Re: [PATCH/RFC 1/3] dt-bindings: i2c: i2c-gpio: Add support for named gpios

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Hi Rob,

On Thu, Aug 31, 2017 at 7:55 PM, Rob Herring <robh@xxxxxxxxxx> 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 <geert+renesas@xxxxxxxxx>
>> ---
>>  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 -- geert@xxxxxxxxxxxxxx

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
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux