[PATCH 5/6] media: vsp1: Document max_width restriction on UDS
From: Kieran Bingham
Date: Fri Aug 31 2018 - 10:40:59 EST
The UDS is currently restricted based on a partition size of 256 pixels.
Document the actual restrictions, but don't increase the implementation.
The extended partition algorithm may later choose to utilise a larger
partition size to support overlapping partitions.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
drivers/media/platform/vsp1/vsp1_uds.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/media/platform/vsp1/vsp1_uds.c b/drivers/media/platform/vsp1/vsp1_uds.c
index c20c84b54936..7c11651db5d4 100644
@@ -342,6 +342,14 @@ static unsigned int uds_max_width(struct vsp1_entity *entity,
hscale = output->width / input->width;
+ * The maximum width of the UDS is 304 pixels. These are input pixels
+ * in the event of up-scaling, and output pixels in the event of
+ * downscaling.
+ * To support the current parition algorithm, we clamp at units of 256.
if (hscale <= 2)
else if (hscale <= 4)