media: vb2: set reqbufs/create_bufs capabilities

Set the capabilities field of v4l2_requestbuffers and v4l2_create_buffers.

The various mapping modes were easy, but for signaling the request capability
a new 'supports_requests' bitfield was added to videobuf2-core.h (and set in
vim2m and vivid). Drivers have to set this bitfield for any queue where
requests are supported.

Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/common/videobuf2/videobuf2-v4l2.c

@@ -384,7 +384,7 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md
 			return -EPERM;
 		}
 		return 0;
-	} else if (q->uses_qbuf) {
+	} else if (q->uses_qbuf || !q->supports_requests) {
 		dprintk(1, "%s: queue does not use requests\n", opname);
 		return -EPERM;
 	}
@@ -619,10 +619,24 @@ int vb2_querybuf(struct vb2_queue *q, struct v4l2_buffer *b)
 }
 EXPORT_SYMBOL(vb2_querybuf);
 
+static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
+{
+	*caps = 0;
+	if (q->io_modes & VB2_MMAP)
+		*caps |= V4L2_BUF_CAP_SUPPORTS_MMAP;
+	if (q->io_modes & VB2_USERPTR)
+		*caps |= V4L2_BUF_CAP_SUPPORTS_USERPTR;
+	if (q->io_modes & VB2_DMABUF)
+		*caps |= V4L2_BUF_CAP_SUPPORTS_DMABUF;
+	if (q->supports_requests)
+		*caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS;
+}
+
 int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
 {
 	int ret = vb2_verify_memory_type(q, req->memory, req->type);
 
+	fill_buf_caps(q, &req->capabilities);
 	return ret ? ret : vb2_core_reqbufs(q, req->memory, &req->count);
 }
 EXPORT_SYMBOL_GPL(vb2_reqbufs);
@@ -654,6 +668,7 @@ int vb2_create_bufs(struct vb2_queue *q, struct v4l2_create_buffers *create)
 	int ret = vb2_verify_memory_type(q, create->memory, f->type);
 	unsigned i;
 
+	fill_buf_caps(q, &create->capabilities);
 	create->index = q->num_buffers;
 	if (create->count == 0)
 		return ret != -EBUSY ? ret : 0;
@@ -861,6 +876,7 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv,
 	struct video_device *vdev = video_devdata(file);
 	int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type);
 
+	fill_buf_caps(vdev->queue, &p->capabilities);
 	if (res)
 		return res;
 	if (vb2_queue_is_busy(vdev, file))
@@ -882,6 +898,7 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv,
 			p->format.type);
 
 	p->index = vdev->queue->num_buffers;
+	fill_buf_caps(vdev->queue, &p->capabilities);
 	/*
 	 * If count == 0, then just check if memory and type are valid.
 	 * Any -EBUSY result from vb2_verify_memory_type can be mapped to 0.

drivers/media/platform/vim2m.c

@@ -855,6 +855,7 @@ static int queue_init(void *priv, struct vb2_queue *src_vq, struct vb2_queue *ds
 	src_vq->mem_ops = &vb2_vmalloc_memops;
 	src_vq->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_COPY;
 	src_vq->lock = &ctx->dev->dev_mutex;
+	src_vq->supports_requests = true;
 
 	ret = vb2_queue_init(src_vq);
 	if (ret)

drivers/media/platform/vivid/vivid-core.c

@@ -1077,6 +1077,7 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
 		q->min_buffers_needed = 2;
 		q->lock = &dev->mutex;
 		q->dev = dev->v4l2_dev.dev;
+		q->supports_requests = true;
 
 		ret = vb2_queue_init(q);
 		if (ret)
@@ -1097,6 +1098,7 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
 		q->min_buffers_needed = 2;
 		q->lock = &dev->mutex;
 		q->dev = dev->v4l2_dev.dev;
+		q->supports_requests = true;
 
 		ret = vb2_queue_init(q);
 		if (ret)
@@ -1117,6 +1119,7 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
 		q->min_buffers_needed = 2;
 		q->lock = &dev->mutex;
 		q->dev = dev->v4l2_dev.dev;
+		q->supports_requests = true;
 
 		ret = vb2_queue_init(q);
 		if (ret)
@@ -1137,6 +1140,7 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
 		q->min_buffers_needed = 2;
 		q->lock = &dev->mutex;
 		q->dev = dev->v4l2_dev.dev;
+		q->supports_requests = true;
 
 		ret = vb2_queue_init(q);
 		if (ret)
@@ -1156,6 +1160,7 @@ static int vivid_create_instance(struct platform_device *pdev, int inst)
 		q->min_buffers_needed = 8;
 		q->lock = &dev->mutex;
 		q->dev = dev->v4l2_dev.dev;
+		q->supports_requests = true;
 
 		ret = vb2_queue_init(q);
 		if (ret)

drivers/media/v4l2-core/v4l2-compat-ioctl32.c

@@ -251,7 +251,8 @@ struct v4l2_create_buffers32 {
 	__u32			count;
 	__u32			memory;	/* enum v4l2_memory */
 	struct v4l2_format32	format;
-	__u32			reserved[8];
+	__u32			capabilities;
+	__u32			reserved[7];
 };
 
 static int __bufsize_v4l2_format(struct v4l2_format32 __user *p32, u32 *size)
@@ -411,6 +412,7 @@ static int put_v4l2_create32(struct v4l2_create_buffers __user *p64,
 	if (!access_ok(VERIFY_WRITE, p32, sizeof(*p32)) ||
 	    copy_in_user(p32, p64,
 			 offsetof(struct v4l2_create_buffers32, format)) ||
+	    assign_in_user(&p32->capabilities, &p64->capabilities) ||
 	    copy_in_user(p32->reserved, p64->reserved, sizeof(p64->reserved)))
 		return -EFAULT;
 	return __put_v4l2_format32(&p64->format, &p32->format);

drivers/media/v4l2-core/v4l2-ioctl.c

@@ -1877,7 +1877,7 @@ static int v4l_reqbufs(const struct v4l2_ioctl_ops *ops,
 	if (ret)
 		return ret;
 
-	CLEAR_AFTER_FIELD(p, memory);
+	CLEAR_AFTER_FIELD(p, capabilities);
 
 	return ops->vidioc_reqbufs(file, fh, p);
 }
@@ -1918,7 +1918,7 @@ static int v4l_create_bufs(const struct v4l2_ioctl_ops *ops,
 	if (ret)
 		return ret;
 
-	CLEAR_AFTER_FIELD(create, format);
+	CLEAR_AFTER_FIELD(create, capabilities);
 
 	v4l_sanitize_format(&create->format);
 

include/media/videobuf2-core.h

@@ -472,6 +472,7 @@ struct vb2_buf_ops {
  * @quirk_poll_must_check_waiting_for_buffers: Return %EPOLLERR at poll when QBUF
  *              has not been called. This is a vb1 idiom that has been adopted
  *              also by vb2.
+ * @supports_requests: this queue supports the Request API.
  * @uses_qbuf:	qbuf was used directly for this queue. Set to 1 the first
  *		time this is called. Set to 0 when the queue is canceled.
  *		If this is 1, then you cannot queue buffers from a request.
@@ -545,6 +546,7 @@ struct vb2_queue {
 	unsigned			fileio_write_immediately:1;
 	unsigned			allow_zero_bytesused:1;
 	unsigned		   quirk_poll_must_check_waiting_for_buffers:1;
+	unsigned			supports_requests:1;
 	unsigned			uses_qbuf:1;
 	unsigned			uses_requests:1;