[PATCH v8 3/8] media: add V4L2_CTRL_TYPE_AREA control type

From: Ricardo Ribalda Delgado
Date: Mon Sep 30 2019 - 06:18:56 EST


From: Ricardo Ribalda Delgado <ricardo@xxxxxxxxxxx>

This type contains the width and the height of a rectangular area.

Reviewed-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
Signed-off-by: Ricardo Ribalda Delgado <ribalda@xxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-ctrls.c | 21 ++++++++++++++
include/media/v4l2-ctrls.h | 42 ++++++++++++++++++++++++++++
include/uapi/linux/videodev2.h | 6 ++++
3 files changed, 69 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 219d8aeefa20..b9a46f536406 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1678,6 +1678,7 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
struct v4l2_ctrl_mpeg2_slice_params *p_mpeg2_slice_params;
struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
void *p = ptr.p + idx * ctrl->elem_size;
+ struct v4l2_area *area;

switch ((u32)ctrl->type) {
case V4L2_CTRL_TYPE_MPEG2_SLICE_PARAMS:
@@ -1753,6 +1754,11 @@ static int std_validate_compound(const struct v4l2_ctrl *ctrl, u32 idx,
zero_padding(p_vp8_frame_header->entropy_header);
zero_padding(p_vp8_frame_header->coder_state);
break;
+ case V4L2_CTRL_TYPE_AREA:
+ area = p;
+ if (!area->width || !area->height)
+ return -EINVAL;
+ break;
default:
return -EINVAL;
}
@@ -2427,6 +2433,9 @@ static struct v4l2_ctrl *v4l2_ctrl_new(struct v4l2_ctrl_handler *hdl,
case V4L2_CTRL_TYPE_VP8_FRAME_HEADER:
elem_size = sizeof(struct v4l2_ctrl_vp8_frame_header);
break;
+ case V4L2_CTRL_TYPE_AREA:
+ elem_size = sizeof(struct v4l2_area);
+ break;
default:
if (type < V4L2_CTRL_COMPOUND_TYPES)
elem_size = sizeof(s32);
@@ -4116,6 +4125,18 @@ int __v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
}
EXPORT_SYMBOL(__v4l2_ctrl_s_ctrl_string);

+int __v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+ const struct v4l2_area *area)
+{
+ lockdep_assert_held(ctrl->handler->lock);
+
+ /* It's a driver bug if this happens. */
+ WARN_ON(ctrl->type != V4L2_CTRL_TYPE_AREA);
+ memcpy(ctrl->p_new.p_area, area, sizeof(*area));
+ return set_ctrl(NULL, ctrl, 0);
+}
+EXPORT_SYMBOL(__v4l2_ctrl_s_ctrl_area);
+
void v4l2_ctrl_request_complete(struct media_request *req,
struct v4l2_ctrl_handler *main_hdl)
{
diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
index 90a8ee48c2f3..c42f164e2c9e 100644
--- a/include/media/v4l2-ctrls.h
+++ b/include/media/v4l2-ctrls.h
@@ -50,6 +50,7 @@ struct poll_table_struct;
* @p_h264_slice_params: Pointer to a struct v4l2_ctrl_h264_slice_params.
* @p_h264_decode_params: Pointer to a struct v4l2_ctrl_h264_decode_params.
* @p_vp8_frame_header: Pointer to a VP8 frame header structure.
+ * @p_area: Pointer to an area.
* @p: Pointer to a compound value.
*/
union v4l2_ctrl_ptr {
@@ -68,6 +69,7 @@ union v4l2_ctrl_ptr {
struct v4l2_ctrl_h264_slice_params *p_h264_slice_params;
struct v4l2_ctrl_h264_decode_params *p_h264_decode_params;
struct v4l2_ctrl_vp8_frame_header *p_vp8_frame_header;
+ struct v4l2_area *p_area;
void *p;
};

@@ -1086,6 +1088,46 @@ static inline int v4l2_ctrl_s_ctrl_string(struct v4l2_ctrl *ctrl, const char *s)
return rval;
}

+/**
+ * __v4l2_ctrl_s_ctrl_area() - Unlocked variant of v4l2_ctrl_s_ctrl_area().
+ *
+ * @ctrl: The control.
+ * @area: The new area.
+ *
+ * This sets the control's new area safely by going through the control
+ * framework. This function assumes the control's handler is already locked,
+ * allowing it to be used from within the &v4l2_ctrl_ops functions.
+ *
+ * This function is for area type controls only.
+ */
+int __v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+ const struct v4l2_area *area);
+
+/**
+ * v4l2_ctrl_s_ctrl_area() - Helper function to set a control's area value
+ * from within a driver.
+ *
+ * @ctrl: The control.
+ * @s: The new area.
+ *
+ * This sets the control's new area safely by going through the control
+ * framework. This function will lock the control's handler, so it cannot be
+ * used from within the &v4l2_ctrl_ops functions.
+ *
+ * This function is for area type controls only.
+ */
+static inline int v4l2_ctrl_s_ctrl_area(struct v4l2_ctrl *ctrl,
+ const struct v4l2_area *area)
+{
+ int rval;
+
+ v4l2_ctrl_lock(ctrl);
+ rval = __v4l2_ctrl_s_ctrl_area(ctrl, area);
+ v4l2_ctrl_unlock(ctrl);
+
+ return rval;
+}
+
/* Internal helper functions that deal with control events. */
extern const struct v4l2_subscribed_event_ops v4l2_ctrl_sub_ev_ops;

diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 530638dffd93..b3c0961b62a0 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -422,6 +422,11 @@ struct v4l2_fract {
__u32 denominator;
};

+struct v4l2_area {
+ __u32 width;
+ __u32 height;
+};
+
/**
* struct v4l2_capability - Describes V4L2 device caps returned by VIDIOC_QUERYCAP
*
@@ -1720,6 +1725,7 @@ enum v4l2_ctrl_type {
V4L2_CTRL_TYPE_U8 = 0x0100,
V4L2_CTRL_TYPE_U16 = 0x0101,
V4L2_CTRL_TYPE_U32 = 0x0102,
+ V4L2_CTRL_TYPE_AREA = 0x0106,
};

/* Used in the VIDIOC_QUERYCTRL ioctl for querying controls */
--
2.23.0