[7b35a36] | 1 | /** |
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| 2 | * @file can.c |
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| 3 | * |
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| 4 | * @ingroup lpc176x |
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| 5 | * |
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| 6 | * @brief CAN controller for the mbed lpc1768 board. |
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| 7 | */ |
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| 8 | |
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| 9 | /* |
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| 10 | * Copyright (c) 2014 Taller Technologies. |
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| 11 | * |
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| 12 | * @author Diaz Marcos (marcos.diaz@tallertechnologies.com) |
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| 13 | * @author Daniel Chicco (daniel.chicco@tallertechnologies.com) |
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| 14 | * |
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| 15 | * The license and distribution terms for this file may be |
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| 16 | * found in the file LICENSE in this distribution or at |
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[d4edbdbc] | 17 | * http://www.rtems.org/license/LICENSE. |
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[7b35a36] | 18 | */ |
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| 19 | |
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| 20 | #include <rtems/status-checks.h> |
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| 21 | #include <bsp/irq.h> |
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| 22 | #include <bsp/can.h> |
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| 23 | #include <bsp/can-defs.h> |
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| 24 | #include <bsp/mbed-pinmap.h> |
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[b2ed712] | 25 | #include <string.h> |
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[7b35a36] | 26 | |
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| 27 | /** |
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| 28 | * @brief The standard isr to be installed for all the can devices. |
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| 29 | * |
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| 30 | * @param arg unused. |
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| 31 | */ |
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| 32 | static void can_isr( void *arg ); |
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| 33 | |
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| 34 | /** |
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| 35 | * @brief Vector of isr for the can_driver . |
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| 36 | */ |
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| 37 | lpc176x_can_isr_vector isr_vector; |
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| 38 | |
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| 39 | /** |
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| 40 | * @brief Represents all the can devices, and useful things for initialization. |
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| 41 | */ |
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| 42 | static const can_driver_entry can_driver_table[ CAN_DEVICES_NUMBER ] = |
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| 43 | { |
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| 44 | { |
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| 45 | .device = (can_device *) CAN1_BASE_ADDR, |
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| 46 | .module = LPC176X_MODULE_CAN_0, |
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| 47 | .pconp_pin = LPC176X_SCB_PCONP_CAN_1, |
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| 48 | .pins = { DIP9, DIP10 }, |
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| 49 | .pinfunction = LPC176X_PIN_FUNCTION_01 |
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| 50 | }, |
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| 51 | { |
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| 52 | .device = (can_device *) CAN2_BASE_ADDR, |
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| 53 | .module = LPC176X_MODULE_CAN_1, |
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| 54 | .pconp_pin = LPC176X_SCB_PCONP_CAN_2, |
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| 55 | .pins = { DIP30, DIP29 }, |
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| 56 | .pinfunction = LPC176X_PIN_FUNCTION_10 |
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| 57 | } |
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| 58 | }; |
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| 59 | |
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| 60 | /** |
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| 61 | * @brief The CAN acceptance filter. |
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| 62 | */ |
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| 63 | can_acceptance_filter *const acceptance_filter_device = |
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| 64 | (can_acceptance_filter *) CAN_ACCEPT_BASE_ADDR; |
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| 65 | |
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| 66 | /** |
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| 67 | * @brief Sets RX and TX pins for the passed can device number. |
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| 68 | * |
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| 69 | * @param cannumber CAN controller to be used. |
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| 70 | */ |
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| 71 | static inline void setpins( const lpc176x_can_number cannumber ) |
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| 72 | { |
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| 73 | const can_driver_entry *const can_driver = &can_driver_table[ cannumber ]; |
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| 74 | |
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| 75 | lpc176x_pin_select( can_driver->pins[ CAN_TX_PIN ], |
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| 76 | can_driver->pinfunction ); |
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| 77 | lpc176x_pin_select( can_driver->pins[ CAN_RX_PIN ], |
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| 78 | can_driver->pinfunction ); |
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| 79 | } |
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| 80 | |
