, &vcap->ved, 1);
262 media_pipeline_stop(entity);
263 vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
271 * Stop the stream engine. Any remaining buffers in the stream queue are
272 * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
274 static void vimc_cap_stop_streaming(struct vb2_queue *vq)
276 struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
278 vimc_streamer_s_stream(&vcap->stream, &vcap->ved, 0);
280 /* Stop the media pipeline */
281 media_pipeline_stop(&vcap->vdev.entity);
283 /* Release all active buffers */
284 vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_ERROR);
287 static void vimc_cap_buf_queue(struct vb2_buffer *vb2_buf)
289 struct vimc_cap_device *vcap = vb2_get_drv_priv(vb2_buf->vb2_queue);
290 struct vimc_cap_buffer *buf = container_of(vb2_buf,
291 struct vimc_cap_buffer,
294 spin_lock(&vcap->qlock);
295 list_add_tail(&buf->list, &vcap->buf_list);
296 spin_unlock(&vcap->qlock);
299 static int vimc_cap_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
300 unsigned int *nplanes, unsigned int sizes[],
301 struct device *alloc_devs[])
303 struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
306 return sizes[0] < vcap->format.sizeimage ? -EINVAL : 0;
307 /* We don't support multiplanes for now */
309 sizes[0] = vcap->format.sizeimage;
314 static int vimc_cap_buffer_prepare(struct vb2_buffer *vb)
316 struct vimc_cap_device *vcap = vb2_get_drv_priv(vb->vb2_queue);
317 unsigned long size = vcap->format.sizeimage;
319 if (vb2_plane_size(vb, 0) < size) {
320 dev_err(vcap->dev, "%s: buffer too small (%lu < %lu)\n",
321 vcap->vdev.name, vb2_plane_size(vb, 0), size);
327 static const struct vb2_ops vimc_cap_qops = {
328 .start_streaming = vimc_cap_start_streaming,
329 .stop_streaming = vimc_cap_stop_streaming,
330 .buf_queue = vimc_cap_buf_queue,
331 .queue_setup = vimc_cap_queue_setup,
332 .buf_prepare = vimc_cap_buffer_prepare,
334 * Since q->lock is set we can use the standard
335 * vb2_ops_wait_prepare/finish helper functions.
337 .wait_prepare = vb2_ops_wait_prepare,
338 .wait_finish = vb2_ops_wait_finish,
341 static const struct media_entity_operations vimc_cap_mops = {
342 .link_validate = vimc_link_validate,
345 static void vimc_cap_comp_unbind(struct device *comp, struct device *master,
348 struct vimc_ent_device *ved = dev_get_drvdata(comp);
349 struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
352 vb2_queue_release(&vcap->queue);
353 media_entity_cleanup(ved->ent);
354 video_unregister_device(&vcap->vdev);
355 vimc_pads_cleanup(vcap->ved.pads);
359 static void *vimc_cap_process_frame(struct vimc_ent_device *ved,
362 struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
364 struct vimc_cap_buffer *vimc_buf;
367 spin_lock(&vcap->qlock);
369 /* Get the first entry of the list */
370 vimc_buf = list_first_entry_or_null(&vcap->buf_list,
371 typeof(*vimc_buf), list);
373 spin_unlock(&vcap->qlock);
374 return ERR_PTR(-EAGAIN);
377 /* Remove this entry from the list */
378 list_del(&vimc_buf->list);
380 spin_unlock(&vcap->qlock);
382 /* Fill the buffer */
383 vimc_buf->vb2.vb2_buf.timestamp = ktime_get_ns();
384 vimc_buf->vb2.sequence = vcap->sequence++;
385 vimc_buf->vb2.field = vcap->format.field;
387 vbuf = vb2_plane_vaddr(&vimc_buf->vb2.vb2_buf, 0);
389 memcpy(vbuf, frame, vcap->format.sizeimage);
391 /* Set it as ready */
392 vb2_set_plane_payload(&vimc_buf->vb2.vb2_buf, 0,
393 vcap->format.sizeimage);
394 vb2_buffer_done(&vimc_buf->vb2.vb2_buf, VB2_BUF_STATE_DONE);
398 static int vimc_cap_comp_bind(struct device *comp, struct device *master,
