src/pca9685.c

   1 /*
   2  * Copyright (c) 2017 Samsung Electronics Co., Ltd.
   3  *
   4  * Contact: Jeonghoon Park <jh1979.park@samsung.com>
   5  *
   6  * Licensed under the Flora License, Version 1.1 (the License);
   7  * you may not use this file except in compliance with the License.
   8  * You may obtain a copy of the License at
   9  *
  10  * http://floralicense.org/license/
  11  *
  12  * Unless required by applicable law or agreed to in writing, software
  13  * distributed under the License is distributed on an AS IS BASIS,
  14  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  * See the License for the specific language governing permissions and
  16  * limitations under the License.
  17  */
  18
  19 #include <stdio.h>
  20 #include <unistd.h>
  21 #include <math.h>
  22 #include <peripheral_io.h>
  23 #include "log.h"
  24
  25 #define RPI3_I2C_BUS 1
  26
  27 /* Registers/etc: */
  28 #define PCA9685_ADDRESS    0x40
  29 #define MODE1              0x00
  30 #define MODE2              0x01
  31 #define SUBADR1            0x02
  32 #define SUBADR2            0x03
  33 #define SUBADR3            0x04
  34 #define PRESCALE           0xFE
  35 #define LED0_ON_L          0x06
  36 #define LED0_ON_H          0x07
  37 #define LED0_OFF_L         0x08
  38 #define LED0_OFF_H         0x09
  39 #define ALL_LED_ON_L       0xFA
  40 #define ALL_LED_ON_H       0xFB
  41 #define ALL_LED_OFF_L      0xFC
  42 #define ALL_LED_OFF_H      0xFD
  43
  44 /* Bits: */
  45 #define RESTART            0x80
  46 #define SLEEP              0x10
  47 #define ALLCALL            0x01
  48 #define INVRT              0x10
  49 #define OUTDRV             0x04
  50
  51 static peripheral_i2c_h g_i2c_h = NULL;
  52
  53 int pca9685_set_frequency(unsigned int freq_hz)
  54 {
  55         int ret = PERIPHERAL_ERROR_NONE;
  56         double prescale_value = 0.0;
  57         int prescale = 0;
  58         uint8_t oldmode = 0;
  59         uint8_t newmode = 0;
  60
  61         prescale_value = 25000000.0;    // 25MHz
  62         prescale_value /= 4096.0;       // 12-bit
  63         prescale_value /= (double)freq_hz;
  64         prescale_value -= 1.0;
  65
  66         prescale = (int)floor(prescale_value + 0.5);
  67
  68         ret = peripheral_i2c_read_register_byte(g_i2c_h, MODE1, &oldmode);
  69         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to read register");
  70
  71         newmode = (oldmode & 0x7F) | 0x10; // sleep
  72         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE1, newmode); // go to sleep
  73         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
  74
  75         ret = peripheral_i2c_write_register_byte(g_i2c_h, PRESCALE, prescale);
  76         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
  77
  78         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE1, oldmode);
  79         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
  80
  81         usleep(500);
  82
  83         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE1, (oldmode | 0x80));
  84         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
  85
  86         return 0;
  87 }
  88
  89 int pca9685_set_value_to_channel(unsigned int channel, int on, int off)
  90 {
  91         int ret = PERIPHERAL_ERROR_NONE;
  92         retvm_if(g_i2c_h == NULL, -1, "Not initialized yet");
  93
  94         ret = peripheral_i2c_write_register_byte(g_i2c_h,
  95                         LED0_ON_L + 4*channel, on & 0xFF);
  96         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
  97
  98         ret = peripheral_i2c_write_register_byte(g_i2c_h,
  99                         LED0_ON_H + 4*channel, on >> 8);
 100         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 101
 102         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 103                         LED0_OFF_L + 4*channel, off & 0xFF);
 104         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 105
 106         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 107                         LED0_OFF_H + 4*channel, off >> 8);
 108         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 109
 110         return 0;
 111 }
 112
 113 int pca9685_set_value_to_all(int on, int off)
 114 {
 115         int ret = PERIPHERAL_ERROR_NONE;
 116         retvm_if(g_i2c_h == NULL, -1, "Not initialized yet");
 117
 118         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 119                 ALL_LED_ON_L, on & 0xFF);
 120         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 121
 122         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 123                 ALL_LED_ON_H, on >> 8);
 124         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 125
 126         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 127                 ALL_LED_OFF_L, off & 0xFF);
 128         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 129
 130         ret = peripheral_i2c_write_register_byte(g_i2c_h,
 131                 ALL_LED_OFF_H, off >> 8);
 132         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 133
 134         return 0;
 135 }
 136
 137 int pca9685_init(void)
 138 {
 139         uint8_t mode1 = 0;
 140
 141         int ret = PERIPHERAL_ERROR_NONE;
 142         ret = peripheral_i2c_open(RPI3_I2C_BUS, PCA9685_ADDRESS, &g_i2c_h);
 143         if (ret != PERIPHERAL_ERROR_NONE) {
 144                 _E("failed to open pca9685-[bus:%d, addr:%d]",
 145                         RPI3_I2C_BUS, PCA9685_ADDRESS);
 146                 return -1;
 147         }
 148         ret = pca9685_set_value_to_all(0, 0);
 149         retvm_if(ret, -1, "failed to set value to register");
 150
 151         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE2, OUTDRV);
 152         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 153
 154         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE1, ALLCALL);
 155         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 156
 157         usleep(500); // wait for oscillator
 158
 159         ret = peripheral_i2c_read_register_byte(g_i2c_h, MODE1, &mode1);
 160         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to read register");
 161
 162         mode1 = mode1 & (~SLEEP); // # wake up (reset sleep)
 163         ret = peripheral_i2c_write_register_byte(g_i2c_h, MODE1, mode1);
 164         retvm_if(ret != PERIPHERAL_ERROR_NONE, -1, "failed to write register");
 165
 166         usleep(500); // wait for oscillator
 167
 168         return 0;
 169 }
 170
 171 int pca9685_fini(void)
 172 {
 173         if (g_i2c_h) {
 174                 peripheral_i2c_close(g_i2c_h);
 175                 g_i2c_h = NULL;
 176         }
 177
 178         return 0;
 179 }