Hi Marcel,
On 02/05/2016 06:12 PM, Marcel Ziswiler wrote:
From: Petr Štetiar <yn...@true.cz>
Signed-off-by: Marcel Ziswiler <marcel.ziswi...@toradex.com>
Signed-off-by: Petr Štetiar <yn...@true.cz>
Reviewed-by: Stefan Agner <ste...@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because the change is in mainline now below is kind of out of date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.
--
With best wishes,
Vladimir