incubator-nuttx/include/nuttx/can.h

305 lines
11 KiB
C

/************************************************************************************
* include/nuttx/can.h
*
* Copyright (C) 2008 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 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 __NUTTX_CAN_H
#define __NUTTX_CAN_H
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <semaphore.h>
#include <nuttx/fs.h>
/************************************************************************************
* Definitions
************************************************************************************/
/* Default configuration settings that may be overridden in the board configuration.
* file. The configured size is limited to 255 to fit into a ubyte.
*/
#if !defined(CONFIG_CAN_FIFOSIZE)
# define CONFIG_CAN_FIFOSIZE 8
#elif CONFIG_CAN_FIFOSIZE > 255
# undef CONFIG_CAN_FIFOSIZE
# define CONFIG_CAN_FIFOSIZE 255
#endif
#if !defined(CONFIG_CAN_NPENDINGRTR)
# define CONFIG_CAN_NPENDINGRTR 4
#elif CONFIG_CAN_NPENDINGRTR > 255
# undef CONFIG_CAN_NPENDINGRTR
# define CONFIG_CAN_NPENDINGRTR 255
#endif
/* Convenience macros */
#define dev_reset(dev) dev->cd_ops->co_reset(dev)
#define dev_setup(dev) dev->cd_ops->co_setup(dev)
#define dev_shutdown(dev) dev->cd_ops->co_shutdown(dev)
#define dev_txint(dev,enable) dev->cd_ops->co_txint(dev,enable)
#define dev_rxint(dev,enable) dev->cd_ops->co_rxint(dev,enable)
#define dev_ioctl(dev,cmd,arg) dev->cd_ops->co_ioctl(dev,cmd,arg)
#define dev_remoterequest(dev,id) dev->cd_ops->co_remoterequest(dev,id)
#define dev_send(dev,m) dev->cd_ops->co_send(dev,m)
#define dev_txempty(dev) dev->cd_ops->co_txempty(dev)
/* CAN message support */
#define CAN_MAXDATALEN 8
#define CAN_ID(hdr) ((uint16)(hdr) >> 5)
#define CAN_RTR(hdr) (((hdr) & 0x0010) != 0)
#define CAN_DLC(hdr) ((hdr) & 0x0f)
#define CAN_MSGLEN(hdr) (sizeof(struct can_msg_s) - (CAN_MAXDATALEN - CAN_DLC(hdr)))
/* Built-in ioctl commands
*
* CANIOCTL_RTR: Send the remote transmission request and wait for the response.
*/
#define CANIOCTL_RTR 1 /* Argument is a reference to struct canioctl_rtr_s */
/* CANIOCTL_USER: Device specific ioctl calls can be supported with cmds greater
* than this value
*/
#define CANIOCTL_USER 2
/************************************************************************************
* Private Types
************************************************************************************/
/* CAN-message Format
*
* One CAN-message consists of a maximum of 10 bytes. A message is composed of at
* least the first 2 bytes (when there are no data bytes).
*
* Byte 0: Bits 0-7: Bits 3-10 of the 11-bit CAN identifier
* Byte 1: Bits 5-7: Bits 0-2 of the 11-bit CAN identifier
* Bit 4: Remote Tranmission Request (RTR)
* Bits 0-3: Data Length Code (DLC)
* Bytes 2-10: CAN data
*
* The struct can_msg_s holds this information in a user-friendly, unpacked form.
* This is the form that is used at the read() and write() driver interfaces. The
* message structure is actually variable length -- the true length is given by
* the CAN_MSGLEN macro.
*/
struct can_msg_s
{
uint16 cm_hdr; /* The 16-bit CAN header */
ubyte cm_data[CAN_MAXDATALEN]; /* CAN message data (0-8 byte) */
};
/* This structure defines a CAN message FIFO. */
struct can_fifo_s
{
sem_t cf_sem; /* Counting semaphore */
ubyte cf_head; /* Index to the head [IN] index in the circular buffer */
ubyte cf_tail; /* Index to the tail [OUT] index in the circular buffer */
/* Circular buffer of CAN messages */
struct can_msg_s cf_buffer[CONFIG_CAN_FIFOSIZE];
};
/* The following structure define the logic to handle one RTR message transaction */
struct can_rtrwait_s
{
sem_t cr_sem; /* Wait for RTR response */
uint16 cr_id; /* The ID that is waited for */
FAR struct can_msg_s *cr_msg; /* This is where the RTR reponse goes */
};
/* 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 can_register().
