add max_interval and step_interval to struct
v4l2_subdev_frame_interval_enum.
When filled correctly by the sensor driver, those fields must be
used as follows by the intermediate level :
struct v4l2_frmivalenum *fival;
struct v4l2_subdev_frame_interval_enum fie;
if (fie.max_interval.numerator == 0) {
fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
fival->discrete = fie.interval;
} else if (fie.step_interval.numerator == 0) {
fival->type = V4L2_FRMIVAL_TYPE_CONTINUOUS;
fival->stepwise.min = fie.interval;
fival->stepwise.max = fie.max_interval;
} else {
fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
fival->stepwise.min = fie.interval;
fival->stepwise.max = fie.max_interval;
fival->stepwise.step = fie.step_interval;
}
Signed-off-by: Philippe De Muyter <phdm@xxxxxxxxx>
---
.../uapi/v4l/vidioc-subdev-enum-frame-interval.rst | 39 +++++++++++++++++++++-
include/uapi/linux/v4l2-subdev.h | 4 ++-
2 files changed, 41 insertions(+), 2 deletions(-)
diff --git a/Documentation/media/uapi/v4l/vidioc-subdev-enum-frame-interval.rst b/Documentation/media/uapi/v4l/vidioc-subdev-enum-frame-interval.rst
index 1bfe386..acc516e 100644
--- a/Documentation/media/uapi/v4l/vidioc-subdev-enum-frame-interval.rst
+++ b/Documentation/media/uapi/v4l/vidioc-subdev-enum-frame-interval.rst
@@ -51,6 +51,37 @@ EINVAL error code if one of the input fields is invalid. All frame
intervals are enumerable by beginning at index zero and incrementing by
one until ``EINVAL`` is returned.
+If the sub-device can work only at the fixed set of frame intervals,
+driver must enumerate them with increasing indexes, by only filling
+the ``interval`` field. If the sub-device can work with a continuous
+range of frame intervals, driver must only return success for index 0
+and fill ``interval`` with the minimum interval, ``max_interval`` with
+the maximum interval, and ``step_interval`` with 0 or the step between
+the possible intervals.
+
+Callers are expected to use the returned information as follows :
+
+.. code-block:: c
+
+ struct v4l2_frmivalenum * fival;
+ struct v4l2_subdev_frame_interval_enum fie;
+
+ if (fie.max_interval.numerator == 0) {
+ fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+ fival->discrete = fie.interval;
+ } else if (fie.step_interval.numerator == 0) {
+ fival->type = V4L2_FRMIVAL_TYPE_CONTINUOUS;
+ fival->stepwise.min = fie.interval;
+ fival->stepwise.max = fie.max_interval;
+ } else {
+ fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
+ fival->stepwise.min = fie.interval;
+ fival->stepwise.max = fie.max_interval;
+ fival->stepwise.step = fie.step_interval;
+ }
+
+.. code-block:: c
+
Available frame intervals may depend on the current 'try' formats at
other pads of the sub-device, as well as on the current active links.
See :ref:`VIDIOC_SUBDEV_G_FMT` for more
@@ -92,8 +123,14 @@ multiple pads of the same sub-device is not defined.
- ``which``
- Frame intervals to be enumerated, from enum
:ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
+ * - struct :c:type:`v4l2_fract`
+ - ``max_interval``
+ - Maximum period, in seconds, between consecutive video frames, or 0.
+ * - struct :c:type:`v4l2_fract`
+ - ``step_interval``
+ - Frame interval step size, in seconds, or 0.
* - __u32
- - ``reserved``\ [8]
+ - ``reserved``\ [4]
- Reserved for future extensions. Applications and drivers must set
the array to zero.
diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
index 03970ce..c944644 100644
--- a/include/uapi/linux/v4l2-subdev.h
+++ b/include/uapi/linux/v4l2-subdev.h
@@ -128,7 +128,9 @@ struct v4l2_subdev_frame_interval_enum {
__u32 height;
struct v4l2_fract interval;
__u32 which;
- __u32 reserved[8];
+ struct v4l2_fract max_interval;
+ struct v4l2_fract step_interval;
+ __u32 reserved[4];
};
/**
--
1.8.4
