Re: [PATCH v2 1/3] ARM: dts: imx6qdl-apalis: Do not rely on DDC I2C bus bitbang for HDMI

From: Shawn Guo
Date: Fri Oct 21 2016 - 23:27:06 EST


On Mon, Sep 19, 2016 at 10:41:51AM +0530, Sanchayan Maity wrote:
> Remove the use of DDC I2C bus bitbang to support reading of EDID
> and rely on support from internal HDMI I2C master controller instead.
> As a result remove the device tree property ddc-i2c-bus.
>
> Signed-off-by: Sanchayan Maity <maitysanchayan@xxxxxxxxx>

I think that the dw-hdmi i2c support [1] is a prerequisite of this
patch. I do not see it lands on v4.9-rc1. Or am I missing something?

Shawn

[1] https://patchwork.kernel.org/patch/9296883/

> ---
> Changes since v1:
>
> Change the ranking in i2c aliases
>
> v1: https://lkml.org/lkml/2016/9/14/55
> ---
> arch/arm/boot/dts/imx6q-apalis-ixora.dts | 12 +++---------
> arch/arm/boot/dts/imx6qdl-apalis.dtsi | 25 +++++++++----------------
> 2 files changed, 12 insertions(+), 25 deletions(-)
>
> diff --git a/arch/arm/boot/dts/imx6q-apalis-ixora.dts b/arch/arm/boot/dts/imx6q-apalis-ixora.dts
> index 207b85b..82b81e0 100644
> --- a/arch/arm/boot/dts/imx6q-apalis-ixora.dts
> +++ b/arch/arm/boot/dts/imx6q-apalis-ixora.dts
> @@ -55,10 +55,9 @@
> "fsl,imx6q";
>
> aliases {
> - i2c0 = &i2cddc;
> - i2c1 = &i2c1;
> - i2c2 = &i2c2;
> - i2c3 = &i2c3;
> + i2c0 = &i2c1;
> + i2c1 = &i2c2;
> + i2c2 = &i2c3;
> };
>
> aliases {
> @@ -186,11 +185,6 @@
> };
>
> &hdmi {
> - ddc-i2c-bus = <&i2cddc>;
> - status = "okay";
> -};
> -
> -&i2cddc {
> status = "okay";
> };
>
> diff --git a/arch/arm/boot/dts/imx6qdl-apalis.dtsi b/arch/arm/boot/dts/imx6qdl-apalis.dtsi
> index 99e323b..8c67dd8 100644
> --- a/arch/arm/boot/dts/imx6qdl-apalis.dtsi
> +++ b/arch/arm/boot/dts/imx6qdl-apalis.dtsi
> @@ -53,18 +53,6 @@
> status = "disabled";
> };
>
> - /* 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";
> - };
> -
> reg_1p8v: regulator-1p8v {
> compatible = "regulator-fixed";
> regulator-name = "1P8V";
> @@ -209,6 +197,12 @@
> };
> };
>
> +&hdmi {
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_hdmi_ddc>;
> + status = "disabled";
> +};
> +
> /*
> * GEN1_I2C: I2C1_SDA/SCL on MXM3 209/211 (e.g. RTC on carrier
> * board)
> @@ -633,11 +627,10 @@
> >;
> };
>
> - pinctrl_i2c_ddc: gpioi2cddcgrp {
> + pinctrl_hdmi_ddc: hdmiddcgrp {
> fsl,pins = <
> - /* DDC bitbang */
> - MX6QDL_PAD_EIM_EB2__GPIO2_IO30 0x1b0b0
> - MX6QDL_PAD_EIM_D16__GPIO3_IO16 0x1b0b0
> + MX6QDL_PAD_EIM_EB2__HDMI_TX_DDC_SCL 0x4001b8b1
> + MX6QDL_PAD_EIM_D16__HDMI_TX_DDC_SDA 0x4001b8b1
> >;
> };
>
> --
> 2.9.3
>