2 * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
3 * Copyright (c) 2014 Intel Corporation.
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
13 * The above copyright notice and this permission notice shall be
14 * included in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
31 #include "mraa_internal.h"
34 #define SYSFS_PWM "/sys/class/pwm"
37 mraa_pwm_setup_duty_fp(mraa_pwm_context dev)
40 snprintf(bu,MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/duty_cycle", dev->chipid, dev->pin);
42 dev->duty_fp = open(bu, O_RDWR);
43 if (dev->duty_fp == -1) {
50 mraa_pwm_write_period(mraa_pwm_context dev, int period)
52 if (advance_func->pwm_period_replace != NULL)
53 return advance_func->pwm_period_replace(dev,period);
56 snprintf(bu,MAX_SIZE ,"/sys/class/pwm/pwmchip%d/pwm%d/period", dev->chipid, dev->pin);
58 int period_f = open(bu, O_RDWR);
60 syslog(LOG_ERR, "pwm: Failed to open period for writing");
61 return MRAA_ERROR_INVALID_RESOURCE;
64 int length = snprintf(out, MAX_SIZE, "%d", period);
65 if (write(period_f, out, length*sizeof(char)) == -1) {
67 return MRAA_ERROR_INVALID_RESOURCE;
75 mraa_pwm_write_duty(mraa_pwm_context dev, int duty)
77 if (dev->duty_fp == -1) {
78 if (mraa_pwm_setup_duty_fp(dev) == 1) {
79 return MRAA_ERROR_INVALID_HANDLE;
83 int length = sprintf(bu, "%d", duty);
84 if (write(dev->duty_fp, bu, length * sizeof(char)) == -1)
85 return MRAA_ERROR_INVALID_RESOURCE;
90 mraa_pwm_read_period(mraa_pwm_context dev)
93 char output[MAX_SIZE];
94 snprintf(bu,MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/period", dev->chipid, dev->pin);
96 int period_f = open(bu, O_RDWR);
98 syslog(LOG_ERR, "pwm: Failed to open period for reading");
101 off_t size = lseek(period_f, 0, SEEK_END);
102 lseek(period_f, 0, SEEK_SET);
104 ssize_t rb = read(period_f, output, size + 1);
108 syslog(LOG_ERR, "pwm: Error in reading period");
113 long int ret = strtol(output, &endptr, 10);
114 if ('\0' != *endptr && '\n' != *endptr) {
115 syslog(LOG_ERR, "pwm: Error in string conversion");
118 else if (ret > INT_MAX || ret < INT_MIN) {
119 syslog(LOG_ERR, "pwm: Number is invalid");
126 mraa_pwm_read_duty(mraa_pwm_context dev)
128 if (dev->duty_fp == -1) {
129 if (mraa_pwm_setup_duty_fp(dev) == 1) {
130 return MRAA_ERROR_INVALID_HANDLE;
133 lseek(dev->duty_fp, 0, SEEK_SET);
135 off_t size = lseek(dev->duty_fp, 0, SEEK_END);
136 lseek(dev->duty_fp, 0, SEEK_SET);
137 char output[MAX_SIZE];
138 ssize_t rb = read(dev->duty_fp, output, size+1);
140 syslog(LOG_ERR, "pwm: Error in reading duty");
145 long int ret = strtol(output, &endptr, 10);
146 if ('\0' != *endptr && '\n' != *endptr) {
147 syslog(LOG_ERR, "pwm: Error in string converstion");
150 else if (ret > INT_MAX || ret < INT_MIN) {
151 syslog(LOG_ERR, "pwm: Number is invalid");
158 mraa_pwm_init(int pin)
160 if (advance_func->pwm_init_pre != NULL) {
161 if (advance_func->pwm_init_pre(pin) != MRAA_SUCCESS)
165 syslog(LOG_ERR, "pwm: Platform Not Initialised");