401 struct v4l2_device *v4l2_dev = master_data;
402 struct vimc_platform_data *pdata = comp->platform_data;
403 const struct vimc_pix_map *vpix;
404 struct vimc_cap_device *vcap;
405 struct video_device *vdev;
409 /* Allocate the vimc_cap_device struct */
410 vcap = kzalloc(sizeof(*vcap), GFP_KERNEL);
414 /* Allocate the pads */
416 vimc_pads_init(1, (const unsigned long[1]) {MEDIA_PAD_FL_SINK});
417 if (IS_ERR(vcap->ved.pads)) {
418 ret = PTR_ERR(vcap->ved.pads);
422 /* Initialize the media entity */
423 vcap->vdev.entity.name = pdata->entity_name;
424 vcap->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
425 ret = media_entity_pads_init(&vcap->vdev.entity,
430 /* Initialize the lock */
431 mutex_init(&vcap->lock);
433 /* Initialize the vb2 queue */
435 q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
436 q->io_modes = VB2_MMAP | VB2_DMABUF;
438 q->buf_struct_size = sizeof(struct vimc_cap_buffer);
439 q->ops = &vimc_cap_qops;
440 q->mem_ops = &vb2_vmalloc_memops;
441 q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
442 q->min_buffers_needed = 2;
443 q->lock = &vcap->lock;
445 ret = vb2_queue_init(q);
447 dev_err(comp, "%s: vb2 queue init failed (err=%d)\n",
448 pdata->entity_name, ret);
449 goto err_clean_m_ent;
452 /* Initialize buffer list and its lock */
453 INIT_LIST_HEAD(&vcap->buf_list);
454 spin_lock_init(&vcap->qlock);
456 /* Set default frame format */
457 vcap->format = fmt_default;
458 vpix = vimc_pix_map_by_pixelformat(vcap->format.pixelformat);
459 vcap->format.bytesperline = vcap->format.width * vpix->bpp;
460 vcap->format.sizeimage = vcap->format.bytesperline *
463 /* Fill the vimc_ent_device struct */
464 vcap->ved.ent = &vcap->vdev.entity;
465 vcap->ved.process_frame = vimc_cap_process_frame;
466 vcap->ved.vdev_get_format = vimc_cap_get_format;
467 dev_set_drvdata(comp, &vcap->ved);
470 /* Initialize the video_device struct */
472 vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
473 vdev->entity.ops = &vimc_cap_mops;
474 vdev->release = video_device_release_empty;
475 vdev->fops = &vimc_cap_fops;
476 vdev->ioctl_ops = &vimc_cap_ioctl_ops;
477 vdev->lock = &vcap->lock;
479 vdev->v4l2_dev = v4l2_dev;
480 vdev->vfl_dir = VFL_DIR_RX;
481 strlcpy(vdev->name, pdata->entity_name, sizeof(vdev->name));
482 video_set_drvdata(vdev, &vcap->ved);
484 /* Register the video_device with the v4l2 and the media framework */
485 ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
487 dev_err(comp, "%s: video register failed (err=%d)\n",
488 vcap->vdev.name, ret);
489 goto err_release_queue;
495 vb2_queue_release(q);
497 media_entity_cleanup(&vcap->vdev.entity);
499 vimc_pads_cleanup(vcap->ved.pads);
506 static const struct component_ops vimc_cap_comp_ops = {
507 .bind = vimc_cap_comp_bind,
508 .unbind = vimc_cap_comp_unbind,
511 static int vimc_cap_probe(struct platform_device *pdev)
513 return component_add(&pdev->dev, &vimc_cap_comp_ops);
516 static int vimc_cap_remove(struct platform_device *pdev)
518 component_del(&pdev->dev, &vimc_cap_comp_ops);
523 static const struct platform_device_id vimc_cap_driver_ids[] = {
525 .name = VIMC_CAP_DRV_NAME,
530 static struct platform_driver vimc_cap_pdrv = {
531 .probe = vimc_cap_probe,
532 .remove = vimc_cap_remove,
533 .id_table = vimc_cap_driver_ids,
535 .name = VIMC_CAP_DRV_NAME,
539 module_platform_driver(vimc_cap_pdrv);
541 MODULE_DEVICE_TABLE(platform, vimc_cap_driver_ids);
543 MODULE_DESCRIPTION("Virtual Media Controller Driver (VIMC) Capture");
544 MODULE_AUTHOR("Helen Mae Koike Fornazier <helen.fornazier@gmail.com>");
545 MODULE_LICENSE("GPL");