arm/virt: place power button pin number on a define

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>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Message-id: ef0e7f5fca6cd94eda415ecee670c3028c671b74.1723121692.git.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>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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));
 

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

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,