Hi Rob,
On 2018-05-31 10:45 PM, Rob Herring wrote:
> On Wed, May 30, 2018 at 10:27 PM, <djw at t-chip.com.cn> wrote:
>> From: Levin Du <djw at t-chip.com.cn>
>>
>> In Rockchip RK3328, the output only GPIO_MUTE pin, originally for codec
>> mute control, can also be used for general purpose. It is manipulated by
>> the GRF_SOC_CON10 register.
>>
>> Signed-off-by: Levin Du <djw at t-chip.com.cn>
>>
>> ---
>>
>> Changes in v3:
>> - Change from general gpio-syscon to specific rk3328-gpio-mute
>>
>> Changes in v2:
>> - Rename gpio_syscon10 to gpio_mute in doc
>>
>> Changes in v1:
>> - Refactured for general gpio-syscon usage for Rockchip SoCs.
>> - Add doc rockchip,gpio-syscon.txt
>>
>> .../bindings/gpio/rockchip,rk3328-gpio-mute.txt | 28 +++++++++++++++++++
>> drivers/gpio/gpio-syscon.c | 31 ++++++++++++++++++++++
>> 2 files changed, 59 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/gpio/rockchip,rk3328-gpio-mute.txt
>>
>> diff --git a/Documentation/devicetree/bindings/gpio/rockchip,rk3328-gpio-mute.txt b/Documentation/devicetree/bindings/gpio/rockchip,rk3328-gpio-mute.txt
>> new file mode 100644
>> index 0000000..10bc632
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/gpio/rockchip,rk3328-gpio-mute.txt
>> @@ -0,0 +1,28 @@
>> +Rockchip RK3328 GPIO controller dedicated for the GPIO_MUTE pin.
>> +
>> +In Rockchip RK3328, the output only GPIO_MUTE pin, originally for codec mute
>> +control, can also be used for general purpose. It is manipulated by the
>> +GRF_SOC_CON10 register.
>> +
>> +Required properties:
>> +- compatible: Should contain "rockchip,rk3328-gpio-mute".
>> +- gpio-controller: Marks the device node as a gpio controller.
>> +- #gpio-cells: Should be 2. The first cell is the pin number and
>> + the second cell is used to specify the gpio polarity:
>> + 0 = Active high,
>> + 1 = Active low.
>> +
>> +Example:
>> +
>> + grf: syscon at ff100000 {
>> + compatible = "rockchip,rk3328-grf", "syscon", "simple-mfd";
>> +
>> + gpio_mute: gpio-mute {
> Node names should be generic:
>
> gpio {
>
> This also means you can't add another GPIO node in the future and
> you'll have to live with "rockchip,rk3328-gpio-mute" covering more
> than 1 GPIO if you do need to add more GPIOs.
As the first line describes, this GPIO controller is dedicated for the
GPIO_MUTE pin.
There's only one GPIO pin in the GRF_SOC_CON10 register. Therefore the
gpio_mute
name is proper IMHO.
>> + compatible = "rockchip,rk3328-gpio-mute";
>> + gpio-controller;
>> + #gpio-cells = <2>;
>> + };
>> + };
>> +
>> +Note: The gpio_mute node should be declared as the child of the GRF (General
>> +Register File) node. The GPIO_MUTE pin is referred to as <&gpio_mute 0>.
> This is wrong because you should have 2 cells. The phandle doesn't
> count as a cell.
>
> Rob
>
Thanks for pointing that out. So it should be:
?? The GPIO_MUTE pin is referred to as <&gpio_mute 0 POLARITY>.
Thanks,
Levin
