2 * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
3 * Author: Brendan Le Foll <brendan.le.foll@intel.com>
4 * Copyright (c) 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.
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;
56 mraa_gpio_init(int pin)
58 int pinm = mraa_setup_gpio(pin);
62 mraa_gpio_context r = mraa_gpio_init_raw(pinm);
68 mraa_gpio_init_raw(int pin)
70 if (advance_func->gpio_init_pre != NULL) {
71 if (advance_func->gpio_init_pre(pin) != MRAA_SUCCESS)
81 mraa_gpio_context dev = (mraa_gpio_context) malloc(sizeof(struct _gpio));
82 memset(dev, 0, sizeof(struct _gpio));
84 dev->isr_value_fp = -1;
88 char directory[MAX_SIZE];
89 snprintf(directory, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/", dev->pin);
91 if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
92 dev->owner = 0; // Not Owner
94 int export = open(SYSFS_CLASS_GPIO "/export", O_WRONLY);
96 fprintf(stderr, "Failed to open export for writing!\n");
99 length = snprintf(bu, sizeof(bu), "%d", dev->pin);
100 if (write(export, bu, length*sizeof(char)) == -1) {
101 fprintf(stderr, "Failed to write to export\n");
109 if (advance_func->gpio_init_post != NULL) {
110 mraa_result_t ret = advance_func->gpio_init_post(dev);
111 if (ret != MRAA_SUCCESS) {
120 mraa_gpio_write_register(mraa_gpio_context dev,int value)
122 if (advance_func->gpio_mmaped_write_replace != NULL)
123 return advance_func->gpio_mmaped_write_replace(dev,value);
124 if (advance_func->gpio_mmaped_write_pre != NULL) {
125 mraa_result_t pre_ret = (advance_func->gpio_mmaped_write_pre(dev,value));
126 if(pre_ret != MRAA_SUCCESS)
130 *((unsigned *)dev->reg) |= (1<<dev->reg_bit_pos);
133 *((unsigned *)dev->reg) &= ~(1<<dev->reg_bit_pos);
135 if (advance_func->gpio_mmaped_write_post != NULL)
136 return advance_func->gpio_mmaped_write_post(dev,value);
141 mraa_gpio_wait_interrupt(int fd)
146 // setup poll on POLLPRI
148 pfd.events = POLLPRI;
150 // do an initial read to clear interupt
154 return MRAA_ERROR_INVALID_RESOURCE;
157 // Wait for it forever or until pthread_cancel
158 // poll is a cancelable point like sleep()
159 int x = poll (&pfd, 1, -1);
161 // do a final read to clear interupt
168 mraa_gpio_interrupt_handler(void* arg)
170 mraa_gpio_context dev = (mraa_gpio_context) arg;
173 // open gpio value with open(3)
175 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
176 dev->isr_value_fp = open(bu, O_RDONLY);
179 ret = mraa_gpio_wait_interrupt(dev->isr_value_fp);
180 if (ret == MRAA_SUCCESS) {
181 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
183 // In order to call a python object (all python functions are objects) we
184 // need to aquire the GIL (Global Interpreter Lock). This may not always be
185 // nessecary but especially if doing IO (like print()) python will segfault
186 // if we do not hold a lock on the GIL
187 PyGILState_STATE gilstate = PyGILState_Ensure();
190 arglist = Py_BuildValue("(i)", dev->isr_args);
191 if (arglist == NULL) {
192 fprintf(stdout, "Py_BuildValue NULL\n");
194 ret = PyEval_CallObject((PyObject*)dev->isr, arglist);
196 fprintf(stdout, "PyEval_CallObject failed\n");
203 PyGILState_Release (gilstate);
205 dev->isr(dev->isr_args);
207 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
209 // we must have got an error code so die nicely
210 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
211 close(dev->isr_value_fp);
212 dev->isr_value_fp = -1;
219 mraa_gpio_edge_mode(mraa_gpio_context dev, gpio_edge_t mode)
