Re: [PATCH v18 2/3] drm/ingenic: Implement proper .atomic_get_input_bus_fmts

[Neil Armstrong <narmstrong@baylibre.com>]

On 07/04/2022 13:16, H. Nikolaus Schaller wrote:
> From: Paul Cercueil <paul@crapouillou.net>
> 
> The .atomic_get_input_bus_fmts() callback of our top bridge should
> return the possible input formats for a given output format. If the
> requested output format is not supported, then NULL should be returned,
> otherwise the bus format negociation will end with a bus format that the
> encoder does not support.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
> ---
>   drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 28 ++++++++++++++++++++++-
>   1 file changed, 27 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> index a4f5a323f4906..8eb0ad501a7b9 100644
> --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> @@ -833,6 +833,32 @@ static int ingenic_drm_bridge_atomic_check(struct drm_bridge *bridge,
>   	}
>   }
>   
> +static u32 *
> +ingenic_drm_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
> +					     struct drm_bridge_state *bridge_state,
> +					     struct drm_crtc_state *crtc_state,
> +					     struct drm_connector_state *conn_state,
> +					     u32 output_fmt,
> +					     unsigned int *num_input_fmts)
> +{
> +	switch (output_fmt) {
> +	case MEDIA_BUS_FMT_RGB888_1X24:
> +	case MEDIA_BUS_FMT_RGB666_1X18:
> +	case MEDIA_BUS_FMT_RGB565_1X16:
> +	case MEDIA_BUS_FMT_RGB888_3X8:
> +	case MEDIA_BUS_FMT_RGB888_3X8_DELTA:
> +		break;
> +	default:
> +		*num_input_fmts = 0;
> +		return NULL;
> +	}
> +
> +	return drm_atomic_helper_bridge_propagate_bus_fmt(bridge, bridge_state,
> +							  crtc_state, conn_state,
> +							  output_fmt,
> +							  num_input_fmts);
> +}
> +
>   static irqreturn_t ingenic_drm_irq_handler(int irq, void *arg)
>   {
>   	struct ingenic_drm *priv = drm_device_get_priv(arg);
> @@ -984,7 +1010,7 @@ static const struct drm_bridge_funcs ingenic_drm_bridge_funcs = {
>   	.atomic_reset		= drm_atomic_helper_bridge_reset,
>   	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
>   	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
> -	.atomic_get_input_bus_fmts = drm_atomic_helper_bridge_propagate_bus_fmt,
> +	.atomic_get_input_bus_fmts = ingenic_drm_bridge_atomic_get_input_bus_fmts,
>   };
>   
>   static const struct drm_mode_config_funcs ingenic_drm_mode_config_funcs = {

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