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 net_device *dev; 36 struct can_device_stats can_stats; 37 38 struct can_bittiming bittiming, data_bittiming; 39 const struct can_bittiming_const *bittiming_const, 40 *data_bittiming_const; 41 struct can_clock clock; 42 43 enum can_state state; 44 45 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 46 u32 ctrlmode; /* current options setting */ 47 u32 ctrlmode_supported; /* options that can be modified by netlink */ 48 u32 ctrlmode_static; /* static enabled options for driver/hardware */ 49 50 int restart_ms; 51 struct delayed_work restart_work; 52 53 int (*do_set_bittiming)(struct net_device *dev); 54 int (*do_set_data_bittiming)(struct net_device *dev); 55 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 56 int (*do_get_state)(const struct net_device *dev, 57 enum can_state *state); 58 int (*do_get_berr_counter)(const struct net_device *dev, 59 struct can_berr_counter *bec); 60 61 unsigned int echo_skb_max; 62 struct sk_buff **echo_skb; 63 64 #ifdef CONFIG_CAN_LEDS 65 struct led_trigger *tx_led_trig; 66 char tx_led_trig_name[CAN_LED_NAME_SZ]; 67 struct led_trigger *rx_led_trig; 68 char rx_led_trig_name[CAN_LED_NAME_SZ]; 69 struct led_trigger *rxtx_led_trig; 70 char rxtx_led_trig_name[CAN_LED_NAME_SZ]; 71 #endif 72 }; 73 74 /* 75 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 76 * to __u8 and ensure the dlc value to be max. 8 bytes. 77 * 78 * To be used in the CAN netdriver receive path to ensure conformance with 79 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 80 */ 81 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 82 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 83 84 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 85 static inline bool can_dropped_invalid_skb(struct net_device *dev, 86 struct sk_buff *skb) 87 { 88 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 89 90 if (skb->protocol == htons(ETH_P_CAN)) { 91 if (unlikely(skb->len != CAN_MTU || 92 cfd->len > CAN_MAX_DLEN)) 93 goto inval_skb; 94 } else if (skb->protocol == htons(ETH_P_CANFD)) { 95 if (unlikely(skb->len != CANFD_MTU || 96 cfd->len > CANFD_MAX_DLEN)) 97 goto inval_skb; 98 } else 99 goto inval_skb; 100 101 return false; 102 103 inval_skb: 104 kfree_skb(skb); 105 dev->stats.tx_dropped++; 106 return true; 107 } 108 109 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 110 { 111 /* the CAN specific type of skb is identified by its data length */ 112 return skb->len == CANFD_MTU; 113 } 114 115 /* helper to define static CAN controller features at device creation time */ 116 static inline void can_set_static_ctrlmode(struct net_device *dev, 117 u32 static_mode) 118 { 119 struct can_priv *priv = netdev_priv(dev); 120 121 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 122 priv->ctrlmode = static_mode; 123 priv->ctrlmode_static = static_mode; 124 125 /* override MTU which was set by default in can_setup()? */ 126 if (static_mode & CAN_CTRLMODE_FD) 127 dev->mtu = CANFD_MTU; 128 } 129 130 /* get data length from can_dlc with sanitized can_dlc */ 131 u8 can_dlc2len(u8 can_dlc); 132 133 /* map the sanitized data length to an appropriate data length code */ 134 u8 can_len2dlc(u8 len); 135 136 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 137 void free_candev(struct net_device *dev); 138 139 /* a candev safe wrapper around netdev_priv */ 140 struct can_priv *safe_candev_priv(struct net_device *dev); 141 142 int open_candev(struct net_device *dev); 143 void close_candev(struct net_device *dev); 144 int can_change_mtu(struct net_device *dev, int new_mtu); 145 146 int register_candev(struct net_device *dev); 147 void unregister_candev(struct net_device *dev); 148 149 int can_restart_now(struct net_device *dev); 150 void can_bus_off(struct net_device *dev); 151 152 void can_change_state(struct net_device *dev, struct can_frame *cf, 153 enum can_state tx_state, enum can_state rx_state); 154 155 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 156 unsigned int idx); 157 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 158 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 159 160 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 161 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 162 struct canfd_frame **cfd); 163 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 164 struct can_frame **cf); 165 166 #endif /* !_CAN_DEV_H */ 167