1 /* 2 * linux/can/dev.h 3 * 4 * Definitions for the CAN network device driver interface 5 * 6 * Copyright (C) 2006 Andrey Volkov <[email protected]> 7 * Varma Electronics Oy 8 * 9 * Copyright (C) 2008 Wolfgang Grandegger <[email protected]> 10 * 11 */ 12 13 #ifndef CAN_DEV_H 14 #define CAN_DEV_H 15 16 #include <linux/can.h> 17 #include <linux/can/netlink.h> 18 #include <linux/can/error.h> 19 20 /* 21 * CAN mode 22 */ 23 enum can_mode { 24 CAN_MODE_STOP = 0, 25 CAN_MODE_START, 26 CAN_MODE_SLEEP 27 }; 28 29 /* 30 * CAN common private data 31 */ 32 struct can_priv { 33 struct can_device_stats can_stats; 34 35 struct can_bittiming bittiming; 36 const struct can_bittiming_const *bittiming_const; 37 struct can_clock clock; 38 39 enum can_state state; 40 u32 ctrlmode; 41 u32 ctrlmode_supported; 42 43 int restart_ms; 44 struct timer_list restart_timer; 45 46 int (*do_set_bittiming)(struct net_device *dev); 47 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 48 int (*do_get_state)(const struct net_device *dev, 49 enum can_state *state); 50 int (*do_get_berr_counter)(const struct net_device *dev, 51 struct can_berr_counter *bec); 52 53 unsigned int echo_skb_max; 54 struct sk_buff **echo_skb; 55 }; 56 57 /* 58 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 59 * to __u8 and ensure the dlc value to be max. 8 bytes. 60 * 61 * To be used in the CAN netdriver receive path to ensure conformance with 62 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 63 */ 64 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 65 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 66 67 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 68 static inline int can_dropped_invalid_skb(struct net_device *dev, 69 struct sk_buff *skb) 70 { 71 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 72 73 if (skb->protocol == htons(ETH_P_CAN)) { 74 if (unlikely(skb->len != CAN_MTU || 75 cfd->len > CAN_MAX_DLEN)) 76 goto inval_skb; 77 } else if (skb->protocol == htons(ETH_P_CANFD)) { 78 if (unlikely(skb->len != CANFD_MTU || 79 cfd->len > CANFD_MAX_DLEN)) 80 goto inval_skb; 81 } else 82 goto inval_skb; 83 84 return 0; 85 86 inval_skb: 87 kfree_skb(skb); 88 dev->stats.tx_dropped++; 89 return 1; 90 } 91 92 /* get data length from can_dlc with sanitized can_dlc */ 93 u8 can_dlc2len(u8 can_dlc); 94 95 /* map the sanitized data length to an appropriate data length code */ 96 u8 can_len2dlc(u8 len); 97 98 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 99 void free_candev(struct net_device *dev); 100 101 int open_candev(struct net_device *dev); 102 void close_candev(struct net_device *dev); 103 104 int register_candev(struct net_device *dev); 105 void unregister_candev(struct net_device *dev); 106 107 int can_restart_now(struct net_device *dev); 108 void can_bus_off(struct net_device *dev); 109 110 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 111 unsigned int idx); 112 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 113 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 114 115 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 116 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 117 struct can_frame **cf); 118 119 #endif /* CAN_DEV_H */ 120