1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * linux/can/dev.h 4 * 5 * Definitions for the CAN network device driver interface 6 * 7 * Copyright (C) 2006 Andrey Volkov <[email protected]> 8 * Varma Electronics Oy 9 * 10 * Copyright (C) 2008 Wolfgang Grandegger <[email protected]> 11 * 12 */ 13 14 #ifndef _CAN_DEV_H 15 #define _CAN_DEV_H 16 17 #include <linux/can.h> 18 #include <linux/can/error.h> 19 #include <linux/can/led.h> 20 #include <linux/can/netlink.h> 21 #include <linux/netdevice.h> 22 23 /* 24 * CAN mode 25 */ 26 enum can_mode { 27 CAN_MODE_STOP = 0, 28 CAN_MODE_START, 29 CAN_MODE_SLEEP 30 }; 31 32 /* 33 * CAN common private data 34 */ 35 struct can_priv { 36 struct net_device *dev; 37 struct can_device_stats can_stats; 38 39 struct can_bittiming bittiming, data_bittiming; 40 const struct can_bittiming_const *bittiming_const, 41 *data_bittiming_const; 42 const u16 *termination_const; 43 unsigned int termination_const_cnt; 44 u16 termination; 45 const u32 *bitrate_const; 46 unsigned int bitrate_const_cnt; 47 const u32 *data_bitrate_const; 48 unsigned int data_bitrate_const_cnt; 49 struct can_clock clock; 50 51 enum can_state state; 52 53 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 54 u32 ctrlmode; /* current options setting */ 55 u32 ctrlmode_supported; /* options that can be modified by netlink */ 56 u32 ctrlmode_static; /* static enabled options for driver/hardware */ 57 58 int restart_ms; 59 struct delayed_work restart_work; 60 61 int (*do_set_bittiming)(struct net_device *dev); 62 int (*do_set_data_bittiming)(struct net_device *dev); 63 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 64 int (*do_set_termination)(struct net_device *dev, u16 term); 65 int (*do_get_state)(const struct net_device *dev, 66 enum can_state *state); 67 int (*do_get_berr_counter)(const struct net_device *dev, 68 struct can_berr_counter *bec); 69 70 unsigned int echo_skb_max; 71 struct sk_buff **echo_skb; 72 73 #ifdef CONFIG_CAN_LEDS 74 struct led_trigger *tx_led_trig; 75 char tx_led_trig_name[CAN_LED_NAME_SZ]; 76 struct led_trigger *rx_led_trig; 77 char rx_led_trig_name[CAN_LED_NAME_SZ]; 78 struct led_trigger *rxtx_led_trig; 79 char rxtx_led_trig_name[CAN_LED_NAME_SZ]; 80 #endif 81 }; 82 83 /* 84 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 85 * to __u8 and ensure the dlc value to be max. 8 bytes. 86 * 87 * To be used in the CAN netdriver receive path to ensure conformance with 88 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 89 */ 90 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 91 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 92 93 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 94 static inline bool can_dropped_invalid_skb(struct net_device *dev, 95 struct sk_buff *skb) 96 { 97 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 98 99 if (skb->protocol == htons(ETH_P_CAN)) { 100 if (unlikely(skb->len != CAN_MTU || 101 cfd->len > CAN_MAX_DLEN)) 102 goto inval_skb; 103 } else if (skb->protocol == htons(ETH_P_CANFD)) { 104 if (unlikely(skb->len != CANFD_MTU || 105 cfd->len > CANFD_MAX_DLEN)) 106 goto inval_skb; 107 } else 108 goto inval_skb; 109 110 return false; 111 112 inval_skb: 113 kfree_skb(skb); 114 dev->stats.tx_dropped++; 115 return true; 116 } 117 118 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 119 { 120 /* the CAN specific type of skb is identified by its data length */ 121 return skb->len == CANFD_MTU; 122 } 123 124 /* helper to define static CAN controller features at device creation time */ 125 static inline void can_set_static_ctrlmode(struct net_device *dev, 126 u32 static_mode) 127 { 128 struct can_priv *priv = netdev_priv(dev); 129 130 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 131 priv->ctrlmode = static_mode; 132 priv->ctrlmode_static = static_mode; 133 134 /* override MTU which was set by default in can_setup()? */ 135 if (static_mode & CAN_CTRLMODE_FD) 136 dev->mtu = CANFD_MTU; 137 } 138 139 /* get data length from can_dlc with sanitized can_dlc */ 140 u8 can_dlc2len(u8 can_dlc); 141 142 /* map the sanitized data length to an appropriate data length code */ 143 u8 can_len2dlc(u8 len); 144 145 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max); 146 void free_candev(struct net_device *dev); 147 148 /* a candev safe wrapper around netdev_priv */ 149 struct can_priv *safe_candev_priv(struct net_device *dev); 150 151 int open_candev(struct net_device *dev); 152 void close_candev(struct net_device *dev); 153 int can_change_mtu(struct net_device *dev, int new_mtu); 154 155 int register_candev(struct net_device *dev); 156 void unregister_candev(struct net_device *dev); 157 158 int can_restart_now(struct net_device *dev); 159 void can_bus_off(struct net_device *dev); 160 161 void can_change_state(struct net_device *dev, struct can_frame *cf, 162 enum can_state tx_state, enum can_state rx_state); 163 164 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 165 unsigned int idx); 166 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 167 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 168 169 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 170 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 171 struct canfd_frame **cfd); 172 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 173 struct can_frame **cf); 174 175 #endif /* !_CAN_DEV_H */ 176