drivers/acpi/wakeup.c

Source file repositories/reference/linux-study-clean/drivers/acpi/wakeup.c

File Facts

System
Linux kernel
Corpus path
drivers/acpi/wakeup.c
Extension
.c
Size
4702 bytes
Lines
172
Domain
Driver Families
Bucket
drivers/acpi
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct acpi_wakeup_handler {
	struct list_head list_node;
	bool (*wakeup)(void *context);
	void *context;
};

static LIST_HEAD(acpi_wakeup_handler_head);
static DEFINE_MUTEX(acpi_wakeup_handler_mutex);

/*
 * We didn't lock acpi_device_lock in the file, because it invokes oops in
 * suspend/resume and isn't really required as this is called in S-state. At
 * that time, there is no device hotplug
 **/

/**
 * acpi_enable_wakeup_devices - Enable wake-up device GPEs.
 * @sleep_state: ACPI system sleep state.
 *
 * Enable wakeup device power of devices with the state.enable flag set and set
 * the wakeup enable mask bits in the GPE registers that correspond to wakeup
 * devices.
 */
void acpi_enable_wakeup_devices(u8 sleep_state)
{
	struct acpi_device *dev, *tmp;

	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
				 wakeup_list) {
		if (!dev->wakeup.flags.valid
		    || sleep_state > dev->wakeup.sleep_state
		    || !(device_may_wakeup(&dev->dev)
			 || dev->wakeup.prepare_count))
			continue;

		if (device_may_wakeup(&dev->dev))
			acpi_enable_wakeup_device_power(dev, sleep_state);

		/* The wake-up power should have been enabled already. */
		acpi_set_gpe_wake_mask(dev->wakeup.gpe_device, dev->wakeup.gpe_number,
				ACPI_GPE_ENABLE);
	}
}

/**
 * acpi_disable_wakeup_devices - Disable devices' wakeup capability.
 * @sleep_state: ACPI system sleep state.
 */
void acpi_disable_wakeup_devices(u8 sleep_state)
{
	struct acpi_device *dev, *tmp;

	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
				 wakeup_list) {
		if (!dev->wakeup.flags.valid
		    || sleep_state > dev->wakeup.sleep_state
		    || !(device_may_wakeup(&dev->dev)
			 || dev->wakeup.prepare_count))
			continue;

		acpi_set_gpe_wake_mask(dev->wakeup.gpe_device, dev->wakeup.gpe_number,
				ACPI_GPE_DISABLE);

		if (device_may_wakeup(&dev->dev))
			acpi_disable_wakeup_device_power(dev);
	}
}

int __init acpi_wakeup_device_init(void)
{
	struct acpi_device *dev, *tmp;

	mutex_lock(&acpi_device_lock);
	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
				 wakeup_list) {
		if (device_can_wakeup(&dev->dev)) {
			/* Button GPEs are supposed to be always enabled. */
			acpi_enable_gpe(dev->wakeup.gpe_device,
					dev->wakeup.gpe_number);
			device_set_wakeup_enable(&dev->dev, true);
		}
	}
	mutex_unlock(&acpi_device_lock);
	return 0;
}

/**
 * acpi_register_wakeup_handler - Register wakeup handler
 * @wake_irq: The IRQ through which the device may receive wakeups
 * @wakeup:   Wakeup-handler to call when the SCI has triggered a wakeup

Annotation

Implementation Notes