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| 81 | rtems_status_code can_close( const lpc176x_can_number minor ) |
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| 82 | { |
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| 83 | rtems_status_code sc = RTEMS_INVALID_NUMBER; |
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| 84 | |
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| 85 | if ( CAN_DRIVER_IS_MINOR_VALID( minor ) ) { |
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| 86 | sc = RTEMS_SUCCESSFUL; |
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| 87 | const can_driver_entry *const can_driver = &can_driver_table[ minor ]; |
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| 88 | lpc176x_module_disable( can_driver->module ); |
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| 89 | } |
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| 90 | |
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| 91 | /*else wrong parameters. return RTEMS_INVALID_NUMBER*/ |
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| 92 | |
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| 93 | return sc; |
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| 94 | } |
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| 95 | |
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| 96 | /** |
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| 97 | * @brief Enables CAN device. |
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| 98 | * |
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| 99 | * @param obj The device to be enabled. |
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| 100 | */ |
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| 101 | static inline void can_enable( const can_driver_entry *const obj ) |
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| 102 | { |
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| 103 | if ( obj->device->MOD & CAN_MOD_RM ) { |
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| 104 | obj->device->MOD &= ~( CAN_MOD_RM ); |
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| 105 | } |
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| 106 | } |
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| 107 | |
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| 108 | /** |
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| 109 | * @brief Disables CAN device to set parameters, and returns the previous value |
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| 110 | * of the MOD register. |
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| 111 | * |
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| 112 | * @param obj The device to disable. |
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| 113 | * @return The previous status of MOD register. |
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| 114 | */ |
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| 115 | static inline uint32_t can_disable( const can_driver_entry *const obj ) |
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| 116 | { |
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| 117 | const uint32_t sm = obj->device->MOD; |
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| 118 | |
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| 119 | obj->device->MOD |= CAN_MOD_RM; |
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| 120 | |
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| 121 | return sm; |
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| 122 | } |
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| 123 | |
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| 124 | /** |
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| 125 | * @brief Resets the error count. |
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| 126 | * |
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| 127 | * @param obj which device reset. |
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| 128 | */ |
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| 129 | static inline void can_reset( const can_driver_entry *const obj ) |
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| 130 | { |
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| 131 | can_disable( obj ); |
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| 132 | obj->device->GSR = 0; /* Reset error counter when CANxMOD is in reset*/ |
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| 133 | } |
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| 134 | |
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| 135 | /** |
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| 136 | * @brief This table has the sampling points as close to 75% as possible. |
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| 137 | * The first value is TSEG1, the second is TSEG2. |
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| 138 | */ |
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| 139 | static const unsigned int timing_pts[ MAX_TSEG1_TSEG2_BITS + |
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| 140 | 1 ][ CAN_NUMBER_OF_TSEG ] = { |
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| 141 | { 0x0, 0x0 }, /* 2, 50%*/ |
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| 142 | { 0x1, 0x0 }, /* 3, 67%*/ |
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| 143 | { 0x2, 0x0 }, /* 4, 75%*/ |
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| 144 | { 0x3, 0x0 }, /* 5, 80%*/ |
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| 145 | { 0x3, 0x1 }, /* 6, 67%*/ |
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| 146 | { 0x4, 0x1 }, /* 7, 71%*/ |
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| 147 | { 0x5, 0x1 }, /* 8, 75%*/ |
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| 148 | { 0x6, 0x1 }, /* 9, 78%*/ |
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| 149 | { 0x6, 0x2 }, /* 10, 70%*/ |
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| 150 | { 0x7, 0x2 }, /* 11, 73%*/ |
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| 151 | { 0x8, 0x2 }, /* 12, 75%*/ |
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| 152 | { 0x9, 0x2 }, /* 13, 77%*/ |
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| 153 | { 0x9, 0x3 }, /* 14, 71%*/ |
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| 154 | { 0xA, 0x3 }, /* 15, 73%*/ |
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| 155 | { 0xB, 0x3 }, /* 16, 75%*/ |
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| 156 | { 0xC, 0x3 }, /* 17, 76%*/ |
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| 157 | { 0xD, 0x3 }, /* 18, 78%*/ |
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| 158 | { 0xD, 0x4 }, /* 19, 74%*/ |
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| 159 | { 0xE, 0x4 }, /* 20, 75%*/ |
