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 printf("Actually entering\n");
72 if (advance_func->gpio_init_pre(pin) != MRAA_SUCCESS)
82 mraa_gpio_context dev = (mraa_gpio_context) malloc(sizeof(struct _gpio));
83 memset(dev, 0, sizeof(struct _gpio));
85 dev->isr_value_fp = -1;
89 char directory[MAX_SIZE];
90 snprintf(directory, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/", dev->pin);
92 if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
93 //fprintf(stderr, "GPIO Pin already exporting, continuing.\n");
94 dev->owner = 0; // Not Owner
96 int export = open(SYSFS_CLASS_GPIO "/export", O_WRONLY);
98 fprintf(stderr, "Failed to open export for writing!\n");
101 length = snprintf(bu, sizeof(bu), "%d", dev->pin);
102 if (write(export, bu, length*sizeof(char)) == -1) {
103 fprintf(stderr, "Failed to write to export\n");
111 if (advance_func->gpio_init_post != NULL) {
119 mraa_gpio_write_register(mraa_gpio_context dev,int value)
121 if (advance_func->gpio_mmaped_write_replace != NULL)
122 return advance_func->gpio_mmaped_write_replace(dev,value);
123 if (advance_func->gpio_mmaped_write_pre != NULL) {
124 mraa_result_t pre_ret = (advance_func->gpio_mmaped_write_pre(dev,value));
125 if(pre_ret != MRAA_SUCCESS)
129 *((unsigned *)dev->reg) |= (1<<dev->reg_bit_pos);
132 *((unsigned *)dev->reg) &= ~(1<<dev->reg_bit_pos);
134 if (advance_func->gpio_mmaped_write_post != NULL)
135 return advance_func->gpio_mmaped_write_post(dev,value);
140 mraa_gpio_wait_interrupt(int fd)
145 // setup poll on POLLPRI
147 pfd.events = POLLPRI;
149 // do an initial read to clear interupt
153 return MRAA_ERROR_INVALID_RESOURCE;
156 // Wait for it forever or until pthread_cancel
157 // poll is a cancelable point like sleep()
158 int x = poll (&pfd, 1, -1);
160 // do a final read to clear interupt
167 mraa_gpio_interrupt_handler(void* arg)
169 mraa_gpio_context dev = (mraa_gpio_context) arg;
172 // open gpio value with open(3)
174 sprintf(bu, SYSFS_CLASS_GPIO "/gpio%d/value", dev->pin);
175 dev->isr_value_fp = open(bu, O_RDONLY);
178 ret = mraa_gpio_wait_interrupt(dev->isr_value_fp);
179 if (ret == MRAA_SUCCESS) {
180 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
182 // In order to call a python object (all python functions are objects) we
183 // need to aquire the GIL (Global Interpreter Lock). This may not always be
184 // nessecary but especially if doing IO (like print()) python will segfault
185 // if we do not hold a lock on the GIL
186 PyGILState_STATE gilstate = PyGILState_Ensure();
189 arglist = Py_BuildValue("(i)", dev->isr_args);
190 if (arglist == NULL) {
191 fprintf(stdout, "Py_BuildValue NULL\n");
193 ret = PyEval_CallObject((PyObject*)dev->isr, arglist);
195 fprintf(stdout, "PyEval_CallObject failed\n");
202 PyGILState_Release (gilstate);
204 dev->isr(dev->isr_args);
206 pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL);
208 // we must have got an error code so die nicely
209 pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, NULL);
210 close(dev->isr_value_fp);
211 dev->isr_value_fp = -1;
218 mraa_gpio_edge_mode(mraa_gpio_context dev, gpio_edge_t mode)
220 if (dev->value_fp != -1) {
221 close(dev->value_fp);
225 char filepath[MAX_SIZE];
226 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/edge", dev->pin);
228 int edge = open(filepath, O_RDWR);
230 fprintf(stderr, "Failed to open edge for writing!\n");
