[PATCH 1/6] staging: Import the BCM2835 MMAL-based V4L2 camera driver.
Hans Verkuil
hverkuil at xs4all.nl
Mon Feb 6 12:59:35 UTC 2017
On 01/27/2017 10:54 PM, Eric Anholt wrote:
> - Supports raw YUV capture, preview, JPEG and H264.
> - Uses videobuf2 for data transfer, using dma_buf.
> - Uses 3.6.10 timestamping
> - Camera power based on use
> - Uses immutable input mode on video encoder
>
> This code comes from the Raspberry Pi kernel tree (rpi-4.9.y) as of
> a15ba877dab4e61ea3fc7b006e2a73828b083c52.
>
> Signed-off-by: Eric Anholt <eric at anholt.net>
> ---
> .../media/platform/bcm2835/bcm2835-camera.c | 2016 ++++++++++++++++++++
> .../media/platform/bcm2835/bcm2835-camera.h | 145 ++
> drivers/staging/media/platform/bcm2835/controls.c | 1345 +++++++++++++
> .../staging/media/platform/bcm2835/mmal-common.h | 53 +
> .../media/platform/bcm2835/mmal-encodings.h | 127 ++
> .../media/platform/bcm2835/mmal-msg-common.h | 50 +
> .../media/platform/bcm2835/mmal-msg-format.h | 81 +
> .../staging/media/platform/bcm2835/mmal-msg-port.h | 107 ++
> drivers/staging/media/platform/bcm2835/mmal-msg.h | 404 ++++
> .../media/platform/bcm2835/mmal-parameters.h | 689 +++++++
> .../staging/media/platform/bcm2835/mmal-vchiq.c | 1916 +++++++++++++++++++
> .../staging/media/platform/bcm2835/mmal-vchiq.h | 178 ++
> 12 files changed, 7111 insertions(+)
> create mode 100644 drivers/staging/media/platform/bcm2835/bcm2835-camera.c
> create mode 100644 drivers/staging/media/platform/bcm2835/bcm2835-camera.h
> create mode 100644 drivers/staging/media/platform/bcm2835/controls.c
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-common.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-encodings.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-msg-common.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-msg-format.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-msg-port.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-msg.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-parameters.h
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-vchiq.c
> create mode 100644 drivers/staging/media/platform/bcm2835/mmal-vchiq.h
>
> diff --git a/drivers/staging/media/platform/bcm2835/bcm2835-camera.c b/drivers/staging/media/platform/bcm2835/bcm2835-camera.c
> new file mode 100644
> index 000000000000..4f03949aecf3
> --- /dev/null
> +++ b/drivers/staging/media/platform/bcm2835/bcm2835-camera.c
> @@ -0,0 +1,2016 @@
<snip>
> +static int __init bm2835_mmal_init(void)
> +{
> + int ret;
> + struct bm2835_mmal_dev *dev;
> + struct vb2_queue *q;
> + int camera;
> + unsigned int num_cameras;
> + struct vchiq_mmal_instance *instance;
> + unsigned int resolutions[MAX_BCM2835_CAMERAS][2];
> +
> + ret = vchiq_mmal_init(&instance);
> + if (ret < 0)
> + return ret;
> +
> + num_cameras = get_num_cameras(instance,
> + resolutions,
> + MAX_BCM2835_CAMERAS);
> + if (num_cameras > MAX_BCM2835_CAMERAS)
> + num_cameras = MAX_BCM2835_CAMERAS;
> +
> + for (camera = 0; camera < num_cameras; camera++) {
> + dev = kzalloc(sizeof(struct bm2835_mmal_dev), GFP_KERNEL);
> + if (!dev)
> + return -ENOMEM;
> +
> + dev->camera_num = camera;
