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From: Jani Nikula <jani.nikula@linux.intel.com>
To: lester magtagad <lester.magtagad@gmail.com>,
	dri-devel@lists.freedesktop.org
Cc: John Sledge <john_sledget@yahoo.com>
Subject: Re: libdrm to read/write drm_dpcd helper functions.
Date: Fri, 25 May 2018 11:39:24 +0300	[thread overview]
Message-ID: <87h8mw2koz.fsf@intel.com> (raw)
In-Reply-To: <CAG_9rwN766RWTaJ6LCiZeXQZZC5FBEr6HadkRi0vRMceWjQdyQ@mail.gmail.com>

On Fri, 25 May 2018, lester magtagad <lester.magtagad@gmail.com> wrote:
> Hello everyone,
>
> I am new to DRM and linux, I started reading developers guide and research
> on my own.
>
> I don't know where to start on how to communicate the DP helper functions
> (drm_dp_dpcd_read,  drm_dp_dpcd_readb,  drm_dp_dpcd_write,
> drm_dp_dpcd_writeb),
> what will I include(#include<sample.h>) in my main program. I already have
> drm in my setup(kernel version:4.4.21-69), I also have libdrm-2.4.92 API  ,
> the problem is I don't really have an idea on how use it.
>
> My main objective is I want to read and write brightness/backlight level on
> DP connections.
>
> Is it possible to use only the libdrm api to import DP helper functions?if
> yes how?
>
> Maybe someone can help/guide me on this?

Where does the sudden interest with DPCD access from userspace come
from? See the thread [1]. My replies there should cover this.

I'm starting to wonder if this is an XY problem...

BR,
Jani.


[1] http://mid.mail-archive.com/471791572.2287221.1526561265798@mail.yahoo.com


-- 
Jani Nikula, Intel Open Source Graphics Center
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      reply	other threads:[~2018-05-25  8:39 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-25  3:37 libdrm to read/write drm_dpcd helper functions lester magtagad
2018-05-25  8:39 ` Jani Nikula [this message]

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