incubator-nuttx/include/nuttx/serial.h

242 lines
9.0 KiB
C

/************************************************************************************
* serial.h
*
* Copyright (C) 2007 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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 Gregory Nutt 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 __SERIAL_H
#define __SERIAL_H
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <semaphore.h>
#include <nuttx/fs.h>
/************************************************************************************
* Definitions
************************************************************************************/
#define uart_setup(dev) dev->ops->setup(dev)
#define uart_shutdown(dev) dev->ops->shutdown(dev)
#define uart_enabletxint(dev) dev->ops->txint(dev, TRUE)
#define uart_disabletxint(dev) dev->ops->txint(dev, FALSE)
#define uart_enablerxint(dev) dev->ops->rxint(dev, TRUE)
#define uart_disablerxint(dev) dev->ops->rxint(dev, FALSE)
#define uart_rxfifonotempty(dev) dev->ops->rxfifonotempty(dev)
#define uart_txfifonotfull(dev) dev->ops->txfifonotfull(dev)
#define uart_txfifoempty(dev) dev->ops->txfifoempty(dev)
#define uart_send(dev,ch) dev->ops->send(dev,ch)
#define uart_receive(dev,s) dev->ops->receive(dev,s)
/************************************************************************************
* Private Types
************************************************************************************/
/* This structure defines one serial I/O buffer. The serial infrastructure will
* initialize the 'sem' field but all other fields must be initialized by the
* caller of uart_register().
*/
struct uart_buffer_s
{
sem_t sem; /* Used to control exclusive access to the buffer */
sint16 head; /* Index to the head [IN] index in the buffer */
sint16 tail; /* Index to the tail [OUT] index in the buffer */
sint16 size; /* The allocated size of the buffer */
FAR char *buffer; /* Pointer to the allocated buffer memory */
};
/* This structure defines all of the operations providd by the architecture specific
* logic. All fields must be provided with non-NULL function pointers by the
* caller of uart_register().
*/
struct uart_dev_s;
struct uart_ops_s
{
/* Configure the UART baud, bits, parity, fifos, etc. This method is called
* the first time that the serial port is opened.
*/
int (*setup)(struct uart_dev_s *dev);
/* Disable the UART. This method is called when the serial port is closed */
void (*shutdown)(struct uart_dev_s *dev);
/* This is the UART interrupt handler. It will be invoked when an interrupt
* received on the 'irq' It should call uart_transmitchars or uart_receivechar
* to perform the appropriate data transfers. The interrupt handling logic\
* must be able to map the 'irq' number into the approprite uart_dev_s
* structure in order to call these functions.
*/
int (*handler)(int irq, void *context);
/* All ioctl calls will be routed through this method */
int (*ioctl)(struct file *filep, int cmd, unsigned long arg);
/* Called (usually) from the interrupt level to receive one character from
* the UART. Error bits associated with the receipt are provided in the
* the return 'status'.
*/
int (*receive)(struct uart_dev_s *dev, unsigned int *status);
/* Call to enable or disable RX interrupts */
void (*rxint)(struct uart_dev_s *dev, boolean enable);
/* Return TRUE if the receive fifo is not empty */
boolean (*rxfifonotempty)(struct uart_dev_s *dev);
/* This method will send one byte on the UART */
void (*send)(struct uart_dev_s *dev, int ch);
/* Call to enable or disable TX interrupts */
void (*txint)(struct uart_dev_s *dev, boolean enable);
/* Return TRUE if the tranmsit fifo is not full. This is used to
* determine if *send can be called.
*/
boolean (*txfifonotfull)(struct uart_dev_s *dev);
/* Return TRUE if the transmit fifo is empty. This is used when the
* driver needs to make sure that all characters are "drained" from
* the TX fifo.
*/
boolean (*txfifoempty)(struct uart_dev_s *dev);
};
/* This is the device structure used by the driver. The caller of
* uart_register() must allocate and initialize this structure. The
* calling logic need only set all fields to zero except:
*
* 'irq', 'isconsole', 'xmit.buffer', 'rcv.buffer', the elements
* of 'ops', and 'private'
*
* The common logic will initialize all semaphores.
*/
struct uart_dev_s
{
int open_count; /* The number of times
* the device has been opened */
ubyte irq; /* IRQ associated with
* this UART */
boolean xmitwaiting; /* TRUE: User is waiting
* for space in xmit.buffer */
boolean recvwaiting; /* TRUE: User is waiting
* for space in recv.buffer */
boolean isconsole; /* TRUE: This is the serial console */
sem_t closesem; /* Locks out new opens while
* close is in progress */
sem_t xmitsem; /* Used to wakeup user waiting
* for space in xmit.buffer */
sem_t recvsem; /* Used to wakeup user waiting
* for sapce in recv.buffer */
struct uart_buffer_s xmit; /* Describes transmit buffer */
struct uart_buffer_s recv; /* Describes receive buffer */
const struct uart_ops_s *ops; /* Arch-specifics operations */
void *priv; /* Used by the arch-specific logic */
};
typedef struct uart_dev_s uart_dev_t;
/************************************************************************************
* Public Data
************************************************************************************/
/************************************************************************************
* Public Functions
************************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
/************************************************************************************
* Name: uart_register
*
* Description:
* Register serial console and serial ports.
*
************************************************************************************/
EXTERN int uart_register(const char *path, uart_dev_t *dev);
/************************************************************************************
* Name: uart_xmitchars
*
* Description:
* This function is called from the UART interrupt handler when an interrupt
* is received indicating that there is more space in the transmit FIFO. This
* function will send characters from the tail of the xmit buffer while the driver
* write() logic adds data to the head of the xmit buffer.
*
************************************************************************************/
EXTERN void uart_xmitchars(uart_dev_t *dev);
/************************************************************************************
* Name: uart_receivechars
*
* Description:
* This function is called from the UART interrupt handler when an interrupt
* is received indicating that are bytes available in the receive fifo. This
* function will add chars to head of receive buffer. Driver read() logic will take
* characters from the tail of the buffer.
*
************************************************************************************/
EXTERN void uart_recvchars(uart_dev_t *dev);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __SERIAL_H */