linux-kernel - Re: [PATCH] arm: dts: fix rk3066a based boards vdd

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <66bc44e2-2549-c6d1-150c-5ddadf538f06@rock-chips.com>
Date:   Mon, 19 Sep 2016 17:38:10 +0800
From:   Andy Yan <andy.yan@...k-chips.com>
To:     Boris Brezillon <boris.brezillon@...e-electrons.com>
Cc:     heiko@...ech.de, linux-kernel@...r.kernel.org,
        linux-rockchip@...ts.infradead.org,
        linux-arm-kernel@...ts.infradead.org
Subject: Re: [PATCH] arm: dts: fix rk3066a based boards vdd_log voltage
 initialization



On 2016年09月19日 17:25, Boris Brezillon wrote:
> On Mon, 19 Sep 2016 16:44:56 +0800
> Andy Yan <andy.yan@...k-chips.com> wrote:
>
>> The current rk3066a based boards(Rayeager, Bqcurie2, Marsboard) use
>> pwm modulate vdd_logic voltage, but the pwm is default disabled and
>> the pwm pin acts as a gpio before pwm regulator probed, so the pwm
>> regulator driver will get a zero dutycycle at probe time, so change
>> the initial dutycycle to zero to match pwm_regulator_init_state check.
>>
>> Signed-off-by: Andy Yan <andy.yan@...k-chips.com>
>>
>> ---
>>
>>   arch/arm/boot/dts/rk3066a-bqcurie2.dts  | 2 +-
>>   arch/arm/boot/dts/rk3066a-marsboard.dts | 2 +-
>>   arch/arm/boot/dts/rk3066a-rayeager.dts  | 2 +-
>>   3 files changed, 3 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm/boot/dts/rk3066a-bqcurie2.dts b/arch/arm/boot/dts/rk3066a-bqcurie2.dts
>> index bc674ee..618450d 100644
>> --- a/arch/arm/boot/dts/rk3066a-bqcurie2.dts
>> +++ b/arch/arm/boot/dts/rk3066a-bqcurie2.dts
>> @@ -61,7 +61,7 @@
>>   		regulator-min-microvolt = <1200000>;
>>   		regulator-max-microvolt = <1200000>;
>>   		regulator-always-on;
>> -		voltage-table = <1000000 100>,
>> +		voltage-table = <1000000 0>,
>>   				<1200000 42>;
> So, it seems you are reversing the PWM polarity here. Are you sure you
> shouldn't change the 2nd entry of this table (<1200000 58>)?


     no, 42% duty cycle give a stable 1.2v vdd_logic voltage on my 
board. As i explained in the commit, the pwm was default at a disabled 
state before regulator_register success at pwm_regulator probe, so 
pwm_regulator_init_state  function will get  a zero dutycycle from 
pwm_get_relative_dutycycle. I have to change the dutycycle of  fist 
table to zero to match the following check, other wise the function will 
return defualt value(-EINVAL), then the pwm regulator register failed.
>
>>   		status = "okay";
>>   	};
>> diff --git a/arch/arm/boot/dts/rk3066a-marsboard.dts b/arch/arm/boot/dts/rk3066a-marsboard.dts
>> index a2b763e..ddc680b 100644
>> --- a/arch/arm/boot/dts/rk3066a-marsboard.dts
>> +++ b/arch/arm/boot/dts/rk3066a-marsboard.dts
>> @@ -59,7 +59,7 @@
>>   		regulator-min-microvolt = <1200000>;
>>   		regulator-max-microvolt = <1200000>;
>>   		regulator-always-on;
>> -		voltage-table = <1000000 100>,
>> +		voltage-table = <1000000 0>,
>>   				<1200000 42>;
>>   		status = "okay";
>>   	};
>> diff --git a/arch/arm/boot/dts/rk3066a-rayeager.dts b/arch/arm/boot/dts/rk3066a-rayeager.dts
>> index 2536b3a..30aee99 100644
>> --- a/arch/arm/boot/dts/rk3066a-rayeager.dts
>> +++ b/arch/arm/boot/dts/rk3066a-rayeager.dts
>> @@ -84,7 +84,7 @@
>>   		regulator-min-microvolt = <1200000>;
>>   		regulator-max-microvolt = <1200000>;
>>   		regulator-always-on;
>> -		voltage-table = <1000000 100>,
>> +		voltage-table = <1000000 0>,
>>   				<1200000 42>;
>>   		status = "okay";
>>   	};
>
>
>