libcamera: v4l2device: Obtain device capabilities

The capabilities structure from the kernel can return capabilities of the
driver, or potentially more specific device capabilities.

Handle this with an inline function 'device_caps()' to return the device
specific capabilities when available, or fall back to the driver capabilities
otherwise.

Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
This commit is contained in:
Kieran Bingham 2019-01-22 18:51:15 +00:00
parent a22dcaaa78
commit e5163f54d4
2 changed files with 16 additions and 3 deletions

View file

@ -26,10 +26,16 @@ struct V4L2Capability final : v4l2_capability {
{
return reinterpret_cast<const char *>(v4l2_capability::bus_info);
}
unsigned int device_caps() const
{
return capabilities & V4L2_CAP_DEVICE_CAPS
? v4l2_capability::device_caps
: v4l2_capability::capabilities;
}
bool isCapture() const { return capabilities & V4L2_CAP_VIDEO_CAPTURE; }
bool isOutput() const { return capabilities & V4L2_CAP_VIDEO_OUTPUT; }
bool hasStreaming() const { return capabilities & V4L2_CAP_STREAMING; }
bool isCapture() const { return device_caps() & V4L2_CAP_VIDEO_CAPTURE; }
bool isOutput() const { return device_caps() & V4L2_CAP_VIDEO_OUTPUT; }
bool hasStreaming() const { return device_caps() & V4L2_CAP_STREAMING; }
};
class MediaEntity;

View file

@ -49,6 +49,13 @@ LOG_DEFINE_CATEGORY(V4L2)
* \return The string containing the device location
*/
/**
* \fn unsigned int V4L2Capability::device_caps()
* \brief Retrieve the capabilities of the device
* \return The device specific capabilities if V4L2_CAP_DEVICE_CAPS is set or
* driver capabilities otherwise
*/
/**
* \fn bool V4L2Capability::isCapture()
* \brief Identify if the device is capable of capturing video