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| 160 | { 0xF, 0x4 }, /* 21, 76%*/ |
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| 161 | { 0xF, 0x5 }, /* 22, 73%*/ |
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| 162 | { 0xF, 0x6 }, /* 23, 70%*/ |
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| 163 | { 0xF, 0x7 }, /* 24, 67%*/ |
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| 164 | }; |
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| 165 | |
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| 166 | /** |
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| 167 | * @brief Checks if divisor is a divisor of value. |
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| 168 | * |
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| 169 | * @param value The number to be divided. |
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| 170 | * @param divisor The divisor to check. |
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| 171 | * |
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| 172 | * @return true if "number" is divided by "divisor"; false otherwise. |
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| 173 | */ |
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| 174 | static inline bool is_divisor( |
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| 175 | const uint32_t value, |
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| 176 | const uint16_t divisor |
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| 177 | ) |
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| 178 | { |
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| 179 | return ( ( value % divisor ) == 0 ); |
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| 180 | } |
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| 181 | |
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| 182 | /** |
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| 183 | * @brief Gets the size of the two tseg values added according to the given |
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| 184 | * bitwidth and brp (The CAN prescaler). |
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| 185 | * |
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| 186 | * @param bitwidth The total bitwidth of a CAN bit (in pclk clocks). |
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| 187 | * @param brp The CAN clock prescaler. |
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| 188 | * |
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| 189 | * @return The value of tseg1 + tseg2 of the CAN bit. It is useful |
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| 190 | * to serve for index for timing_pts array). |
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| 191 | */ |
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| 192 | static inline uint32_t get_tseg_bit_size( |
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| 193 | const uint32_t bitwidth, |
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| 194 | const uint16_t brp |
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| 195 | ) |
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| 196 | { |
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| 197 | return ( ( bitwidth / ( brp + CAN_BRP_EXTRA_BIT ) ) - CAN_TSEG_EXTRA_BITS ); |
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| 198 | } |
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| 199 | |
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| 200 | /** |
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| 201 | * @brief Gets the brp and tsegbitsize in order to achieve the desired bitwidth. |
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| 202 | * @details The following must be fullfilled: |
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| 203 | *(brp + CAN_BRP_EXTRA_BIT) * (tsegbitsize + CAN_TSEG_EXTRA_BITS) == bitwidth |
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| 204 | * |
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| 205 | * @param bitwidth The bitwidth that we need to achieve. |
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| 206 | * @param brp Here it returns the calculated brp value. |
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| 207 | * @param tsegbitsize Here it returns the calculated tseg bit size value. |
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| 208 | * @return true if brp and tsegbitsize have been calculated. |
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| 209 | */ |
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| 210 | static inline bool get_brp_and_bitsize( |
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| 211 | const uint32_t bitwidth, |
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| 212 | uint16_t *const brp, |
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| 213 | uint32_t *const tsegbitsize |
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| 214 | ) |
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| 215 | { |
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| 216 | bool hit = false; |
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| 217 | |
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| 218 | while ( ( !hit ) && ( *brp < bitwidth / MIN_NUMBER_OF_CAN_BITS ) ) { |
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| 219 | if ( ( is_divisor( bitwidth, *brp + CAN_BRP_EXTRA_BIT ) ) |
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| 220 | && ( get_tseg_bit_size( bitwidth, *brp ) < MAX_TSEG1_TSEG2_BITS ) ) { |
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| 221 | hit = true; |
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| 222 | *tsegbitsize = get_tseg_bit_size( bitwidth, *brp ); |
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| 223 | } else { /*Correct values not found, keep looking*/ |
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| 224 | ( *brp )++; |
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| 225 | } |
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| 226 | } |
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| 227 | |
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| 228 | return hit; |
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| 229 | } |
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| 230 | |
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| 231 | /** |
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| 232 | * @brief Constructs the btr register with the passed arguments. |
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| 233 | * |
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| 234 | * @param tsegbitsize The size tseg bits to set. |
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| 235 | * @param psjw The sjw to set. |
