Re: [PATCH 1/5] drm/format-helper: Rename drm_fb_xrgb8888_to_mono_reversed()

[Javier Martinez Canillas]

Hello Geert,

Thanks for your patch.

On 3/15/22 12:07, Geert Uytterhoeven wrote:
> There is no "reversed" handling in drm_fb_xrgb8888_to_mono_reversed():
> the function just converts from color to grayscale, and reduces the
> number of grayscale levels from 256 to 2 (i.e. brightness 0-127 is
> mapped to 0, 128-255 to 1).  All "reversed" handling is done in the
> repaper driver, where this function originated.
> 
> Hence make this clear by renaming drm_fb_xrgb8888_to_mono_reversed() to
> drm_fb_xrgb8888_to_mono(), and documenting the black/white pixel
> mapping.
> 
> Fixes: bcf8b616deb87941 ("drm/format-helper: Add drm_fb_xrgb8888_to_mono_reversed()")
> Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> ---
As you mentioned the function originally came from the repaper driver
(that uses white-on-black) and I wrongly assumed that the destination
buffer for the OLED panels were also monochrome reversed.

Acked-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>

-- 
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat