rt-thread-official/components/drivers/i2c/i2c_core.c

142 lines
3.9 KiB
C

/*
* File : i2c_core.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006 - 2012, 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>
static struct rt_mutex i2c_core_lock;
rt_err_t rt_i2c_bus_device_register(struct rt_i2c_bus_device *bus,
const char *bus_name)
{
rt_err_t res = RT_EOK;
rt_mutex_init(&bus->lock, "i2c_bus_lock", RT_IPC_FLAG_FIFO);
rt_mutex_take(&i2c_core_lock, RT_WAITING_FOREVER);
if (bus->timeout == 0)
bus->timeout = RT_TICK_PER_SECOND;
res = rt_i2c_bus_device_device_init(bus, bus_name);
i2c_dbg("I2C bus [%s] registered\n", bus_name);
rt_mutex_release(&i2c_core_lock);
return res;
}
struct rt_i2c_bus_device *rt_i2c_bus_device_find(const char *bus_name)
{
struct rt_i2c_bus_device *bus;
rt_device_t dev = rt_device_find(bus_name);
if (dev == RT_NULL || dev->type != RT_Device_Class_I2CBUS)
{
i2c_dbg("I2C bus %s not exist\n", bus_name);
return RT_NULL;
}
bus = (struct rt_i2c_bus_device *)dev->user_data;
return bus;
}
rt_size_t rt_i2c_transfer(struct rt_i2c_bus_device *bus,
struct rt_i2c_msg msgs[],
rt_uint32_t num)
{
rt_size_t ret;
if (bus->ops->master_xfer)
{
#ifdef RT_I2C_DEBUG
for (ret = 0; ret < num; ret++)
{
i2c_dbg("msgs[%d] %c, addr=0x%02x, len=%d%s\n", ret,
(msgs[ret].flags & RT_I2C_RD) ? 'R' : 'W',
msgs[ret].addr, msgs[ret].len);
}
#endif
rt_mutex_take(&bus->lock, RT_WAITING_FOREVER);
ret = bus->ops->master_xfer(bus, msgs, num);
rt_mutex_release(&bus->lock);
return ret;
}
else
{
i2c_dbg("I2C bus operation not supported\n");
return 0;
}
}
rt_size_t rt_i2c_master_send(struct rt_i2c_bus_device *bus,
rt_uint16_t addr,
rt_uint16_t flags,
const rt_uint8_t *buf,
rt_uint32_t count)
{
rt_size_t ret;
struct rt_i2c_msg msg;
msg.addr = addr;
msg.flags = flags & RT_I2C_ADDR_10BIT;
msg.len = count;
msg.buf = (rt_uint8_t *)buf;
ret = rt_i2c_transfer(bus, &msg, 1);
return (ret > 0) ? count : ret;
}
rt_size_t rt_i2c_master_recv(struct rt_i2c_bus_device *bus,
rt_uint16_t addr,
rt_uint16_t flags,
rt_uint8_t *buf,
rt_uint32_t count)
{
rt_size_t ret;
struct rt_i2c_msg msg;
RT_ASSERT(bus != RT_NULL);
msg.addr = addr;
msg.flags = flags & RT_I2C_ADDR_10BIT;
msg.flags |= RT_I2C_RD;
msg.len = count;
msg.buf = buf;
ret = rt_i2c_transfer(bus, &msg, 1);
return (ret > 0) ? count : ret;
}
rt_err_t rt_i2c_core_init(void)
{
return rt_mutex_init(&i2c_core_lock, "i2c_core_lock", RT_IPC_FLAG_FIFO);
}