include/bsp/can.h

0001 /**
0002  * @file
0003  *
0004  * @ingroup RTEMSBSPsARMLPC176X
0005  *
0006  * @brief CAN controller for the mbed lpc1768 board.
0007  */
0008
0009 /*
0010  * Copyright (c) 2014 Taller Technologies.
0011  *
0012  * @author  Diaz Marcos (marcos.diaz@tallertechnologies.com)
0013  * @author  Daniel Chicco  (daniel.chicco@tallertechnologies.com)
0014  *
0015  * The license and distribution terms for this file may be
0016  * found in the file LICENSE in this distribution or at
0017  * http://www.rtems.org/license/LICENSE.
0018  */
0019
0020 #ifndef LPC176X_CAN_H
0021 #define LPC176X_CAN_H
0022
0023 #include <bsp.h>
0024 #include <bsp/io.h>
0025 #include <bsp/lpc176x.h>
0026
0027 #ifdef __cplusplus
0028 extern "C" {
0029 #endif /* __cplusplus */
0030
0031 /**
0032  * @brief The CAN devices of the board.
0033  */
0034 typedef enum {
0035   CAN_0,
0036   CAN_1,
0037   CAN_DEVICES_NUMBER
0038 } lpc176x_can_number;
0039
0040 /**
0041  * @brief  A CAN message represented for the registers of the device.
0042  */
0043 typedef struct {
0044   uint32_t info;
0045   uint32_t id;
0046   uint32_t data_a;
0047   uint32_t data_b;
0048 } registers_can_message;
0049
0050 /**
0051  * @brief A CAN message represented with each logical parts
0052  */
0053 typedef struct {
0054   unsigned int reserved1 : 16;
0055   unsigned int dlc       :  4;   /* Bits 16..19: DLC - Data Length Counter*/
0056   unsigned int reserved0 : 10;
0057   unsigned int rtr       :  1;   /* Bit 30: Set if this is a RTR message*/
0058   unsigned int type      :  1;   /* Bit 31: Set if this is a 29-bit ID message*/
0059   unsigned int id;               /* CAN Message ID (11-bit or 29-bit)*/
0060   unsigned char data[ 8 ];       /* CAN Message Data Bytes 0-7*/
0061 } low_level_can_message;
0062
0063 /**
0064  * @brief A CAN message represented of both forms.
0065  */
0066 typedef union {
0067   low_level_can_message low_level;
0068   registers_can_message registers;
0069 } can_message;
0070
0071 /**
0072  * @brief The possible interrupt sources for CAN.
0073  */
0074 typedef enum {
0075   IRQ_RX = 0,
0076   IRQ_TX,
0077   IRQ_ERROR,
0078   IRQ_OVERRUN,
0079   IRQ_WAKEUP,
0080   IRQ_PASSIVE,
0081   IRQ_ARB,
0082   IRQ_BUS,
0083   IRQ_READY,
0084   CAN_IRQ_NUMBER
0085 } can_irq_type;
0086
0087 /**
0088  * @brief An isr for a CAN interrupt
0089  *
0090  * @param number The CAN which rised the interrupt.
0091  */
0092 typedef void (*lpc176x_can_isr) ( lpc176x_can_number number );
0093
0094 /**
0095  * @brief A CAN frequency value
0096  */
0097 typedef unsigned int can_freq;
0098
0099 /**
0100  * @brief Opens CAN device.
0101  * @details It enables the module and gives it a clock, sets the pins,
0102  * disables the interrupts, sets the frequency and bypasses
0103  * the acceptance filter.
0104  *
0105  * @param  minor The device to open.
0106  * @param freq The desired frequency.
0107  * @return RTEMS_SUCCESFUL on success.
0108  */
0109 rtems_status_code can_open( lpc176x_can_number minor, can_freq freq );
0110
0111 /**
0112  * @brief Closes the passed CAN device and shut it down.
0113  *
0114  * @param minor The device to close.
0115  * @return RTEMS_SUCCESSFUL  if ok, RTEMS_INVALID_NUMBER for a bad parameter.
0116  */
0117 rtems_status_code can_close( lpc176x_can_number minor );
0118
0119 /**
0120  * @brief Reads the CAN device.
0121  *
0122  * @param minor The CAN device to read.
0123  * @param message The read message.
0124  * @return RTEMS_SUCCESSFUL if read ok, RTEMS_IO_ERROR otherwise.
0125  */
0126 rtems_status_code can_read(
0127   const lpc176x_can_number minor,
0128   can_message             *message
0129 );
0130
0131 /**
0132  * @brief Writes the passed CAN message into the selected CAN device.
0133  *
0134  * @param minor The device to write.
0135  * @param message The message to write.
0136  * @return RTEMS_SUCCESFUL if write ok. RTEMS_IO_ERROR otherwise.
0137  */
0138 rtems_status_code can_write(
0139   const lpc176x_can_number minor,
0140   const can_message *const message
0141 );
0142
0143 /**
0144  * @brief Registers an isr in the driver vector, and enables the interrupt
0145 *  in the device.
0146  *
0147  * @param number The CAN device to set
0148  * @param type The interrupt type.
0149  * @param isr The isr to register.
0150  * @return RTEMS_SUCCESSFUL if ok RTEMS_INVALID_NUMBER otherwise.
0151  */
0152 rtems_status_code can_register_isr(
0153   const lpc176x_can_number number,
0154   const can_irq_type       type,
0155   const lpc176x_can_isr    isr
0156 );
0157
0158 /**
0159  * @brief Creates a CAN message.
0160  * @details [long description]
0161  *
0162  * @param msg The created message.
0163  * @param _id The can id for the message.
0164  * @param _data The data of the message.
0165  * @param _len The length of the message.
0166  * @return RTEMS_SUCCESFUL if created, RTEMS_INVALID_NUMBER otherwise.
0167  */
0168 rtems_status_code create_can_message(
0169   can_message *const msg,
0170   const int          _id,
0171   const char *const  _data,
0172   const char         _len
0173 );
0174
0175 #ifdef __cplusplus
0176 }
0177 #endif /* __cplusplus */
0178
0179 #endif /* ifndef LPC176X_CAN_H */