incubator-nuttx/include/nuttx/i2c/i2c_slave.h

211 lines
7.5 KiB
C

/****************************************************************************
* include/nuttx/i2c/i2c_slave.h
*
* Copyright(C) 2016 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES(INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_I2C_I2C_SLAVE_H
#define __INCLUDE_NUTTX_I2C_I2C_SLAVE_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#ifdef CONFIG_I2C_SLAVE
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* I2C address calculation. Convert 7- and 10-bit address to 8-bit and
* 16-bit read/write address
*/
#define I2CS_READBIT 0x01
/* Convert 7- to 8-bit address */
#define I2CS_ADDR8(a) ((a) << 1)
#define I2CS_WRITEADDR8(a) I2CS_ADDR8(a)
#define I2CS_READADDR8(a) (I2CS_ADDR8(a) | I2CS_READBIT)
/* Convert 10- to 16-bit address */
#define I2CS_ADDR10H(a) (0xf0 | (((a) >> 7) & 0x06))
#define I2CS_ADDR10L(a) ((a) & 0xff)
#define I2CS_WRITEADDR10H(a) I2CS_ADDR10H(a)
#define I2CS_WRITEADDR10L(a) I2CS_ADDR10L(a)
#define I2CS_READADDR10H(a) (I2CS_ADDR10H(a) | I2CS_READBIT)
#define I2CS_READADDR10L(a) I2CS_ADDR10L(a)
/* Access macros ************************************************************/
/****************************************************************************
* Name: I2CS_SETOWNADDRESS
*
* Description:
* Set our own I2C address. Calling this function enables Slave mode and
* disables Master mode on the I2C bus (note that I2C is a bus, where
* multiple masters and slave may be handled by one device driver).
*
* One may register a callback to be notified about reception. During the
* slave mode reception, the methods READ and WRITE must be used to
* to handle reads and writes from a master.
*
* Input Parameters:
* dev - Device-specific state data
* address - Our own slave address; If it is 0x00, then the device driver
* listens to general call
* nbits - The number of address bits provided (7 or 10)
*
* Returned Value:
* OK on valid address and if the same address has not been assigned
* to another instance sharing the same port. Otherwise ERROR is returned.
*
****************************************************************************/
#define I2CS_SETOWNADDRESS(d,a,n) ((d)->ops->setownaddress(d,a,n))
/****************************************************************************
* Name: I2CS_WRITE
*
* Description:
* Send a block of data on I2C using the previously selected I2C
* frequency and slave address. Each write operational will be an 'atomic'
* operation in the sense that any other I2C actions will be serialized
* and pend until this write completes. Required.
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to the read-only buffer of data to be written to device
* buflen - The number of bytes to send from the buffer
*
* Returned Value:
* 0: success, <0: A negated errno
*
****************************************************************************/
#define I2CS_WRITE(d,b,l) ((d)->ops->write(d,b,l))
/****************************************************************************
* Name: I2CS_READ
*
* Description:
* Receive a block of data from I2C using the previously selected I2C
* frequency and slave address. Each read operational will be an 'atomic'
* operation in the sense that any other I2C actions will be serialized
* and pend until this read completes. Required.
*
* Input Parameters:
* dev - Device-specific state data
* buffer - A pointer to a buffer of data to receive the data from the device
* buflen - The requested number of bytes to be read
*
* Returned Value:
* 0: success, <0: A negated errno
*
****************************************************************************/
#define I2CS_READ(d,b,l) ((d)->ops->read(d,b,l))
/****************************************************************************
* Name: I2CS_REGISTERCALLBACK
*
* Description:
* Register to receive a callback when something is received on I2C.
*
* Input Parameters:
* dev - Device-specific state data
* callback - The function to be called when something has been received.
* arg - User provided argument to be used with the callback
*
* Returned Value:
* 0: success, <0: A negated errno
*
****************************************************************************/
#define I2CS_REGISTERCALLBACK(d,c,a) ((d)->ops->registercallback(d,c,a))
/****************************************************************************
* Public Types
****************************************************************************/
/* The I2C vtable */
struct i2c_slave_s;
struct i2c_slaveops_s
{
int (*setownaddress)(FAR struct i2c_slave_s *dev, int addr, int nbits);
int (*write)(FAR struct i2c_slave_s *dev, FAR const uint8_t *buffer,
int buflen);
int (*read)(FAR struct i2c_slave_s *dev, FAR uint8_t *buffer,
int buflen);
int (*registercallback)(FAR struct i2c_slave_s *dev,
int (*callback)(FAR void *arg), FAR void *arg);
};
/* I2C private data. This structure only defines the initial fields of the
* structure visible to the I2C client. The specific implementation may
* add additional, device specific fields after the vtable.
*/
struct i2c_slave_s
{
const struct i2c_slaveops_s *ops; /* I2C vtable */
};
/****************************************************************************
* Public Functions
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* CONFIG_I2C_SLAVE */
#endif /* __INCLUDE_NUTTX_I2C_I2C_SLAVE_H */