linux-imx

ACPI / PM: Use Low Power S0 Idle on more systems

Some systems don't support the ACPI_LPS0_ENTRY and ACPI_LPS0_EXIT
functions in their Low Power S0 Idle _DSM, but still expect EC
events to be processed in the suspend-to-idle state for power button
wakeup (among other things) to work.  Surface Pro3 turns out to be
one of them.

Fortunately, it still provides Low Power S0 Idle _DSM with the screen
on/off functions supported, so modify the ACPI suspend-to-idle to use
the Low Power S0 Idle code path for all systems supporting the
ACPI_LPS0_ENTRY and ACPI_LPS0_EXIT or the ACPI_LPS0_SCREEN_OFF and
ACPI_LPS0_SCREEN_ON functions in their Low Power S0 Idle _DSM.

Potentially, that will cause more systems to use suspend-to-idle by
default, so some future corrections may be necessary if it leads
to issues, but let it remain more straightforward for now.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=198389#add_comment
Reported-by: Valentin Manea <valy@mrs.ro>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Valentin Manea <valy@mrs.ro>