Calling _WAK on boot

[w4v3 <vv4v3@xxxxxxxxxxxxxx>]

Hi everyone,

As I understand ACPI spec §16.3.3, the _WAK method should also
be called when waking up from S5. Currently this doesn't
seem to be the case.

On my device (Lenovo Yoga 7i), the brightness hotkeys depend
on initialization carried out in _WAK, so they currently only
work after resuming from S3 or S4 sleep, but not after booting
normally.

I really don't know what would be the right way to do this,
but as an example, patching the acpi_init function as follows
seems to work fine.

--- linux-pm.orig/drivers/acpi/bus.c
+++ linux-pm/drivers/acpi/bus.c
@@ -1094,6 +1094,7 @@
 	acpi_debugfs_init();
 	acpi_sleep_proc_init();
 	acpi_wakeup_device_init();
+        acpi_leave_sleep_state(ACPI_STATE_S5);
 	return 0;
 }