v4l: vsp1: bru: Support non-premultiplied colors at the BRU output

The BRU outputs premultiplied colors, enable color data normalization
when the format configured at the output of the pipeline isn't
premultiplied.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
(cherry picked from commit 9aca813e1401dcafe1c0a9d3b03795e254571504)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

diff --git a/drivers/media/platform/vsp1/vsp1_bru.c b/drivers/media/platform/vsp1/vsp1_bru.c
index d8d49fb..86b32bc 100644 (file)
--- a/drivers/media/platform/vsp1/vsp1_bru.c
+++ b/drivers/media/platform/vsp1/vsp1_bru.c
@@ -43,8 +43,10 @@ static inline void vsp1_bru_write(struct vsp1_bru *bru, u32 reg, u32 data)
 
 static int bru_s_stream(struct v4l2_subdev *subdev, int enable)
 {
+       struct vsp1_pipeline *pipe = to_vsp1_pipeline(&subdev->entity);
        struct vsp1_bru *bru = to_bru(subdev);
        struct v4l2_mbus_framefmt *format;
+       unsigned int flags;
        unsigned int i;
 
        if (!enable)
@@ -58,8 +60,13 @@ static int bru_s_stream(struct v4l2_subdev *subdev, int enable)
         * to sane default values for now.
         */
 
-       /* Disable both color data normalization and dithering. */
-       vsp1_bru_write(bru, VI6_BRU_INCTRL, 0);
+       /* Disable dithering and enable color data normalization unless the
+        * format at the pipeline output is premultiplied.
+        */
+       flags = pipe->output ? pipe->output->video.format.flags : 0;
+       vsp1_bru_write(bru, VI6_BRU_INCTRL,
+                      flags & V4L2_PIX_FMT_FLAG_PREMUL_ALPHA ?
+                      0 : VI6_BRU_INCTRL_NRM);
 
        /* Set the background position to cover the whole output image and
         * set its color to opaque black.