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      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  * Copyright (C) 2014 The  Linux Foundation. All rights reserved.
      4  *
      5  * Licensed under the Apache License, Version 2.0 (the "License");
      6  * you may not use this file except in compliance with the License.
      7  * You may obtain a copy of the License at
      8  *
      9  *      http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  * Unless required by applicable law or agreed to in writing, software
     12  * distributed under the License is distributed on an "AS IS" BASIS,
     13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  * See the License for the specific language governing permissions and
     15  * limitations under the License.
     16  */
     17 
     18 
     19 // #define LOG_NDEBUG 0
     20 
     21 #include <cutils/log.h>
     22 
     23 #include <stdint.h>
     24 #include <string.h>
     25 #include <unistd.h>
     26 #include <errno.h>
     27 #include <fcntl.h>
     28 #include <pthread.h>
     29 
     30 #include <sys/ioctl.h>
     31 #include <sys/types.h>
     32 
     33 #include <hardware/lights.h>
     34 
     35 /******************************************************************************/
     36 
     37 static pthread_once_t g_init = PTHREAD_ONCE_INIT;
     38 static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
     39 static struct light_state_t g_notification;
     40 static struct light_state_t g_battery;
     41 static int g_attention = 0;
     42 
     43 char const*const RED_LED_FILE
     44         = "/sys/class/leds/red/brightness";
     45 
     46 char const*const GREEN_LED_FILE
     47         = "/sys/class/leds/green/brightness";
     48 
     49 char const*const BLUE_LED_FILE
     50         = "/sys/class/leds/blue/brightness";
     51 
     52 char const*const LCD_FILE
     53         = "/sys/class/leds/lcd-backlight/brightness";
     54 
     55 char const*const BUTTON_FILE
     56         = "/sys/class/leds/button-backlight/brightness";
     57 
     58 char const*const RED_BLINK_FILE
     59         = "/sys/class/leds/red/blink";
     60 
     61 char const*const GREEN_BLINK_FILE
     62         = "/sys/class/leds/green/blink";
     63 
     64 char const*const BLUE_BLINK_FILE
     65         = "/sys/class/leds/blue/blink";
     66 
     67 /**
     68  * device methods
     69  */
     70 
     71 void init_globals(void)
     72 {
     73     // init the mutex
     74     pthread_mutex_init(&g_lock, NULL);
     75 }
     76 
     77 static int
     78 write_int(char const* path, int value)
     79 {
     80     int fd;
     81     static int already_warned = 0;
     82 
     83     fd = open(path, O_RDWR);
     84     if (fd >= 0) {
     85         char buffer[20];
     86         int bytes = sprintf(buffer, "%d\n", value);
     87         ssize_t amt = write(fd, buffer, (size_t)bytes);
     88         close(fd);
     89         return amt == -1 ? -errno : 0;
     90     } else {
     91         if (already_warned == 0) {
     92             ALOGE("write_int failed to open %s\n", path);
     93             already_warned = 1;
     94         }
     95         return -errno;
     96     }
     97 }
     98 
     99 static int
    100 is_lit(struct light_state_t const* state)
    101 {
    102     return state->color & 0x00ffffff;
    103 }
    104 
    105 static int
    106 rgb_to_brightness(struct light_state_t const* state)
    107 {
    108     int color = state->color & 0x00ffffff;
    109     return ((77*((color>>16)&0x00ff))
    110             + (150*((color>>8)&0x00ff)) + (29*(color&0x00ff))) >> 8;
    111 }
    112 
    113 static int
    114 set_light_backlight(struct light_device_t* dev,
    115         struct light_state_t const* state)
    116 {
    117     int err = 0;
    118     int brightness = rgb_to_brightness(state);
    119     if(!dev) {
    120         return -1;
    121     }
    122     pthread_mutex_lock(&g_lock);
    123     err = write_int(LCD_FILE, brightness);
    124     pthread_mutex_unlock(&g_lock);
    125     return err;
    126 }
    127 
    128 static int
    129 set_speaker_light_locked(struct light_device_t* dev,
    130         struct light_state_t const* state)
    131 {
    132     int red, green, blue;
    133     int blink;
    134     int onMS, offMS;
    135     unsigned int colorRGB;
    136 
    137     if(!dev) {
    138         return -1;
    139     }
    140 
    141     switch (state->flashMode) {
    142         case LIGHT_FLASH_TIMED:
    143             onMS = state->flashOnMS;
    144             offMS = state->flashOffMS;
    145             break;
    146         case LIGHT_FLASH_NONE:
    147         default:
    148             onMS = 0;
    149             offMS = 0;
    150             break;
    151     }
    152 