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| 236 | * @param brp The prescaler value to set. |
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| 237 | * @return The constructed btr register. |
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| 238 | */ |
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| 239 | static inline uint32_t get_btr( |
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| 240 | const uint32_t tsegbitsize, |
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| 241 | const unsigned char psjw, |
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| 242 | const uint32_t brp |
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| 243 | ) |
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| 244 | { |
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| 245 | const uint32_t tseg2_value_masked = |
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| 246 | ( ( timing_pts[ tsegbitsize ][ CAN_TSEG2 ] << CAN_BTR_TSEG2_SHIFT ) & |
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| 247 | CAN_BTR_TSEG2_MASK ); |
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| 248 | const uint32_t tseg1_value_masked = |
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| 249 | ( ( timing_pts[ tsegbitsize ][ CAN_TSEG1 ] << |
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| 250 | CAN_BTR_TSEG1_SHIFT ) & CAN_BTR_TSEG1_MASK ); |
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| 251 | const uint32_t psjw_value_masked = |
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| 252 | ( ( psjw << CAN_BTR_SJW_SHIFT ) & CAN_BTR_SJW_MASK ); |
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| 253 | const uint32_t brp_value_masked = |
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| 254 | ( ( brp << CAN_BTR_BRP_SHIFT ) & CAN_BTR_BRP_MASK ); |
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| 255 | |
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| 256 | return tseg1_value_masked | tseg2_value_masked | |
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| 257 | psjw_value_masked | brp_value_masked; |
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| 258 | } |
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| 259 | |
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| 260 | /** |
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| 261 | * @brief Calculates and returns a bit timing register (btr) for the desired |
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| 262 | * canclk frequency using the passed psjw, system clock and peripheral clock. |
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| 263 | * |
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| 264 | * @param systemclk The clock of the system (in Hz). |
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| 265 | * @param pclkdiv The peripheral clock divisor for the can device. |
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| 266 | * @param canclk The desired frequency for CAN (in Hz). |
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| 267 | * @param psjw The desired psjw. |
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| 268 | * @return The btr register value if found, WRONG_BTR_VALUE otherwise. |
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| 269 | */ |
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| 270 | static inline unsigned int can_speed( |
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| 271 | const unsigned int systemclk, |
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| 272 | const unsigned int pclkdiv, |
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| 273 | const unsigned int canclk, |
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| 274 | const unsigned char psjw |
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| 275 | ) |
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| 276 | { |
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| 277 | uint32_t btr = WRONG_BTR_VALUE; |
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| 278 | const uint32_t bitwidth = systemclk / ( pclkdiv * canclk ); |
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| 279 | |
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| 280 | /* This is for the brp (prescaler) to start searching a reachable multiple.*/ |
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| 281 | uint16_t brp = bitwidth / MAX_NUMBER_OF_CAN_BITS; |
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| 282 | uint32_t tsegbitsize; |
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| 283 | |
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| 284 | if ( get_brp_and_bitsize( bitwidth, &brp, &tsegbitsize ) ) { |
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| 285 | btr = get_btr( tsegbitsize, psjw, brp ); |
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| 286 | } |
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| 287 | |
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| 288 | return btr; |
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| 289 | } |
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| 290 | |
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| 291 | /** |
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| 292 | * @brief Configures the desired CAN device with the desired frequency. |
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| 293 | * |
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| 294 | * @param obj The can device to configure. |
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| 295 | * @param f The desired frequency. |
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| 296 | * |
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| 297 | * @return RTEMS_SUCCESSFUL if could be set, RTEMS_INVALID_NUMBER otherwise. |
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| 298 | */ |
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| 299 | static rtems_status_code can_frequency( |
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| 300 | const can_driver_entry *const obj, |
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| 301 | const can_freq freq |
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| 302 | ) |
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| 303 | { |
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| 304 | rtems_status_code sc = RTEMS_INVALID_NUMBER; |
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| 305 | const uint32_t btr = can_speed( LPC176X_CCLK, LPC176X_PCLKDIV, freq, 1 ); |
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| 306 | |
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| 307 | if ( btr != WRONG_BTR_VALUE ) { |
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| 308 | sc = RTEMS_SUCCESSFUL; |
