1 files changed, 498 insertions, 0 deletions

diff --git a/drivers/media/platform/vimc/vimc-capture.c b/drivers/media/platform/vimc/vimc-capture.c
new file mode 100644
index 0000000..9adb06d
--- /dev/null
+++ b/drivers/media/platform/vimc/vimc-capture.c
@@ -0,0 +1,498 @@
+/*
+ * vimc-capture.c Virtual Media Controller Driver
+ *
+ * Copyright (C) 2015-2017 Helen Koike <helen.fornazier@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-vmalloc.h>
+
+#include "vimc-capture.h"
+
+struct vimc_cap_device {
+	struct vimc_ent_device ved;
+	struct video_device vdev;
+	struct v4l2_pix_format format;
+	struct vb2_queue queue;
+	struct list_head buf_list;
+	/*
+	 * NOTE: in a real driver, a spin lock must be used to access the
+	 * queue because the frames are generated from a hardware interruption
+	 * and the isr is not allowed to sleep.
+	 * Even if it is not necessary a spinlock in the vimc driver, we
+	 * use it here as a code reference
+	 */
+	spinlock_t qlock;
+	struct mutex lock;
+	u32 sequence;
+	struct media_pipeline pipe;
+};
+
+struct vimc_cap_buffer {
+	/*
+	 * struct vb2_v4l2_buffer must be the first element
+	 * the videobuf2 framework will allocate this struct based on
+	 * buf_struct_size and use the first sizeof(struct vb2_buffer) bytes of
+	 * memory as a vb2_buffer
+	 */
+	struct vb2_v4l2_buffer vb2;
+	struct list_head list;
+};
+
+static int vimc_cap_querycap(struct file *file, void *priv,
+			     struct v4l2_capability *cap)
+{
+	struct vimc_cap_device *vcap = video_drvdata(file);
+
+	strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
+	strlcpy(cap->card, KBUILD_MODNAME, sizeof(cap->card));
+	snprintf(cap->bus_info, sizeof(cap->bus_info),
+		 "platform:%s", vcap->vdev.v4l2_dev->name);
+
+	return 0;
+}
+
+static int vimc_cap_fmt_vid_cap(struct file *file, void *priv,
+				  struct v4l2_format *f)
+{
+	struct vimc_cap_device *vcap = video_drvdata(file);
+
+	f->fmt.pix = vcap->format;
+
+	return 0;
+}
+
+static int vimc_cap_enum_fmt_vid_cap(struct file *file, void *priv,
+				     struct v4l2_fmtdesc *f)
+{
+	struct vimc_cap_device *vcap = video_drvdata(file);
+
+	if (f->index > 0)
+		return -EINVAL;
+
+	/* We only support one format for now */
+	f->pixelformat = vcap->format.pixelformat;
+
+	return 0;
+}
+
+static const struct v4l2_file_operations vimc_cap_fops = {
+	.owner		= THIS_MODULE,
+	.open		= v4l2_fh_open,
+	.release	= vb2_fop_release,
+	.read           = vb2_fop_read,
+	.poll		= vb2_fop_poll,
+	.unlocked_ioctl = video_ioctl2,
+	.mmap           = vb2_fop_mmap,
+};
+
+static const struct v4l2_ioctl_ops vimc_cap_ioctl_ops = {
+	.vidioc_querycap = vimc_cap_querycap,
+
+	.vidioc_g_fmt_vid_cap = vimc_cap_fmt_vid_cap,
+	.vidioc_s_fmt_vid_cap = vimc_cap_fmt_vid_cap,
+	.vidioc_try_fmt_vid_cap = vimc_cap_fmt_vid_cap,
+	.vidioc_enum_fmt_vid_cap = vimc_cap_enum_fmt_vid_cap,
+
+	.vidioc_reqbufs = vb2_ioctl_reqbufs,
+	.vidioc_create_bufs = vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+	.vidioc_querybuf = vb2_ioctl_querybuf,
+	.vidioc_qbuf = vb2_ioctl_qbuf,
+	.vidioc_dqbuf = vb2_ioctl_dqbuf,
+	.vidioc_expbuf = vb2_ioctl_expbuf,
+	.vidioc_streamon = vb2_ioctl_streamon,
+	.vidioc_streamoff = vb2_ioctl_streamoff,
+};
+
+static void vimc_cap_return_all_buffers(struct vimc_cap_device *vcap,
+					enum vb2_buffer_state state)
+{
+	struct vimc_cap_buffer *vbuf, *node;
+
+	spin_lock(&vcap->qlock);
+
+	list_for_each_entry_safe(vbuf, node, &vcap->buf_list, list) {
