Support enabling the histogram statistics engine and retrieving
histogram data. Histogram data is currently ignored in the image quality
tuning implementation.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Most functions return 0 on success and a negative error code otherwise,
make vo_queue_buffer() conform with that.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

The omap_vout driver implements the output overlay API, use the
corresponding buffer type.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

valgrind has no way to know that the kernel will fill links and pads
arrays passed to an ioctl through __user pointers. Allocate the arrays
with calloc() to make sure they get initialized. This also fixes the
potential integer overflow.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Events callback can call events_unwatch_fd(), resulting in the event
being deleted from the events list. Use list_for_each_entry_safe() to
walk the list properly, and make sure the event isn't accessed after
it's callback function returns.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Don't try to force the sensor format or the output format at the
pipeline input when using memory-to-memory pipelines.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

When using sensor scaling the sensor was incorrectly configured to crop
the image to a lower size instead of scaling it. Cropping is applied
before scaling in the sensor, so the crop rectangle needs to be set to
the pipeline input size, not the sensor output size.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>