Re: [PATCH 5/6] drm: vkms: Prepare `vkms_wb_encoder_atomic_check` to accept multiple formats

[Thomas Zimmermann]

Hi

Am 05.10.21 um 22:16 schrieb Igor Matheus Andrade Torrente:
> Currently, the vkms atomic check only goes through the first position of
> the `vkms_wb_formats` vector.
>
> This change prepares the atomic_check to check the entire vector.
>
> Signed-off-by: Igor Matheus Andrade Torrente <igormtorrente@xxxxxxxxx>
> ---
>   drivers/gpu/drm/vkms/vkms_writeback.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
> index 5a3e12f105dc..56978f499203 100644
> --- a/drivers/gpu/drm/vkms/vkms_writeback.c
> +++ b/drivers/gpu/drm/vkms/vkms_writeback.c
> @@ -30,6 +30,8 @@ static int vkms_wb_encoder_atomic_check(struct drm_encoder *encoder,
>   {
>   	struct drm_framebuffer *fb;
>   	const struct drm_display_mode *mode = &crtc_state->mode;
> +	bool format_supported = false;
> +	int i;
>   
>   	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
>   		return 0;
> @@ -41,7 +43,14 @@ static int vkms_wb_encoder_atomic_check(struct drm_encoder *encoder,
>   		return -EINVAL;
>   	}
>   
> -	if (fb->format->format != vkms_wb_formats[0]) {
> +	for (i = 0; i < ARRAY_SIZE(vkms_wb_formats); i++) {
> +		if (fb->format->format == vkms_wb_formats[i]) {
> +			format_supported = true;
> +			break;
> +		}
> +	}

At a minimum, this loop should be in a helper function. But more 
generally, I'm surprised that this isn't already covered by the DRM's 
atomic helpers.

Best regards
Thomas

> +
> +	if (!format_supported) {
>   		DRM_DEBUG_KMS("Invalid pixel format %p4cc\n",
>   			      &fb->format->format);
>   		return -EINVAL;

--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer

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