[PATCH 03/20] mmc: mmci: Update DT documentation

Ulf Hansson ulf.hansson at linaro.org
Mon Mar 24 05:03:26 EDT 2014


On 21 March 2014 16:03, Rob Herring <robherring2 at gmail.com> wrote:
> On Fri, Mar 21, 2014 at 7:14 AM, Ulf Hansson <ulf.hansson at linaro.org> wrote:
>> Document how to configure the regulator supplies and add an example of
>> a typical mmci DT node.
>>
>> Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
>> ---
>>  Documentation/devicetree/bindings/mmc/mmci.txt |   35 ++++++++++++++++++++++--
>>  1 file changed, 33 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/mmc/mmci.txt b/Documentation/devicetree/bindings/mmc/mmci.txt
>> index 2b584ca..d167562 100644
>> --- a/Documentation/devicetree/bindings/mmc/mmci.txt
>> +++ b/Documentation/devicetree/bindings/mmc/mmci.txt
>> @@ -9,7 +9,38 @@ by mmc.txt and the properties used by the mmci driver.
>>  Required properties:
>>  - compatible             : contains "arm,pl18x", "arm,primecell".
>>  - arm,primecell-periphid : contains the PrimeCell Peripheral ID.
>
> This should not be required. This is only for if the peripheral ID is
> wrong in the h/w.

You are right, I will move it to the optional section and add better
comment for it.

>
>> +- vmmc-supply            : phandle to the regulator device tree node.
>
> You cannot add new required properties as that breaks the ABI. The
> exception is if you *know* it is okay to break all users of this
> binding.

It's okay, this is already supported by the users.

>
>>  Optional properties:
>> -- mmc-cap-mmc-highspeed  : indicates whether MMC is high speed capable
>> -- mmc-cap-sd-highspeed   : indicates whether SD is high speed capable
>> +- mmc-cap-mmc-highspeed  : indicates whether MMC is high speed capable.
>> +- mmc-cap-sd-highspeed   : indicates whether SD is high speed capable.
>> +- vqmmc-supply           : phandle to the regulator device tree node.
>
> Is this a standard property? If not, explain what vmmc and vgmmc are
> for and what the difference is.

Currently both vqmmc and vmmc are handled through an API provided by
the mmc core. It's up to each mmc host driver to use it. So, yes -
this is a standard mmc binding, but it depends on the host if it's
supported.

I suppose I could add it as an optional binding for the generic mmc
bindings and then keep them here for mmci as well?

>
>> +
>> +Example:
>> +
>> +sdi0_per1 at 80126000 {
>> +       compatible = "arm,pl18x", "arm,primecell";
>> +       arm,primecell-periphid = <0x10480180>;
>
> Drop this from the example.
>
>> +       reg = <0x80126000 0x1000>;
>> +       interrupts = <0 60 IRQ_TYPE_LEVEL_HIGH>;
>> +
>> +       dmas = <&dma 29 0 0x2>, /* Logical - DevToMem */
>> +              <&dma 29 0 0x0>; /* Logical - MemToDev */
>> +       dma-names = "rx", "tx";
>> +
>> +       clocks = <&prcc_kclk 1 5>, <&prcc_pclk 1 5>;
>> +       clock-names = "sdi", "apb_pclk";
>> +
>> +       max-frequency = <100000000>;
>> +       bus-width = <4>;
>> +       mmc-cap-sd-highspeed;
>> +       mmc-cap-mmc-highspeed;
>> +       cd-gpios  = <&gpio2 31 0x4>; // 95
>> +
>> +       vmmc-supply = <&ab8500_ldo_aux3_reg>;
>> +       vqmmc-supply = <&vmmci>;
>> +
>> +       pinctrl-names = "default", "sleep";
>> +       pinctrl-0 = <&sdi0_default_mode>;
>> +       pinctrl-1 = <&sdi0_sleep_mode>;
>> +};
>> --
>> 1.7.9.5
>>
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Thanks for reviewing!

Kind regards
Ulf Hansson



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