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| 309 | uint32_t modmask = can_disable( obj ); |
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| 310 | obj->device->BTR = btr; |
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| 311 | obj->device->MOD = modmask; |
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| 312 | } /*else couldnt found a good timing for the desired frequency, |
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| 313 | return RTEMS_INVALID_NUMBER.*/ |
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| 314 | |
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| 315 | return sc; |
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| 316 | } |
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| 317 | |
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| 318 | /** |
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| 319 | * @brief Installs the interrupt handler in rtems. |
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| 320 | */ |
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| 321 | static inline rtems_status_code can_initialize( void ) |
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| 322 | { |
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| 323 | return rtems_interrupt_handler_install( |
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| 324 | LPC176X_IRQ_CAN, |
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| 325 | "can_interrupt", |
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| 326 | RTEMS_INTERRUPT_UNIQUE, |
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| 327 | can_isr, |
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| 328 | NULL |
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| 329 | ); |
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| 330 | } |
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| 331 | |
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| 332 | rtems_status_code can_open( const lpc176x_can_number minor, can_freq freq ) |
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| 333 | { |
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| 334 | const can_driver_entry *const can_driver = &can_driver_table[ minor ]; |
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| 335 | rtems_status_code sc = RTEMS_INVALID_NUMBER; |
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| 336 | |
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| 337 | if ( CAN_DRIVER_IS_MINOR_VALID( minor ) ) { |
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| 338 | /*Enable CAN and acceptance filter modules.*/ |
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| 339 | sc = |
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| 340 | lpc176x_module_enable( can_driver->module, LPC176X_MODULE_PCLK_DEFAULT ); |
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| 341 | RTEMS_CHECK_SC( sc, "enable can module" ); |
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| 342 | sc = lpc176x_module_enable( LPC176X_MODULE_ACCF, |
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| 343 | LPC176X_MODULE_PCLK_DEFAULT ); |
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| 344 | RTEMS_CHECK_SC( sc, "enable acceptance filter" ); |
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| 345 | /*Set pin functions.*/ |
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| 346 | setpins( minor ); |
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| 347 | |
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| 348 | can_reset( can_driver ); |
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| 349 | can_driver->device->IER = CAN_DEFAULT_INTERRUPT_CONFIGURATION; |
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| 350 | sc = can_frequency( can_driver, freq ); |
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| 351 | RTEMS_CHECK_SC( sc, "Configure CAN frequency" ); |
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| 352 | can_initialize(); |
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| 353 | |
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| 354 | acceptance_filter_device->AFMR = CAN_ACCF_AFMR_ACCBP; /*Bypass Filter.*/ |
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| 355 | } |
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| 356 | |
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| 357 | return sc; |
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| 358 | } |
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| 359 | |
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| 360 | /** |
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| 361 | * @brief Calls the installed isrs, according to the active interrupts. |
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| 362 | * |
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| 363 | * @param vector The read vector of active interrupts. |
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| 364 | * @param number The CAN device to look for interruptions. |
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| 365 | */ |
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| 366 | static inline void call_isrs( |
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| 367 | const uint32_t vector, |
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| 368 | const lpc176x_can_number number |
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| 369 | ) |
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| 370 | { |
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| 371 | can_irq_type i; |
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| 372 | |
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| 373 | for ( i = IRQ_RX; i < CAN_IRQ_NUMBER; ++i ) { |
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| 374 | if ( ( isr_vector[ i ] != NULL ) && ( vector & ( 1 << i ) ) ) |
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| 375 | isr_vector[ i ]( number ); |
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| 376 | |
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| 377 | /* else this interrupt has not been raised or it hasn't got a handler, |
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| 378 | so do nothing.*/ |
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| 379 | } |
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| 380 | } |
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| 381 | |
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| 382 | /** |
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| 383 | * @brief Checks if the passed CAN device is enabled and if it is checks for |
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| 384 | * active interrupts and calls its installed isr. |
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| 385 | * |
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| 386 | * @param number The CAN device to check for interrupts rised. |
