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/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <hardware_legacy/led.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <stdio.h>
#define LOG_TAG "LED"
#include <utils/Log.h>
const char* const AMBER_BRIGHTNESS_FILE = "/sys/class/leds/amber/brightness";
const char* const RED_BRIGHTNESS_FILE = "/sys/class/leds/red/brightness";
const char* const GREEN_BRIGHTNESS_FILE = "/sys/class/leds/green/brightness";
const char* const BLUE_BRIGHTNESS_FILE = "/sys/class/leds/blue/brightness";
const char* const BLINK_ENABLE_FILE = "/sys/class/leds/red/device/blink";
const char* const BLINK_FREQ_FILE = "/sys/class/leds/red/device/grpfreq";
const char* const BLINK_PWM_FILE = "/sys/class/leds/red/device/grppwm";
static int
write_string(const char* file, const char* string, int len)
{
int fd;
ssize_t amt;
fd = open(file, O_RDWR);
if (fd < 0) {
LOGE("open failed errno: %d\n", errno);
return errno;
}
amt = write(fd, string, len);
if (amt < 0) {
LOGE("write failed errno: %d\n", errno);
}
close(fd);
return amt >= 0 ? 0 : errno;
}
int trout_set_led_state(unsigned colorARGB, int onMS, int offMS)
{
int len;
char buf[30];
int alpha, red, green, blue;
int blink, freq, pwm;
LOGV("set_led_state colorARGB=%08X, onMS=%d, offMS=%d\n", colorARGB, onMS, offMS);
// alpha of 0 or color of 0 means off
if ((colorARGB & 0xff000000) == 0 || (colorARGB & 0x00ffffff) == 0) {
onMS = 0;
offMS = 0;
}
red = (colorARGB >> 16) & 0xFF;
green = (colorARGB >> 8) & 0xFF;
blue = colorARGB & 0xFF;
len = sprintf(buf, "%d", red);
write_string(RED_BRIGHTNESS_FILE, buf, len);
len = sprintf(buf, "%d", green);
write_string(GREEN_BRIGHTNESS_FILE, buf, len);
len = sprintf(buf, "%d", blue);
write_string(BLUE_BRIGHTNESS_FILE, buf, len);
if (onMS > 0 && offMS > 0) {
int totalMS = onMS + offMS;
// the LED appears to blink about once per second if freq is 20
// 1000ms / 20 = 50
freq = totalMS / 50;
// pwm specifies the ratio of ON versus OFF
// pwm = 0 -> always off
// pwm = 255 => always on
pwm = (onMS * 255) / totalMS;
// the low 4 bits are ignored, so round up if necessary
if (pwm > 0 && pwm < 16)
pwm = 16;
blink = 1;
} else {
blink = 0;
freq = 0;
pwm = 0;
}
if (blink) {
len = sprintf(buf, "%d", freq);
write_string(BLINK_FREQ_FILE, buf, len);
len = sprintf(buf, "%d", pwm);
write_string(BLINK_PWM_FILE, buf, len);
}
len = sprintf(buf, "%d", blink);
write_string(BLINK_ENABLE_FILE, buf, len);
return 0;
}
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