+		list_del(&vbuf->list);
+		vb2_buffer_done(&vbuf->vb2.vb2_buf, state);
+	}
+
+	spin_unlock(&vcap->qlock);
+}
+
+static int vimc_cap_pipeline_s_stream(struct vimc_cap_device *vcap, int enable)
+{
+	struct v4l2_subdev *sd;
+	struct media_pad *pad;
+	int ret;
+
+	/* Start the stream in the subdevice direct connected */
+	pad = media_entity_remote_pad(&vcap->vdev.entity.pads[0]);
+
+	/*
+	 * if it is a raw node from vimc-core, there is nothing to activate
+	 * TODO: remove this when there are no more raw nodes in the
+	 * core and return error instead
+	 */
+	if (pad->entity->obj_type == MEDIA_ENTITY_TYPE_BASE)
+		return 0;
+
+	sd = media_entity_to_v4l2_subdev(pad->entity);
+	ret = v4l2_subdev_call(sd, video, s_stream, enable);
+	if (ret && ret != -ENOIOCTLCMD)
+		return ret;
+
+	return 0;
+}
+
+static int vimc_cap_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
+	struct media_entity *entity = &vcap->vdev.entity;
+	int ret;
+
+	vcap->sequence = 0;
+
+	/* Start the media pipeline */
+	ret = media_pipeline_start(entity, &vcap->pipe);
+	if (ret) {
+		vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
+		return ret;
+	}
+
+	/* Enable streaming from the pipe */
+	ret = vimc_cap_pipeline_s_stream(vcap, 1);
+	if (ret) {
+		media_pipeline_stop(entity);
+		vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_QUEUED);
+		return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * Stop the stream engine. Any remaining buffers in the stream queue are
+ * dequeued and passed on to the vb2 framework marked as STATE_ERROR.
+ */
+static void vimc_cap_stop_streaming(struct vb2_queue *vq)
+{
+	struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
+
+	/* Disable streaming from the pipe */
+	vimc_cap_pipeline_s_stream(vcap, 0);
+
+	/* Stop the media pipeline */
+	media_pipeline_stop(&vcap->vdev.entity);
+
+	/* Release all active buffers */
+	vimc_cap_return_all_buffers(vcap, VB2_BUF_STATE_ERROR);
+}
+
+static void vimc_cap_buf_queue(struct vb2_buffer *vb2_buf)
+{
+	struct vimc_cap_device *vcap = vb2_get_drv_priv(vb2_buf->vb2_queue);
+	struct vimc_cap_buffer *buf = container_of(vb2_buf,
+						   struct vimc_cap_buffer,
+						   vb2.vb2_buf);
+
+	spin_lock(&vcap->qlock);
+	list_add_tail(&buf->list, &vcap->buf_list);
+	spin_unlock(&vcap->qlock);
+}
+
+static int vimc_cap_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
+				unsigned int *nplanes, unsigned int sizes[],
+				struct device *alloc_devs[])
+{
+	struct vimc_cap_device *vcap = vb2_get_drv_priv(vq);
+
+	if (*nplanes)
+		return sizes[0] < vcap->format.sizeimage ? -EINVAL : 0;
+	/* We don't support multiplanes for now */
+	*nplanes = 1;
+	sizes[0] = vcap->format.sizeimage;
+
+	return 0;
+}
+
+static int vimc_cap_buffer_prepare(struct vb2_buffer *vb)
+{
+	struct vimc_cap_device *vcap = vb2_get_drv_priv(vb->vb2_queue);
+	unsigned long size = vcap->format.sizeimage;
+
+	if (vb2_plane_size(vb, 0) < size) {
+		dev_err(vcap->vdev.v4l2_dev->dev,
+			"%s: buffer too small (%lu < %lu)\n",
+			vcap->vdev.name, vb2_plane_size(vb, 0), size);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static const struct vb2_ops vimc_cap_qops = {
+	.start_streaming	= vimc_cap_start_streaming,
+	.stop_streaming		= vimc_cap_stop_streaming,
+	.buf_queue		= vimc_cap_buf_queue,
+	.queue_setup		= vimc_cap_queue_setup,
+	.buf_prepare		= vimc_cap_buffer_prepare,
+	/*
+	 * Since q->lock is set we can use the standard
+	 * vb2_ops_wait_prepare/finish helper functions.
