[PATCH 2/2] drm/fb-helper: Don't load the display palette if the CRTC is disabled

[Ville Syrjälä]

On Mon, May 27, 2013 at 06:44:57PM +0300, ville.syrjala at linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> Often the hardware needs certain clocks running when accessing the
> palette, so don't go poking at it if the CRTC is disabled. We still
> call the fb_helper gamma_set hooks to update the driver's notion of
> what the palette should contain, so that if/when CRTC gets enabled,
> the driver will load the correct palette.
> 
> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> ---
> The other option would of course to put the check into the load_lut
> function itself. I don't really care which way we do it as long as
> the check is somewhere...

And I just realized we already have the check in i915 load_lut at least.
Not sure how I failed to notice it before. So feel free to ignore this
patch. Patch 1/2 still seems relevant though.

> 
>  drivers/gpu/drm/drm_fb_helper.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 1b6ca23..4ecf128 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -663,7 +663,9 @@ int drm_fb_helper_setcmap(struct fb_cmap *cmap, struct fb_info *info)
>  			if (rc)
>  				goto out;
>  		}
> -		crtc_funcs->load_lut(crtc);
> +
> +		if (crtc->enabled)
> +			crtc_funcs->load_lut(crtc);
>  	}
>   out:
>  	drm_modeset_unlock_all(dev);
> -- 
> 1.8.1.5

-- 
Ville Syrjälä
Intel OTC