[PATCH v2 2/5] drm/omap: use degamma property for gamma table

Laurent Pinchart laurent.pinchart at ideasonboard.com
Mon Nov 30 10:39:03 UTC 2020


Hi Tomi,

Thank you for the patch.

On Tue, Nov 03, 2020 at 10:03:07AM +0200, Tomi Valkeinen wrote:
> omapdrm supports gamma via GAMMA_LUT property. However, the HW we have
> is:
> 
> gamma -> ctm -> out
> 
> instead of what the model DRM framework uses:
> 
> ctm -> gamma -> out
> 
> As the following patches add CTM support for omapdrm, lets first fix the
> gamma.
> 
> This patch changes the property from GAMMA_LUT to DEGAMMA_LUT, and uses
> drm_atomic_helper_legacy_degamma_set for gamma_set helper. Thus we will
> have:
> 
> degamma -> ctm -> out
> 
> and the legacy ioctl will continue working as before.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> Reviewed-by: Pekka Paalanen <pekka.paalanen at collabora.com>

Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
>  drivers/gpu/drm/omapdrm/omap_crtc.c | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c
> index d7442aa55f89..d40220b2f312 100644
> --- a/drivers/gpu/drm/omapdrm/omap_crtc.c
> +++ b/drivers/gpu/drm/omapdrm/omap_crtc.c
> @@ -575,8 +575,8 @@ static int omap_crtc_atomic_check(struct drm_crtc *crtc,
>  									  crtc);
>  	struct drm_plane_state *pri_state;
>  
> -	if (crtc_state->color_mgmt_changed && crtc_state->gamma_lut) {
> -		unsigned int length = crtc_state->gamma_lut->length /
> +	if (crtc_state->color_mgmt_changed && crtc_state->degamma_lut) {
> +		unsigned int length = crtc_state->degamma_lut->length /
>  			sizeof(struct drm_color_lut);
>  
>  		if (length < 2)
> @@ -617,10 +617,10 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
>  		struct drm_color_lut *lut = NULL;
>  		unsigned int length = 0;
>  
> -		if (crtc->state->gamma_lut) {
> +		if (crtc->state->degamma_lut) {
>  			lut = (struct drm_color_lut *)
> -				crtc->state->gamma_lut->data;
> -			length = crtc->state->gamma_lut->length /
> +				crtc->state->degamma_lut->data;
> +			length = crtc->state->degamma_lut->length /
>  				sizeof(*lut);
>  		}
>  		priv->dispc_ops->mgr_set_gamma(priv->dispc, omap_crtc->channel,
> @@ -741,7 +741,7 @@ static const struct drm_crtc_funcs omap_crtc_funcs = {
>  	.set_config = drm_atomic_helper_set_config,
>  	.destroy = omap_crtc_destroy,
>  	.page_flip = drm_atomic_helper_page_flip,
> -	.gamma_set = drm_atomic_helper_legacy_gamma_set,
> +	.gamma_set = drm_atomic_helper_legacy_degamma_set,
>  	.atomic_duplicate_state = omap_crtc_duplicate_state,
>  	.atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
>  	.atomic_set_property = omap_crtc_atomic_set_property,
> @@ -842,7 +842,7 @@ struct drm_crtc *omap_crtc_init(struct drm_device *dev,
>  	if (priv->dispc_ops->mgr_gamma_size(priv->dispc, channel)) {
>  		unsigned int gamma_lut_size = 256;
>  
> -		drm_crtc_enable_color_mgmt(crtc, 0, false, gamma_lut_size);
> +		drm_crtc_enable_color_mgmt(crtc, gamma_lut_size, false, 0);
>  		drm_mode_crtc_set_gamma_size(crtc, gamma_lut_size);
>  	}
>  
> 

-- 
Regards,

Laurent Pinchart


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