Colin Cross | ebf2cdf | 2012-03-12 13:58:29 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2012 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_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER; |
| 29 | |
| 30 | char const *const LCD_FILE = "/sys/class/backlight/pwm-backlight.0/brightness"; |
| 31 | |
| 32 | static int write_int(char const *path, int value) |
| 33 | { |
| 34 | int fd; |
| 35 | static int already_warned; |
| 36 | |
| 37 | ALOGV("write_int: path %s, value %d", path, value); |
| 38 | fd = open(path, O_RDWR); |
| 39 | |
| 40 | if (fd >= 0) { |
| 41 | char buffer[20]; |
| 42 | int bytes = sprintf(buffer, "%d\n", value); |
| 43 | int amt = write(fd, buffer, bytes); |
| 44 | close(fd); |
| 45 | return amt == -1 ? -errno : 0; |
| 46 | } else { |
| 47 | if (already_warned == 0) { |
| 48 | ALOGE("write_int failed to open %s\n", path); |
| 49 | already_warned = 1; |
| 50 | } |
| 51 | return -errno; |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | static int rgb_to_brightness(struct light_state_t const *state) |
| 56 | { |
| 57 | /* use max of the RGB components for brightness */ |
| 58 | int color = state->color & 0x00ffffff; |
| 59 | int red = (color >> 16) & 0x000000ff; |
| 60 | int green = (color >> 8) & 0x000000ff; |
| 61 | int blue = color & 0x000000ff; |
| 62 | |
| 63 | int brightness = red; |
| 64 | if (green > brightness) |
| 65 | brightness = green; |
| 66 | if (blue > brightness) |
| 67 | brightness = blue; |
| 68 | |
| 69 | return brightness; |
| 70 | } |
| 71 | |
| 72 | static int set_light_backlight(struct light_device_t *dev, |
| 73 | struct light_state_t const *state) |
| 74 | { |
| 75 | int err = 0; |
| 76 | int brightness = rgb_to_brightness(state); |
| 77 | |
| 78 | pthread_mutex_lock(&g_lock); |
| 79 | err = write_int(LCD_FILE, brightness); |
| 80 | |
| 81 | pthread_mutex_unlock(&g_lock); |
| 82 | return err; |
| 83 | } |
| 84 | |
| 85 | static int close_lights(struct hw_device_t *dev) |
| 86 | { |
| 87 | ALOGV("close_light is called"); |
| 88 | free(dev); |
| 89 | |
| 90 | return 0; |
| 91 | } |
| 92 | |
| 93 | static int open_lights(const struct hw_module_t *module, char const *name, |
| 94 | struct hw_device_t **device) |
| 95 | { |
| 96 | int (*set_light)(struct light_device_t *dev, |
| 97 | struct light_state_t const *state); |
| 98 | |
| 99 | if (strcmp(LIGHT_ID_BACKLIGHT, name) == 0) |
| 100 | set_light = set_light_backlight; |
| 101 | else |
| 102 | return -EINVAL; |
| 103 | |
| 104 | struct light_device_t *dev = malloc(sizeof(struct light_device_t)); |
| 105 | if (!dev) |
| 106 | return -ENOMEM; |
| 107 | memset(dev, 0, sizeof(*dev)); |
| 108 | |
| 109 | dev->common.tag = HARDWARE_DEVICE_TAG; |
| 110 | dev->common.version = 0; |
| 111 | dev->common.module = (struct hw_module_t *)module; |
| 112 | dev->common.close = close_lights; |
| 113 | dev->set_light = set_light; |
| 114 | |
| 115 | *device = (struct hw_device_t *)dev; |
| 116 | |
| 117 | return 0; |
| 118 | } |
| 119 | |
| 120 | static struct hw_module_methods_t lights_module_methods = { |
| 121 | .open = open_lights, |
| 122 | }; |
| 123 | |
| 124 | struct hw_module_t HAL_MODULE_INFO_SYM = { |
| 125 | .tag = HARDWARE_MODULE_TAG, |
| 126 | .version_major = 1, |
| 127 | .version_minor = 0, |
| 128 | .id = LIGHTS_HARDWARE_MODULE_ID, |
| 129 | .name = "lights Module", |
| 130 | .author = "Google, Inc.", |
| 131 | .methods = &lights_module_methods, |
| 132 | }; |