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 <avolkov@varma-el.com> 8 * Varma Electronics Oy 9 * 10 * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com> 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 u32 bitrate_max; 50 struct can_clock clock; 51 52 enum can_state state; 53 54 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 55 u32 ctrlmode; /* current options setting */ 56 u32 ctrlmode_supported; /* options that can be modified by netlink */ 57 u32 ctrlmode_static; /* static enabled options for driver/hardware */ 58 59 int restart_ms; 60 struct delayed_work restart_work; 61 62 int (*do_set_bittiming)(struct net_device *dev); 63 int (*do_set_data_bittiming)(struct net_device *dev); 64 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 65 int (*do_set_termination)(struct net_device *dev, u16 term); 66 int (*do_get_state)(const struct net_device *dev, 67 enum can_state *state); 68 int (*do_get_berr_counter)(const struct net_device *dev, 69 struct can_berr_counter *bec); 70 71 unsigned int echo_skb_max; 72 struct sk_buff **echo_skb; 73 74 #ifdef CONFIG_CAN_LEDS 75 struct led_trigger *tx_led_trig; 76 char tx_led_trig_name[CAN_LED_NAME_SZ]; 77 struct led_trigger *rx_led_trig; 78 char rx_led_trig_name[CAN_LED_NAME_SZ]; 79 struct led_trigger *rxtx_led_trig; 80 char rxtx_led_trig_name[CAN_LED_NAME_SZ]; 81 #endif 82 }; 83 84 /* 85 * get_can_dlc(value) - helper macro to cast a given data length code (dlc) 86 * to __u8 and ensure the dlc value to be max. 8 bytes. 87 * 88 * To be used in the CAN netdriver receive path to ensure conformance with 89 * ISO 11898-1 Chapter 8.4.2.3 (DLC field) 90 */ 91 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC)) 92 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC)) 93 94 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */ 95 static inline bool can_dropped_invalid_skb(struct net_device *dev, 96 struct sk_buff *skb) 97 { 98 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data; 99 100 if (skb->protocol == htons(ETH_P_CAN)) { 101 if (unlikely(skb->len != CAN_MTU || 102 cfd->len > CAN_MAX_DLEN)) 103 goto inval_skb; 104 } else if (skb->protocol == htons(ETH_P_CANFD)) { 105 if (unlikely(skb->len != CANFD_MTU || 106 cfd->len > CANFD_MAX_DLEN)) 107 goto inval_skb; 108 } else 109 goto inval_skb; 110 111 return false; 112 113 inval_skb: 114 kfree_skb(skb); 115 dev->stats.tx_dropped++; 116 return true; 117 } 118 119 static inline bool can_is_canfd_skb(const struct sk_buff *skb) 120 { 121 /* the CAN specific type of skb is identified by its data length */ 122 return skb->len == CANFD_MTU; 123 } 124 125 /* helper to define static CAN controller features at device creation time */ 126 static inline void can_set_static_ctrlmode(struct net_device *dev, 127 u32 static_mode) 128 { 129 struct can_priv *priv = netdev_priv(dev); 130 131 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 132 priv->ctrlmode = static_mode; 133 priv->ctrlmode_static = static_mode; 134 135 /* override MTU which was set by default in can_setup()? */ 136 if (static_mode & CAN_CTRLMODE_FD) 137 dev->mtu = CANFD_MTU; 138 } 139 140 /* get data length from can_dlc with sanitized can_dlc */ 141 u8 can_dlc2len(u8 can_dlc); 142 143 /* map the sanitized data length to an appropriate data length code */ 144 u8 can_len2dlc(u8 len); 145 146 struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, 147 unsigned int txqs, unsigned int rxqs); 148 #define alloc_candev(sizeof_priv, echo_skb_max) \ 149 alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1) 150 #define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \ 151 alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count) 152 void free_candev(struct net_device *dev); 153 154 /* a candev safe wrapper around netdev_priv */ 155 struct can_priv *safe_candev_priv(struct net_device *dev); 156 157 int open_candev(struct net_device *dev); 158 void close_candev(struct net_device *dev); 159 int can_change_mtu(struct net_device *dev, int new_mtu); 160 161 int register_candev(struct net_device *dev); 162 void unregister_candev(struct net_device *dev); 163 164 int can_restart_now(struct net_device *dev); 165 void can_bus_off(struct net_device *dev); 166 167 void can_change_state(struct net_device *dev, struct can_frame *cf, 168 enum can_state tx_state, enum can_state rx_state); 169 170 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, 171 unsigned int idx); 172 struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, 173 u8 *len_ptr); 174 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx); 175 void can_free_echo_skb(struct net_device *dev, unsigned int idx); 176 177 #ifdef CONFIG_OF 178 void of_can_transceiver(struct net_device *dev); 179 #else 180 static inline void of_can_transceiver(struct net_device *dev) { } 181 #endif 182 183 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf); 184 struct sk_buff *alloc_canfd_skb(struct net_device *dev, 185 struct canfd_frame **cfd); 186 struct sk_buff *alloc_can_err_skb(struct net_device *dev, 187 struct can_frame **cf); 188 189 #endif /* !_CAN_DEV_H */ 190