rt-thread/components/drivers/spi/spi_core.c

473 lines
12 KiB
C

/*
* File : spi_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
* 2012-01-08 bernard first version.
* 2012-02-03 bernard add const attribute to the ops.
* 2012-05-15 dzzxzz fixed the return value in attach_device.
* 2012-05-18 bernard Changed SPI message to message list.
* Added take/release SPI device/bus interface.
* 2012-09-28 aozima fixed rt_spi_release_bus assert error.
*/
#include <drivers/spi.h>
extern rt_err_t rt_spi_bus_device_init(struct rt_spi_bus *bus, const char *name);
extern rt_err_t rt_spidev_device_init(struct rt_spi_device *dev, const char *name);
rt_err_t rt_spi_bus_register(struct rt_spi_bus *bus,
const char *name,
const struct rt_spi_ops *ops)
{
rt_err_t result;
result = rt_spi_bus_device_init(bus, name);
if (result != RT_EOK)
return result;
/* initialize mutex lock */
rt_mutex_init(&(bus->lock), name, RT_IPC_FLAG_FIFO);
/* set ops */
bus->ops = ops;
/* initialize owner */
bus->owner = RT_NULL;
return RT_EOK;
}
rt_err_t rt_spi_bus_attach_device(struct rt_spi_device *device,
const char *name,
const char *bus_name,
void *user_data)
{
rt_err_t result;
rt_device_t bus;
/* get physical spi bus */
bus = rt_device_find(bus_name);
if (bus != RT_NULL && bus->type == RT_Device_Class_SPIBUS)
{
device->bus = (struct rt_spi_bus *)bus;
/* initialize spidev device */
result = rt_spidev_device_init(device, name);
if (result != RT_EOK)
return result;
rt_memset(&device->config, 0, sizeof(device->config));
device->parent.user_data = user_data;
return RT_EOK;
}
/* not found the host bus */
return -RT_ERROR;
}
rt_err_t rt_spi_configure(struct rt_spi_device *device,
struct rt_spi_configuration *cfg)
{
rt_err_t result;
RT_ASSERT(device != RT_NULL);
/* set configuration */
device->config.data_width = cfg->data_width;
device->config.mode = cfg->mode & RT_SPI_MODE_MASK ;
device->config.max_hz = cfg->max_hz ;
if (device->bus != RT_NULL)
{
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result == RT_EOK)
{
if (device->bus->owner == device)
{
device->bus->ops->configure(device, &device->config);
}
/* release lock */
rt_mutex_release(&(device->bus->lock));
}
}
return RT_EOK;
}
rt_err_t rt_spi_send_then_send(struct rt_spi_device *device,
const void *send_buf1,
rt_size_t send_length1,
const void *send_buf2,
rt_size_t send_length2)
{
rt_err_t result;
struct rt_spi_message message;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result == RT_EOK)
{
if (device->bus->owner != device)
{
/* not the same owner as current, re-configure SPI bus */
result = device->bus->ops->configure(device, &device->config);
if (result == RT_EOK)
{
/* set SPI bus owner */
device->bus->owner = device;
}
else
{
/* configure SPI bus failed */
result = -RT_EIO;
goto __exit;
}
}
/* send data1 */
message.send_buf = send_buf1;
message.recv_buf = RT_NULL;
message.length = send_length1;
message.cs_take = 1;
message.cs_release = 0;
message.next = RT_NULL;
result = device->bus->ops->xfer(device, &message);
if (result == 0)
{
result = -RT_EIO;
goto __exit;
}
/* send data2 */
message.send_buf = send_buf2;
message.recv_buf = RT_NULL;
message.length = send_length2;
message.cs_take = 0;
message.cs_release = 1;
message.next = RT_NULL;
result = device->bus->ops->xfer(device, &message);
if (result == 0)
{
result = -RT_EIO;
goto __exit;
}
result = RT_EOK;
}
else
{
return -RT_EIO;
}
__exit:
rt_mutex_release(&(device->bus->lock));
return result;
}
rt_err_t rt_spi_send_then_recv(struct rt_spi_device *device,
const void *send_buf,
rt_size_t send_length,
void *recv_buf,
rt_size_t recv_length)
{
rt_err_t result;
struct rt_spi_message message;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result == RT_EOK)
{
if (device->bus->owner != device)
{
/* not the same owner as current, re-configure SPI bus */
result = device->bus->ops->configure(device, &device->config);
if (result == RT_EOK)
{
/* set SPI bus owner */
device->bus->owner = device;
}
else
{
/* configure SPI bus failed */
result = -RT_EIO;
goto __exit;
}
}
/* send data */
message.send_buf = send_buf;
message.recv_buf = RT_NULL;
message.length = send_length;