    153     colorRGB = state->color;
    154 
    155 #if 0
    156     ALOGD("set_speaker_light_locked mode %d, colorRGB=%08X, onMS=%d, offMS=%d\n",
    157             state->flashMode, colorRGB, onMS, offMS);
    158 #endif
    159 
    160     red = (colorRGB >> 16) & 0xFF;
    161     green = (colorRGB >> 8) & 0xFF;
    162     blue = colorRGB & 0xFF;
    163 
    164     if (onMS > 0 && offMS > 0) {
    165         blink = 1;
    166     } else {
    167         blink = 0;
    168     }
    169 
    170     if (blink) {
    171         if (red)
    172             write_int(RED_BLINK_FILE, blink);
    173         if (green)
    174             write_int(GREEN_BLINK_FILE, blink);
    175         if (blue)
    176             write_int(BLUE_BLINK_FILE, blink);
    177     } else {
    178         write_int(RED_LED_FILE, red);
    179         write_int(GREEN_LED_FILE, green);
    180         write_int(BLUE_LED_FILE, blue);
    181     }
    182 
    183     return 0;
    184 }
    185 
    186 static void
    187 handle_speaker_battery_locked(struct light_device_t* dev)
    188 {
    189     if (is_lit(&g_battery)) {
    190         set_speaker_light_locked(dev, &g_battery);
    191     } else {
    192         set_speaker_light_locked(dev, &g_notification);
    193     }
    194 }
    195 
    196 static int
    197 set_light_notifications(struct light_device_t* dev,
    198         struct light_state_t const* state)
    199 {
    200     pthread_mutex_lock(&g_lock);
    201     g_notification = *state;
    202     handle_speaker_battery_locked(dev);
    203     pthread_mutex_unlock(&g_lock);
    204     return 0;
    205 }
    206 
    207 static int
    208 set_light_attention(struct light_device_t* dev,
    209         struct light_state_t const* state)
    210 {
    211     pthread_mutex_lock(&g_lock);
    212     if (state->flashMode == LIGHT_FLASH_HARDWARE) {
    213         g_attention = state->flashOnMS;
    214     } else if (state->flashMode == LIGHT_FLASH_NONE) {
    215         g_attention = 0;
    216     }
    217     handle_speaker_battery_locked(dev);
    218     pthread_mutex_unlock(&g_lock);
    219     return 0;
    220 }
    221 
    222 static int
    223 set_light_buttons(struct light_device_t* dev,
    224         struct light_state_t const* state)
    225 {
    226     int err = 0;
    227     if(!dev) {
    228         return -1;
    229     }
    230     pthread_mutex_lock(&g_lock);
    231     err = write_int(BUTTON_FILE, state->color & 0xFF);
    232     pthread_mutex_unlock(&g_lock);
    233     return err;
    234 }
    235 
    236 /** Close the lights device */
    237 static int
    238 close_lights(struct light_device_t *dev)
    239 {
    240     if (dev) {
    241         free(dev);
    242     }
    243     return 0;
    244 }
    245 
    246 
    247 /******************************************************************************/
    248 
    249 /**
    250  * module methods
    251  */
    252 
    253 /** Open a new instance of a lights device using name */
    254 static int open_lights(const struct hw_module_t* module, char const* name,
    255         struct hw_device_t** device)
    256 {
    257     int (*set_light)(struct light_device_t* dev,
    258             struct light_state_t const* state);
    259 
    260     if (0 == strcmp(LIGHT_ID_BACKLIGHT, name))
    261         set_light = set_light_backlight;
    262     else if (0 == strcmp(LIGHT_ID_NOTIFICATIONS, name))
    263         set_light = set_light_notifications;
    264     else if (0 == strcmp(LIGHT_ID_BUTTONS, name))
    265         set_light = set_light_buttons;
    266     else if (0 == strcmp(LIGHT_ID_ATTENTION, name))
    267         set_light = set_light_attention;
    268     else
    269         return -EINVAL;
    270 
    271     pthread_once(&g_init, init_globals);
    272 
    273     struct light_device_t *dev = malloc(sizeof(struct light_device_t));
    274     memset(dev, 0, sizeof(*dev));
    275 
    276     dev->common.tag = HARDWARE_DEVICE_TAG;
    277     dev->common.version = 0;
    278     dev->common.module = (struct hw_module_t*)module;
    279     dev->common.close = (int (*)(struct hw_device_t*))close_lights;
    280     dev->set_light = set_light;
    281 
    282     *device = (struct hw_device_t*)dev;
    283     return 0;
    284 }
    285 
    286 static struct hw_module_methods_t lights_module_methods = {
    287     .open =  open_lights,
    288 };
    289 
    290 /*
    291  * The lights Module
    292  */
    293 struct hw_module_t HAL_MODULE_INFO_SYM = {
    294     .tag = HARDWARE_MODULE_TAG,
    295     .version_major = 1,
    296     .version_minor = 0,
    297     .id = LIGHTS_HARDWARE_MODULE_ID,
    298     .name = "lights Module",
    299     .author = "Google, Inc.",
    300     .methods = &lights_module_methods,
    301 };
    302