[PATCH] ARM: dts: am437x-gp-evm: Add vtt_fixed regulator

Dave Gerlach d-gerlach at ti.com
Tue Apr 22 12:53:14 PDT 2014


On 04/22/2014 01:58 PM, Nishanth Menon wrote:
> On 04/22/2014 01:52 PM, Dave Gerlach wrote:
>> The VTT regulator for DDR3 termination on the am437x-gp-evm is
>> controlled by a gpio. It is configured by the bootloader so here we
>> define an always-on, fixed voltage regulator to hold the gpio.
>>
>> Signed-off-by: Dave Gerlach <d-gerlach at ti.com>
>> ---
>>   arch/arm/boot/dts/am437x-gp-evm.dts | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/arch/arm/boot/dts/am437x-gp-evm.dts b/arch/arm/boot/dts/am437x-gp-evm.dts
>> index a055f7f..e68d12c 100644
>> --- a/arch/arm/boot/dts/am437x-gp-evm.dts
>> +++ b/arch/arm/boot/dts/am437x-gp-evm.dts
>> @@ -27,6 +27,17 @@
>>   		enable-active-high;
>>   	};
>>
>> +	vtt_fixed: fixedregulator-vtt {
>
> Would you like to consider any explicit pinctrl here?

Yes, it's a good idea for me to add that in for next version.

>
>> +		compatible = "regulator-fixed";
>> +		regulator-name = "vtt_fixed";
>> +		regulator-min-microvolt = <3300000>;
>> +		regulator-max-microvolt = <3300000>;
>> +		regulator-always-on;
>> +		regulator-boot-on;
>> +		enable-active-high;
>> +		gpio = <&gpio5 7 GPIO_ACTIVE_HIGH>;
>> +	};
>> +
>>   	backlight {
>>   		compatible = "pwm-backlight";
>>   		pwms = <&ecap0 0 50000 PWM_POLARITY_INVERTED>;
>>
>
> Do we still need https://patchwork.kernel.org/patch/3871201/ (prevent
> hwmod from resetting GPIO5) ?
>

Yes, without preventing the reset boot still hangs.





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