168 if (plat->pins[pin].capabilites.pwm != 1) {
169 syslog(LOG_ERR, "pwm: pin not capable of pwm");
173 if (plat->pins[pin].capabilites.gpio == 1) {
174 // This deserves more investigation
175 mraa_gpio_context mux_i;
176 mux_i = mraa_gpio_init_raw(plat->pins[pin].gpio.pinmap);
178 syslog(LOG_ERR, "pwm: error in gpio->pwm transition");
181 if (mraa_gpio_dir(mux_i, MRAA_GPIO_OUT) != MRAA_SUCCESS) {
182 syslog(LOG_ERR, "pwm: error in gpio->pwm transition");
185 if (mraa_gpio_write(mux_i, 1) != MRAA_SUCCESS) {
186 syslog(LOG_ERR, "pwm: error in gpio->pwm transition");
189 if (mraa_gpio_close(mux_i) != MRAA_SUCCESS) {
190 syslog(LOG_ERR, "pwm: error in gpio->pwm transition");
195 if (plat->pins[pin].pwm.mux_total > 0) {
196 if (mraa_setup_mux_mapped(plat->pins[pin].pwm) != MRAA_SUCCESS) {
197 syslog(LOG_ERR, "pwm: Failed to set-up multiplexer");
202 int chip = plat->pins[pin].pwm.parent_id;
203 int pinn = plat->pins[pin].pwm.pinmap;
205 if (advance_func->pwm_init_post != NULL) {
206 mraa_pwm_context pret = mraa_pwm_init_raw(chip,pinn);
207 mraa_result_t ret = advance_func->pwm_init_post(pret);
208 if (ret != MRAA_SUCCESS) {
214 return mraa_pwm_init_raw(chip,pinn);
218 mraa_pwm_init_raw(int chipin, int pin)
220 mraa_pwm_context dev = (mraa_pwm_context) malloc(sizeof(struct _pwm));
224 dev->chipid = chipin;
227 char directory[MAX_SIZE];
228 snprintf(directory, MAX_SIZE, SYSFS_PWM "/pwmchip%d/pwm%d", dev->chipid, dev->pin);
230 if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
231 syslog(LOG_NOTICE, "pwm: Pin already exported, continuing");
232 dev->owner = 0; // Not Owner
234 char buffer[MAX_SIZE];
235 snprintf(buffer, MAX_SIZE, "/sys/class/pwm/pwmchip%d/export", dev->chipid);
236 int export_f = open(buffer, O_WRONLY);
237 if (export_f == -1) {
238 syslog(LOG_ERR, "pwm: Failed to open export for writing");
244 int size = snprintf(out, MAX_SIZE, "%d", dev->pin);
245 if (write(export_f, out, size*sizeof(char)) == -1) {
246 syslog(LOG_WARNING, "pwm: Failed to write to export! Potentially already enabled");
252 mraa_pwm_period_us(dev, plat->pwm_default_period);
255 mraa_pwm_setup_duty_fp(dev);
260 mraa_pwm_write(mraa_pwm_context dev, float percentage)
262 if (percentage >= 1.0f) {
263 return mraa_pwm_write_duty(dev, mraa_pwm_read_period(dev));
265 return mraa_pwm_write_duty(dev, percentage * mraa_pwm_read_period(dev));
269 mraa_pwm_read(mraa_pwm_context dev)
271 int period = mraa_pwm_read_period(dev);
273 return (mraa_pwm_read_duty(dev) / (float) period);
279 mraa_pwm_period(mraa_pwm_context dev, float seconds)
281 return mraa_pwm_period_ms(dev, seconds*1000);
285 mraa_pwm_period_ms(mraa_pwm_context dev, int ms)
287 return mraa_pwm_period_us(dev, ms*1000);
291 mraa_pwm_period_us(mraa_pwm_context dev, int us)
293 if (us < plat->pwm_min_period ||
294 us > plat->pwm_max_period) {
295 syslog(LOG_ERR, "pwm: period value outside platform range");
296 return MRAA_ERROR_INVALID_PARAMETER;
