[PATCH V2 1/2] leds: gpio: Add kernel log if devm_fwnode_gpiod_get fails

[Stefan Wahren]

Hi Andy,

[add Linus and Bartosz]

Am 20.11.23 um 12:47 schrieb Andy Shevchenko:
> On Sat, Nov 18, 2023 at 01:42:51PM +0100, Stefan Wahren wrote:
>> In case leds-gpio fails to get the GPIO from the DT (e.g. the GPIO is
>> already requested) the driver doesn't provide any helpful error log:
>>
>>      leds-gpio: probe of leds failed with error -16
>>
>> So add a new error log in case devm_fwnode_gpiod_get() fails.
> ...
>
>>   		led.gpiod = devm_fwnode_gpiod_get(dev, child, NULL, GPIOD_ASIS,
>>   						  NULL);
>>   		if (IS_ERR(led.gpiod)) {
>> +			dev_err_probe(dev, PTR_ERR(led.gpiod), "Failed to get gpio '%pfw'\n",
>> +				      child);
>>   			fwnode_handle_put(child);
>>   			return ERR_CAST(led.gpiod);
>>   		}
> Thinking more about it. GPIO library already issues bunch of messages.
>
> 	"using DT ... for ... GPIO lookup"
> 	"using lookup tables for GPIO lookup"
> 	"No GPIO consumer ... found"
are these errors or debug messages?

I cannot remember that i saw any of them on info level in my case of an
already allocated pin (see patch 2).

I'm open to place the log within gpiolib, if this a better place.

Best regards
>
> Isn't it enough?
>