Re: [PATCH v4] gpio: mockup: Allow probing from device tree

[Bartosz Golaszewski]

On Thu, Oct 29, 2020 at 9:17 AM Vincent Whitchurch
<vincent.whitchurch@xxxxxxxx> wrote:
>
> Allow the mockup driver to be probed via the device tree without any
> module parameters, allowing it to be used to configure and test higher
> level drivers like the leds-gpio driver and corresponding userspace
> before actual hardware is available.
>
> Signed-off-by: Vincent Whitchurch <vincent.whitchurch@xxxxxxxx>
> ---
>
> Notes:
>     v4:
>     - Remove of_match_ptr() to fix unused variable warning with W=1
>     - Include linux/mod_devicetable.h instead of linux/of.h
>
>     v3:
>     - Keep includes sorted alphabetically
>     - Drop CONFIG_OF ifdefs
>
>     v2:
>     - Remove most of the added code, since the latest driver doesn't need it.
>     - Drop DT binding document, since Rob Herring was OK with not documenting this:
>       https://lore.kernel.org/linux-devicetree/5baa1ae6.1c69fb81.847f2.3ab1@xxxxxxxxxxxxx/
>
> Range-diff against v3:
> 1:  1e9b8f36676d ! 1:  4e8fdcfe1a47 gpio: mockup: Allow probing from device tree
>     @@ Commit message
>
>
>       ## Notes ##
>     +    v4:
>     +    - Remove of_match_ptr() to fix unused variable warning with W=1
>     +    - Include linux/mod_devicetable.h instead of linux/of.h
>     +
>          v3:
>          - Keep includes sorted alphabetically
>          - Drop CONFIG_OF ifdefs
>     @@ Notes
>
>       ## drivers/gpio/gpio-mockup.c ##
>      @@
>     + #include <linux/irq.h>
>       #include <linux/irq_sim.h>
>       #include <linux/irqdomain.h>
>     ++#include <linux/mod_devicetable.h>
>       #include <linux/module.h>
>     -+#include <linux/of.h>
>       #include <linux/platform_device.h>
>       #include <linux/property.h>
>     - #include <linux/slab.h>
>      @@ drivers/gpio/gpio-mockup.c: static int gpio_mockup_probe(struct platform_device *pdev)
>         return 0;
>       }
>     @@ drivers/gpio/gpio-mockup.c: static int gpio_mockup_probe(struct platform_device
>       static struct platform_driver gpio_mockup_driver = {
>         .driver = {
>                 .name = "gpio-mockup",
>     -+          .of_match_table = of_match_ptr(gpio_mockup_of_match),
>     ++          .of_match_table = gpio_mockup_of_match,
>         },
>         .probe = gpio_mockup_probe,
>       };
>

Please don't do the above.

>  drivers/gpio/gpio-mockup.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
> index 67ed4f238d43..28b757d34046 100644
> --- a/drivers/gpio/gpio-mockup.c
> +++ b/drivers/gpio/gpio-mockup.c
> @@ -15,6 +15,7 @@
>  #include <linux/irq.h>
>  #include <linux/irq_sim.h>
>  #include <linux/irqdomain.h>
> +#include <linux/mod_devicetable.h>
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>  #include <linux/property.h>
> @@ -460,9 +461,16 @@ static int gpio_mockup_probe(struct platform_device *pdev)
>         return 0;
>  }
>
> +static const struct of_device_id gpio_mockup_of_match[] = {
> +       { .compatible = "gpio-mockup", },
> +       {},
> +};
> +MODULE_DEVICE_TABLE(of, gpio_mockup_of_match);
> +
>  static struct platform_driver gpio_mockup_driver = {
>         .driver = {
>                 .name = "gpio-mockup",
> +               .of_match_table = gpio_mockup_of_match,
>         },
>         .probe = gpio_mockup_probe,
>  };
> @@ -556,8 +564,7 @@ static int __init gpio_mockup_init(void)
>  {
>         int i, num_chips, err;
>
> -       if ((gpio_mockup_num_ranges < 2) ||
> -           (gpio_mockup_num_ranges % 2) ||
> +       if ((gpio_mockup_num_ranges % 2) ||
>             (gpio_mockup_num_ranges > GPIO_MOCKUP_MAX_RANGES))
>                 return -EINVAL;
>
> --
> 2.28.0
>

Applied now, thanks!

Bartosz