> + dev->max_width = resolutions[camera][0];
> + dev->max_height = resolutions[camera][1];
> +
> + /* setup device defaults */
> + dev->overlay.w.left = 150;
> + dev->overlay.w.top = 50;
> + dev->overlay.w.width = 1024;
> + dev->overlay.w.height = 768;
> + dev->overlay.clipcount = 0;
> + dev->overlay.field = V4L2_FIELD_NONE;
> + dev->overlay.global_alpha = 255;
> +
> + dev->capture.fmt = &formats[3]; /* JPEG */
> +
> + /* v4l device registration */
> + snprintf(dev->v4l2_dev.name, sizeof(dev->v4l2_dev.name),
> + "%s", BM2835_MMAL_MODULE_NAME);
> + ret = v4l2_device_register(NULL, &dev->v4l2_dev);
> + if (ret)
> + goto free_dev;
> +
> + /* setup v4l controls */
> + ret = bm2835_mmal_init_controls(dev, &dev->ctrl_handler);
> + if (ret < 0)
> + goto unreg_dev;
> + dev->v4l2_dev.ctrl_handler = &dev->ctrl_handler;
> +
> + /* mmal init */
> + dev->instance = instance;
> + ret = mmal_init(dev);
> + if (ret < 0)
> + goto unreg_dev;
> +
> + /* initialize queue */
> + q = &dev->capture.vb_vidq;
> + memset(q, 0, sizeof(*q));
> + q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
> + q->io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ;
I'm missing VB2_DMABUF here!
In fact, with dmabuf support I wonder if you still need overlay support.
Using dma-buf and just pass a gpu buffer to v4l2 is preferred over overlays.
Regards,
Hans
> + q->drv_priv = dev;
> + q->buf_struct_size = sizeof(struct mmal_buffer);
> + q->ops = &bm2835_mmal_video_qops;
> + q->mem_ops = &vb2_vmalloc_memops;
> + q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
> + ret = vb2_queue_init(q);
> + if (ret < 0)
> + goto unreg_dev;
> +
> + /* v4l2 core mutex used to protect all fops and v4l2 ioctls. */
> + mutex_init(&dev->mutex);
> +
> + /* initialise video devices */
> + ret = bm2835_mmal_init_device(dev, &dev->vdev);
> + if (ret < 0)
> + goto unreg_dev;
> +
> + /* Really want to call vidioc_s_fmt_vid_cap with the default
> + * format, but currently the APIs don't join up.
> + */
> + ret = mmal_setup_components(dev, &default_v4l2_format);
> + if (ret < 0) {
> + v4l2_err(&dev->v4l2_dev,
> + "%s: could not setup components\n", __func__);
> + goto unreg_dev;
> + }
> +
> + v4l2_info(&dev->v4l2_dev,
> + "Broadcom 2835 MMAL video capture ver %s loaded.\n",
> + BM2835_MMAL_VERSION);
> +
> + gdev[camera] = dev;
> + }
> + return 0;
> +
> +unreg_dev:
> + v4l2_ctrl_handler_free(&dev->ctrl_handler);
> + v4l2_device_unregister(&dev->v4l2_dev);
> +
> +free_dev:
> + kfree(dev);
> +
> + for ( ; camera > 0; camera--) {
> + bcm2835_cleanup_instance(gdev[camera]);
> + gdev[camera] = NULL;
> + }
> + pr_info("%s: error %d while loading driver\n",
> + BM2835_MMAL_MODULE_NAME, ret);
> +
> + return ret;
> +}
> +
> +static void __exit bm2835_mmal_exit(void)
> +{
> + int camera;
> + struct vchiq_mmal_instance *instance = gdev[0]->instance;
> +
> + for (camera = 0; camera < MAX_BCM2835_CAMERAS; camera++) {
> + bcm2835_cleanup_instance(gdev[camera]);
> + gdev[camera] = NULL;
> + }
> + vchiq_mmal_finalise(instance);
> +}
> +
> +module_init(bm2835_mmal_init);
> +module_exit(bm2835_mmal_exit);
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