[PATCH 09/10] drm/vc4: Use __drm_atomic_helper_plane_reset instead of copying the logic

Hi Maxime,

On Tue, Jul 24, 2018 at 08:57:20AM +0200, Maxime Ripard wrote:

On Fri, Jul 20, 2018 at 10:15:08PM +0100, Alexandru Gheorghe wrote:

quoted

Signed-off-by: Alexandru Gheorghe <redacted>
---
 drivers/gpu/drm/vc4/vc4_plane.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c
index 9d7a36f148cf..688ad9bb0f08 100644
--- a/drivers/gpu/drm/vc4/vc4_plane.c
+++ b/drivers/gpu/drm/vc4/vc4_plane.c

@@ -200,9 +200,7 @@ static void vc4_plane_reset(struct drm_plane *plane)
 	if (!vc4_state)
 		return;
 
-	plane->state = &vc4_state->base;
-	plane->state->alpha = DRM_BLEND_ALPHA_OPAQUE;
-	vc4_state->base.plane = plane;
+	__drm_atomic_helper_plane_reset(plane, &vc4_state->base);

For vc4, rcar-du, atmel-hlcdc and sun4i, you're changing the reset
value of alpha from DRM_BLEND_ALPHA_OPAQUE to
plane->alpha_property->values[1].

plane->alpha_property->values[1] holds the max value for alpha, and
it's initialized by the core to DRM_BLEND_ALPHA_OPAQUE.

This might or might not be a good idea, but you should definitely
explain why.

Would a commit message suffice? Or do you have other ideas?

Maxime

-- 
Maxime Ripard, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
https://bootlin.com

-- 
Cheers,
Alex G