diff mbox series

[v2] drm/stm: ltdc: add layer alpha support

Message ID 20210907151534.6013-1-raphael.gallais-pou@foss.st.com (mailing list archive)
State New, archived
Headers show
Series [v2] drm/stm: ltdc: add layer alpha support | expand

Commit Message

Raphael Gallais-Pou Sept. 7, 2021, 3:15 p.m. UTC 
Android Hardware Composer supports alpha values applied to layers.
Enabling non-opaque layers for the STM CRTC could help offload GPU
resources for screen composition.

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
Acked-by: Yannick Fertre <yannick.fertre@foss.st.com>
Reviewed-by: Yannick Fertre <yannick.fertre@foss.st.com>
---
 drivers/gpu/drm/stm/ltdc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Philippe CORNU Sept. 9, 2021, 1:08 p.m. UTC | #1 
On 9/7/21 5:15 PM, Raphael Gallais-Pou wrote:
> Android Hardware Composer supports alpha values applied to layers.
> Enabling non-opaque layers for the STM CRTC could help offload GPU
> resources for screen composition.
> 
> Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
> Acked-by: Yannick Fertre <yannick.fertre@foss.st.com>
> Reviewed-by: Yannick Fertre <yannick.fertre@foss.st.com>
> ---
>   drivers/gpu/drm/stm/ltdc.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 195de30eb90c..e0fef8bacfa8 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -845,7 +845,7 @@ static void ltdc_plane_atomic_update(struct drm_plane *plane,
>   			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
>   
>   	/* Specifies the constant alpha value */
> -	val = CONSTA_MAX;
> +	val = newstate->alpha >> 8;
>   	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
>   
>   	/* Specifies the blending factors */
> @@ -997,6 +997,8 @@ static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
>   
>   	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
>   
> +	drm_plane_create_alpha_property(plane);
> +
>   	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
>   
>   	return plane;
> 

Applied on drm-misc-next.
Many thanks for your patch,
Philippe :-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 195de30eb90c..e0fef8bacfa8 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -845,7 +845,7 @@  static void ltdc_plane_atomic_update(struct drm_plane *plane,
 			LXCFBLR_CFBLL | LXCFBLR_CFBP, val);
 
 	/* Specifies the constant alpha value */
-	val = CONSTA_MAX;
+	val = newstate->alpha >> 8;
 	reg_update_bits(ldev->regs, LTDC_L1CACR + lofs, LXCACR_CONSTA, val);
 
 	/* Specifies the blending factors */
@@ -997,6 +997,8 @@  static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
 
 	drm_plane_helper_add(plane, &ltdc_plane_helper_funcs);
 
+	drm_plane_create_alpha_property(plane);
+
 	DRM_DEBUG_DRIVER("plane:%d created\n", plane->base.id);
 
 	return plane;