Re: [PATCH 1/2] video: vga16fb: Fix logic that checks for the display standard

From: Geert Uytterhoeven
Date: Sun Jan 09 2022 - 05:02:39 EST


Hi Javier,

On Fri, Jan 7, 2022 at 9:00 PM Javier Martinez Canillas
<javierm@xxxxxxxxxx> wrote:
> The vga16fb framebuffer driver supports both Enhanced Graphics Adapter
> (EGA) and Video Graphics Array (VGA) 16 color graphic cards.
>
> But the logic to check whether the EGA or VGA standard are used is not
> correct. It just checks if screen_info.orig_video_isVGA is set, but it
> should check if is set to VIDEO_TYPE_VGAC instead.
>
> This means that it assumes to be VGA even if is set to VIDEO_TYPE_EGAC.
>
> Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>

Thanks for your patch!

> --- a/drivers/video/fbdev/vga16fb.c
> +++ b/drivers/video/fbdev/vga16fb.c
> @@ -1332,7 +1332,7 @@ static int vga16fb_probe(struct platform_device *dev)
> printk(KERN_INFO "vga16fb: mapped to 0x%p\n", info->screen_base);
> par = info->par;
>
> - par->isVGA = screen_info.orig_video_isVGA;
> + par->isVGA = screen_info.orig_video_isVGA == VIDEO_TYPE_VGAC;

All non-x86 architectures (except for 2 MIPS platforms) treat
orig_video_isVGA as a boolean flag, and just assign 1 to it.
Hence this change would break them.

> par->palette_blanked = 0;
> par->vesa_blanked = 0;
>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds