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/error.h> 18 #include <linux/can/led.h> 19 #include <linux/can/netlink.h> 20 #include <linux/netdevice.h> 21 22 /* 23 * CAN mode 24 */ 25 enum can_mode { 26 CAN_MODE_STOP = 0, 27 CAN_MODE_START, 28 CAN_MODE_SLEEP 29 }; 30 31 /* 32 * CAN common private data 33 */ 34 struct can_priv { 35 struct can_device_stats can_stats; 36 37 struct can_bittiming bittiming, data_bittiming; 38 const struct can_bittiming_const *bittiming_const, 39 *data_bittiming_const; 40 struct can_clock clock; 41 42 enum can_state state; 43 44 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 45 u32 ctrlmode; /* current options setting */ 46 u32 ctrlmode_supported; /* options that can be modified by netlink */ 47 u32 ctrlmode_static; /* static enabled options for driver/hardware */ 48 49 int restart_ms; 50 struct timer_list restart_timer; 51 52 int (*do_set_bittiming)(struct net_device *dev); 53 int (*do_set_data_bittiming)(struct net_device *dev); 54 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 55 int (*do_get_state)(const struct net_device *dev, 56 enum can_state *state); 57 int (*do_get_berr_counter)(const struct net_device *dev, 58 struct can_berr_counter *bec); 59 60 unsigned int echo_skb_max; 61 struct sk_buff **echo_skb; 62 63 #ifdef CONFIG_CAN_LEDS 64 struct led_trigger *tx_led_trig; 65 char tx_led_trig_name[CAN_LED_NAME_SZ]; 66 struct led_trigger *rx_led_trig; 67 char rx_led_trig_name[CAN_LED_NAME_SZ]; 68 struct led_trigger *rxtx_led_trig; 69 char rxtx_led_trig_name[CAN_LED_NAME_SZ]; 70 #endif 71 }; 72 73 /* 74 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 75 * to __u8 and ensure the dlc value to be max. 8 bytes. 76 * 77 * To be used in the CAN netdriver receive path to ensure conformance with 78 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 79 */ 80 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 81 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 82 83 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 84 static inline bool can_dropped_invalid_skb(struct net_device *dev, 85 struct sk_buff *skb) 86 { 87 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 88 89 if (skb->protocol == htons(ETH_P_CAN)) { 90 if (unlikely(skb->len != CAN_MTU || 91 cfd->len > CAN_MAX_DLEN)) 92 goto inval_skb; 93 } else if (skb->protocol == htons(ETH_P_CANFD)) { 94 if (unlikely(skb->len != CANFD_MTU || 95 cfd->len > CANFD_MAX_DLEN)) 96 goto inval_skb; 97 } else 98 goto inval_skb; 99 100 return false; 101 102 inval_skb: 103 kfree_skb(skb); 104 dev->stats.tx_dropped++; 105 return true; 106 } 107 108 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 109 { 110 /* the CAN specific type of skb is identified by its data length */ 111 return skb->len == CANFD_MTU; 112 } 113 114 /* helper to define static CAN controller features at device creation time */ 115 static inline void can_set_static_ctrlmode(struct net_device *dev, 116 u32 static_mode) 117 { 118 struct can_priv *priv = netdev_priv(dev); 119 120 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 121 priv->ctrlmode = static_mode; 122 priv->ctrlmode_static = static_mode; 123 124 /* override MTU which was set by default in can_setup()? */ 125 if (static_mode & CAN_CTRLMODE_FD) 126 dev->mtu = CANFD_MTU; 127 } 128 129 /* get data length from can_dlc with sanitized can_dlc */ 130 u8 can_dlc2len(u8 can_dlc); 131 132 /* map the sanitized data length to an appropriate data length code */ 133 u8 can_len2dlc(u8 len); 134 135 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 136 void free_candev(struct net_device *dev); 137 138 /* a candev safe wrapper around netdev_priv */ 139 struct can_priv *safe_candev_priv(struct net_device *dev); 140 141 int open_candev(struct net_device *dev); 142 void close_candev(struct net_device *dev); 143 int can_change_mtu(struct net_device *dev, int new_mtu); 144 145 int register_candev(struct net_device *dev); 146 void unregister_candev(struct net_device *dev); 147 148 int can_restart_now(struct net_device *dev); 149 void can_bus_off(struct net_device *dev); 150 151 void can_change_state(struct net_device *dev, struct can_frame *cf, 152 enum can_state tx_state, enum can_state rx_state); 153 154 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 155 unsigned int idx); 156 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 157 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 158 159 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 160 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 161 struct canfd_frame **cfd); 162 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 163 struct can_frame **cf); 164 165 #endif /* !_CAN_DEV_H */ 166