ardupilot/libraries/AP_Notify/NCP5623.cpp

/*
  NCP5623 I2C LED driver
*/
/*
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "NCP5623.h"
#include <utility>

#include <AP_HAL/AP_HAL.h>

extern const AP_HAL::HAL& hal;

#define NCP5623_LED_BRIGHT  0x1f    // full brightness
#define NCP5623_LED_MEDIUM  0x18    // medium brightness
#define NCP5623_LED_DIM     0x0f    // dim
#define NCP5623_LED_OFF     0x00    // off

#define NCP5623_LED_I2C_ADDR 0x38    // default I2C bus address
#define NCP5623_C_LED_I2C_ADDR 0x39    // default I2C bus address for the NCP5623C

#define NCP5623_LED_PWM0    0x40    // pwm0 register
#define NCP5623_LED_PWM1    0x60    // pwm1 register
#define NCP5623_LED_PWM2    0x80    // pwm2 register
#define NCP5623_LED_ENABLE  0x20    // enable register

NCP5623::NCP5623(uint8_t bus)
    : RGBLed(NCP5623_LED_OFF, NCP5623_LED_BRIGHT, NCP5623_LED_MEDIUM, NCP5623_LED_DIM)
    , _bus(bus)
{
}

bool NCP5623::write(uint8_t reg, uint8_t data)
{
    uint8_t msg[1] = { 0x00 };
    // scale to 0 to 0x1F
    data = (data * 255U) / 0x1FU;
    msg[0] = ((reg & 0xe0) | (data & 0x1f));
    bool ret = _dev->transfer(msg, 1, nullptr, 0);
    return ret;
}

bool NCP5623::write_pwm(uint8_t _rgb[3])
{
    uint8_t reg = NCP5623_LED_PWM0;
    for (uint8_t i=0; i<3; i++) {
        if (!write(reg+i*0x20, _rgb[i])) {
            return false;
        }
    }
    return true;
}

bool NCP5623::init(void)
{
    uint8_t addrs[] = { NCP5623_LED_I2C_ADDR, NCP5623_C_LED_I2C_ADDR };
    for (uint8_t i=0; i<ARRAY_SIZE(addrs); i++) {
        // first look for led on external bus
        _dev = std::move(hal.i2c_mgr->get_device(_bus, addrs[i]));
        if (!_dev) {
            continue;
        }

        _dev->get_semaphore()->take_blocking();
        _dev->set_retries(10);

        // enable the led
        bool ret = write(NCP5623_LED_ENABLE, 0x1f);
        if (!ret) {
            _dev->get_semaphore()->give();
            continue;
        }

        // update the red, green and blue values to zero
        uint8_t off[3] = { _led_off, _led_off, _led_off };
        ret = write_pwm(off);

        _dev->set_retries(1);

        // give back i2c semaphore
        _dev->get_semaphore()->give();

        if (ret) {
            _dev->register_periodic_callback(20000, FUNCTOR_BIND_MEMBER(&NCP5623::_timer, void));
        }
        return true;
    }

    return false;
}

// set_rgb - set color as a combination of red, green and blue values
bool NCP5623::hw_set_rgb(uint8_t red, uint8_t green, uint8_t blue)
{
    rgb[0] = red;
    rgb[1] = green;
    rgb[2] = blue;
    _need_update = true;
    return true;
}

void NCP5623::_timer(void)
{
    if (!_need_update) {
        return;
    }
    _need_update = false;

    write_pwm(rgb);
}