From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH v2] ARM: tegra: ventana: enable internal display Date: Fri, 16 Nov 2012 10:07:43 -0700 Message-ID: <50A672DF.1070003@wwwdotorg.org> References: <1353051891-26725-1-git-send-email-acourbot@nvidia.com> <2481172.Lt8JIisq3X@percival> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <2481172.Lt8JIisq3X@percival> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alex Courbot Cc: Mark Zhang , Thierry Reding , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-tegra@vger.kernel.org On 11/16/2012 12:51 AM, Alex Courbot wrote: > On Friday 16 November 2012 15:44:51 Alexandre Courbot wrote: >> Enable host1x and add the rgb output, providing EDID as a binary blob. > > I would really prefer to have the EDID data fetched from DDC, but all my > attempts have failed so far. I don't even see the DDC wires on the platform > design guide. Mark, are you sure the EDID data you fetched with i2cget was > actually on Ventana? I can see that the DDC lines of T2 are connected to the > corresponding lines of the HDMI interface, but nothing similar regarding > internal display. Yes, there is an EDID EEPROM on Ventana. We should certainly use that. Assuming you have CONFIG_I2C_CHARDEV=y in the kernel's .config, and the latest Ventana .dts file which enables the I2C bus mux, then the following command dumps the EDID: i2cdump -f -y 5 0x50 That should be equivalent to something like: nvidia,ddc-i2c-bus = <&lcd_ddc>; with lcd_ddc pointing at /i2cmux/i2c@1 That seems to work fine for me; how about you? For reference, the patch below, although all the whitespace is screwed up due to pasting it; I should really start using a "proper" email client...: > diff --git a/arch/arm/boot/dts/tegra20-ventana.dts b/arch/arm/boot/dts/tegra20-ventana.dts > index 9731ba9..951f432 100644 > --- a/arch/arm/boot/dts/tegra20-ventana.dts > +++ b/arch/arm/boot/dts/tegra20-ventana.dts > @@ -14,7 +14,7 @@ > dc@54200000 { > rgb { > status = "okay"; > - nvidia,edid = /incbin/("tegra20-ventana.edid"); > + nvidia,ddc-i2c-bus = <&lcd_ddc>; > backlight = <&backlight>; > }; > }; > @@ -351,7 +351,7 @@ > #size-cells = <0>; > }; > > - i2c@1 { > + lcd_ddc: i2c@1 { > reg = <1>; > #address-cells = <1>; > #size-cells = <0>;