Re: [PATCH v2 06/10] drm/fb-helper: Add support for DRM_FORMAT_C[124]

From: Javier Martinez Canillas
Date: Wed Mar 09 2022 - 08:10:24 EST


On 3/7/22 21:52, Geert Uytterhoeven wrote:
> Add support for color-indexed frame buffer formats with two, four, and
> sixteen colors to the DRM framebuffer helper functions:
> 1. Add support for 1, 2, and 4 bits per pixel to the damage helper,
> 2. For color-indexed modes, the length of the color bitfields must be
> set to the color depth, else the logo code may pick a logo with too
> many colors. Drop the incorrect DAC width comment, which
> originates from the i915 driver.
> 3. Accept C[124] modes when validating or filling in struct
> fb_var_screeninfo, and use the correct number of bits per pixel.
> 4. Set the visual to FB_VISUAL_PSEUDOCOLOR for all color-indexed
> modes.
>
> Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>

[snip]

> static void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
> - uint32_t depth)
> + bool is_color_indexed)
> {
> info->fix.type = FB_TYPE_PACKED_PIXELS;
> - info->fix.visual = depth == 8 ? FB_VISUAL_PSEUDOCOLOR :
> - FB_VISUAL_TRUECOLOR;
> + info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR
> + : info->fix.visual;

Shouldn't this be the following instead ?

+ info->fix.visual = is_color_indexed ? FB_VISUAL_PSEUDOCOLOR
+ : FB_VISUAL_TRUECOLOR;

Other than that the patch looks good to me.

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

--
Best regards,

Javier Martinez Canillas
Linux Engineering
Red Hat