Re: [PATCH] arm/virt: place power button pin number on a define

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Aug 08, 2024 at 02:54:52PM +0200, Mauro Carvalho Chehab wrote:
> Having magic numbers inside the code is not a good idea, as it
> is error-prone. So, instead, create a macro with the number
> definition.
> 
> Link: https://lore.kernel.org/qemu-devel/CAFEAcA-PYnZ-32MRX+PgvzhnoAV80zBKMYg61j2f=oHaGfwSsg@mail.gmail.com/
> 
> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
> Suggested-by: Peter Maydell <peter.maydell@linaro.org>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Reviewed-by: Igor Mammedov <imammedo@redhat.com>

ack, but note we do things like that only if something
is repeated.

> ---
>  hw/arm/virt-acpi-build.c | 6 +++---
>  hw/arm/virt.c            | 7 ++++---
>  include/hw/arm/virt.h    | 3 +++
>  3 files changed, 10 insertions(+), 6 deletions(-)
> 
> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
> index e10cad86dd73..f76fb117adff 100644
> --- a/hw/arm/virt-acpi-build.c
> +++ b/hw/arm/virt-acpi-build.c
> @@ -154,10 +154,10 @@ static void acpi_dsdt_add_gpio(Aml *scope, const MemMapEntry *gpio_memmap,
>      aml_append(dev, aml_name_decl("_CRS", crs));
>  
>      Aml *aei = aml_resource_template();
> -    /* Pin 3 for power button */
> -    const uint32_t pin_list[1] = {3};
> +
> +    const uint32_t pin = GPIO_PIN_POWER_BUTTON;
>      aml_append(aei, aml_gpio_int(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
> -                                 AML_EXCLUSIVE, AML_PULL_UP, 0, pin_list, 1,
> +                                 AML_EXCLUSIVE, AML_PULL_UP, 0, &pin, 1,
>                                   "GPO0", NULL, 0));
>      aml_append(dev, aml_name_decl("_AEI", aei));
>  
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 719e83e6a1e7..687fe0bb8bc9 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -1004,7 +1004,7 @@ static void virt_powerdown_req(Notifier *n, void *opaque)
>      if (s->acpi_dev) {
>          acpi_send_event(s->acpi_dev, ACPI_POWER_DOWN_STATUS);
>      } else {
> -        /* use gpio Pin 3 for power button event */
> +        /* use gpio Pin for power button event */
>          qemu_set_irq(qdev_get_gpio_in(gpio_key_dev, 0), 1);
>      }
>  }
> @@ -1013,7 +1013,8 @@ static void create_gpio_keys(char *fdt, DeviceState *pl061_dev,
>                               uint32_t phandle)
>  {
>      gpio_key_dev = sysbus_create_simple("gpio-key", -1,
> -                                        qdev_get_gpio_in(pl061_dev, 3));
> +                                        qdev_get_gpio_in(pl061_dev,
> +                                                         GPIO_PIN_POWER_BUTTON));
>  
>      qemu_fdt_add_subnode(fdt, "/gpio-keys");
>      qemu_fdt_setprop_string(fdt, "/gpio-keys", "compatible", "gpio-keys");
> @@ -1024,7 +1025,7 @@ static void create_gpio_keys(char *fdt, DeviceState *pl061_dev,
>      qemu_fdt_setprop_cell(fdt, "/gpio-keys/poweroff", "linux,code",
>                            KEY_POWER);
>      qemu_fdt_setprop_cells(fdt, "/gpio-keys/poweroff",
> -                           "gpios", phandle, 3, 0);
> +                           "gpios", phandle, GPIO_PIN_POWER_BUTTON, 0);
>  }
>  
>  #define SECURE_GPIO_POWEROFF 0
> diff --git a/include/hw/arm/virt.h b/include/hw/arm/virt.h
> index ab961bb6a9b8..a4d937ed45ac 100644
> --- a/include/hw/arm/virt.h
> +++ b/include/hw/arm/virt.h
> @@ -47,6 +47,9 @@
>  /* See Linux kernel arch/arm64/include/asm/pvclock-abi.h */
>  #define PVTIME_SIZE_PER_CPU 64
>  
> +/* GPIO pins */
> +#define GPIO_PIN_POWER_BUTTON  3
> +
>  enum {
>      VIRT_FLASH,
>      VIRT_MEM,
> -- 
> 2.45.2