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gpio: get file handle if none exists

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Signed-off-by: Thomas Ingleby <thomas.c.ingleby@intel.com>
This commit is contained in:
Thomas Ingleby
2014-04-11 13:33:46 +01:00
parent aa2ed728be
commit 6d13a41c96
1 changed files with 23 additions and 5 deletions
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28
src/gpio/gpio.c
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@@ -34,6 +34,9 @@
extern "C" { extern "C" {
#endif #endif
int
gpio_get_valfp(gpio_t *gpio);
void void
gpio_init(gpio_t *gpio, int pin) { gpio_init(gpio_t *gpio, int pin) {
FILE *export_f; FILE *export_f;
@@ -43,10 +46,6 @@ gpio_init(gpio_t *gpio, int pin) {
} else { } else {
fprintf(export_f, "%d", pin); fprintf(export_f, "%d", pin);
fclose(export_f); fclose(export_f);
char bu[64];
sprintf(bu, "/sys/class/gpio/gpio%d/value", pin);
gpio->value_fp = fopen(bu, "r+b");
} }
gpio->pin = pin; gpio->pin = pin;
} }
@@ -80,6 +79,9 @@ gpio_dir(gpio_t *gpio, gpio_dir_t dir) {
int int
gpio_read(gpio_t *gpio) { gpio_read(gpio_t *gpio) {
if(gpio->value_fp == NULL) {
gpio_get_valfp(gpio);
}
fseek(gpio->value_fp, SEEK_SET, 0); fseek(gpio->value_fp, SEEK_SET, 0);
char buffer[2]; char buffer[2];
fread(buffer, 2, 1, gpio->value_fp); fread(buffer, 2, 1, gpio->value_fp);
@@ -87,7 +89,10 @@ gpio_read(gpio_t *gpio) {
} }
void void
gpio_write(gpio_t *gpio, int value){ gpio_write(gpio_t *gpio, int value) {
if(gpio->value_fp == NULL) {
gpio_get_valfp(gpio);
}
fseek(gpio->value_fp, SEEK_SET, 0); fseek(gpio->value_fp, SEEK_SET, 0);
fprintf(gpio->value_fp, "%d", value); fprintf(gpio->value_fp, "%d", value);
} }
@@ -97,6 +102,19 @@ gpio_close(gpio_t *gpio) {
} }
int
gpio_get_valfp(gpio_t *gpio) {
char bu[64];
sprintf(bu, "/sys/class/gpio/gpio%d/value", gpio->pin);
if((gpio->value_fp = fopen(bu, "r+b")) == NULL) {
return 1;
} else {
return 0;
}
return 1;
}
#ifdef __cplusplus #ifdef __cplusplus
} }
#endif #endif