Re: [PATCH 05/17] DRM/KMS/EDID: Fix up EEDID Map Blocks if Extension block count has changed.

From: Takashi Iwai <tiwai@suse.de>
To: Egbert Eich <eich@novell.com>
Cc: dri-devel@lists.freedesktop.org
Subject: Re: [PATCH 05/17] DRM/KMS/EDID: Fix up EEDID Map Blocks if Extension block count has changed.
Date: Tue, 20 Nov 2012 09:13:35 +0100	[thread overview]
Message-ID: <s5hwqxgpu8g.wl%tiwai@suse.de> (raw)
In-Reply-To: <1353356598-10634-6-git-send-email-eich@suse.de>

At Mon, 19 Nov 2012 15:23:06 -0500,
"Egbert Eich " <"eich@novell.com> wrote:
> 
> EEDID v1.3 mandates map blocks if more than one EDID extension block
> is used while in v1.4 they are optional.
> If the extension count has been changed (because some extension
> blocks were not readable) those map blocks need fixing.
> In case of v1.4 or higher we simply eliminate all map blocks as
> this is less time consuming. For v1.3 we scrap any exsisting map
> blocks and recreate them from scratch.
> 
> Signed-off-by: Egbert Eich <eich@suse.de>
> ---
>  drivers/gpu/drm/drm_edid.c |  105 +++++++++++++++++++++++++++++++++++++++++--
>  1 files changed, 100 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index ec6f3bb..d1b9d67 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -44,7 +44,11 @@
>  #define EDID_DETAILED_TIMINGS 4
>  
>  #define EDID_EXTENSION_FLAG_OFFSET  ((size_t)&((struct edid *)0)->extensions)
> -#define EDID_CHECKSUM_OFFSET  ((size_t)&((struct edid *)0)->checksum)
> +#define EDID_CHECKSUM_OFFSET	    ((size_t)&((struct edid *)0)->checksum)
> +#define EDID_VERSION_MAJOR_OFFSET   ((size_t)&((struct edid *)0)->version)
> +#define EDID_VERSION_MINOR_OFFSET   ((size_t)&((struct edid *)0)->revision)

Better to use offsetof().

Takashi