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/*
* File : at91_i2c_gpio.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006, RT-Thread Development Team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
* 2012-04-25 weety first version
*/
#include <rtdevice.h>
#include <rthw.h>
#include <at91sam926x.h>
static void at91_i2c_gpio_init()
{
at91_sys_write(AT91_PMC_PCER, 1 << AT91SAM9260_ID_PIOA); //enable PIOA clock
at91_sys_write(AT91_PIOA + PIO_PUER, (1 << 23));
at91_sys_write(AT91_PIOA + PIO_PER, (1 << 23));
at91_sys_write(AT91_PIOA + PIO_MDER, (1 << 23));
at91_sys_write(AT91_PIOA + PIO_PUER, (1 << 24));
at91_sys_write(AT91_PIOA + PIO_PER, (1 << 24));
at91_sys_write(AT91_PIOA + PIO_MDER, (1 << 24));
at91_sys_write(AT91_PIOA + PIO_OER, (1 << 23));
at91_sys_write(AT91_PIOA + PIO_OER, (1 << 24));
at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 23));
at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 24));
}
static void at91_set_sda(void *data, rt_int32_t state)
{
if (state)
{
at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 23));
}
else
{
at91_sys_write(AT91_PIOA + PIO_CODR, (1 << 23));
}
}
static void at91_set_scl(void *data, rt_int32_t state)
{
if (state)
{
at91_sys_write(AT91_PIOA + PIO_SODR, (1 << 24));
}
else
{
at91_sys_write(AT91_PIOA + PIO_CODR, (1 << 24));
}
}
static rt_int32_t at91_get_sda(void *data)
{
return at91_sys_read(AT91_PIOA + PIO_PDSR) & (1 << 23);
}
static rt_int32_t at91_get_scl(void *data)
{
return at91_sys_read(AT91_PIOA + PIO_PDSR) & (1 << 24);
}
static void at91_udelay (rt_uint32_t us)
{
rt_int32_t i;
for (; us > 0; us--)
{
i = 50000;
while(i > 0)
{
i--;
}
}
}
static const struct rt_i2c_bit_ops bit_ops = {
RT_NULL,
at91_set_sda,
at91_set_scl,
at91_get_sda,
at91_get_scl,
at91_udelay,
5,
100
};
rt_err_t at91_i2c_init(void)
{
struct rt_i2c_bus_device *bus;
bus = rt_malloc(sizeof(struct rt_i2c_bus_device));
if (bus == RT_NULL)
{
rt_kprintf("rt_malloc failed\n");
return -RT_ENOMEM;
}
rt_memset((void *)bus, 0, sizeof(struct rt_i2c_bus_device));
bus->priv = (void *)&bit_ops;
at91_i2c_gpio_init();
rt_i2c_bit_add_bus(bus, "i2c0");
return RT_EOK;
}
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