[PATCH v2] clk: exynos4: Fix wrong clock for Exynos4x12 ADC

Krzysztof Kozlowski k.kozlowski at samsung.com
Sun Jul 5 21:03:32 PDT 2015

2015-06-12 14:46 GMT+09:00 Javier Martinez Canillas <javier at dowhile0.org>:
> Hello Krzysztof,
> On Fri, Jun 12, 2015 at 3:53 AM, Krzysztof Kozlowski
> <k.kozlowski at samsung.com> wrote:
>> The TSADC gate clock was used in Exynos4x12 DTSI for exynos-adc driver.
>> However TSADC is present only on Exynos4210 so on Trats2 board (with
>> Exynos4412 SoC) the exynos-adc driver could not be probed:
>>    ERROR: could not get clock /adc at 126C0000:adc(0)
>>    exynos-adc 126c0000.adc: failed getting clock, err = -2
>>    exynos-adc: probe of 126c0000.adc failed with error -2
>> Instead on Exynos4x12 SoCs the main clock used by Analog to Digital
>> Converter is located in different register and it is named in datasheet
>> as PCLK_ADC. Regardless of the name the purpose of this PCLK_ADC clock
>> is the same as purpose of TSADC from Exynos4210.
>> The patch adds gate clock for Exynos4x12 using the proper register so
>> backward compatibility is preserved. This fixes the probe of exynos-adc
>> driver on Exynos4x12 boards and allows accessing sensors connected to it
>> on Trats2 board (ntc,ncp15wb473 AP and battery thermistors).
>> Signed-off-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
>> Cc: <stable at vger.kernel.org>
>> Fixes: c63c57433003 ("ARM: dts: Add ADC's dt data to read raw data for exynos4x12")
>> Link: https://lkml.org/lkml/2015/6/11/85
>> ---
>> Changes since v1:
>> 1. After discussion on LKML this solution was chosen because it smaller,
>>    simpler, self-contained (one patch to fix issue) and maintains backward
>>    compatibility. Thanks to Javier Martinez Canillas and Tomasz Figa for
>>    valuable comments.
>> 2. Dropped patch 2/2 because now it is not needed. The clock id "TSADC"
>>    will be used on all Exynos4 boards.
>> 3. Added CC-stable.
>> ---
>>  drivers/clk/samsung/clk-exynos4.c | 2 ++
>>  1 file changed, 2 insertions(+)
> Patch looks good to me.
> Reviewed-by: Javier Martinez Canillas <javier.martinez at collabora.co.uk>

Hi Tomasz and Sylwester,

Any comments on this version of patch?
Tomasz, you gave me comments on previous version. Are their satisfied?

Best regards,

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