Merge tag 'acpi-4.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "These are two watchdog-related fixes, fix for a backlight regression
  from the 4.16 cycle that unfortunately was propagated to -stable and a
  button module modification to prevent graphics driver modules from
  failing to load due to unmet dependencies if ACPI is disabled from the
  kernel command line.

  Specifics:

   - Change the ACPI subsystem initialization ordering to initialize the
     WDAT watchodg before reserving PNP motherboard resources so as to
     allow the watchdog to allocate its resources before the PNP code
     gets to them and prevents it from working correctly (Mika
     Westerberg).

   - Add a quirk for Lenovo Z50-70 to use the iTCO watchdog instead of
     the WDAT one which conflicts with the RTC on that platform (Mika
     Westerberg).

   - Avoid breaking backlight handling on Dell XPS 13 2013 model by
     allowing laptops to use the ACPI backlight by default even if they
     are Windows 8-ready in principle (Hans de Goede)"

* tag 'acpi-4.17-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI / video: Only default only_lcd to true on Win8-ready _desktops_
  ACPI / button: make module loadable when booted in non-ACPI mode
  ACPI / watchdog: Prefer iTCO_wdt on Lenovo Z50-70
  ACPI / scan: Initialize watchdog before PNP

1 files changed, 23 insertions, 1 deletions

diff --git a/drivers/acpi/button.c b/drivers/acpi/button.c
index e1eee7a60fad..f1cc4f9d31cd 100644
--- a/drivers/acpi/button.c
+++ b/drivers/acpi/button.c
@@ -635,4 +635,26 @@ module_param_call(lid_init_state,
 		  NULL, 0644);
 MODULE_PARM_DESC(lid_init_state, "Behavior for reporting LID initial state");
 
-module_acpi_driver(acpi_button_driver);
+static int acpi_button_register_driver(struct acpi_driver *driver)
+{
+	/*
+	 * Modules such as nouveau.ko and i915.ko have a link time dependency
+	 * on acpi_lid_open(), and would therefore not be loadable on ACPI
+	 * capable kernels booted in non-ACPI mode if the return value of
+	 * acpi_bus_register_driver() is returned from here with ACPI disabled
+	 * when this driver is built as a module.
+	 */
+	if (acpi_disabled)
+		return 0;
+
+	return acpi_bus_register_driver(driver);
+}
+
+static void acpi_button_unregister_driver(struct acpi_driver *driver)
+{
+	if (!acpi_disabled)
+		acpi_bus_unregister_driver(driver);
+}
+
+module_driver(acpi_button_driver, acpi_button_register_driver,
+	       acpi_button_unregister_driver);