Hi Rob,
On Thu, Aug 31, 2017 at 7:55 PM, Rob Herring <[email protected]> wrote:
> On Thu, Aug 24, 2017 at 11:21:12AM +0200, Geert Uytterhoeven wrote:
>> The current i2c-gpio DT bindings use a single unnamed "gpios" property
>> to refer to the SDA and SCL signal lines by index. This is error-prone
>> for the casual DT writer and reviewer, as one has to look up the order
>> in the DT bindings.
>>
>> Fix this by amending the DT bindings to use two separate named gpios
>> properties, and deprecate the old unnamed variant.
>>
>> Signed-off-by: Geert Uytterhoeven <[email protected]>
>> ---
>> Documentation/devicetree/bindings/i2c/i2c-gpio.txt | 5 +++--
>> 1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
>> b/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
>> index 4f8ec947c6bd9cad..61033f73577dd70e 100644
>> --- a/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
>> +++ b/Documentation/devicetree/bindings/i2c/i2c-gpio.txt
>> @@ -2,8 +2,9 @@ Device-Tree bindings for i2c gpio driver
>>
>> Required properties:
>> - compatible = "i2c-gpio";
>> - - gpios: sda and scl gpio
>> -
>> + - sda-gpios: gpio used for the sda signal
>> + - scl-gpios: gpio used for the scl signal
>> + - gpios: sda and scl gpio, alternative for {sda,scl}-gpios (deprecated)
>>
>> Optional properties:
>> - i2c-gpio,sda-open-drain: sda as open drain
>
> Well, if we're going to change things, we should drop these open-drain
> properties. We have open-drain flags in gpio cells, so we don't need
> these I think.
It depends. Some GPIO controllers use #gpio-cells = 1, lacking flags.
Furthermore, the gpio-specifiers are controller-specific, and not all GPIO
controllers supporting flags follow the semi-standard flag definitions in
<dt-bindings/gpio/gpio.h>.
See Documentation/devicetree/bindings/gpio/gpio.txt.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
