linux-kernel - Re: [PATCH v4 3/5] drm: panel: simple: Allow specifying the delay from prepare to enable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20201129221158.GJ1162850@ravnborg.org>
Date:   Sun, 29 Nov 2020 23:11:58 +0100
From:   Sam Ravnborg <sam@...nborg.org>
To:     Douglas Anderson <dianders@...omium.org>
Cc:     Thierry Reding <thierry.reding@...il.com>, robdclark@...omium.org,
        David Airlie <airlied@...ux.ie>,
        dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        Rob Herring <robh+dt@...nel.org>
Subject: Re: [PATCH v4 3/5] drm: panel: simple: Allow specifying the delay
 from prepare to enable

Hi Douglas,

On Mon, Nov 09, 2020 at 05:00:57PM -0800, Douglas Anderson wrote:
> On the panel I'm looking at, there's an 80 ms minimum time between HPD
> being asserted by the panel and setting the backlight enable GPIO.
> While we could just add an 80 ms "enable" delay, this is not ideal.
> Link training is allowed to happen in parallel with this delay so the
> fixed 80 ms delay over-delays.
> 
> We'll support this by logging the time at the end of prepare and then
> delaying in enable if enough time hasn't passed.
> 
> Signed-off-by: Douglas Anderson <dianders@...omium.org>
Applied too.

	Sam