1 /* 2 * libbacklight - userspace interface to Linux backlight control 3 * 4 * Copyright © 2012 Intel Corporation 5 * Copyright 2010 Red Hat <mjg@redhat.com> 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the "Software"), 9 * to deal in the Software without restriction, including without limitation 10 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 11 * and/or sell copies of the Software, and to permit persons to whom the 12 * Software is furnished to do so, subject to the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the next 15 * paragraph) shall be included in all copies or substantial portions of the 16 * Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 19 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 21 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 22 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 23 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 24 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 25 * DEALINGS IN THE SOFTWARE. 26 * 27 * Authors: 28 * Matthew Garrett <mjg@redhat.com> 29 * Tiago Vignatti <vignatti@freedesktop.org> 30 */ 31 #ifndef LIBBACKLIGHT_H 32 #define LIBBACKLIGHT_H 33 #include <libudev.h> 34 #include <stdint.h> 35 36 #ifdef __cplusplus 37 extern "C" { 38 #endif 39 40 enum backlight_type { 41 BACKLIGHT_RAW, 42 BACKLIGHT_PLATFORM, 43 BACKLIGHT_FIRMWARE 44 }; 45 46 struct backlight { 47 char *path; 48 int max_brightness; 49 int brightness; 50 enum backlight_type type; 51 }; 52 53 /* 54 * Find and set up a backlight for a valid udev connector device, i.e. one 55 * matching drm subsystem and with status of connected. 56 */ 57 struct backlight *backlight_init(struct udev_device *drm_device, 58 uint32_t connector_type); 59 60 /* Free backlight resources */ 61 void backlight_destroy(struct backlight *backlight); 62 63 /* Provide the maximum backlight value */ 64 long backlight_get_max_brightness(struct backlight *backlight); 65 66 /* Provide the cached backlight value */ 67 long backlight_get_brightness(struct backlight *backlight); 68 69 /* Provide the hardware backlight value */ 70 long backlight_get_actual_brightness(struct backlight *backlight); 71 72 /* Set the backlight to a value between 0 and max */ 73 long backlight_set_brightness(struct backlight *backlight, long brightness); 74 75 #ifdef __cplusplus 76 } 77 #endif 78 79 #endif /* LIBBACKLIGHT_H */ 80