@@ -9,12 +9,34 @@ / {
compatible = "skov,imx8mp-skov-revb-hdmi", "fsl,imx8mp";
};
+&i2c5 {
+ pinctrl-names = "default", "gpio";
+ pinctrl-0 = <&pinctrl_i2c5>;
+ pinctrl-1 = <&pinctrl_i2c5_gpio>;
+ scl-gpios = <&gpio3 26 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ sda-gpios = <&gpio3 27 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
+ clock-frequency = <100000>;
+ status = "okay";
+};
+
&iomuxc {
pinctrl_hdmi: hdmigrp {
fsl,pins = <
- MX8MP_IOMUXC_HDMI_DDC_SCL__HDMIMIX_HDMI_SCL 0x1c3
- MX8MP_IOMUXC_HDMI_DDC_SDA__HDMIMIX_HDMI_SDA 0x1c3
MX8MP_IOMUXC_HDMI_HPD__HDMIMIX_HDMI_HPD 0x19
>;
};
+
+ pinctrl_i2c5: i2c5grp {
+ fsl,pins = <
+ MX8MP_IOMUXC_HDMI_DDC_SCL__I2C5_SCL 0x400001c2
+ MX8MP_IOMUXC_HDMI_DDC_SDA__I2C5_SDA 0x400001c2
+ >;
+ };
+
+ pinctrl_i2c5_gpio: i2c5gpiogrp {
+ fsl,pins = <
+ MX8MP_IOMUXC_HDMI_DDC_SCL__GPIO3_IO26 0x400001c2
+ MX8MP_IOMUXC_HDMI_DDC_SDA__GPIO3_IO27 0x400001c2
+ >;
+ };
};
The HDMI DDC pads can be muxed either to an i.MX I2C controller or to a limited I2C controller within the Designware HDMI bridge. So far, the pads were muxed to the HDMI bridge, but the i.MX I2C controller is the better choice: - The Designware HDMI I2C controller doesn't support multi-byte requests and the Linux driver refuses[1] transfers to/from address 0x37, but these are required for display/brightness configuration, - The driver doesn't support I2C bus recovery, but some HDMI panels used with the board can be flaky and require it. As the i.MX I2C controller and driver don't have either of these limitations, let's make use of it instead. [1]: https://lore.kernel.org/all/20190722181945.244395-1-mka@chromium.org/ Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> --- v1 -> v2: - use passive voice instead of "we" (Frank) --- .../boot/dts/freescale/imx8mp-skov-revb-hdmi.dts | 26 ++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-)