231 return MRAA_ERROR_INVALID_RESOURCE;
237 case MRAA_GPIO_EDGE_NONE:
238 length = snprintf(bu, sizeof(bu), "none");
240 case MRAA_GPIO_EDGE_BOTH:
241 length = snprintf(bu, sizeof(bu), "both");
243 case MRAA_GPIO_EDGE_RISING:
244 length = snprintf(bu, sizeof(bu), "rising");
246 case MRAA_GPIO_EDGE_FALLING:
247 length = snprintf(bu, sizeof(bu), "falling");
251 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
253 if (write(edge, bu, length*sizeof(char)) == -1) {
254 fprintf(stderr, "Failed to write to edge\n");
256 return MRAA_ERROR_INVALID_RESOURCE;
264 mraa_gpio_isr(mraa_gpio_context dev, gpio_edge_t mode, void (*fptr)(void *), void * args)
266 // we only allow one isr per mraa_gpio_context
267 if (dev->thread_id != 0) {
268 return MRAA_ERROR_NO_RESOURCES;
271 if (MRAA_SUCCESS != mraa_gpio_edge_mode(dev, mode)) {
272 return MRAA_ERROR_UNSPECIFIED;
276 dev->isr_args = args;
277 pthread_create (&dev->thread_id, NULL, mraa_gpio_interrupt_handler, (void *) dev);
283 mraa_gpio_isr_exit(mraa_gpio_context dev)
285 mraa_result_t ret = MRAA_SUCCESS;
287 // wasting our time, there is no isr to exit from
288 if (dev->thread_id == 0 && dev->isr_value_fp == -1) {
292 // stop isr being useful
293 ret = mraa_gpio_edge_mode(dev, MRAA_GPIO_EDGE_NONE);
295 if ((dev->thread_id != 0) &&
296 (pthread_cancel(dev->thread_id) != 0)) {
297 ret = MRAA_ERROR_INVALID_HANDLE;
300 // close the filehandle in case it's still open
301 if (dev->isr_value_fp != -1) {
302 if (close(dev->isr_value_fp) != 0) {
303 ret = MRAA_ERROR_INVALID_PARAMETER;
308 // Dereference our Python call back function
312 // assume our thread will exit either way we just lost it's handle
314 dev->isr_value_fp = -1;
319 mraa_gpio_mode(mraa_gpio_context dev, gpio_mode_t mode)
321 if (advance_func->gpio_mode_replace != NULL)
322 return advance_func->gpio_mode_replace(dev,mode);
324 if (advance_func->gpio_mode_pre != NULL) {
325 mraa_result_t pre_ret = (advance_func->gpio_mode_pre(dev,mode));
326 if(pre_ret != MRAA_SUCCESS)
330 if (dev->value_fp != -1) {
331 close(dev->value_fp);
335 char filepath[MAX_SIZE];
336 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/drive", dev->pin);
338 int drive = open(filepath, O_WRONLY);
340 fprintf(stderr, "Failed to open drive for writing!\n");
341 return MRAA_ERROR_INVALID_RESOURCE;
347 case MRAA_GPIO_STRONG:
348 length = snprintf(bu, sizeof(bu), "strong");
350 case MRAA_GPIO_PULLUP:
351 length = snprintf(bu, sizeof(bu), "pullup");
353 case MRAA_GPIO_PULLDOWN:
354 length = snprintf(bu, sizeof(bu), "pulldown");
357 length = snprintf(bu, sizeof(bu), "hiz");
361 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
363 if (write(drive, bu, length*sizeof(char)) == -1) {
364 fprintf(stderr, "Failed to write to drive mode!\n");
366 return MRAA_ERROR_INVALID_RESOURCE;
371 if (advance_func->gpio_mode_post != NULL)
372 return advance_func->gpio_mode_post(dev,mode);
377 mraa_gpio_dir(mraa_gpio_context dev, gpio_dir_t dir)
379 if (advance_func->gpio_dir_replace != NULL)
380 return advance_func->gpio_dir_replace(dev,dir);
381 if (advance_func->gpio_dir_pre != NULL) {
382 mraa_result_t pre_ret = (advance_func->gpio_dir_pre(dev,dir));
383 if(pre_ret != MRAA_SUCCESS)
388 return MRAA_ERROR_INVALID_HANDLE;
390 if (dev->value_fp != -1) {
391 close(dev->value_fp);
394 char filepath[MAX_SIZE];
395 snprintf(filepath, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/direction", dev->pin);
