2 * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
3 * Author: Brendan Le Foll <brendan.le.foll@intel.com>
4 * Copyright (c) 2014, 2015 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.
26 #include "mraa_internal.h"
38 #define SYSFS_CLASS_GPIO "/sys/class/gpio"
43 mraa_gpio_get_valfp(mraa_gpio_context dev)
46 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
47 dev->value_fp = open(bu, O_RDWR);
48 if (dev->value_fp == -1) {
49 return MRAA_ERROR_INVALID_RESOURCE;
55 static mraa_gpio_context
56 mraa_gpio_init_internal(mraa_adv_func_t* func_table, int pin)
61 mraa_result_t status = MRAA_SUCCESS;
65 mraa_gpio_context dev = (mraa_gpio_context) calloc(1, sizeof(struct _gpio));
67 syslog(LOG_CRIT, "gpio: Failed to allocate memory for context");
71 dev->advance_func = func_table;
74 if (IS_FUNC_DEFINED(dev, gpio_init_internal_replace)) {
75 status = dev->advance_func->gpio_init_internal_replace(pin);
76 if (status == MRAA_SUCCESS)
79 goto init_internal_cleanup;
82 if (IS_FUNC_DEFINED(dev, gpio_init_pre)) {
83 status = dev->advance_func->gpio_init_pre(pin);
84 if (status != MRAA_SUCCESS)
85 goto init_internal_cleanup;
89 dev->isr_value_fp = -1;
90 dev->isr_thread_terminating = 0;
93 // then check to make sure the pin is exported.
94 char directory[MAX_SIZE];
95 snprintf(directory, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/", dev->pin);
97 if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
98 dev->owner = 0; // Not Owner
100 int export = open(SYSFS_CLASS_GPIO "/export", O_WRONLY);
102 syslog(LOG_ERR, "gpio: Failed to open export for writing");
103 status = MRAA_ERROR_NO_RESOURCES;
104 goto init_internal_cleanup;
106 length = snprintf(bu, sizeof(bu), "%d", dev->pin);
107 if (write(export, bu, length * sizeof(char)) == -1) {
108 syslog(LOG_ERR, "gpio: Failed to write %d to export", dev->pin);
110 status = MRAA_ERROR_NO_RESOURCES;
111 goto init_internal_cleanup;
117 init_internal_cleanup:
118 if (status != MRAA_SUCCESS) {
127 mraa_gpio_init(int pin)
129 mraa_board_t* board = plat;
131 syslog(LOG_ERR, "gpio: platform not initialised");
135 if (mraa_is_sub_platform_id(pin)) {
136 syslog(LOG_NOTICE, "gpio: Using sub platform");
137 board = board->sub_platform;
139 syslog(LOG_ERR, "gpio: Sub platform Not Initialised");
142 pin = mraa_get_sub_platform_index(pin);
145 if (pin < 0 || pin > board->phy_pin_count) {
146 syslog(LOG_ERR, "gpio: pin %i beyond platform definition", pin);
149 if (board->pins[pin].capabilites.gpio != 1) {
150 syslog(LOG_ERR, "gpio: pin %i not capable of gpio", pin);
153 if (board->pins[pin].gpio.mux_total > 0) {
154 if (mraa_setup_mux_mapped(board->pins[pin].gpio) != MRAA_SUCCESS) {
155 syslog(LOG_ERR, "gpio: unable to setup muxes");
160 mraa_gpio_context r = mraa_gpio_init_internal(board->adv_func, board->pins[pin].gpio.pinmap);
162 syslog(LOG_CRIT, "gpio: mraa_gpio_init_raw(%d) returned error", pin);
167 if (IS_FUNC_DEFINED(r, gpio_init_post)) {
168 mraa_result_t ret = r->advance_func->gpio_init_post(r);
169 if (ret != MRAA_SUCCESS) {
178 mraa_gpio_init_raw(int pin)
180 return mraa_gpio_init_internal(plat == NULL ? NULL : plat->adv_func , pin);
185 mraa_gpio_wait_interrupt(int fd)
191 return MRAA_ERROR_INVALID_RESOURCE;
194 // setup poll on POLLPRI
196 pfd.events = POLLPRI;
198 // do an initial read to clear interrupt
199 lseek(fd, 0, SEEK_SET);
202 // Wait for it forever or until pthread_cancel
203 // poll is a cancelable point like sleep()
204 int x = poll(&pfd, 1, -1);
206 // do a final read to clear interrupt
213 mraa_gpio_interrupt_handler(void* arg)
215 mraa_gpio_context dev = (mraa_gpio_context) arg;
216 if (IS_FUNC_DEFINED(dev, gpio_interrupt_handler_replace))
217 return dev->advance_func->gpio_interrupt_handler_replace(dev);
221 // open gpio value with open(3)
223 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
224 int fp = open(bu, O_RDONLY);
226 syslog(LOG_ERR, "gpio: failed to open gpio%d/value", dev->pin);
229 dev->isr_value_fp = fp;
232 ret = mraa_gpio_wait_interrupt(dev->isr_value_fp);
233 if (ret == MRAA_SUCCESS && !dev->isr_thread_terminating) {
234 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
236 // In order to call a python object (all python functions are objects) we
237 // need to aquire the GIL (Global Interpreter Lock). This may not always be
238 // necessary but especially if doing IO (like print()) python will segfault
239 // if we do not hold a lock on the GIL
240 PyGILState_STATE gilstate = PyGILState_Ensure();
243 arglist = Py_BuildValue("(O)", dev->isr_args);
244 if (arglist == NULL) {
245 syslog(LOG_ERR, "gpio: Py_BuildValue NULL");
247 ret = PyEval_CallObject((PyObject*) dev->isr, arglist);
249 // code is python2 only
250 #if PY_VERSION_HEX < 0x0300000
251 syslog(LOG_ERR, "gpio: PyEval_CallObject failed");
252 PyObject *pvalue, *ptype, *ptraceback;
253 PyErr_Fetch(&pvalue, &ptype, &ptraceback);
254 syslog(LOG_ERR, "gpio: the error was %s:%s:%s",
255 PyString_AsString(PyObject_Str(pvalue)),
256 PyString_AsString(PyObject_Str(ptype)),
257 PyString_AsString(PyObject_Str(ptraceback))
261 Py_XDECREF(ptraceback);
269 PyGILState_Release(gilstate);
271 dev->isr(dev->isr_args);
273 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
275 // we must have got an error code or exit request so die nicely
276 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
277 close(dev->isr_value_fp);
278 dev->isr_value_fp = -1;
285 mraa_gpio_edge_mode(mraa_gpio_context dev, mraa_gpio_edge_t mode)
287 if (IS_FUNC_DEFINED(dev, gpio_edge_mode_replace))
288 return dev->advance_func->gpio_edge_mode_replace(dev, mode);
290 if (dev->value_fp != -1) {
291 close(dev->value_fp);
295 char filepath[MAX_SIZE];
296 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/edge", dev->pin);
298 int edge = open(filepath, O_RDWR);
300 syslog(LOG_ERR, "gpio: Failed to open edge for writing");
301 return MRAA_ERROR_INVALID_RESOURCE;
307 case MRAA_GPIO_EDGE_NONE:
308 length = snprintf(bu, sizeof(bu), "none");
310 case MRAA_GPIO_EDGE_BOTH:
311 length = snprintf(bu, sizeof(bu), "both");
313 case MRAA_GPIO_EDGE_RISING:
314 length = snprintf(bu, sizeof(bu), "rising");
316 case MRAA_GPIO_EDGE_FALLING:
317 length = snprintf(bu, sizeof(bu), "falling");
321 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
323 if (write(edge, bu, length * sizeof(char)) == -1) {
324 syslog(LOG_ERR, "gpio: Failed to write to edge");
326 return MRAA_ERROR_INVALID_RESOURCE;
334 mraa_gpio_isr(mraa_gpio_context dev, mraa_gpio_edge_t mode, void (*fptr)(void*), void* args)
336 // we only allow one isr per mraa_gpio_context
337 if (dev->thread_id != 0) {
338 return MRAA_ERROR_NO_RESOURCES;
341 if (MRAA_SUCCESS != mraa_gpio_edge_mode(dev, mode)) {
342 return MRAA_ERROR_UNSPECIFIED;
346 dev->isr_args = args;
347 pthread_create(&dev->thread_id, NULL, mraa_gpio_interrupt_handler, (void*) dev);
353 mraa_gpio_isr_exit(mraa_gpio_context dev)
355 mraa_result_t ret = MRAA_SUCCESS;
357 // wasting our time, there is no isr to exit from
358 if (dev->thread_id == 0 && dev->isr_value_fp == -1) {
361 // mark the beginning of the thread termination process for interested parties
362 dev->isr_thread_terminating = 1;
364 // stop isr being useful
365 ret = mraa_gpio_edge_mode(dev, MRAA_GPIO_EDGE_NONE);
367 if ((dev->thread_id != 0)) {
368 if ((pthread_cancel(dev->thread_id) != 0) || (pthread_join(dev->thread_id, NULL) != 0)) {
369 ret = MRAA_ERROR_INVALID_HANDLE;
373 // close the filehandle in case it's still open
374 if (dev->isr_value_fp != -1) {
375 if (close(dev->isr_value_fp) != 0) {
376 ret = MRAA_ERROR_INVALID_PARAMETER;
380 // assume our thread will exit either way we just lost it's handle
382 dev->isr_value_fp = -1;
383 dev->isr_thread_terminating = 0;
388 mraa_gpio_mode(mraa_gpio_context dev, mraa_gpio_mode_t mode)
390 if (IS_FUNC_DEFINED(dev, gpio_mode_replace))
391 return dev->advance_func->gpio_mode_replace(dev, mode);
393 if (IS_FUNC_DEFINED(dev, gpio_mode_pre)) {
394 mraa_result_t pre_ret = (dev->advance_func->gpio_mode_pre(dev, mode));
395 if (pre_ret != MRAA_SUCCESS)
399 if (dev->value_fp != -1) {
400 close(dev->value_fp);
404 char filepath[MAX_SIZE];
405 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);
407 int drive = open(filepath, O_WRONLY);
409 syslog(LOG_ERR, "gpio: Failed to open drive for writing");
410 return MRAA_ERROR_INVALID_RESOURCE;
416 case MRAA_GPIO_STRONG:
417 length = snprintf(bu, sizeof(bu), "strong");
419 case MRAA_GPIO_PULLUP:
420 length = snprintf(bu, sizeof(bu), "pullup");
422 case MRAA_GPIO_PULLDOWN:
423 length = snprintf(bu, sizeof(bu), "pulldown");
426 length = snprintf(bu, sizeof(bu), "hiz");
430 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
432 if (write(drive, bu, length * sizeof(char)) == -1) {
433 syslog(LOG_ERR, "gpio: Failed to write to drive mode");
435 return MRAA_ERROR_INVALID_RESOURCE;
439 if (IS_FUNC_DEFINED(dev, gpio_mode_post))
440 return dev->advance_func->gpio_mode_post(dev, mode);
445 mraa_gpio_dir(mraa_gpio_context dev, mraa_gpio_dir_t dir)
447 if (IS_FUNC_DEFINED(dev, gpio_dir_replace)) {
448 return dev->advance_func->gpio_dir_replace(dev, dir);
451 if (IS_FUNC_DEFINED(dev, gpio_dir_pre)) {
452 mraa_result_t pre_ret = (dev->advance_func->gpio_dir_pre(dev, dir));
453 if (pre_ret != MRAA_SUCCESS) {
459 return MRAA_ERROR_INVALID_HANDLE;
461 if (dev->value_fp != -1) {
462 close(dev->value_fp);
465 char filepath[MAX_SIZE];
466 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/direction", dev->pin);
468 int direction = open(filepath, O_RDWR);
470 if (direction == -1) {
471 // Direction Failed to Open. If HIGH or LOW was passed will try and set
472 // If not fail as usual.
474 case MRAA_GPIO_OUT_HIGH:
475 return mraa_gpio_write(dev, 1);
476 case MRAA_GPIO_OUT_LOW:
477 return mraa_gpio_write(dev, 0);
479 return MRAA_ERROR_INVALID_RESOURCE;
487 length = snprintf(bu, sizeof(bu), "out");
490 length = snprintf(bu, sizeof(bu), "in");
492 case MRAA_GPIO_OUT_HIGH:
493 length = snprintf(bu, sizeof(bu), "high");
495 case MRAA_GPIO_OUT_LOW:
496 length = snprintf(bu, sizeof(bu), "low");
500 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
503 if (write(direction, bu, length * sizeof(char)) == -1) {
505 return MRAA_ERROR_INVALID_RESOURCE;
509 if (IS_FUNC_DEFINED(dev, gpio_dir_post))
510 return dev->advance_func->gpio_dir_post(dev, dir);
515 mraa_gpio_read(mraa_gpio_context dev)
520 if (IS_FUNC_DEFINED(dev, gpio_read_replace))
521 return dev->advance_func->gpio_read_replace(dev);
523 if (dev->mmap_read != NULL)
524 return dev->mmap_read(dev);
526 if (dev->value_fp == -1) {
527 if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
528 syslog(LOG_ERR, "gpio: Failed to get value file pointer");
532 // if value_fp is new this is pointless
533 lseek(dev->value_fp, 0, SEEK_SET);
536 if (read(dev->value_fp, bu, 2 * sizeof(char)) != 2) {
537 syslog(LOG_ERR, "gpio: Failed to read a sensible value from sysfs");
540 lseek(dev->value_fp, 0, SEEK_SET);
542 return (int) strtol(bu, NULL, 10);
546 mraa_gpio_write(mraa_gpio_context dev, int value)
549 return MRAA_ERROR_INVALID_HANDLE;
551 if (dev->mmap_write != NULL)
552 return dev->mmap_write(dev, value);
554 if (IS_FUNC_DEFINED(dev, gpio_write_pre)) {
555 mraa_result_t pre_ret = (dev->advance_func->gpio_write_pre(dev, value));
556 if (pre_ret != MRAA_SUCCESS)
560 if (dev->value_fp == -1) {
561 if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
562 return MRAA_ERROR_INVALID_RESOURCE;
566 if (lseek(dev->value_fp, 0, SEEK_SET) == -1) {
567 return MRAA_ERROR_INVALID_RESOURCE;
571 int length = snprintf(bu, sizeof(bu), "%d", value);
572 if (write(dev->value_fp, bu, length * sizeof(char)) == -1) {
573 return MRAA_ERROR_INVALID_HANDLE;
576 if (IS_FUNC_DEFINED(dev, gpio_write_post))
577 return dev->advance_func->gpio_write_post(dev, value);
582 mraa_gpio_unexport_force(mraa_gpio_context dev)
584 int unexport = open(SYSFS_CLASS_GPIO "/unexport", O_WRONLY);
585 if (unexport == -1) {
586 syslog(LOG_ERR, "gpio: Failed to open unexport for writing");
587 return MRAA_ERROR_INVALID_RESOURCE;
591 int length = snprintf(bu, sizeof(bu), "%d", dev->pin);
592 if (write(unexport, bu, length * sizeof(char)) == -1) {
593 syslog(LOG_ERR, "gpio: Failed to write to unexport");
595 return MRAA_ERROR_INVALID_RESOURCE;
599 mraa_gpio_isr_exit(dev);
603 mraa_gpio_unexport(mraa_gpio_context dev)
606 return mraa_gpio_unexport_force(dev);
608 return MRAA_ERROR_INVALID_RESOURCE;
612 mraa_gpio_close(mraa_gpio_context dev)
614 mraa_result_t result = MRAA_SUCCESS;
616 if (IS_FUNC_DEFINED(dev, gpio_close_pre)) {
617 result = dev->advance_func->gpio_close_pre(dev);
620 if (dev->value_fp != -1) {
621 close(dev->value_fp);
623 mraa_gpio_unexport(dev);
629 mraa_gpio_owner(mraa_gpio_context dev, mraa_boolean_t own)
632 return MRAA_ERROR_INVALID_RESOURCE;
634 syslog(LOG_DEBUG, "gpio: Set owner to %d", (int) own);
640 mraa_gpio_use_mmaped(mraa_gpio_context dev, mraa_boolean_t mmap_en)
642 if (IS_FUNC_DEFINED(dev, gpio_mmap_setup)) {
643 return dev->advance_func->gpio_mmap_setup(dev, mmap_en);
646 syslog(LOG_ERR, "gpio: mmap not implemented on this platform");
647 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
651 mraa_gpio_get_pin(mraa_gpio_context dev)
654 syslog(LOG_ERR, "gpio: context is invalid");
661 mraa_gpio_get_pin_raw(mraa_gpio_context dev)
664 syslog(LOG_ERR, "gpio: context is invalid");