+	 */
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+/*
+ * NOTE: this function is a copy of v4l2_subdev_link_validate_get_format
+ * maybe the v4l2 function should be public
+ */
+static int vimc_cap_v4l2_subdev_link_validate_get_format(struct media_pad *pad,
+						struct v4l2_subdev_format *fmt)
+{
+	struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(pad->entity);
+
+	fmt->which = V4L2_SUBDEV_FORMAT_ACTIVE;
+	fmt->pad = pad->index;
+
+	return v4l2_subdev_call(sd, pad, get_fmt, NULL, fmt);
+}
+
+static int vimc_cap_link_validate(struct media_link *link)
+{
+	struct v4l2_subdev_format source_fmt;
+	const struct vimc_pix_map *vpix;
+	struct vimc_cap_device *vcap = container_of(link->sink->entity,
+						    struct vimc_cap_device,
+						    vdev.entity);
+	struct v4l2_pix_format *sink_fmt = &vcap->format;
+	int ret;
+
+	/*
+	 * if it is a raw node from vimc-core, ignore the link for now
+	 * TODO: remove this when there are no more raw nodes in the
+	 * core and return error instead
+	 */
+	if (link->source->entity->obj_type == MEDIA_ENTITY_TYPE_BASE)
+		return 0;
+
+	/* Get the the format of the subdev */
+	ret = vimc_cap_v4l2_subdev_link_validate_get_format(link->source,
+							    &source_fmt);
+	if (ret)
+		return ret;
+
+	dev_dbg(vcap->vdev.v4l2_dev->dev,
+		"%s: link validate formats src:%dx%d %d sink:%dx%d %d\n",
+		vcap->vdev.name,
+		source_fmt.format.width, source_fmt.format.height,
+		source_fmt.format.code,
+		sink_fmt->width, sink_fmt->height,
+		sink_fmt->pixelformat);
+
+	/* The width, height and code must match. */
+	vpix = vimc_pix_map_by_pixelformat(sink_fmt->pixelformat);
+	if (source_fmt.format.width != sink_fmt->width
+	    || source_fmt.format.height != sink_fmt->height
+	    || vpix->code != source_fmt.format.code)
+		return -EPIPE;
+
+	/*
+	 * The field order must match, or the sink field order must be NONE
+	 * to support interlaced hardware connected to bridges that support
+	 * progressive formats only.
+	 */
+	if (source_fmt.format.field != sink_fmt->field &&
+	    sink_fmt->field != V4L2_FIELD_NONE)
+		return -EPIPE;
+
+	return 0;
+}
+
+static const struct media_entity_operations vimc_cap_mops = {
+	.link_validate		= vimc_cap_link_validate,
+};
+
+static void vimc_cap_destroy(struct vimc_ent_device *ved)
+{
+	struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
+						    ved);
+
+	vb2_queue_release(&vcap->queue);
+	media_entity_cleanup(ved->ent);
+	video_unregister_device(&vcap->vdev);
+	vimc_pads_cleanup(vcap->ved.pads);
+	kfree(vcap);
+}
+
+static void vimc_cap_process_frame(struct vimc_ent_device *ved,
+				   struct media_pad *sink, const void *frame)
+{
+	struct vimc_cap_device *vcap = container_of(ved, struct vimc_cap_device,
+						    ved);
+	struct vimc_cap_buffer *vimc_buf;
+	void *vbuf;
+
+	spin_lock(&vcap->qlock);
+
+	/* Get the first entry of the list */
+	vimc_buf = list_first_entry_or_null(&vcap->buf_list,
+					    typeof(*vimc_buf), list);
+	if (!vimc_buf) {
+		spin_unlock(&vcap->qlock);
+		return;
+	}
+
+	/* Remove this entry from the list */
+	list_del(&vimc_buf->list);
+
+	spin_unlock(&vcap->qlock);
+
+	/* Fill the buffer */
+	vimc_buf->vb2.vb2_buf.timestamp = ktime_get_ns();
+	vimc_buf->vb2.sequence = vcap->sequence++;
+	vimc_buf->vb2.field = vcap->format.field;
+
+	vbuf = vb2_plane_vaddr(&vimc_buf->vb2.vb2_buf, 0);
+
+	memcpy(vbuf, frame, vcap->format.sizeimage);
+
+	/* Set it as ready */
+	vb2_set_plane_payload(&vimc_buf->vb2.vb2_buf, 0,
+			      vcap->format.sizeimage);