221 if (dev->value_fp != -1) {
222 close(dev->value_fp);
226 char filepath[MAX_SIZE];
227 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/edge", dev->pin);
229 int edge = open(filepath, O_RDWR);
231 fprintf(stderr, "Failed to open edge for writing!\n");
232 return MRAA_ERROR_INVALID_RESOURCE;
238 case MRAA_GPIO_EDGE_NONE:
239 length = snprintf(bu, sizeof(bu), "none");
241 case MRAA_GPIO_EDGE_BOTH:
242 length = snprintf(bu, sizeof(bu), "both");
244 case MRAA_GPIO_EDGE_RISING:
245 length = snprintf(bu, sizeof(bu), "rising");
247 case MRAA_GPIO_EDGE_FALLING:
248 length = snprintf(bu, sizeof(bu), "falling");
252 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
254 if (write(edge, bu, length*sizeof(char)) == -1) {
255 fprintf(stderr, "Failed to write to edge\n");
257 return MRAA_ERROR_INVALID_RESOURCE;
265 mraa_gpio_isr(mraa_gpio_context dev, gpio_edge_t mode, void (*fptr)(void *), void * args)
267 // we only allow one isr per mraa_gpio_context
268 if (dev->thread_id != 0) {
269 return MRAA_ERROR_NO_RESOURCES;
272 if (MRAA_SUCCESS != mraa_gpio_edge_mode(dev, mode)) {
273 return MRAA_ERROR_UNSPECIFIED;
277 dev->isr_args = args;
278 pthread_create (&dev->thread_id, NULL, mraa_gpio_interrupt_handler, (void *) dev);
284 mraa_gpio_isr_exit(mraa_gpio_context dev)
286 mraa_result_t ret = MRAA_SUCCESS;
288 // wasting our time, there is no isr to exit from
289 if (dev->thread_id == 0 && dev->isr_value_fp == -1) {
293 // stop isr being useful
294 ret = mraa_gpio_edge_mode(dev, MRAA_GPIO_EDGE_NONE);
296 if ((dev->thread_id != 0) &&
297 (pthread_cancel(dev->thread_id) != 0)) {
298 ret = MRAA_ERROR_INVALID_HANDLE;
301 // close the filehandle in case it's still open
302 if (dev->isr_value_fp != -1) {
303 if (close(dev->isr_value_fp) != 0) {
304 ret = MRAA_ERROR_INVALID_PARAMETER;
309 // Dereference our Python call back function
313 // assume our thread will exit either way we just lost it's handle
315 dev->isr_value_fp = -1;
320 mraa_gpio_mode(mraa_gpio_context dev, gpio_mode_t mode)
322 if (advance_func->gpio_mode_replace != NULL)
323 return advance_func->gpio_mode_replace(dev,mode);
325 if (advance_func->gpio_mode_pre != NULL) {
326 mraa_result_t pre_ret = (advance_func->gpio_mode_pre(dev,mode));
327 if(pre_ret != MRAA_SUCCESS)
331 if (dev->value_fp != -1) {
332 close(dev->value_fp);
336 char filepath[MAX_SIZE];
337 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);
339 int drive = open(filepath, O_WRONLY);
341 fprintf(stderr, "Failed to open drive for writing!\n");
342 return MRAA_ERROR_INVALID_RESOURCE;
348 case MRAA_GPIO_STRONG:
349 length = snprintf(bu, sizeof(bu), "strong");
351 case MRAA_GPIO_PULLUP:
352 length = snprintf(bu, sizeof(bu), "pullup");
354 case MRAA_GPIO_PULLDOWN:
355 length = snprintf(bu, sizeof(bu), "pulldown");
358 length = snprintf(bu, sizeof(bu), "hiz");
362 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
364 if (write(drive, bu, length*sizeof(char)) == -1) {
365 fprintf(stderr, "Failed to write to drive mode!\n");
367 return MRAA_ERROR_INVALID_RESOURCE;
372 if (advance_func->gpio_mode_post != NULL)
373 return advance_func->gpio_mode_post(dev,mode);
378 mraa_gpio_dir(mraa_gpio_context dev, gpio_dir_t dir)
380 if (advance_func->gpio_dir_replace != NULL)
381 return advance_func->gpio_dir_replace(dev,dir);
382 if (advance_func->gpio_dir_pre != NULL) {
383 mraa_result_t pre_ret = (advance_func->gpio_dir_pre(dev,dir));
384 if(pre_ret != MRAA_SUCCESS)
