Re: [PATCH] drm/tegra: Remove existing framebuffer only if we support display

[Javier Martinez Canillas <javierm@redhat.com>]

Thierry Reding <thierry.reding@gmail.com> writes:

Hello Thierry,

> From: Thierry Reding <treding@nvidia.com>
>
> Tegra DRM doesn't support display on Tegra234 and later, so make sure
> not to remove any existing framebuffers in that case.
>

I see, this makes sense to me.

Acked-by: Javier Martinez Canillas <javierm@redhat.com>

A couple of comments below though:

> Signed-off-by: Thierry Reding <treding@nvidia.com>
> ---
>  drivers/gpu/drm/tegra/drm.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/tegra/drm.c b/drivers/gpu/drm/tegra/drm.c
> index b1e1a78e30c6..7a38dadbc264 100644
> --- a/drivers/gpu/drm/tegra/drm.c
> +++ b/drivers/gpu/drm/tegra/drm.c
> @@ -1220,9 +1220,11 @@ static int host1x_drm_probe(struct host1x_device *dev)
>  
>  	drm_mode_config_reset(drm);
>  
> -	err = drm_aperture_remove_framebuffers(&tegra_drm_driver);
> -	if (err < 0)
> -		goto hub;
> +	if (drm->mode_config.num_crtc > 0) {

Maybe you can add a comment here explaining why the check is needed?

I also wonder if is worth to move the drm_num_crtcs() function from
drivers/gpu/drm/drm_crtc.c to include/drm/drm_crtc.h and use that helper
instead?

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat