1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #define LOG_TAG "lights" 18 #include <cutils/log.h> 19 #include <stdint.h> 20 #include <string.h> 21 #include <errno.h> 22 #include <fcntl.h> 23 #include <pthread.h> 24 #include <sys/ioctl.h> 25 #include <sys/types.h> 26 #include <hardware/lights.h> 27 28 static pthread_once_t g_init = PTHREAD_ONCE_INIT; 29 static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER; 30 31 char const *const LCD_FILE = "/sys/class/backlight/s5p_bl/brightness"; 32 33 static int write_int(char const *path, int value) 34 { 35 int fd; 36 static int already_warned; 37 38 already_warned = 0; 39 40 LOGV("write_int: path %s, value %d", path, value); 41 fd = open(path, O_RDWR); 42 43 if (fd >= 0) { 44 char buffer[20]; 45 int bytes = sprintf(buffer, "%d\n", value); 46 int amt = write(fd, buffer, bytes); 47 close(fd); 48 return amt == -1 ? -errno : 0; 49 } else { 50 if (already_warned == 0) { 51 LOGE("write_int failed to open %s\n", path); 52 already_warned = 1; 53 } 54 return -errno; 55 } 56 } 57 58 static int rgb_to_brightness(struct light_state_t const *state) 59 { 60 int color = state->color & 0x00ffffff; 61 62 return ((77*((color>>16) & 0x00ff)) 63 + (150*((color>>8) & 0x00ff)) + (29*(color & 0x00ff))) >> 8; 64 } 65 66 static int set_light_backlight(struct light_device_t *dev, 67 struct light_state_t const *state) 68 { 69 int err = 0; 70 int brightness = rgb_to_brightness(state); 71 72 pthread_mutex_lock(&g_lock); 73 err = write_int(LCD_FILE, brightness); 74 75 pthread_mutex_unlock(&g_lock); 76 return err; 77 } 78 79 static int close_lights(struct light_device_t *dev) 80 { 81 LOGV("close_light is called"); 82 if (dev) 83 free(dev); 84 85 return 0; 86 } 87 88 static int open_lights(const struct hw_module_t *module, char const *name, 89 struct hw_device_t **device) 90 { 91 int (*set_light)(struct light_device_t *dev, 92 struct light_state_t const *state); 93 94 LOGV("open_lights: open with %s", name); 95 96 if (0 == strcmp(LIGHT_ID_BACKLIGHT, name)) 97 set_light = set_light_backlight; 98 else 99 return -EINVAL; 100 101 pthread_mutex_init(&g_lock, NULL); 102 103 struct light_device_t *dev = malloc(sizeof(struct light_device_t)); 104 memset(dev, 0, sizeof(*dev)); 105 106 dev->common.tag = HARDWARE_DEVICE_TAG; 107 dev->common.version = 0; 108 dev->common.module = (struct hw_module_t *)module; 109 dev->common.close = (int (*)(struct hw_device_t *))close_lights; 110 dev->set_light = set_light; 111 112 *device = (struct hw_device_t *)dev; 113 114 return 0; 115 } 116 117 static struct hw_module_methods_t lights_module_methods = { 118 .open = open_lights, 119 }; 120 121 const struct hw_module_t HAL_MODULE_INFO_SYM = { 122 .tag = HARDWARE_MODULE_TAG, 123 .version_major = 1, 124 .version_minor = 0, 125 .id = LIGHTS_HARDWARE_MODULE_ID, 126 .name = "lights Module", 127 .author = "Google, Inc.", 128 .methods = &lights_module_methods, 129 }; 130