+	vb2_buffer_done(&vimc_buf->vb2.vb2_buf, VB2_BUF_STATE_DONE);
+}
+
+struct vimc_ent_device *vimc_cap_create(struct v4l2_device *v4l2_dev,
+					const char *const name,
+					u16 num_pads,
+					const unsigned long *pads_flag)
+{
+	const struct vimc_pix_map *vpix;
+	struct vimc_cap_device *vcap;
+	struct video_device *vdev;
+	struct vb2_queue *q;
+	int ret;
+
+	/*
+	 * Check entity configuration params
+	 * NOTE: we only support a single sink pad
+	 */
+	if (!name || num_pads != 1 || !pads_flag ||
+	    !(pads_flag[0] & MEDIA_PAD_FL_SINK))
+		return ERR_PTR(-EINVAL);
+
+	/* Allocate the vimc_cap_device struct */
+	vcap = kzalloc(sizeof(*vcap), GFP_KERNEL);
+	if (!vcap)
+		return ERR_PTR(-ENOMEM);
+
+	/* Allocate the pads */
+	vcap->ved.pads = vimc_pads_init(num_pads, pads_flag);
+	if (IS_ERR(vcap->ved.pads)) {
+		ret = PTR_ERR(vcap->ved.pads);
+		goto err_free_vcap;
+	}
+
+	/* Initialize the media entity */
+	vcap->vdev.entity.name = name;
+	vcap->vdev.entity.function = MEDIA_ENT_F_IO_V4L;
+	ret = media_entity_pads_init(&vcap->vdev.entity,
+				     num_pads, vcap->ved.pads);
+	if (ret)
+		goto err_clean_pads;
+
+	/* Initialize the lock */
+	mutex_init(&vcap->lock);
+
+	/* Initialize the vb2 queue */
+	q = &vcap->queue;
+	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	q->io_modes = VB2_MMAP | VB2_DMABUF;
+	q->drv_priv = vcap;
+	q->buf_struct_size = sizeof(struct vimc_cap_buffer);
+	q->ops = &vimc_cap_qops;
+	q->mem_ops = &vb2_vmalloc_memops;
+	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+	q->min_buffers_needed = 2;
+	q->lock = &vcap->lock;
+
+	ret = vb2_queue_init(q);
+	if (ret) {
+		dev_err(vcap->vdev.v4l2_dev->dev,
+			"%s: vb2 queue init failed (err=%d)\n",
+			vcap->vdev.name, ret);
+		goto err_clean_m_ent;
+	}
+
+	/* Initialize buffer list and its lock */
+	INIT_LIST_HEAD(&vcap->buf_list);
+	spin_lock_init(&vcap->qlock);
+
+	/* Set the frame format (this is hardcoded for now) */
+	vcap->format.width = 640;
+	vcap->format.height = 480;
+	vcap->format.pixelformat = V4L2_PIX_FMT_RGB24;
+	vcap->format.field = V4L2_FIELD_NONE;
+	vcap->format.colorspace = V4L2_COLORSPACE_SRGB;
+
+	vpix = vimc_pix_map_by_pixelformat(vcap->format.pixelformat);
+
+	vcap->format.bytesperline = vcap->format.width * vpix->bpp;
+	vcap->format.sizeimage = vcap->format.bytesperline *
+				 vcap->format.height;
+
+	/* Fill the vimc_ent_device struct */
+	vcap->ved.destroy = vimc_cap_destroy;
+	vcap->ved.ent = &vcap->vdev.entity;
+	vcap->ved.process_frame = vimc_cap_process_frame;
+
+	/* Initialize the video_device struct */
+	vdev = &vcap->vdev;
+	vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
+	vdev->entity.ops = &vimc_cap_mops;
+	vdev->release = video_device_release_empty;
+	vdev->fops = &vimc_cap_fops;
+	vdev->ioctl_ops = &vimc_cap_ioctl_ops;
+	vdev->lock = &vcap->lock;
+	vdev->queue = q;
+	vdev->v4l2_dev = v4l2_dev;
+	vdev->vfl_dir = VFL_DIR_RX;
+	strlcpy(vdev->name, name, sizeof(vdev->name));
+	video_set_drvdata(vdev, &vcap->ved);
+
+	/* Register the video_device with the v4l2 and the media framework */
+	ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
+	if (ret) {
+		dev_err(vcap->vdev.v4l2_dev->dev,
+			"%s: video register failed (err=%d)\n",
+			vcap->vdev.name, ret);
+		goto err_release_queue;
+	}
+
+	return &vcap->ved;
+
+err_release_queue:
+	vb2_queue_release(q);
+err_clean_m_ent:
+	media_entity_cleanup(&vcap->vdev.entity);
+err_clean_pads:
+	vimc_pads_cleanup(vcap->ved.pads);
+err_free_vcap:
+	kfree(vcap);
+
+	return ERR_PTR(ret);
+}