Re: [PATCH 1/2] arm64: tegra: Add pinmux for PWM-based DFLL support on Shield platform

[Joseph Lo <josephl@nvidia.com>]

On 3/22/19 5:52 PM, Thierry Reding wrote:
> On Fri, Mar 22, 2019 at 03:11:10PM +0800, Joseph Lo wrote:
>> Add pinmux for PWM-based DFLL support on Shield platform.
>>
>> Signed-off-by: Joseph Lo <josephl@nvidia.com>
>> ---
>>   arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi | 14 ++++++++++++++
>>   1 file changed, 14 insertions(+)
> 
> There's been some discussion recently about moving away from programming
> pinmux in the kernel because it isn't always safe to do that. The idea
> is that early boot firmware (typically cboot) will already have set up
> the pinmux, so there's no need to do it again in the kernel.
> 
> These look like you're going to change this pin to/from tristate at
> runtime, so perhaps that's the kind of thing that we're okay with?
> 
> Adding Stephen for visibility.

Gentle ping.

Thanks,
Joseph

> 
> Thierry
> 
>> diff --git a/arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi b/arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi
>> index 88a4b9333d84..c668f16c8574 100644
>> --- a/arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi
>> +++ b/arch/arm64/boot/dts/nvidia/tegra210-p2894.dtsi
>> @@ -1318,6 +1318,20 @@
>>   				nvidia,open-drain = <TEGRA_PIN_DISABLE>;
>>   			};
>>   		};
>> +
>> +		dvfs_pwm_active_state: dvfs_pwm_active {
>> +			dvfs_pwm_pbb1 {
>> +				nvidia,pins = "dvfs_pwm_pbb1";
>> +				nvidia,tristate = <TEGRA_PIN_DISABLE>;
>> +			};
>> +		};
>> +
>> +		dvfs_pwm_inactive_state: dvfs_pwm_inactive {
>> +			dvfs_pwm_pbb1 {
>> +				nvidia,pins = "dvfs_pwm_pbb1";
>> +				nvidia,tristate = <TEGRA_PIN_ENABLE>;
>> +			};
>> +		};
>>   	};
>>   
>>   	serial@70006000 {
>> -- 
>> 2.21.0
>>