1 /* 2 * linux/can/dev.h 3 * 4 * Definitions for the CAN network device driver interface 5 * 6 * Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com> 7 * Varma Electronics Oy 8 * 9 * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com> 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 #include <linux/can/led.h> 20 21 /* 22 * CAN mode 23 */ 24 enum can_mode { 25 CAN_MODE_STOP = 0, 26 CAN_MODE_START, 27 CAN_MODE_SLEEP 28 }; 29 30 /* 31 * CAN common private data 32 */ 33 struct can_priv { 34 struct can_device_stats can_stats; 35 36 struct can_bittiming bittiming, data_bittiming; 37 const struct can_bittiming_const *bittiming_const, 38 *data_bittiming_const; 39 struct can_clock clock; 40 41 enum can_state state; 42 u32 ctrlmode; 43 u32 ctrlmode_supported; 44 45 int restart_ms; 46 struct timer_list restart_timer; 47 48 int (*do_set_bittiming)(struct net_device *dev); 49 int (*do_set_data_bittiming)(struct net_device *dev); 50 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 51 int (*do_get_state)(const struct net_device *dev, 52 enum can_state *state); 53 int (*do_get_berr_counter)(const struct net_device *dev, 54 struct can_berr_counter *bec); 55 56 unsigned int echo_skb_max; 57 struct sk_buff **echo_skb; 58 59 #ifdef CONFIG_CAN_LEDS 60 struct led_trigger *tx_led_trig; 61 char tx_led_trig_name[CAN_LED_NAME_SZ]; 62 struct led_trigger *rx_led_trig; 63 char rx_led_trig_name[CAN_LED_NAME_SZ]; 64 #endif 65 }; 66 67 /* 68 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 69 * to __u8 and ensure the dlc value to be max. 8 bytes. 70 * 71 * To be used in the CAN netdriver receive path to ensure conformance with 72 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 73 */ 74 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 75 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 76 77 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 78 static inline int can_dropped_invalid_skb(struct net_device *dev, 79 struct sk_buff *skb) 80 { 81 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 82 83 if (skb->protocol == htons(ETH_P_CAN)) { 84 if (unlikely(skb->len != CAN_MTU || 85 cfd->len > CAN_MAX_DLEN)) 86 goto inval_skb; 87 } else if (skb->protocol == htons(ETH_P_CANFD)) { 88 if (unlikely(skb->len != CANFD_MTU || 89 cfd->len > CANFD_MAX_DLEN)) 90 goto inval_skb; 91 } else 92 goto inval_skb; 93 94 return 0; 95 96 inval_skb: 97 kfree_skb(skb); 98 dev->stats.tx_dropped++; 99 return 1; 100 } 101 102 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 103 { 104 /* the CAN specific type of skb is identified by its data length */ 105 return skb->len == CANFD_MTU; 106 } 107 108 /* get data length from can_dlc with sanitized can_dlc */ 109 u8 can_dlc2len(u8 can_dlc); 110 111 /* map the sanitized data length to an appropriate data length code */ 112 u8 can_len2dlc(u8 len); 113 114 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 115 void free_candev(struct net_device *dev); 116 117 /* a candev safe wrapper around netdev_priv */ 118 struct can_priv *safe_candev_priv(struct net_device *dev); 119 120 int open_candev(struct net_device *dev); 121 void close_candev(struct net_device *dev); 122 int can_change_mtu(struct net_device *dev, int new_mtu); 123 124 int register_candev(struct net_device *dev); 125 void unregister_candev(struct net_device *dev); 126 127 int can_restart_now(struct net_device *dev); 128 void can_bus_off(struct net_device *dev); 129 130 void can_change_state(struct net_device *dev, struct can_frame *cf, 131 enum can_state tx_state, enum can_state rx_state); 132 133 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 134 unsigned int idx); 135 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 136 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 137 138 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 139 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 140 struct canfd_frame **cfd); 141 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 142 struct can_frame **cf); 143 144 #endif /* !_CAN_DEV_H */ 145