From: Chris Wilson <chris@chris-wilson.co.uk>
To: Keith Packard <keithp@keithp.com>,
Jesse Barnes <jbarnes@virtuousgeek.org>,
Dave Airlie <airlied@gmail.com>
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH] drm/i915: no LVDS on Intel SandyBridge SDVs
Date: Tue, 21 Dec 2010 19:55:15 +0000 [thread overview]
Message-ID: <5b55a1$j1b72o@fmsmga002.fm.intel.com> (raw)
In-Reply-To: <yun39prq9gk.fsf@aiko.keithp.com>
On Tue, 21 Dec 2010 10:14:51 -0800, Keith Packard <keithp@keithp.com> wrote:
> On Tue, 21 Dec 2010 11:36:44 +0000, Chris Wilson <chris@chris-wilson.co.uk> wrote:
>
> > I think once upon a time I found a reliable method in the docs:
> > intel_lvds_ddc_probe(). However that only seemed to work over GMBUS...
>
> That probably depends on the panel having DDC, which many don't, right?
> Maybe we can assume the SDV panels do?
The test we do is simply whether the LVDS i2c pins are addressable. That
requires differentiating between an IO error and a NAK, which at present
is only possible using GMBUS. The reference to this method I found in the
BIOS writers' guide, but of course that doesn't actually explain how it
works (especially the significance of address 0xa0).
-Chris
--
Chris Wilson, Intel Open Source Technology Centre
next prev parent reply other threads:[~2010-12-21 19:55 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-12-20 20:05 [PATCH] drm/i915: no LVDS on Intel SandyBridge SDVs Jesse Barnes
2010-12-20 20:46 ` Chris Wilson
2010-12-21 2:43 ` Dave Airlie
2010-12-21 2:53 ` Jesse Barnes
2010-12-21 11:36 ` Chris Wilson
2010-12-21 18:14 ` Keith Packard
2010-12-21 19:55 ` Chris Wilson [this message]
2010-12-21 20:12 ` Keith Packard
2010-12-22 14:47 ` Chris Wilson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='5b55a1$j1b72o@fmsmga002.fm.intel.com' \
--to=chris@chris-wilson.co.uk \
--cc=airlied@gmail.com \
--cc=intel-gfx@lists.freedesktop.org \
--cc=jbarnes@virtuousgeek.org \
--cc=keithp@keithp.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.