298 return mraa_pwm_write_period(dev, us*1000);
302 mraa_pwm_pulsewidth(mraa_pwm_context dev, float seconds)
304 return mraa_pwm_pulsewidth_ms(dev, seconds*1000);
308 mraa_pwm_pulsewidth_ms(mraa_pwm_context dev, int ms)
310 return mraa_pwm_pulsewidth_us(dev, ms*1000);
314 mraa_pwm_pulsewidth_us(mraa_pwm_context dev, int us)
316 return mraa_pwm_write_duty(dev, us*1000);
320 mraa_pwm_enable(mraa_pwm_context dev, int enable)
329 snprintf(bu,MAX_SIZE, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);
331 int enable_f = open(bu, O_RDWR);
333 if (enable_f == -1) {
334 syslog(LOG_ERR, "pwm: Failed to open enable for writing");
335 return MRAA_ERROR_INVALID_RESOURCE;
338 int size = snprintf(out, sizeof(out), "%d", enable);
339 if (write(enable_f, out, size * sizeof(char)) == -1) {
340 syslog(LOG_ERR, "pwm: Failed to write to enable");
342 return MRAA_ERROR_INVALID_RESOURCE;
349 mraa_pwm_unexport_force(mraa_pwm_context dev)
351 char filepath[MAX_SIZE];
352 snprintf(filepath, MAX_SIZE, "/sys/class/pwm/pwmchip%d/unexport", dev->chipid);
354 int unexport_f = open(filepath, O_WRONLY);
355 if (unexport_f == -1) {
356 syslog(LOG_ERR, "pwm: Failed to open unexport for writing");
357 return MRAA_ERROR_INVALID_RESOURCE;
361 int size = snprintf(out, MAX_SIZE, "%d", dev->pin);
362 if (write(unexport_f, out, size*sizeof(char)) == -1) {
363 syslog(LOG_ERR, "pwm: Failed to write to unexport");
365 return MRAA_ERROR_INVALID_RESOURCE;
373 mraa_pwm_unexport(mraa_pwm_context dev)
375 mraa_pwm_enable(dev, 0);
377 return mraa_pwm_unexport_force(dev);
379 return MRAA_ERROR_INVALID_RESOURCE;
383 mraa_pwm_close(mraa_pwm_context dev)
385 mraa_pwm_unexport(dev);
391 mraa_pwm_owner(mraa_pwm_context dev, mraa_boolean_t owner_new)
394 return MRAA_ERROR_INVALID_RESOURCE;
395 dev->owner = owner_new;
400 mraa_pwm_config_ms(mraa_pwm_context dev, int ms ,float ms_float)
402 int old_dutycycle, old_period, status;
403 old_dutycycle = mraa_pwm_read_duty(dev);
404 old_period = mraa_pwm_read_period(dev);
405 status = mraa_pwm_period_us(dev, ms*1000);
406 if (status != MRAA_SUCCESS) {
407 mraa_pwm_write_duty(dev, old_dutycycle);
410 status = mraa_pwm_write_duty(dev, 0);
411 if (status != MRAA_SUCCESS) {
414 status = mraa_pwm_pulsewidth_us(dev, ms_float*1000);
415 if (status != MRAA_SUCCESS) {
416 mraa_pwm_write_duty(dev, old_dutycycle);
417 mraa_pwm_write_period(dev, old_period);
424 mraa_pwm_config_percent(mraa_pwm_context dev, int ms ,float percentage)
426 int old_dutycycle, old_period, status;
427 old_dutycycle = mraa_pwm_read_duty(dev);
428 old_period = mraa_pwm_read_period(dev);
429 status = mraa_pwm_period_us(dev, ms*1000);
430 if (status != MRAA_SUCCESS) {
431 mraa_pwm_write_duty(dev, old_dutycycle);
434 status = mraa_pwm_write_duty(dev, 0);
435 if (status != MRAA_SUCCESS) {
438 status = mraa_pwm_pulsewidth_us(dev, (ms*1000)*percentage);
439 if (status != MRAA_SUCCESS) {
440 mraa_pwm_write_duty(dev, old_dutycycle);
441 mraa_pwm_write_period(dev, old_period);