[RESENT PATCH V0 1/4] media: v4l2-core: extend the v4l2 format to support request

From: Louis Kuo
Date: Fri May 07 2021 - 03:46:29 EST


This patch is to extend the related interface to support the request-based
operations. We added request fd to the parameters of MEDIA_IOC_SETUP_LINK,
VIDIOC_S_FMT, VIDIOC_SUBDEV_S_SELECTION, VIDIOC_SUBDEV_S_FMT.
The driver uses media_request_get_by_fd() to retrieve the media request and
save the pending change in it, so that we can apply the pending change in
req_queue() callback then.

Signed-off-by: Louis Kuo <louis.kuo@xxxxxxxxxxxx>
---
drivers/media/mc/mc-device.c | 7 ++++++-
drivers/media/v4l2-core/v4l2-ioctl.c | 8 ++++----
include/media/media-entity.h | 3 +++
include/uapi/linux/media.h | 3 ++-
include/uapi/linux/v4l2-subdev.h | 3 ++-
include/uapi/linux/videodev2.h | 8 ++++++--
6 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/drivers/media/mc/mc-device.c b/drivers/media/mc/mc-device.c
index 9e56d2ad6b94..f46ae4c38102 100644
--- a/drivers/media/mc/mc-device.c
+++ b/drivers/media/mc/mc-device.c
@@ -203,6 +203,7 @@ static long media_device_setup_link(struct media_device *mdev, void *arg)
struct media_link *link = NULL;
struct media_entity *source;
struct media_entity *sink;
+ int ret;

/* Find the source and sink entities and link.
*/
@@ -221,10 +222,14 @@ static long media_device_setup_link(struct media_device *mdev, void *arg)
if (link == NULL)
return -EINVAL;

+ link->request_fd = linkd->request_fd;
memset(linkd->reserved, 0, sizeof(linkd->reserved));

/* Setup the link on both entities. */
- return __media_entity_setup_link(link, linkd->flags);
+ ret = __media_entity_setup_link(link, linkd->flags);
+ link->request_fd = 0;
+
+ return ret;
}

static long media_device_get_topology(struct media_device *mdev, void *arg)
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 2673f51aafa4..823ebd175f3a 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1634,7 +1634,7 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
if (unlikely(!ops->vidioc_s_fmt_vid_cap_mplane))
break;
- CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
+ CLEAR_AFTER_FIELD(p, fmt.pix_mp.request_fd);
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@@ -1665,7 +1665,7 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
if (unlikely(!ops->vidioc_s_fmt_vid_out_mplane))
break;
- CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
+ CLEAR_AFTER_FIELD(p, fmt.pix_mp.request_fd);
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@@ -1736,7 +1736,7 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
case V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE:
if (unlikely(!ops->vidioc_try_fmt_vid_cap_mplane))
break;
- CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
+ CLEAR_AFTER_FIELD(p, fmt.pix_mp.request_fd);
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@@ -1767,7 +1767,7 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
case V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE:
if (unlikely(!ops->vidioc_try_fmt_vid_out_mplane))
break;
- CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
+ CLEAR_AFTER_FIELD(p, fmt.pix_mp.request_fd);
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
diff --git a/include/media/media-entity.h b/include/media/media-entity.h
index 09737b47881f..30ad665c4413 100644
--- a/include/media/media-entity.h
+++ b/include/media/media-entity.h
@@ -128,6 +128,8 @@ struct media_pipeline {
* link.
* @flags: Link flags, as defined in uapi/media.h (MEDIA_LNK_FL_*)
* @is_backlink: Indicate if the link is a backlink.
+ * @request_fd: The media request triggered the media link change, it is only
+ * meaningful in media_device_setup_link()
*/
struct media_link {
struct media_gobj graph_obj;
@@ -145,6 +147,7 @@ struct media_link {
struct media_link *reverse;
unsigned long flags;
bool is_backlink;
+ int request_fd;
};

/**
diff --git a/include/uapi/linux/media.h b/include/uapi/linux/media.h
index 200fa8462b90..a331f80afe2d 100644
--- a/include/uapi/linux/media.h
+++ b/include/uapi/linux/media.h
@@ -231,7 +231,8 @@ struct media_link_desc {
struct media_pad_desc source;
struct media_pad_desc sink;
__u32 flags;
- __u32 reserved[2];
+ __s32 request_fd;
+ __u32 reserved[1];
};

struct media_links_enum {
diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
index 658106f5b5dc..d6ffd5981c68 100644
--- a/include/uapi/linux/v4l2-subdev.h
+++ b/include/uapi/linux/v4l2-subdev.h
@@ -50,7 +50,8 @@ struct v4l2_subdev_format {
__u32 which;
__u32 pad;
struct v4l2_mbus_framefmt format;
- __u32 reserved[8];
+ __s32 request_fd;
+ __u32 reserved[7];
};

/**
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 311a01cc5775..6641194b3fab 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -1246,6 +1246,7 @@ struct v4l2_crop {
* defined in v4l2-common.h; V4L2_SEL_TGT_* .
* @flags: constraints flags, defined in v4l2-common.h; V4L2_SEL_FLAG_*.
* @r: coordinates of selection window
+ * @request_fd: fd of the request that trigger the set selection operation
* @reserved: for future use, rounds structure size to 64 bytes, set to zero
*
* Hardware may use multiple helper windows to process a video stream.
@@ -1257,7 +1258,8 @@ struct v4l2_selection {
__u32 target;
__u32 flags;
struct v4l2_rect r;
- __u32 reserved[9];
+ __s32 request_fd;
+ __u32 reserved[8];
};


@@ -2266,6 +2268,7 @@ struct v4l2_plane_pix_format {
* @hsv_enc: enum v4l2_hsv_encoding, HSV encoding
* @quantization: enum v4l2_quantization, colorspace quantization
* @xfer_func: enum v4l2_xfer_func, colorspace transfer function
+ * @request_fd: fd of the request that trigger the set format operation
* @reserved: drivers and applications must zero this array
*/
struct v4l2_pix_format_mplane {
@@ -2284,7 +2287,8 @@ struct v4l2_pix_format_mplane {
};
__u8 quantization;
__u8 xfer_func;
- __u8 reserved[7];
+ __s32 request_fd;
+ __u8 reserved[3];
} __attribute__ ((packed));

/**
--
2.18.0