ACPI: video: Add auto_detect arg to __acpi_video_get_backlight_type()

Allow callers of __acpi_video_get_backlight_type() to pass a pointer
to a bool which will get set to false if the backlight-type comes from
the cmdline or a DMI quirk and set to true if auto-detection was used.

And make __acpi_video_get_backlight_type() non static so that it can
be called directly outside of video_detect.c .

While at it turn the acpi_video_get_backlight_type() and
acpi_video_backlight_use_native() wrappers into static inline functions
in include/acpi/video.h, so that we need to export one less symbol.

Fixes: 5aa9d943e9b6 ("ACPI: video: Don't enable fallback path for creating ACPI backlight by default")
Cc: All applicable <stable@vger.kernel.org>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 8 insertions, 13 deletions

diff --git a/drivers/acpi/video_detect.c b/drivers/acpi/video_detect.c
index fd7cbce8076e..f7c218dd8742 100644
--- a/drivers/acpi/video_detect.c
+++ b/drivers/acpi/video_detect.c
@@ -782,7 +782,7 @@ static bool prefer_native_over_acpi_video(void)
  * Determine which type of backlight interface to use on this system,
  * First check cmdline, then dmi quirks, then do autodetect.
  */
-static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
+enum acpi_backlight_type __acpi_video_get_backlight_type(bool native, bool *auto_detect)
 {
 	static DEFINE_MUTEX(init_mutex);
 	static bool nvidia_wmi_ec_present;
@@ -807,6 +807,9 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 		native_available = true;
 	mutex_unlock(&init_mutex);
 
+	if (auto_detect)
+		*auto_detect = false;
+
 	/*
 	 * The below heuristics / detection steps are in order of descending
 	 * presedence. The commandline takes presedence over anything else.
@@ -818,6 +821,9 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 	if (acpi_backlight_dmi != acpi_backlight_undef)
 		return acpi_backlight_dmi;
 
+	if (auto_detect)
+		*auto_detect = true;
+
 	/* Special cases such as nvidia_wmi_ec and apple gmux. */
 	if (nvidia_wmi_ec_present)
 		return acpi_backlight_nvidia_wmi_ec;
@@ -837,15 +843,4 @@ static enum acpi_backlight_type __acpi_video_get_backlight_type(bool native)
 	/* No ACPI video/native (old hw), use vendor specific fw methods. */
 	return acpi_backlight_vendor;
 }
-
-enum acpi_backlight_type acpi_video_get_backlight_type(void)
-{
-	return __acpi_video_get_backlight_type(false);
-}
-EXPORT_SYMBOL(acpi_video_get_backlight_type);
-
-bool acpi_video_backlight_use_native(void)
-{
-	return __acpi_video_get_backlight_type(true) == acpi_backlight_native;
-}
-EXPORT_SYMBOL(acpi_video_backlight_use_native);
+EXPORT_SYMBOL(__acpi_video_get_backlight_type);