[PATCH] drm/meson: Correct OSD1 global alpha value

[Neil Armstrong]

Hi,

Thanks for submitting this patch !

On 08/09/2022 17:51, Stuart Menefy wrote:
> VIU_OSD1_CTRL_STAT.GLOBAL_ALPHA is a 9 bit field, so the maximum
> value is 0x100 not 0xff.

Indeed it's 9bit, but all bits to 1 would be 0x1ff then, but indeed vendor
uses :
#define OSD_GLOBAL_ALPHA_DEF 0x100

> 
> This matches the vendor kernel.
>
Fixes: bbbe775ec5b5 ("drm: Add support for Amlogic Meson Graphic Controller")

> Signed-off-by: Stuart Menefy <stuart.menefy at mathembedded.com>
> ---
>   drivers/gpu/drm/meson/meson_plane.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/meson/meson_plane.c b/drivers/gpu/drm/meson/meson_plane.c
> index d5cbc47..45088f0 100644
> --- a/drivers/gpu/drm/meson/meson_plane.c
> +++ b/drivers/gpu/drm/meson/meson_plane.c
> @@ -163,7 +163,7 @@ static void meson_plane_atomic_update(struct drm_plane *plane,
>   
>   	/* Enable OSD and BLK0, set max global alpha */
>   	priv->viu.osd1_ctrl_stat = OSD_ENABLE |
> -				   (0xFF << OSD_GLOBAL_ALPHA_SHIFT) |
> +				   (0x100 << OSD_GLOBAL_ALPHA_SHIFT) |
>   				   OSD_BLK0_ENABLE;
>   
>   	priv->viu.osd1_ctrl_stat2 = readl(priv->io_base +

Reviewed-by: Neil Armstrong <narmstrong at baylibre.com>