Merge branch 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86

Pull x86 platform driver updates from Matthew Garrett:
 "Some significant updates to samsung-laptop, additional hardware
  support for Toshibas, misc updates to various hardware and a new
  backlight driver for some Apple machines."

Fix up trivial conflicts: geode Geos update happening next to net5501
support, and MSIC thermal platform support added twice.

* 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86: (77 commits)
  acer-wmi: add quirk table for video backlight vendor mode
  drivers/platform/x86/amilo-rfkill.c::amilo_rfkill_probe() avoid NULL deref
  samsung-laptop: unregister ACPI video module for some well known laptops
  acer-wmi: No wifi rfkill on Sony machines
  thinkpad-acpi: recognize Lenovo as version string in newer V-series BIOS
  asus-wmi: don't update power and brightness when using scalar
  eeepc-wmi: split et2012 specific hacks
  eeepc-wmi: refine quirks handling
  asus-nb-wmi: set panel_power correctly
  asus-wmi: move WAPF variable into quirks_entry
  asus-wmi: store backlight power status for AIO machine
  asus-wmi: add scalar board brightness adj. support
  samsung-laptop: cleanup return type: mode_t vs umode_t
  drivers, samsung-laptop: fix usage of isalnum
  drivers, samsung-laptop: fix initialization of sabi_data in sabi_set_commandb
  asus-wmi: on/off bit is not set when reading the value
  eeepc-wmi: add extra keymaps for EP121
  asus-nb-wmi: ignore useless keys
  acer-wmi: support Lenovo ideapad S205 Brazos wifi switch
  acer-wmi: fix out of input parameter size when set
  ...

1 files changed, 21 insertions, 2 deletions

diff --git a/drivers/video/backlight/apple_bl.c b/drivers/video/backlight/apple_bl.c
index be98d15..a523b25 100644
--- a/drivers/video/backlight/apple_bl.c
+++ b/drivers/video/backlight/apple_bl.c
@@ -24,6 +24,7 @@
 #include <linux/io.h>
 #include <linux/pci.h>
 #include <linux/acpi.h>
+#include <linux/atomic.h>
 
 static struct backlight_device *apple_backlight_device;
 
@@ -221,14 +222,32 @@ static struct acpi_driver apple_bl_driver = {
 	},
 };
 
+static atomic_t apple_bl_registered = ATOMIC_INIT(0);
+
+int apple_bl_register(void)
+{
+	if (atomic_xchg(&apple_bl_registered, 1) == 0)
+		return acpi_bus_register_driver(&apple_bl_driver);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(apple_bl_register);
+
+void apple_bl_unregister(void)
+{
+	if (atomic_xchg(&apple_bl_registered, 0) == 1)
+		acpi_bus_unregister_driver(&apple_bl_driver);
+}
+EXPORT_SYMBOL_GPL(apple_bl_unregister);
+
 static int __init apple_bl_init(void)
 {
-	return acpi_bus_register_driver(&apple_bl_driver);
+	return apple_bl_register();
 }
 
 static void __exit apple_bl_exit(void)
 {
-	acpi_bus_unregister_driver(&apple_bl_driver);
+	apple_bl_unregister();
 }
 
 module_init(apple_bl_init);