[DM/CAN] Update CAN for DM

components/drivers/can/Kconfig

@@ -1,4 +1,4 @@
-config RT_USING_CAN
+menuconfig RT_USING_CAN
     bool "Using CAN device drivers"
     default n
     help
@@ -73,4 +73,8 @@ if RT_USING_CAN
             consumes static RAM but guarantees the memory is always available
             and avoids heap fragmentation.
 
-endif
+endif
+
+if RT_USING_DM && RT_USING_CAN
+    osource "$(SOC_DM_CAN_DIR)/Kconfig"
+endif

components/drivers/can/SConscript

@@ -3,6 +3,10 @@ from building import *
 cwd     = GetCurrentDir()
 src     = Glob('*.c')
 CPPPATH = [cwd + '/../include']
+
+if not GetDepend('RT_USING_DM'):
+    SrcRemove(src, ['can_dm.c'])
+
 group   = DefineGroup('DeviceDrivers', src, depend = ['RT_USING_CAN'], CPPPATH = CPPPATH)
 
 Return('group')

components/drivers/can/can_dm.c

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2006-2022, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2022-11-26     GuEe-GUI     first version
+ */
+
+#include "can_dm.h"
+
+static const rt_uint8_t dlc2len[] =
+{
+    0, 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 20, 24, 32, 48, 64
+};
+
+rt_uint8_t can_dlc2len(rt_uint8_t can_dlc)
+{
+    return dlc2len[can_dlc & 0x0F];
+}
+
+static const rt_uint8_t len2dlc[] =
+{
+    0, 1, 2, 3, 4, 5, 6, 7, 8,      /* 0 - 8 */
+    9, 9, 9, 9,                     /* 9 - 12 */
+    10, 10, 10, 10,                 /* 13 - 16 */
+    11, 11, 11, 11,                 /* 17 - 20 */
+    12, 12, 12, 12,                 /* 21 - 24 */
+    13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
+    14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
+    14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
+    15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
+    15, 15, 15, 15, 15, 15, 15, 15, /* 57 - 64 */
+};
+
+rt_uint8_t can_len2dlc(rt_uint8_t len)
+{
+    if (len <= 64)
+    {
+        return len2dlc[len];
+    }
+
+    return 0xf;
+}

components/drivers/can/can_dm.h

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2006-2022, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2022-11-26     GuEe-GUI     first version
+ */
+
+#ifndef __CAN_DM_H__
+#define __CAN_DM_H__
+
+#include <drivers/misc.h>
+
+/* Special address description flags for the CAN_ID */
+#define CAN_EFF_FLAG        0x80000000U     /* EFF/SFF is set in the MSB */
+#define CAN_RTR_FLAG        0x40000000U     /* Remote transmission request */
+#define CAN_ERR_FLAG        0x20000000U     /* Error message frame */
+
+/* Valid bits in CAN ID for frame formats */
+#define CAN_SFF_MASK        0x000007ffU     /* Standard frame format (SFF) */
+#define CAN_EFF_MASK        0x1fffffffU     /* Extended frame format (EFF) */
+#define CAN_ERR_MASK        0x1fffffffU     /* Omit EFF, RTR, ERR flags */
+#define CANXL_PRIO_MASK     CAN_SFF_MASK    /* 11 bit priority mask */
+
+/* CAN payload length and DLC definitions according to ISO 11898-1 */
+#define CAN_MAX_DLC         8
+#define CAN_MAX_RAW_DLC     15
+#define CAN_MAX_DLEN        8
+
+/* CAN FD payload length and DLC definitions according to ISO 11898-7 */
+#define CANFD_MAX_DLC       15
+#define CANFD_MAX_DLEN      64
+
+/*
+ * To be used in the CAN netdriver receive path to ensure conformance with
+ * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
+ */
+#define can_get_dlc(v)      (rt_min_t(rt_uint8_t, (v), CAN_MAX_DLC))
+#define canfd_get_dlc(v)    (rt_min_t(rt_uint8_t, (v), CANFD_MAX_DLC))
+
+/**
+ * @brief Convert CAN DLC value to actual data length
+ *
+ * Converts a CAN Data Length Code (DLC) to the actual number of data bytes
+ * according to ISO 11898-1 and ISO 11898-7 (CAN FD) specifications.
+ *
+ * @param can_dlc The DLC value (0-15)
+ * @return The actual data length in bytes
+ */
+rt_uint8_t can_dlc2len(rt_uint8_t can_dlc);
+
+/**
+ * @brief Convert data length to CAN DLC value
+ *
+ * Converts a data length in bytes to the appropriate CAN Data Length Code (DLC)
+ * according to ISO 11898-1 and ISO 11898-7 (CAN FD) specifications.
+ *
+ * @param len The data length in bytes (0-64)
+ * @return The corresponding DLC value (0-15)
+ */
+rt_uint8_t can_len2dlc(rt_uint8_t len);
+
+#endif /* __CAN_DM_H__ */