389 return MRAA_ERROR_INVALID_HANDLE;
391 if (dev->value_fp != -1) {
392 close(dev->value_fp);
395 char filepath[MAX_SIZE];
396 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/direction", dev->pin);
398 int direction = open(filepath, O_RDWR);
400 if (direction == -1) {
401 return MRAA_ERROR_INVALID_RESOURCE;
408 length = snprintf(bu, sizeof(bu), "out");
411 length = snprintf(bu, sizeof(bu), "in");
415 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
418 if (write(direction, bu, length*sizeof(char)) == -1) {
420 return MRAA_ERROR_INVALID_RESOURCE;
424 if (advance_func->gpio_dir_post != NULL)
425 return advance_func->gpio_dir_post(dev,dir);
430 mraa_gpio_read(mraa_gpio_context dev)
432 if (dev->value_fp == -1) {
433 if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
434 fprintf(stderr, "Failed to get value file pointer\n");
438 // if value_fp is new this is pointless
439 lseek(dev->value_fp, 0, SEEK_SET);
442 if (read(dev->value_fp, bu, 2*sizeof(char)) != 2) {
443 fprintf(stderr, "Failed to read a sensible value from sysfs");
445 lseek(dev->value_fp, 0, SEEK_SET);
446 int ret = strtol(bu, NULL, 10);
453 mraa_gpio_write(mraa_gpio_context dev, int value)
456 return mraa_gpio_write_register(dev,value);
458 if (advance_func->gpio_write_pre != NULL) {
459 mraa_result_t pre_ret = (advance_func->gpio_write_pre(dev,value));
460 if(pre_ret != MRAA_SUCCESS)
464 if (dev->value_fp == -1) {
465 mraa_gpio_get_valfp(dev);
467 if (lseek(dev->value_fp, 0, SEEK_SET) == -1) {
468 return MRAA_ERROR_INVALID_RESOURCE;
472 int length = snprintf(bu, sizeof(bu), "%d", value);
473 if (write(dev->value_fp, bu, length*sizeof(char)) == -1) {
474 return MRAA_ERROR_INVALID_HANDLE;
477 if (advance_func->gpio_write_post != NULL)
478 return advance_func->gpio_write_post(dev,value);
483 mraa_gpio_unexport_force(mraa_gpio_context dev)
485 int unexport = open(SYSFS_CLASS_GPIO "/unexport", O_WRONLY);
486 if (unexport == -1) {
487 fprintf(stderr, "Failed to open unexport for writing!\n");
488 return MRAA_ERROR_INVALID_RESOURCE;
492 int length = snprintf(bu, sizeof(bu), "%d", dev->pin);
493 if (write(unexport, bu, length*sizeof(char)) == -1) {
494 fprintf(stderr, "Failed to write to unexport\n");
496 return MRAA_ERROR_INVALID_RESOURCE;
500 mraa_gpio_isr_exit(dev);
504 mraa_gpio_unexport(mraa_gpio_context dev)
507 return mraa_gpio_unexport_force(dev);
509 return MRAA_ERROR_INVALID_RESOURCE;
513 mraa_gpio_close(mraa_gpio_context dev)
515 if (dev->value_fp != -1) {
516 close(dev->value_fp);
518 mraa_gpio_unexport(dev);
524 mraa_gpio_owner(mraa_gpio_context dev, mraa_boolean_t own)
527 return MRAA_ERROR_INVALID_RESOURCE;
533 mraa_gpio_use_mmaped(mraa_gpio_context dev, mraa_boolean_t mmap_en)
536 return MRAA_ERROR_INVALID_RESOURCE;
539 if (mraa_pin_mode_test(dev->phy_pin, MRAA_PIN_FAST_GPIO) == 0)
540 return MRAA_ERROR_NO_RESOURCES;
542 mraa_mmap_pin_t *mmp = mraa_setup_mmap_gpio(dev->phy_pin);
544 return MRAA_ERROR_INVALID_RESOURCE;
547 if (dev->mmap == 0) {
548 close(dev->value_fp);
550 fd = open(mmp->mem_dev, O_RDWR);
552 fprintf(stderr, "Unable to open memory device\n");
553 return MRAA_ERROR_INVALID_RESOURCE;
555 dev->reg_sz = mmp->mem_sz;
556 dev->reg = mmap(NULL, dev->reg_sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
557 dev->reg_bit_pos = mmp->bit_pos;
562 return MRAA_ERROR_INVALID_PARAMETER;
566 if (dev ->mmap == 1) {
567 munmap(dev->reg, dev->reg_sz);
570 return MRAA_ERROR_INVALID_PARAMETER;