Re: [PATCH v1 4/4] leds: no longer use unnamed gpios

[Alexandre Courbot <gnurou@gmail.com>]

On Wed, Jan 14, 2015 at 10:20 PM, Olliver Schinagl <oliver@schinagl.nl> wrote:
>
> On 14-01-15 13:45, Linus Walleij wrote:
>>
>> On Thu, Jan 8, 2015 at 11:12 PM, Dmitry Torokhov
>> <dmitry.torokhov@gmail.com> wrote:
>>>
>>> On Thu, Jan 08, 2015 at 08:40:20AM -0600, Rob Herring wrote:
>>>>
>>>> On Thu, Jan 8, 2015 at 2:45 AM, Olliver Schinagl <oliver@schinagl.nl>
>>>> wrote:
>>>>>>>
>>>>>>> --- a/drivers/leds/leds-gpio.c
>>>>>>> +++ b/drivers/leds/leds-gpio.c
>>>>>>> @@ -184,7 +184,7 @@ static struct gpio_leds_priv
>>>>>>> *gpio_leds_create(struct
>>>>>>> platform_device *pdev)
>>>>>>>                  struct gpio_led led = {};
>>>>>>>                  const char *state = NULL;
>>>>>>>    -             led.gpiod = devm_get_gpiod_from_child(dev, NULL,
>>>>>>> child);
>>>>>>> +               led.gpiod = devm_get_gpiod_from_child(dev, "led",
>>>>>>> child);
>>>>>>
>>>>>> Would not this break existing boards using old bindings? You need to
>>>>>> handle both cases: if you can't located "led-gpios" then you will have
>>>>>> to
>>>>>> try just "gpios".
>>>>>
>>>>> Very true. I was rather even hoping we could update all bindings, I
>>>>> don't
>>>>> mind going through the available dts files to fix them ... But need to
>>>>> know
>>>>> that that's the proper way to go before doing the work ;)
>>>>
>>>> That will not work. You cannot make changes that require a new dtb
>>>> with a new kernel. This would also break for the other way around
>>>> (i.e. a new dtb and old kernel).
>>>>
>>>> You would have to search for both led-gpios and gpios. I'm not sure if
>>>> we can do that generically for all GPIOs. If you had a node with both
>>>> "blah-gpios" and "gpios", it would break. I would hope there are no
>>>> such cases like that. We also now have to consider how ACPI identifies
>>>> GPIOs and whether this makes sense.
>>>
>>> I think only the driver itself can know about such "legacy" mappings and
>>> make a decision.
>>
>> Yeah leds-gpio.c will need to be patched to check for "led-gpios" first
>> and then fall back to "gpios" if not found.
>
> yeah I've done the work, just need to double check it and resend a v2.
>
> Linus, I assume you want the already applied patches omitted from v2?

Yes, please base new revisions on Linus' devel branch, omitting any
patches that he has already accepted.