On the Qualcomm RB2 platform the I2C bus connected to the LT9611UXC bridge under some circumstances can go into a state when all transfers timeout. This causes both issues with fetching of EDID and with updating of the bridge's firmware. While we are debugging the issue, switch corresponding I2C bus to use i2c-gpio driver. While using i2c-gpio no communication issues are observed.
This patch is asusmed to be a temporary fix, so it is implemented in a non-intrusive manner to simply reverting it later.
Fixes: f7b01e07e89c ("arm64: dts: qcom: qrb4210-rb2: Enable display out") Cc: stable@vger.kernel.org Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org --- arch/arm64/boot/dts/qcom/qrb4210-rb2.dts | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts b/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts index 2c39bb1b97db..5bfbd81db032 100644 --- a/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts +++ b/arch/arm64/boot/dts/qcom/qrb4210-rb2.dts @@ -60,6 +60,17 @@ hdmi_con: endpoint { }; };
+ i2c2_gpio: i2c2-gpio { + compatible = "i2c-gpio"; + + sda-gpios = <&tlmm 6 GPIO_ACTIVE_HIGH>; + scl-gpios = <&tlmm 7 GPIO_ACTIVE_HIGH>; + #address-cells = <1>; + #size-cells = <0>; + + status = "disabled"; + }; + leds { compatible = "gpio-leds";
@@ -190,7 +201,7 @@ zap-shader { }; };
-&i2c2 { +&i2c2_gpio { clock-frequency = <400000>; status = "okay";