[PATCH 08/11] Documentation: phy: Let the rockchip eMMC PHY get an exported card clock

Doug Anderson dianders at chromium.org
Mon Jun 13 16:05:40 PDT 2016


Rob,

On Fri, Jun 10, 2016 at 6:36 AM, Rob Herring <robh at kernel.org> wrote:
> On Tue, Jun 07, 2016 at 03:44:41PM -0700, Douglas Anderson wrote:
>> As of an earlier change in this series ("Documentation: mmc:
>> sdhci-of-arasan: Add ability to export card clock") the SDHCI driver
>> used on Rockchip SoCs can now expose its clock.  Let's now specify that
>> the PHY can use it.
>>
>> Letting the PHY get access to this clock means it can adjust
>> phyctrl_frqsel field appropriately.  Although the Rockchip PHY appears
>> slightly different than the reference Arasan one, you can see that the
>> Arasan datasheet [1] had it defined as:
>>   Select the frequency range of DLL operation:
>>   3b'000 => 200MHz to 170 MHz
>>   3b'001 => 170MHz to 140 MHz
>>   3b'010 => 140MHz to 110 MHz
>>   3b'011 => 110MHz to 80MHz
>>   3b'100 => 80MHz to 50 MHz
>>   3b'101 => 275Mhz to 250MHz
>>   3b'110 => 250MHz to 225MHz
>>   3b'111 => 225MHz to 200MHz
>>
>> On the Rockchip version of the PHY we have less granularity but the idea
>> is the same.
>>
>> [1]: https://arasan.com/wp-content/media/eMMC-5-1-Total-Solution_Rev-1-3.pdf
>>
>> Signed-off-by: Douglas Anderson <dianders at chromium.org>
>> ---
>>  Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
>> index 555cb0f40690..fd118b071e5e 100644
>> --- a/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
>> +++ b/Documentation/devicetree/bindings/phy/rockchip-emmc-phy.txt
>> @@ -7,6 +7,11 @@ Required properties:
>>   - reg: PHY register address offset and length in "general
>>     register files"
>>
>> +Optional clocks (see ../clock/clock-bindings.txt), specified by name:
>> + - emmcclk: The card clock exported by the SDHCI driver.  Although this is
>
> This reads like emmcclk is the property. You need to list out clocks and
> clock-names.

Thanks for the feedback.  Done.

-Doug



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