1 files changed, 284 insertions, 0 deletions
diff --git a/cpukit/include/dev/can/can.h b/cpukit/include/dev/can/can.h
new file mode 100644
index 0000000000..9e55395039
--- /dev/null
+++ b/cpukit/include/dev/can/can.h
@@ -0,0 +1,284 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup CANBus
+ *
+ * @brief Controller Area Network (CAN) Bus Implementation
+ *
+ */
+
+/*
+ * Copyright (C) 2022 Prashanth S (fishesprashanth@gmail.com)
+ *
+ * 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.
+ *
+ * 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 _DEV_CAN_CAN_H
+#define _DEV_CAN_CAN_H
+
+#include <rtems/imfs.h>
+#include <rtems/thread.h>
+#include <semaphore.h>
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <dev/can/can-msg.h>
+
+#define DEBUG(str, ...)                                                   \
+    do {                                                                      \
+      printf("CAN: %s:%d ID: %08X ", __FILE__, __LINE__, rtems_task_self());  \
+      printf(str, ##__VA_ARGS__);                                             \
+    } while (false);
+
+#define CAN_DEBUG(str, ...) DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_BUF(str, ...) CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_ISR(str, ...) CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_LOCK(str, ...) CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_RX(str, ...) CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_TX(str, ...) CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_DEBUG_REG(str, ...) //CAN_DEBUG(str, ##__VA_ARGS__)
+#define CAN_ERR(str, ...) DEBUG(str, ##__VA_ARGS__)
+
+#define CAN_MSG_LEN(msg) ((char *)(&((struct can_msg *)msg)->data[(uint16_t)((struct can_msg *)msg)->len]) - (char *)(msg))
+
+/* Maximum Bus Reg (255) */
+#define CAN_BUS_REG_MAX (255)
+
+/**
+ * @defgroup Controller Area Network (CAN) Driver
+ *
+ * @ingroup RTEMSDeviceDrivers
+ *
+ * @brief Controller Area Network (CAN) bus and device driver support.
+ *
+ * @{
+ */
+
+/**
+ * @defgroup CANBus CAN Bus Driver
+ *
+ * @ingroup CAN
+ *
+ * @{
+ */
+
+/**
+ * @brief CAN tx fifo data structure.
+ */
+struct ring_buf {
+ /**
+   * @brief Pointer to array of can_msg structure.
+   */
+  struct can_msg *pbuf;
+ /**
+   * @brief Index of the next free buffer.
+   */
+  uint32_t head;
+ /**
+   * @brief Index of the produced buffer.
+   */
+  uint32_t tail;
+  /**
+   * @brief Number of empty buffers.
+   */
+  uint32_t empty_count;
+};
+
+/**
+ * @brief CAN Controller device specific operations.
+ * These function pointers are initialized by the CAN device driver while
+ * registering (can_bus_register).
+ */
+typedef struct can_dev_ops {
+  /**
+   * @brief Transfers CAN messages to device fifo.
+   *
+   * @param[in] priv device control structure.
+   * @param[in] msg can_msg message structure.
+   *
+   * @retval 0 Successful operation.
+   * @retval >0 error number in case of an error.
+   */
+  int32_t (*dev_tx)(void *priv, struct can_msg *msg);
+  /**
+   * @brief Check device is ready to transfer a CAN message
+   *
+   * @param[in] priv device control structure.
+   *
+   * @retval true device ready.
+   * @retval false device not ready.
+   */
+  bool (*dev_tx_ready)(void *priv);
+  /**
+   * @brief Enable/Disable CAN interrupts.
+   *
+   * @param[in] priv device control structure.
+   * @param[in] flag true/false to Enable/Disable CAN interrupts.
+   *
+   */
+  void (*dev_int)(void *priv, bool flag);
+  /**
+   * @brief CAN device specific I/O controls.
+   *
+   * @param[in] priv device control structure.
+   * @param[in] buffer This depends on the cmd.
+   * @param[in] cmd Device specific I/O commands.
+   *
+   * @retval 0 Depends on the cmd.
+   */
+  int32_t (*dev_ioctl)(void *priv, void *buffer, size_t cmd);
+} can_dev_ops;
+
+/**
+ * @name CAN bus control
+ *
+ * @{
+ */
+
+/**
+ * @brief Obtains the bus.
+ *
+ * This command has no argument.
+ */
+typedef struct can_bus {
+ /**
+   * @brief Device specific control.
+   */
+  void *priv;
+ /**
+   * @brief Device controller index.
+   */
+  uint8_t index;
+ /**
+   * @brief Device specific operations.
+   */
+  struct can_dev_ops *can_dev_ops;
+ /**
+   * @brief tx fifo.
+   */
+  struct ring_buf tx_fifo;
+ /**
+   * @brief Counting semaphore id (for fifo sync).
+   */
+  rtems_id tx_fifo_sem_id;
+
+ /* FIXME: Using only one CAN msg buffer, Should create a ring buffer */
+ /**
+   * @brief rx fifo.
+   */
+  struct can_msg can_rx_msg;
+ /**
+   * @brief Mutex to handle bus concurrency.
+   */
+  rtems_mutex mutex;
+  /**
+   * @brief Destroys the bus.
+   *
+   * @param[in] bus control structure.
+   */
+  void (*destroy)(struct can_bus *bus);
+#ifdef CAN_DEBUG_LOCK
+
+ /**
+   * @brief For debugging semaphore obtain/release.
+   */
+  int sem_count;
+
+#endif /* CAN_DEBUG_LOCK */
+
+} can_bus;
+
+/** @} */
+
+/**
+ * @brief Register a CAN node with the CAN bus driver.
+ *
+ * @param[in] bus bus control structure.
+ * @param[in] bus_path path of device node.
+ *
+ * @retval >=0 rtems status.
+ */
+rtems_status_code can_bus_register(can_bus *bus, const char *bus_path);
+
+/**
+ * @brief Allocate and initilaize bus control structure.
+ *
+ * @param[in] size Size of the bus control structure.
+ *
+ * @retval NULL No memory available.
+ * @retval Address Pointer to the allocated bus control structure.
+ */
+can_bus *can_bus_alloc_and_init(size_t size);
+
+/**
+ * @brief initilaize bus control structure.
+ *
+ * @param[in] bus bus control structure.
+ *
+ * @retval 0 success.
+ * @retval >0 error number.
+ */
+int can_bus_init(can_bus *bus);
+
+/**
+ * @brief Initiates CAN message transfer.
+ * 
+ * Should be called with CAN interrupt disabled.
+ *
+ * @param[in] bus Bus control structure.
+ *
+ * @retval 0 success.
+ * @retval >0 error number.
+ */
+int can_tx_done(struct can_bus *bus);
+
+/**
+ * @brief Sends the received CAN message to the application.
+ * 
+ * Should be called by the device when CAN message should be sent to applicaiton.
+ * Should be called only with CAN interrupts disabled.
+ *
+ * @param[in] bus bus control structure.
+ * @param[in] msg can_msg structure.
+ *
+ * @retval 0 success.
+ * @retval >0 error number.
+ */
+int can_receive(struct can_bus *bus, struct can_msg *msg);
+
+/**
+ * @brief Prints the can_msg values pointed by msg.
+ * 
+ * @param[in] msg can_msg structure.
+ *
+ */
+void can_print_msg(struct can_msg const *msg);
+
+/** @} */  /* end of CAN device driver */
+
+/** @} */
+
+#endif /* _DEV_CAN_CAN_H */