/* gpio.c
*
* GPIO driver for the Milkymist One board
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*
* COPYRIGHT (c) 2010, 2011 Sebastien Bourdeauducq
* COPYRIGHT (c) Yann Sionneau <yann.sionneau@telecom-sudparis.eu> (GSoC 2010)
* Telecom SudParis
*/
#define RTEMS_STATUS_CHECKS_USE_PRINTK
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <rtems.h>
#include <rtems/status-checks.h>
#include <bsp.h>
#include <rtems/libio.h>
#include "../include/system_conf.h"
#include "milkymist_gpio.h"
struct milkymist_gpio {
char *name;
unsigned int mask;
bool readonly;
};
static const struct milkymist_gpio gpio[] = {
{
.name = "/dev/led1",
.mask = GPIO_LED1,
.readonly = false
},
{
.name = "/dev/led2",
.mask = GPIO_LED2,
.readonly = false
},
};
rtems_device_driver gpio_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_status_code sc;
int i;
for (i=0;i<sizeof(gpio)/sizeof(struct milkymist_gpio);i++) {
sc = rtems_io_register_name(gpio[i].name, major, i);
RTEMS_CHECK_SC(sc, "create GPIO device");
}
return RTEMS_SUCCESSFUL;
}
rtems_device_driver gpio_read(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
unsigned int data;
rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *)arg;
if (rw_args->offset > 0) {
rw_args->bytes_moved = 0;
return RTEMS_SUCCESSFUL;
}
rw_args->bytes_moved = 1;
if (gpio[minor].readonly)
data = MM_READ(MM_GPIO_IN);
else
data = MM_READ(MM_GPIO_OUT);
if (data & gpio[minor].mask)
*(uint8_t *)rw_args->buffer = '1';
else
*(uint8_t *)rw_args->buffer = '0';
return RTEMS_SUCCESSFUL;
}
rtems_device_driver gpio_write(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *arg
)
{
rtems_libio_rw_args_t *rw_args = (rtems_libio_rw_args_t *)arg;
if (gpio[minor].readonly) {
rw_args->bytes_moved = 0;
return RTEMS_UNSATISFIED;
}
if (rw_args->offset > 0) {
rw_args->bytes_moved = 0;
return RTEMS_SUCCESSFUL;
}
rw_args->bytes_moved = 1;
if (*(uint8_t *)rw_args->buffer == '1')
MM_WRITE(MM_GPIO_OUT, MM_READ(MM_GPIO_OUT)|gpio[minor].mask);
else
MM_WRITE(MM_GPIO_OUT, MM_READ(MM_GPIO_OUT) & ~gpio[minor].mask);
return RTEMS_SUCCESSFUL;
}