message.cs_take = 1;
message.cs_release = 0;
message.next = RT_NULL;
result = device->bus->ops->xfer(device, &message);
if (result == 0)
{
result = -RT_EIO;
goto __exit;
}
/* recv data */
message.send_buf = RT_NULL;
message.recv_buf = recv_buf;
message.length = recv_length;
message.cs_take = 0;
message.cs_release = 1;
message.next = RT_NULL;
result = device->bus->ops->xfer(device, &message);
if (result == 0)
{
result = -RT_EIO;
goto __exit;
}
result = RT_EOK;
}
else
{
return -RT_EIO;
}
__exit:
rt_mutex_release(&(device->bus->lock));
return result;
}
rt_size_t rt_spi_transfer(struct rt_spi_device *device,
const void *send_buf,
void *recv_buf,
rt_size_t length)
{
rt_err_t result;
struct rt_spi_message message;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result == RT_EOK)
{
if (device->bus->owner != device)
{
/* not the same owner as current, re-configure SPI bus */
result = device->bus->ops->configure(device, &device->config);
if (result == RT_EOK)
{
/* set SPI bus owner */
device->bus->owner = device;
}
else
{
/* configure SPI bus failed */
rt_set_errno(-RT_EIO);
result = 0;
goto __exit;
}
}
/* initial message */
message.send_buf = send_buf;
message.recv_buf = recv_buf;
message.length = length;
message.cs_take = 1;
message.cs_release = 1;
message.next = RT_NULL;
/* transfer message */
result = device->bus->ops->xfer(device, &message);
if (result == 0)
{
rt_set_errno(-RT_EIO);
goto __exit;
}
}
else
{
rt_set_errno(-RT_EIO);
return 0;
}
__exit:
rt_mutex_release(&(device->bus->lock));
return result;
}
struct rt_spi_message *rt_spi_transfer_message(struct rt_spi_device *device,
struct rt_spi_message *message)
{
rt_err_t result;
struct rt_spi_message *index;
RT_ASSERT(device != RT_NULL);
/* get first message */
index = message;
if (index == RT_NULL)
return index;
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result != RT_EOK)
{
rt_set_errno(-RT_EBUSY);
return index;
}
/* reset errno */
rt_set_errno(RT_EOK);
/* configure SPI bus */
if (device->bus->owner != device)
{
/* not the same owner as current, re-configure SPI bus */
result = device->bus->ops->configure(device, &device->config);
if (result == RT_EOK)
{
/* set SPI bus owner */
device->bus->owner = device;
}
else
{
/* configure SPI bus failed */
rt_set_errno(-RT_EIO);
goto __exit;
}
}
/* transmit each SPI message */
while (index != RT_NULL)
{
/* transmit SPI message */
result = device->bus->ops->xfer(device, index);
if (result == 0)
{
rt_set_errno(-RT_EIO);
break;
}
index = index->next;
}
__exit:
/* release bus lock */
rt_mutex_release(&(device->bus->lock));
return index;
}
rt_err_t rt_spi_take_bus(struct rt_spi_device *device)
{
rt_err_t result = RT_EOK;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
result = rt_mutex_take(&(device->bus->lock), RT_WAITING_FOREVER);
if (result != RT_EOK)
{
rt_set_errno(-RT_EBUSY);
return -RT_EBUSY;
}
/* reset errno */
rt_set_errno(RT_EOK);
/* configure SPI bus */
if (device->bus->owner != device)
{
/* not the same owner as current, re-configure SPI bus */
result = device->bus->ops->configure(device, &device->config);
if (result == RT_EOK)
{
/* set SPI bus owner */
device->bus->owner = device;
}
else
{
/* configure SPI bus failed */
rt_set_errno(-RT_EIO);
/* release lock */
rt_mutex_release(&(device->bus->lock));
return -RT_EIO;
}
}
return result;
}
rt_err_t rt_spi_release_bus(struct rt_spi_device *device)
{
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
RT_ASSERT(device->bus->owner == device);
/* release lock */
rt_mutex_release(&(device->bus->lock));
return RT_EOK;
}
rt_err_t rt_spi_take(struct rt_spi_device *device)
{
rt_err_t result;
struct rt_spi_message message;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
rt_memset(&message, 0, sizeof(message));
message.cs_take = 1;
result = device->bus->ops->xfer(device, &message);
return result;
}
rt_err_t rt_spi_release(struct rt_spi_device *device)
{
rt_err_t result;
struct rt_spi_message message;
RT_ASSERT(device != RT_NULL);
RT_ASSERT(device->bus != RT_NULL);
rt_memset(&message, 0, sizeof(message));
message.cs_release = 1;
result = device->bus->ops->xfer(device, &message);
return result;
}