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| 387 | */ |
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| 388 | static inline void search_and_call_int( const lpc176x_can_number number ) |
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| 389 | { |
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| 390 | const can_driver_entry *const driver = &can_driver_table[ number ]; |
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| 391 | |
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| 392 | if ( LPC176X_SCB.pconp & driver->pconp_pin ) { |
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| 393 | /*We must read the whole register at once because it resets when read.*/ |
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| 394 | const uint32_t int_vector = driver->device->ICR & CAN_INTERRUPT_TYPE_MASK; |
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| 395 | call_isrs( int_vector, number ); |
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| 396 | } |
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| 397 | |
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| 398 | /*else the device is shut down so we must do nothing.*/ |
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| 399 | } |
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| 400 | |
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| 401 | /** |
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| 402 | * @brief The standard isr to be installed for all the CAN devices. |
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| 403 | * |
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| 404 | * @param arg unused. |
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| 405 | */ |
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| 406 | static void can_isr( void *arg ) |
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| 407 | { |
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| 408 | lpc176x_can_number i; |
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| 409 | |
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| 410 | for ( i = CAN_0; i < CAN_DEVICES_NUMBER; ++i ) { |
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| 411 | search_and_call_int( i ); |
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| 412 | } |
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| 413 | } |
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| 414 | |
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| 415 | rtems_status_code can_read( |
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| 416 | const lpc176x_can_number minor, |
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| 417 | can_message *message |
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| 418 | ) |
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| 419 | { |
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| 420 | rtems_status_code sc = RTEMS_IO_ERROR; |
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| 421 | const can_driver_entry *const can_driver = &can_driver_table[ minor ]; |
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| 422 | can_device *const dev = can_driver->device; |
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| 423 | registers_can_message *const msg = &( message->registers ); |
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| 424 | |
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| 425 | can_enable( can_driver ); |
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| 426 | |
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| 427 | if ( dev->GSR & CAN_GSR_RBS_MASK ) { |
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| 428 | sc = RTEMS_SUCCESSFUL; |
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| 429 | *msg = dev->receive; |
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| 430 | dev->CMR = CAN_CMR_RRB_MASK; /* release receive buffer. */ |
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| 431 | } /* else Message not received.*/ |
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| 432 | |
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| 433 | return sc; |
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| 434 | } |
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| 435 | |
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| 436 | /** |
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| 437 | * @brief Array of masks and control bits for the transmit buffers. |
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| 438 | * It's used for each transmit buffer in order to see if it's available and to |
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| 439 | * send data to them. |
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| 440 | */ |
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| 441 | static const can_transmit_info transmit_info[ CAN_NUMBER_OF_TRANSMIT_BUFFERS ] |
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| 442 | = |
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| 443 | { |
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| 444 | { |
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| 445 | .can_status_mask = 0x00000004U, |
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| 446 | .not_cc_cmr_value = 0x21U |
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| 447 | }, |
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| 448 | { |
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| 449 | .can_status_mask = 0x00000400U, |
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| 450 | .not_cc_cmr_value = 0x41U |
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| 451 | }, |
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| 452 | { |
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| 453 | .can_status_mask = 0x00040000U, |
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| 454 | .not_cc_cmr_value = 0x81U |
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| 455 | } |
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| 456 | }; |
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| 457 | |
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| 458 | rtems_status_code can_write( |
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| 459 | const lpc176x_can_number minor, |
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| 460 | const can_message *const message |
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| 461 | ) |
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| 462 | { |
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| 463 | const can_driver_entry *const can_driver = &can_driver_table[ minor ]; |
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| 464 | can_device *const obj = can_driver->device; |