*/
struct can_dev_s;
struct can_ops_s
{
/* Reset the CAN device. Called early to initialize the hardware. This
* is called, before co_setup() and on error conditions.
*/
CODE void (*co_reset)(FAR struct can_dev_s *dev);
/* Configure the CAN. This method is called the first time that the CAN
* device is opened. This will occur when the port is first opened.
* This setup includes configuring and attaching CAN interrupts. Interrupts
* are all disabled upon return.
*/
CODE int (*co_setup)(FAR struct can_dev_s *dev);
/* Disable the CAN. This method is called when the CAN device is closed.
* This method reverses the operation the setup method.
*/
CODE void (*co_shutdown)(FAR struct can_dev_s *dev);
/* Call to enable or disable RX interrupts */
CODE void (*co_rxint)(FAR struct can_dev_s *dev, boolean enable);
/* Call to enable or disable TX interrupts */
CODE void (*co_txint)(FAR struct can_dev_s *dev, boolean enable);
/* All ioctl calls will be routed through this method */
CODE int (*co_ioctl)(FAR struct can_dev_s *dev, int cmd, unsigned long arg);
/* Send a remote request */
CODE int (*co_remoterequest)(FAR struct can_dev_s *dev, uint16 id);
/* This method will send one message on the CAN */
CODE int (*co_send)(FAR struct can_dev_s *dev, FAR struct can_msg_s *msg);
/* Return TRUE if all message have been sent. If for example, the CAN
* hardware implements FIFOs, then this would mean the the transmit FIFO is
* empty. This method is called when the driver needs to make sure that
* all characters are "drained" from the TX hardware before calling co_shutdown().
*/
CODE boolean (*co_txempty)(FAR struct can_dev_s *dev);
};
/* This is the device structure used by the driver. The caller of
* can_register() must allocate and initialize this structure. The
* calling logic need only set all fields to zero except:
*
* The elements of 'cd_ops', and 'cd_priv'
*
* The common logic will initialize all semaphores.
*/
struct can_dev_s
{
ubyte cd_ocount; /* The number of times the device has been opened */
ubyte cd_npendrtr; /* Number of pending RTR messages */
sem_t cd_closesem; /* Locks out new opens while close is in progress */
sem_t cd_recvsem; /* Used to wakeup user waiting for space in cd_recv.buffer */
struct can_fifo_s cd_xmit; /* Describes transmit FIFO */
struct can_fifo_s cd_recv; /* Describes receive FIFO */
/* List of pending RTR requests */
struct can_rtrwait_s cd_rtr[CONFIG_CAN_NPENDINGRTR];
FAR const struct can_ops_s *cd_ops; /* Arch-specific operations */
FAR void *cd_priv; /* Used by the arch-specific logic */
};
/* Structures used with ioctl calls */
struct canioctl_rtr_s
{
uint16 ci_id; /* The 11-bit ID to use in the RTR message */
FAR struct can_msg_s *ci_msg; /* The location to return the RTR response */
};
/************************************************************************************
* Public Data
************************************************************************************/
/************************************************************************************
* Public Functions
************************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C" {
#else
#define EXTERN extern
#endif
/************************************************************************************
* Name: can_register
*
* Description:
* Register a CAN driver.
*
************************************************************************************/
EXTERN int can_register(FAR const char *path, FAR struct can_dev_s *dev);
/************************************************************************************
* Name: can_receive
*
* Description:
* Called from the CAN interrupt handler when new read data is available
*
* Parameters:
* dev - The specifi CAN device
* hdr - The 16-bit CAN header
* data - An array contain the CAN data.
*
* Return:
* OK on success; a negated errno on failure.
*
************************************************************************************/
EXTERN int can_receive(FAR struct can_dev_s *dev, uint16 hdr, FAR ubyte *data);
/************************************************************************************
* Name: can_txdone
*
* Description:
* Called from the CAN interrupt handler at the completion of a send operation.
*
* Parameters:
* dev - The specifi CAN device
* hdr - The 16-bit CAN header
* data - An array contain the CAN data.
*
* Return:
* OK on success; a negated errno on failure.
*
************************************************************************************/
EXTERN int can_txdone(FAR struct can_dev_s *dev);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __NUTTX_CAN_H */