[PATCH 3/6] arm: dts: k3-am642: Sync main_i2c0 with kernel

[Nishanth Menon]

On 17:13-20230706, Roger Quadros wrote:
> Hi Nishanth,
> 
> On 06/07/2023 15:38, Nishanth Menon wrote:
> > On 21:10-20230704, Roger Quadros wrote:
> >> main_i2c0 and pinmux should be in k3-am642-evm.dts.
> >> Also add the I2C EEPROM.
> >>
> >> Signed-off-by: Roger Quadros <rogerq at kernel.org>
> >> ---
> >>  arch/arm/dts/k3-am642-evm-u-boot.dtsi | 11 -----------
> >>  arch/arm/dts/k3-am642-evm.dts         | 20 ++++++++++++++++++++
> >>  2 files changed, 20 insertions(+), 11 deletions(-)
> >>
> >> diff --git a/arch/arm/dts/k3-am642-evm-u-boot.dtsi b/arch/arm/dts/k3-am642-evm-u-boot.dtsi
> >> index 64857b0909..80c04d0117 100644
> >> --- a/arch/arm/dts/k3-am642-evm-u-boot.dtsi
> >> +++ b/arch/arm/dts/k3-am642-evm-u-boot.dtsi
> >> @@ -34,21 +34,10 @@
> >>  
> >>  &main_pmx0 {
> >>  	bootph-pre-ram;
> >> -	main_i2c0_pins_default: main-i2c0-pins-default {
> >> -		bootph-pre-ram;
> >> -		pinctrl-single,pins = <
> >> -			AM64X_IOPAD(0x0260, PIN_INPUT_PULLUP, 0) /* (A18) I2C0_SCL */
> >> -			AM64X_IOPAD(0x0264, PIN_INPUT_PULLUP, 0) /* (B18) I2C0_SDA */
> >> -		>;
> >> -	};
> >>  };
> >>  
> >>  &main_i2c0 {
> >> -	status = "okay";
> >>  	bootph-pre-ram;
> >> -	pinctrl-names = "default";
> >> -	pinctrl-0 = <&main_i2c0_pins_default>;
> >> -	clock-frequency = <400000>;
> >>  };
> >>  
> >>  &main_uart0 {
> >> diff --git a/arch/arm/dts/k3-am642-evm.dts b/arch/arm/dts/k3-am642-evm.dts
> >> index 39feea78a0..529eb81538 100644
> >> --- a/arch/arm/dts/k3-am642-evm.dts
> >> +++ b/arch/arm/dts/k3-am642-evm.dts
> >> @@ -233,6 +233,13 @@
> >>  		>;
> >>  	};
> >>  
> >> +	main_i2c0_pins_default: main-i2c0-default-pins {
> >> +		pinctrl-single,pins = <
> >> +			AM64X_IOPAD(0x0260, PIN_INPUT_PULLUP, 0) /* (A18) I2C0_SCL */
> >> +			AM64X_IOPAD(0x0264, PIN_INPUT_PULLUP, 0) /* (B18) I2C0_SDA */
> >> +		>;
> >> +	};
> >> +
> >>  	main_i2c1_pins_default: main-i2c1-pins-default {
> >>  		pinctrl-single,pins = <
> >>  			AM64X_IOPAD(0x0268, PIN_INPUT_PULLUP, 0) /* (C18) I2C1_SCL */
> >> @@ -335,6 +342,19 @@
> >>  	status = "reserved";
> >>  };
> >>  
> >> +&main_i2c0 {
> >> +	status = "okay";
> >> +	pinctrl-names = "default";
> >> +	pinctrl-0 = <&main_i2c0_pins_default>;
> >> +	clock-frequency = <400000>;
> >> +
> >> +	eeprom at 50 {
> >> +		/* AT24CM01 */
> >> +		compatible = "atmel,24c1024";
> >> +		reg = <0x50>;
> >> +	};
> >> +};
> >> +
> >>  &main_i2c1 {
> >>  	status = "okay";
> >>  	pinctrl-names = "default";
> >> -- 
> >> 2.34.1
> >>
> > 
> > We should be getting this change again as part of sync back from kernel.
> > 
> > 
> Got it.
> 
> Adding the EEPROM node causes I2C timeout error prints like below.
> Any clue why that would be the case?
> 
> Timed out in wait_for_event: status=0000
> Check if pads/pull-ups of bus are properly configured
> EEPROM not available at 0x50, trying to read at 0x51
> Timed out in wait_for_event: status=0000
> Check if pads/pull-ups of bus are properly configured
> Reading on-board EEPROM at 0x51 failed -121

https://lore.kernel.org/all/20230414073328.381336-7-nm@ti.com/
https://gist.github.com/nmenon/6b09f55251225d3f3cce076c32a33bba#file-am64-evm-L658

Seems to work for me in kernel - u-boot we will need to debug a bit. it
has been a massive pain in the backend to deal with the mix of
mis-behaving eeproms so far (whack-a-mole).. :(


-- 
Regards,
Nishanth Menon
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