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Date:   Thu, 25 Aug 2022 10:04:36 +0200
From:   Henning Schild <henning.schild@siemens.com>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Pavel Machek <pavel@ucw.cz>, Lee Jones <lee@kernel.org>,
        Linux LED Subsystem <linux-leds@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] leds: simatic-ipc-leds-gpio: make sure we have the
 GPIO providing driver
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Am Wed, 24 Aug 2022 18:53:49 +0300
schrieb Andy Shevchenko <andy.shevchenko@gmail.com>:

> On Wed, Aug 24, 2022 at 4:27 PM Henning Schild
> <henning.schild@siemens.com> wrote:
> >
> > If we register a "leds-gpio" platform device for GPIO pins that do
> > not exist we get a -EPROBE_DEFER and the probe will be tried again
> > later. If there is not driver to provide that pin we will poll
> > forever and also  
> 
> not --> no
> 
> > create a lot of log messages.
> >
> > So check if that GPIO driver is configured, if so it will come up
> > eventually. If not we exit our probe function early and do not even
> >  
> 
> not, we
> 
> > bother registering the "leds-gpio". This method was chosen over
> > "Kconfig depends" since this way we can add support for more
> > devices and GPIO backends more easily without "depends"ing on all
> > GPIO backends.  
> 
> "depends":ing
> 
> The code is fine from my perspective,
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> thanks!

Thank you! Typos fixed and tag added in v3.

Henning

> 
> > Fixes: a6c80bec3c93 ("leds: simatic-ipc-leds-gpio: Add GPIO version
> > of Siemens driver") Signed-off-by: Henning Schild
> > <henning.schild@siemens.com> ---
> >  drivers/leds/simple/simatic-ipc-leds-gpio.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/leds/simple/simatic-ipc-leds-gpio.c
> > b/drivers/leds/simple/simatic-ipc-leds-gpio.c index
> > 4c9e663a90ba..0c96ba98e338 100644 ---
> > a/drivers/leds/simple/simatic-ipc-leds-gpio.c +++
> > b/drivers/leds/simple/simatic-ipc-leds-gpio.c @@ -57,6 +57,8 @@
> > static int simatic_ipc_leds_gpio_probe(struct platform_device
> > *pdev) struct gpio_desc *gpiod; int err;
> >
> > +       if (!IS_ENABLED(CONFIG_PINCTRL_BROXTON))
> > +               return -ENODEV;
> >         gpiod_add_lookup_table(&simatic_ipc_led_gpio_table);
> >         simatic_leds_pdev = platform_device_register_resndata(NULL,
> >                 "leds-gpio", PLATFORM_DEVID_NONE, NULL, 0,
> > --
> > 2.35.1
> >  
> 
>