Re: [PATCH v5 1/2] ARM: dts: imx6: Add support for Toradex Apalis iMX6Q/D SoM

Marcel Ziswiler
2016-09-16T21:03:05Z

Hi Vladimir

On Mon, 2016-08-29 at 16:28 +0300, Vladimir Zapolskiy wrote:
> Hi Marcel,
>
> On 02/05/2016 06:12 PM, Marcel Ziswiler wrote:
> >
> > From: Petr Štetiar <ynezz@true.cz>
> >
> > Signed-off-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
> > Signed-off-by: Petr Štetiar <ynezz@true.cz>
> > Reviewed-by: Stefan Agner <stefan@agner.ch>
> > ---
> >
> because the change is in mainline now below is kind of out of date
> information, but you may find it helpful.
>
> [snip]
>
> >
> > - fixed HDMI DDC (requires GPIO-based bitbanging I2C to be enabled)
> This is not needed.
>
> [snip]
>
> >
> > + /* DDC_I2C: I2C2_SDA/SCL on MXM3 205/207 */
> > + i2cddc: i2c@0 {
> > + compatible = "i2c-gpio";
> > + pinctrl-names = "default";
> > + pinctrl-0 = <&pinctrl_i2c_ddc>;
> > + gpios = <&gpio3 16 GPIO_ACTIVE_HIGH /* sda */
> > +  &gpio2 30 GPIO_ACTIVE_HIGH /* scl */
> > + >;
> > + i2c-gpio,delay-us = <2>; /* ~100 kHz */
> > + status = "disabled";
> > + };
> > +
> This is not needed.
>
> [snip]
>
> >
> > + pinctrl_i2c_ddc: gpioi2cddcgrp {
> > + fsl,pins = <
> > + /* DDC bitbang */
> > + MX6QDL_PAD_EIM_EB2__GPIO2_IO30 0x1b0b0
> > + MX6QDL_PAD_EIM_D16__GPIO3_IO16 0x1b0b0
> > + >;
> > + };
> > +
> Practically you don't need this overcomplicated GPIO-based bitbanging
> to emulate I2C, because the DW HDMI controller has a reduced I2C
> controller on board, you may take a look at its support published
> here:
>
>     http://www.spinics.net/lists/dri-devel/msg116308.html
>
> To utilize it the pads should be set to HDMI function instead of
> I2C or GPIO.

Works nicely indeed, thanks for letting us know.

> --
> With best wishes,
> Vladimir

Best wishes to you too!

Cheers

Marcel