Commit ff92cfe7 authored by Aaron Lu's avatar Aaron Lu Committed by Rafael J. Wysocki
Browse files

ACPI / video: Allow forcing native backlight on non win8 machines 



The native backlight behavior (so not registering both the acpi-video
and the vendor backlight driver) can be useful on some non win8 machines
too, so change the behavior of the video.use_native_backlight=1 or 0
kernel cmdline option to be: if user has set video.use_native_backlight=1
or 0, use that no matter if it is a win8 system or not. Also, we will
put some known systems into the DMI table to make them either use native
backlight interface or not, and the use_native_backlight_dmi is used to
reflect that.

Original-by: default avatarHans de Goede <hdegoede@redhat.com>
Acked-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarAaron Lu <aaron.lu@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent 9eccca08

drivers/acpi/video.c

+13 −6
Original line number Diff line number Diff line
@@ -82,9 +82,15 @@ module_param(allow_duplicates, bool, 0644); 
 * For Windows 8 systems: used to decide if video module

 * should skip registering backlight interface of its own.

 */

static int use_native_backlight_param = -1;

enum {

	NATIVE_BACKLIGHT_NOT_SET = -1,

	NATIVE_BACKLIGHT_OFF,

	NATIVE_BACKLIGHT_ON,

};



static int use_native_backlight_param = NATIVE_BACKLIGHT_NOT_SET;

module_param_named(use_native_backlight, use_native_backlight_param, int, 0444);

static bool use_native_backlight_dmi = true;

static int use_native_backlight_dmi = NATIVE_BACKLIGHT_NOT_SET;



static int register_count;

static struct mutex video_list_lock;
@@ -237,15 +243,16 @@ static void acpi_video_switch_brightness(struct work_struct *work); 


static bool acpi_video_use_native_backlight(void)

{

	if (use_native_backlight_param != -1)

	if (use_native_backlight_param != NATIVE_BACKLIGHT_NOT_SET)

		return use_native_backlight_param;

	else

	else if (use_native_backlight_dmi != NATIVE_BACKLIGHT_NOT_SET)

		return use_native_backlight_dmi;

	return acpi_osi_is_win8();

}



bool acpi_video_verify_backlight_support(void)

{

	if (acpi_osi_is_win8() && acpi_video_use_native_backlight() &&

	if (acpi_video_use_native_backlight() &&

	    backlight_device_registered(BACKLIGHT_RAW))

		return false;

	return acpi_video_backlight_support();
@@ -414,7 +421,7 @@ static int __init video_set_bqc_offset(const struct dmi_system_id *d) 


static int __init video_disable_native_backlight(const struct dmi_system_id *d)

{

	use_native_backlight_dmi = false;

	use_native_backlight_dmi = NATIVE_BACKLIGHT_OFF;

	return 0;

}

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