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 const u16 *termination_const; 42 unsigned int termination_const_cnt; 43 u16 termination; 44 const u32 *bitrate_const; 45 unsigned int bitrate_const_cnt; 46 const u32 *data_bitrate_const; 47 unsigned int data_bitrate_const_cnt; 48 struct can_clock clock; 49 50 enum can_state state; 51 52 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 53 u32 ctrlmode; /* current options setting */ 54 u32 ctrlmode_supported; /* options that can be modified by netlink */ 55 u32 ctrlmode_static; /* static enabled options for driver/hardware */ 56 57 int restart_ms; 58 struct delayed_work restart_work; 59 60 int (*do_set_bittiming)(struct net_device *dev); 61 int (*do_set_data_bittiming)(struct net_device *dev); 62 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 63 int (*do_set_termination)(struct net_device *dev, u16 term); 64 int (*do_get_state)(const struct net_device *dev, 65 enum can_state *state); 66 int (*do_get_berr_counter)(const struct net_device *dev, 67 struct can_berr_counter *bec); 68 69 unsigned int echo_skb_max; 70 struct sk_buff **echo_skb; 71 72 #ifdef CONFIG_CAN_LEDS 73 struct led_trigger *tx_led_trig; 74 char tx_led_trig_name[CAN_LED_NAME_SZ]; 75 struct led_trigger *rx_led_trig; 76 char rx_led_trig_name[CAN_LED_NAME_SZ]; 77 struct led_trigger *rxtx_led_trig; 78 char rxtx_led_trig_name[CAN_LED_NAME_SZ]; 79 #endif 80 }; 81 82 /* 83 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 84 * to __u8 and ensure the dlc value to be max. 8 bytes. 85 * 86 * To be used in the CAN netdriver receive path to ensure conformance with 87 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 88 */ 89 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 90 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 91 92 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 93 static inline bool can_dropped_invalid_skb(struct net_device *dev, 94 struct sk_buff *skb) 95 { 96 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 97 98 if (skb->protocol == htons(ETH_P_CAN)) { 99 if (unlikely(skb->len != CAN_MTU || 100 cfd->len > CAN_MAX_DLEN)) 101 goto inval_skb; 102 } else if (skb->protocol == htons(ETH_P_CANFD)) { 103 if (unlikely(skb->len != CANFD_MTU || 104 cfd->len > CANFD_MAX_DLEN)) 105 goto inval_skb; 106 } else 107 goto inval_skb; 108 109 return false; 110 111 inval_skb: 112 kfree_skb(skb); 113 dev->stats.tx_dropped++; 114 return true; 115 } 116 117 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 118 { 119 /* the CAN specific type of skb is identified by its data length */ 120 return skb->len == CANFD_MTU; 121 } 122 123 /* helper to define static CAN controller features at device creation time */ 124 static inline void can_set_static_ctrlmode(struct net_device *dev, 125 u32 static_mode) 126 { 127 struct can_priv *priv = netdev_priv(dev); 128 129 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 130 priv->ctrlmode = static_mode; 131 priv->ctrlmode_static = static_mode; 132 133 /* override MTU which was set by default in can_setup()? */ 134 if (static_mode & CAN_CTRLMODE_FD) 135 dev->mtu = CANFD_MTU; 136 } 137 138 /* get data length from can_dlc with sanitized can_dlc */ 139 u8 can_dlc2len(u8 can_dlc); 140 141 /* map the sanitized data length to an appropriate data length code */ 142 u8 can_len2dlc(u8 len); 143 144 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 145 void free_candev(struct net_device *dev); 146 147 /* a candev safe wrapper around netdev_priv */ 148 struct can_priv *safe_candev_priv(struct net_device *dev); 149 150 int open_candev(struct net_device *dev); 151 void close_candev(struct net_device *dev); 152 int can_change_mtu(struct net_device *dev, int new_mtu); 153 154 int register_candev(struct net_device *dev); 155 void unregister_candev(struct net_device *dev); 156 157 int can_restart_now(struct net_device *dev); 158 void can_bus_off(struct net_device *dev); 159 160 void can_change_state(struct net_device *dev, struct can_frame *cf, 161 enum can_state tx_state, enum can_state rx_state); 162 163 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 164 unsigned int idx); 165 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 166 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 167 168 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 169 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 170 struct canfd_frame **cfd); 171 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 172 struct can_frame **cf); 173 174 #endif /* !_CAN_DEV_H */ 175