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mmap: added mmap io to gpio

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* added function to gpio to use mmap
* changed board definition format around mmap io (fast-gpio)
* Intel Galileo Rev D updated to follow changed definitions

* Example performing mmap io to pin 2 added.

Signed-off-by: Thomas Ingleby <thomas.c.ingleby@intel.com>
This commit is contained in:
Thomas Ingleby
2014-05-29 16:30:07 +01:00
parent b9352a9e8c
commit 7af6a96a13
8 changed files with 182 additions and 11 deletions
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69
src/gpio/gpio.c
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@@ -33,6 +33,7 @@
#include <pthread.h>
#include <signal.h>
#include <sys/stat.h>
#include <sys/mman.h>
#define SYSFS_CLASS_GPIO "/sys/class/gpio"
#define MAX_SIZE 64
@@ -45,11 +46,16 @@
struct _gpio {
/*@{*/
int pin; /**< the pin number, as known to the os. */
int phy_pin; /**< pin passed to clean init. -1 none and raw*/
int value_fp; /**< the file pointer to the value of the gpio */
void (* isr)(); /**< the interupt service request */
pthread_t thread_id; /**< the isr handler thread id */
int isr_value_fp; /**< the isr file pointer on the value */
maa_boolean_t owner; /**< If this context originally exported the pin */
maa_boolean_t mmap;
void *reg;
unsigned int reg_sz;
unsigned int reg_bit_pos;
/*@}*/
};
@@ -73,7 +79,9 @@ maa_gpio_init(int pin)
if (pinm < 0)
return NULL;
return maa_gpio_init_raw(pinm);
maa_gpio_context r = maa_gpio_init_raw(pinm);
r->phy_pin = pin;
return r;
}
maa_gpio_context
@@ -90,12 +98,13 @@ maa_gpio_init_raw(int pin)
dev->value_fp = -1;
dev->isr_value_fp = -1;
dev->pin = pin;
dev->phy_pin = -1;
char directory[MAX_SIZE];
snprintf(directory, MAX_SIZE, SYSFS_CLASS_GPIO "/gpio%d/", dev->pin);
struct stat dir;
if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
fprintf(stderr, "GPIO Pin already exporting, continuing.\n");
//fprintf(stderr, "GPIO Pin already exporting, continuing.\n");
dev->owner = 0; // Not Owner
} else {
int export = open(SYSFS_CLASS_GPIO "/export", O_WRONLY);
@@ -115,6 +124,17 @@ maa_gpio_init_raw(int pin)
return dev;
}
static maa_result_t
maa_gpio_write_register(maa_gpio_context dev,int value)
{
if (value == 1) {
*((unsigned *)dev->reg) |= (1<<dev->reg_bit_pos);
return MAA_SUCCESS;
}
*((unsigned *)dev->reg) &= ~(1<<dev->reg_bit_pos);
return MAA_SUCCESS;
}
static maa_result_t
maa_gpio_wait_interrupt(int fd)
{
@@ -395,6 +415,9 @@ maa_gpio_read(maa_gpio_context dev)
maa_result_t
maa_gpio_write(maa_gpio_context dev, int value)
{
if (dev->mmap == 1)
return maa_gpio_write_register(dev,value);
if (dev->value_fp == -1) {
maa_gpio_get_valfp(dev);
}
@@ -461,3 +484,45 @@ maa_gpio_owner(maa_gpio_context dev, maa_boolean_t own)
return MAA_SUCCESS;
}
maa_result_t
maa_gpio_use_mmaped(maa_gpio_context dev, maa_boolean_t mmap_en)
{
if (dev == NULL) {
return MAA_ERROR_INVALID_RESOURCE;
}
if (maa_pin_mode_test(dev->phy_pin, MAA_PIN_FAST_GPIO) == 0)
return MAA_ERROR_NO_RESOURCES;
maa_mmap_pin_t *mmp = maa_setup_mmap_gpio(dev->phy_pin);
if (mmp == NULL)
return MAA_ERROR_INVALID_RESOURCE;
if (mmap_en == 1) {
if (dev->mmap == 0) {
close(dev->value_fp);
int fd;
fd = open(mmp->mem_dev, O_RDWR);
if (fd < 1) {
fprintf(stderr, "Unable to open memory device\n");
return MAA_ERROR_INVALID_RESOURCE;
}
dev->reg_sz = mmp->mem_sz;
dev->reg = mmap(NULL, dev->reg_sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
dev->reg_bit_pos = mmp->bit_pos;
dev->mmap = 1;
return MAA_SUCCESS;
}
return MAA_ERROR_INVALID_PARAMETER;
}
if (mmap_en == 0) {
if (dev ->mmap == 1) {
munmap(dev->reg, dev->reg_sz);
dev->mmap = 0;
}
return MAA_ERROR_INVALID_PARAMETER;
}
return MAA_SUCCESS;
}