linux/include/acpi/video.h
Hans de Goede 90b066b15e ACPI / video: Add a acpi_video_handles_brightness_key_presses() helper
Several drivers want to know if the acpi-video is generating key-presses
for brightness change hotkeys to avoid sending double key-events to
userspace for these. Currently these driver use this construct for this:

	if (acpi_video_get_backlight_type() == acpi_backlight_vendor)
		report_brightness_key_event();

This indirect way of detecting if acpi-video is active does not make the
code easier to understand, and in some cases it is wrong because just
because the preferred type != vendor does not mean that acpi-video is
actually listening for brightness events, e.g. there may be no acpi-video
bus on the system at all.

This commit adds a acpi_video_handles_brightness_key_presses() helper
function, making the code needing this functionality both easier to read
and more correct.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-01-01 03:14:51 +01:00

58 lines
1.6 KiB
C

#ifndef __ACPI_VIDEO_H
#define __ACPI_VIDEO_H
#include <linux/errno.h> /* for ENODEV */
#include <linux/types.h> /* for bool */
struct acpi_device;
#define ACPI_VIDEO_CLASS "video"
#define ACPI_VIDEO_DISPLAY_CRT 1
#define ACPI_VIDEO_DISPLAY_TV 2
#define ACPI_VIDEO_DISPLAY_DVI 3
#define ACPI_VIDEO_DISPLAY_LCD 4
#define ACPI_VIDEO_DISPLAY_LEGACY_MONITOR 0x0100
#define ACPI_VIDEO_DISPLAY_LEGACY_PANEL 0x0110
#define ACPI_VIDEO_DISPLAY_LEGACY_TV 0x0200
enum acpi_backlight_type {
acpi_backlight_undef = -1,
acpi_backlight_none = 0,
acpi_backlight_video,
acpi_backlight_vendor,
acpi_backlight_native,
};
#if IS_ENABLED(CONFIG_ACPI_VIDEO)
extern int acpi_video_register(void);
extern void acpi_video_unregister(void);
extern int acpi_video_get_edid(struct acpi_device *device, int type,
int device_id, void **edid);
extern enum acpi_backlight_type acpi_video_get_backlight_type(void);
extern void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type);
extern bool acpi_video_handles_brightness_key_presses(void);
#else
static inline int acpi_video_register(void) { return 0; }
static inline void acpi_video_unregister(void) { return; }
static inline int acpi_video_get_edid(struct acpi_device *device, int type,
int device_id, void **edid)
{
return -ENODEV;
}
static inline enum acpi_backlight_type acpi_video_get_backlight_type(void)
{
return acpi_backlight_vendor;
}
static inline void acpi_video_set_dmi_backlight_type(enum acpi_backlight_type type)
{
}
static inline bool acpi_video_handles_brightness_key_presses(void)
{
return false;
}
#endif
#endif