397 int direction = open(filepath, O_RDWR);
399 if (direction == -1) {
400 return MRAA_ERROR_INVALID_RESOURCE;
408 length = snprintf(bu, sizeof(bu), "out");
412 length = snprintf(bu, sizeof(bu), "in");
416 return MRAA_ERROR_FEATURE_NOT_IMPLEMENTED;
419 if (dev->phy_pin >= 0) {
420 mraa_result_t swap_res = mraa_swap_complex_gpio(dev->phy_pin, out_switch);
421 if (swap_res != MRAA_SUCCESS)
425 if (write(direction, bu, length*sizeof(char)) == -1) {
427 return MRAA_ERROR_INVALID_RESOURCE;
431 if (advance_func->gpio_dir_post != NULL)
432 return advance_func->gpio_dir_post(dev,dir);
437 mraa_gpio_read(mraa_gpio_context dev)
439 if (dev->value_fp == -1) {
440 if (mraa_gpio_get_valfp(dev) != MRAA_SUCCESS) {
441 fprintf(stderr, "Failed to get value file pointer\n");
445 // if value_fp is new this is pointless
446 lseek(dev->value_fp, 0, SEEK_SET);
449 if (read(dev->value_fp, bu, 2*sizeof(char)) != 2) {
450 fprintf(stderr, "Failed to read a sensible value from sysfs");
452 lseek(dev->value_fp, 0, SEEK_SET);
453 int ret = strtol(bu, NULL, 10);
460 mraa_gpio_write(mraa_gpio_context dev, int value)
463 return mraa_gpio_write_register(dev,value);
465 if (advance_func->gpio_write_pre != NULL) {
466 mraa_result_t pre_ret = (advance_func->gpio_write_pre(dev,value));
467 if(pre_ret != MRAA_SUCCESS)
471 if (dev->value_fp == -1) {
472 mraa_gpio_get_valfp(dev);
474 if (lseek(dev->value_fp, 0, SEEK_SET) == -1) {
475 return MRAA_ERROR_INVALID_RESOURCE;
479 int length = snprintf(bu, sizeof(bu), "%d", value);
480 if (write(dev->value_fp, bu, length*sizeof(char)) == -1) {
481 return MRAA_ERROR_INVALID_HANDLE;
484 if (advance_func->gpio_write_post != NULL)
485 return advance_func->gpio_write_post(dev,value);
490 mraa_gpio_unexport_force(mraa_gpio_context dev)
492 int unexport = open(SYSFS_CLASS_GPIO "/unexport", O_WRONLY);
493 if (unexport == -1) {
494 fprintf(stderr, "Failed to open unexport for writing!\n");
495 return MRAA_ERROR_INVALID_RESOURCE;
499 int length = snprintf(bu, sizeof(bu), "%d", dev->pin);
500 if (write(unexport, bu, length*sizeof(char)) == -1) {
501 fprintf(stderr, "Failed to write to unexport\n");
503 return MRAA_ERROR_INVALID_RESOURCE;
507 mraa_gpio_isr_exit(dev);
511 mraa_gpio_unexport(mraa_gpio_context dev)
514 return mraa_gpio_unexport_force(dev);
516 return MRAA_ERROR_INVALID_RESOURCE;
520 mraa_gpio_close(mraa_gpio_context dev)
522 if (dev->value_fp != -1) {
523 close(dev->value_fp);
525 mraa_gpio_unexport(dev);
531 mraa_gpio_owner(mraa_gpio_context dev, mraa_boolean_t own)
534 return MRAA_ERROR_INVALID_RESOURCE;
540 mraa_gpio_use_mmaped(mraa_gpio_context dev, mraa_boolean_t mmap_en)
543 return MRAA_ERROR_INVALID_RESOURCE;
546 if (mraa_pin_mode_test(dev->phy_pin, MRAA_PIN_FAST_GPIO) == 0)
547 return MRAA_ERROR_NO_RESOURCES;
549 mraa_mmap_pin_t *mmp = mraa_setup_mmap_gpio(dev->phy_pin);
551 return MRAA_ERROR_INVALID_RESOURCE;
554 if (dev->mmap == 0) {
555 close(dev->value_fp);
557 fd = open(mmp->mem_dev, O_RDWR);
559 fprintf(stderr, "Unable to open memory device\n");
560 return MRAA_ERROR_INVALID_RESOURCE;
562 dev->reg_sz = mmp->mem_sz;
563 dev->reg = mmap(NULL, dev->reg_sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
564 dev->reg_bit_pos = mmp->bit_pos;
568 return MRAA_ERROR_INVALID_PARAMETER;
572 if (dev ->mmap == 1) {
573 munmap(dev->reg, dev->reg_sz);
576 return MRAA_ERROR_INVALID_PARAMETER;