media: vb2: refactor setting flags and caps, fix missing cap

Several functions implementing VIDIOC_REQBUFS and _CREATE_BUFS all use
almost the same code to fill in the flags and capability fields. Refactor
this into a new vb2_set_flags_and_caps() function that replaces the old
fill_buf_caps() and validate_memory_flags() functions.

This also fixes a bug where vb2_ioctl_create_bufs() would not set the
V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS cap and also not fill in the
max_num_buffers field.

Fixes: d055a76c0065 ("media: core: Report the maximum possible number of buffers for the queue")
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
Acked-by: Tomasz Figa <tfiga@chromium.org>

diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c
index 6380155d8575f53b1c1b385e967e2fd063560ea1..c575198e83547ab99719eca7e81dc6e7c0e601d4 100644 (file)
--- a/drivers/media/common/videobuf2/videobuf2-v4l2.c
+++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c
@@ -671,8 +671,20 @@ 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)
+static void vb2_set_flags_and_caps(struct vb2_queue *q, u32 memory,
+                                  u32 *flags, u32 *caps, u32 *max_num_bufs)
 {
+       if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) {
+               /*
+                * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only,
+                * but in order to avoid bugs we zero out all bits.
+                */
+               *flags = 0;
+       } else {
+               /* Clear all unknown flags. */
+               *flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+       }
+
        *caps = V4L2_BUF_CAP_SUPPORTS_ORPHANED_BUFS;
        if (q->io_modes & VB2_MMAP)
                *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP;
@@ -686,21 +698,9 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps)
                *caps |= V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS;
        if (q->supports_requests)
                *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS;
-}
-
-static void validate_memory_flags(struct vb2_queue *q,
-                                 int memory,
-                                 u32 *flags)
-{
-       if (!q->allow_cache_hints || memory != V4L2_MEMORY_MMAP) {
-               /*
-                * This needs to clear V4L2_MEMORY_FLAG_NON_COHERENT only,
-                * but in order to avoid bugs we zero out all bits.
-                */
-               *flags = 0;
-       } else {
-               /* Clear all unknown flags. */
-               *flags &= V4L2_MEMORY_FLAG_NON_COHERENT;
+       if (max_num_bufs) {
+               *max_num_bufs = q->max_num_buffers;
+               *caps |= V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS;
        }
 }
 
@@ -709,8 +709,8 @@ int vb2_reqbufs(struct vb2_queue *q, struct v4l2_requestbuffers *req)
        int ret = vb2_verify_memory_type(q, req->memory, req->type);
        u32 flags = req->flags;
 
-       fill_buf_caps(q, &req->capabilities);
-       validate_memory_flags(q, req->memory, &flags);
+       vb2_set_flags_and_caps(q, req->memory, &flags,
+                              &req->capabilities, NULL);
        req->flags = flags;
        return ret ? ret : vb2_core_reqbufs(q, req->memory,
                                            req->flags, &req->count);
@@ -751,11 +751,9 @@ 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);
-       validate_memory_flags(q, create->memory, &create->flags);
        create->index = vb2_get_num_buffers(q);
-       create->max_num_buffers = q->max_num_buffers;
-       create->capabilities |= V4L2_BUF_CAP_SUPPORTS_MAX_NUM_BUFFERS;
+       vb2_set_flags_and_caps(q, create->memory, &create->flags,
+                              &create->capabilities, &create->max_num_buffers);
        if (create->count == 0)
                return ret != -EBUSY ? ret : 0;
 
@@ -1006,8 +1004,8 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv,
        int res = vb2_verify_memory_type(vdev->queue, p->memory, p->type);
        u32 flags = p->flags;
 
-       fill_buf_caps(vdev->queue, &p->capabilities);
-       validate_memory_flags(vdev->queue, p->memory, &flags);
+       vb2_set_flags_and_caps(vdev->queue, p->memory, &flags,
+                              &p->capabilities, NULL);
        p->flags = flags;
        if (res)
                return res;
@@ -1026,12 +1024,11 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv,
                          struct v4l2_create_buffers *p)
 {
        struct video_device *vdev = video_devdata(file);
-       int res = vb2_verify_memory_type(vdev->queue, p->memory,
-                       p->format.type);
+       int res = vb2_verify_memory_type(vdev->queue, p->memory, p->format.type);
 
        p->index = vb2_get_num_buffers(vdev->queue);
-       fill_buf_caps(vdev->queue, &p->capabilities);
-       validate_memory_flags(vdev->queue, p->memory, &p->flags);
+       vb2_set_flags_and_caps(vdev->queue, p->memory, &p->flags,
+                              &p->capabilities, &p->max_num_buffers);
        /*
         * 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.