2 * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
4 * Copyright © 2014 Intel Corporation
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice shall be
15 * included in all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
30 PWM::PWM(int chipin, int pinin)
37 snprintf(buffer, 64, "/sys/class/pwm/pwmchip%d/export", chipid);
39 if((export_f = fopen(buffer, "w")) == NULL) {
40 fprintf(stderr, "Failed to open export for writing!\n");
42 fprintf(export_f, "%d", pin);
48 PWM::write(float percentage)
60 PWM::period(float seconds)
66 PWM::period_ms(int ms)
78 PWM::pulsewidth(float seconds)
84 PWM::pulsewidth_ms(int ms)
90 PWM::pulsewidth_us(int us)
96 PWM::enable(int enable)
108 PWM::write_period(int period)
114 PWM::write_duty(int duty)
116 if(duty_fp == NULL) {
119 fseek(duty_fp, SEEK_SET, 0);
120 fprintf(duty_fp, "%d", duty);
121 fseek(duty_fp, SEEK_SET, 0);
128 sprintf(bu, "/sys/class/pwm/pwmchip%d/pwm%d/duty_cycle", chipid, pin);
130 if((duty_fp = fopen(bu, "r+b")) == NULL) {