Re: [PATCH 3/3] mfd: sec-core: Disable buck voltage reset on watchdog falling edge

[Krzysztof Kozlowski]

On 05.10.2015 22:35, Bartlomiej Zolnierkiewicz wrote:
> 
> Hi,
> 
> On Friday, October 02, 2015 05:25:51 PM Krzysztof Kozlowski wrote:
>> The WRSTBI bit (disabled by default but enabled by bootloader), when
>> set, is responsible for resetting voltages to default values of
>> certain bucks on falling edge of Warm Reset Input pin from AP.
>>
>> However on some boards (with S2MPS13) the pin is pulled down so any
>> suspend will effectively trigger the reset of bucks supplying the power
>> to the little and big cores. In the same time when resuming, these bucks
>> must provide voltage greater or equal to voltage before suspend to match
>> the frequency chosen by cpufreq. If voltage (default value of voltage
>> after reset) is lower than one set by cpufreq before suspend, then
>> system will hang during resuming.
>>
>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski@xxxxxxxxxxx>
> 
> I tested this (with some additional Exynos5433 patches) and it works
> like expected (suspend/resume issue is fixed).
> 
> Tested-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
> 

Thanks!

> You could also add:
> 
> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
> 
> (since the issue got narrowed down and reported to you by me :).

I didn't put it because I wasn't sure who was the author of our report.
I'll wait a one more day for any comments and add it in v2/resend.

BTW, any comments on the binding itself?
Actually I had hard time choosing the name for binding because unlike
the ACOKB the WRSTBI pin is not grounded but pulled down. However it is
quite similar so I stick to the same convention:
 - samsung,s2mps11-acokb-ground
 - samsung,s2mps11-wrstbi-ground


Best regards,
Krzysztof
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/