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| 465 | const uint32_t CANStatus = obj->SR; |
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| 466 | |
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| 467 | const registers_can_message *const msg = &( message->registers ); |
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| 468 | rtems_status_code sc = RTEMS_IO_ERROR; |
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| 469 | can_transmit_number transmit_buffer; |
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| 470 | |
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| 471 | can_enable( can_driver ); |
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| 472 | |
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| 473 | for ( transmit_buffer = CAN_TRANSMIT1; |
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| 474 | ( sc != RTEMS_SUCCESSFUL ) && ( transmit_buffer < |
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| 475 | CAN_NUMBER_OF_TRANSMIT_BUFFERS ); |
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| 476 | ++transmit_buffer ) { |
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| 477 | if ( CANStatus & transmit_info[ transmit_buffer ].can_status_mask ) { |
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| 478 | sc = RTEMS_SUCCESSFUL; |
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| 479 | obj->transmit[ transmit_buffer ] = *msg; |
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| 480 | obj->CMR = transmit_info[ transmit_buffer ].not_cc_cmr_value; |
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| 481 | } /*else can buffer busy, try with the next.*/ |
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| 482 | } |
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| 483 | |
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| 484 | return sc; |
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| 485 | } |
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| 486 | |
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| 487 | /** |
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| 488 | * @brief Enables the interrupt type passed to the desired CAN device. |
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| 489 | * |
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| 490 | * @param number The CAN device to enable the interrupts. |
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| 491 | * @param type The type of interrupt to enable. |
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| 492 | */ |
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| 493 | static inline void can_enable_interrupt( |
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| 494 | const lpc176x_can_number number, |
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| 495 | const can_irq_type type |
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| 496 | ) |
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| 497 | { |
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| 498 | const can_driver_entry *const driver = &can_driver_table[ number ]; |
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| 499 | const uint32_t ier = 1 << type; |
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| 500 | |
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| 501 | can_disable( driver ); |
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| 502 | driver->device->IER |= ier; |
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| 503 | can_enable( driver ); |
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| 504 | } |
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| 505 | |
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| 506 | rtems_status_code can_register_isr( |
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| 507 | const lpc176x_can_number number, |
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| 508 | const can_irq_type type, |
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| 509 | const lpc176x_can_isr isr |
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| 510 | ) |
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| 511 | { |
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| 512 | rtems_status_code sc = RTEMS_INVALID_NUMBER; |
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| 513 | |
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| 514 | if ( ( 0 <= type ) && ( type < CAN_IRQ_NUMBER ) ) { |
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| 515 | sc = RTEMS_SUCCESSFUL; |
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| 516 | isr_vector[ type ] = isr; |
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| 517 | can_enable_interrupt( number, type ); |
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| 518 | } |
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| 519 | |
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| 520 | return sc; |
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| 521 | } |
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| 522 | |
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| 523 | rtems_status_code create_can_message( |
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| 524 | can_message *const msg, |
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| 525 | const int _id, |
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| 526 | const char *const _data, |
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| 527 | const char _len |
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| 528 | ) |
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| 529 | { |
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| 530 | rtems_status_code sc = RTEMS_INVALID_NUMBER; |
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| 531 | |
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| 532 | if ( ( _len <= CAN_MAXIMUM_DATA_SIZE ) && ( _id <= CAN10_MAXIMUM_ID ) ) { |
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| 533 | sc = RTEMS_SUCCESSFUL; |
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| 534 | msg->low_level.dlc = _len; |
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| 535 | msg->low_level.type = CANStandard; |
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| 536 | msg->low_level.rtr = CANData; |
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| 537 | msg->low_level.id = _id; |
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| 538 | memcpy( msg->low_level.data, _data, _len ); |
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| 539 | } |
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| 540 | |
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| 541 | return sc; |
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| 542 | } |
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| 543 | |
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