On 2018-05-10 8:50 PM, Robin Murphy wrote:
> On 10/05/18 10:16, djw at t-chip.com.cn wrote:
>> From: Levin Du <djw at t-chip.com.cn>
>>
>> Adding a new gpio controller named "gpio-syscon10" to rk3328, providing
>> access to the pins defined in the syscon GRF_SOC_CON10.
>
> This is the GPIO_MUTE pin, right? The public TRM is rather vague, but
> cross-referencing against the datasheet and schematics implies that
> it's the "gpiomut_*" part of the GRF bit names which is most significant.
>
> It might be worth using a more descriptive name here, since "syscon10"
> is pretty much meaningless at the board level.
>
> Robin.
>
Previously I though other bits might be able to reference from syscon10,
other than GPIO_MUTE alone.
If it is renamed to gpio-mute, then the GPIO_MUTE pin is accessed as
`<&gpio-mute 1>`. Yet other
bits in syscon10 can also be referenced, say, `<&gpio-mute 10>`, which
is not good.
I'd like to add a `gpio,syscon-bit` property to gpio-syscon, which
overrides the properties
of bit_count,? data_bit_offset and dir_bit_offset in the driver. For
example:
??????????????? gpio_mute: gpio-mute {
??????????????????????? compatible = "rockchip,gpio-syscon";
??????????????????????? gpio-controller;
??????????????????????? #gpio-cells = <2>;
??????????????????????? gpio,syscon-dev = <0 0x0428 0>;
??????????????????????? gpio,syscon-bit = <1 1 0>;
??????????????? };
That way, the mute pin is strictly specified as <&gpio_mute 0>, and
<&gpio_mute 1> will be invalid.
I think that is neat, and consistent with the gpio_mute name.
Thanks
Levin
