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/bittiming.h> 19 #include <linux/can/error.h> 20 #include <linux/can/length.h> 21 #include <linux/can/netlink.h> 22 #include <linux/can/skb.h> 23 #include <linux/ethtool.h> 24 #include <linux/netdevice.h> 25 26 /* 27 * CAN mode 28 */ 29 enum can_mode { 30 CAN_MODE_STOP = 0, 31 CAN_MODE_START, 32 CAN_MODE_SLEEP 33 }; 34 35 enum can_termination_gpio { 36 CAN_TERMINATION_GPIO_DISABLED = 0, 37 CAN_TERMINATION_GPIO_ENABLED, 38 CAN_TERMINATION_GPIO_MAX, 39 }; 40 41 struct data_bittiming_params { 42 const struct can_bittiming_const *data_bittiming_const; 43 struct can_bittiming data_bittiming; 44 const struct can_tdc_const *tdc_const; 45 struct can_tdc tdc; 46 const u32 *data_bitrate_const; 47 unsigned int data_bitrate_const_cnt; 48 int (*do_set_data_bittiming)(struct net_device *dev); 49 int (*do_get_auto_tdcv)(const struct net_device *dev, u32 *tdcv); 50 }; 51 52 /* 53 * CAN common private data 54 */ 55 struct can_priv { 56 struct net_device *dev; 57 struct can_device_stats can_stats; 58 59 const struct can_bittiming_const *bittiming_const; 60 struct can_bittiming bittiming; 61 struct data_bittiming_params fd; 62 unsigned int bitrate_const_cnt; 63 const u32 *bitrate_const; 64 u32 bitrate_max; 65 struct can_clock clock; 66 67 unsigned int termination_const_cnt; 68 const u16 *termination_const; 69 u16 termination; 70 struct gpio_desc *termination_gpio; 71 u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX]; 72 73 unsigned int echo_skb_max; 74 struct sk_buff **echo_skb; 75 76 enum can_state state; 77 78 /* CAN controller features - see include/uapi/linux/can/netlink.h */ 79 u32 ctrlmode; /* current options setting */ 80 u32 ctrlmode_supported; /* options that can be modified by netlink */ 81 82 int restart_ms; 83 struct delayed_work restart_work; 84 85 int (*do_set_bittiming)(struct net_device *dev); 86 int (*do_set_mode)(struct net_device *dev, enum can_mode mode); 87 int (*do_set_termination)(struct net_device *dev, u16 term); 88 int (*do_get_state)(const struct net_device *dev, 89 enum can_state *state); 90 int (*do_get_berr_counter)(const struct net_device *dev, 91 struct can_berr_counter *bec); 92 }; 93 94 static inline bool can_tdc_is_enabled(const struct can_priv *priv) 95 { 96 return !!(priv->ctrlmode & CAN_CTRLMODE_TDC_MASK); 97 } 98 99 /* 100 * can_get_relative_tdco() - TDCO relative to the sample point 101 * 102 * struct can_tdc::tdco represents the absolute offset from TDCV. Some 103 * controllers use instead an offset relative to the Sample Point (SP) 104 * such that: 105 * 106 * SSP = TDCV + absolute TDCO 107 * = TDCV + SP + relative TDCO 108 * 109 * -+----------- one bit ----------+-- TX pin 110 * |<--- Sample Point --->| 111 * 112 * --+----------- one bit ----------+-- RX pin 113 * |<-------- TDCV -------->| 114 * |<------------------------>| absolute TDCO 115 * |<--- Sample Point --->| 116 * | |<->| relative TDCO 117 * |<------------- Secondary Sample Point ------------>| 118 */ 119 static inline s32 can_get_relative_tdco(const struct can_priv *priv) 120 { 121 const struct can_bittiming *dbt = &priv->fd.data_bittiming; 122 s32 sample_point_in_tc = (CAN_SYNC_SEG + dbt->prop_seg + 123 dbt->phase_seg1) * dbt->brp; 124 125 return (s32)priv->fd.tdc.tdco - sample_point_in_tc; 126 } 127 128 /* helper to define static CAN controller features at device creation time */ 129 static inline int __must_check can_set_static_ctrlmode(struct net_device *dev, 130 u32 static_mode) 131 { 132 struct can_priv *priv = netdev_priv(dev); 133 134 /* alloc_candev() succeeded => netdev_priv() is valid at this point */ 135 if (priv->ctrlmode_supported & static_mode) { 136 netdev_warn(dev, 137 "Controller features can not be supported and static at the same time\n"); 138 return -EINVAL; 139 } 140 priv->ctrlmode = static_mode; 141 142 /* override MTU which was set by default in can_setup()? */ 143 if (static_mode & CAN_CTRLMODE_FD) 144 dev->mtu = CANFD_MTU; 145 146 return 0; 147 } 148 149 static inline u32 can_get_static_ctrlmode(struct can_priv *priv) 150 { 151 return priv->ctrlmode & ~priv->ctrlmode_supported; 152 } 153 154 static inline bool can_is_canxl_dev_mtu(unsigned int mtu) 155 { 156 return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU); 157 } 158 159 /* drop skb if it does not contain a valid CAN frame for sending */ 160 static inline bool can_dev_dropped_skb(struct net_device *dev, struct sk_buff *skb) 161 { 162 struct can_priv *priv = netdev_priv(dev); 163 164 if (priv->ctrlmode & CAN_CTRLMODE_LISTENONLY) { 165 netdev_info_once(dev, 166 "interface in listen only mode, dropping skb\n"); 167 kfree_skb(skb); 168 dev->stats.tx_dropped++; 169 return true; 170 } 171 172 return can_dropped_invalid_skb(dev, skb); 173 } 174 175 void can_setup(struct net_device *dev); 176 177 struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, 178 unsigned int txqs, unsigned int rxqs); 179 #define alloc_candev(sizeof_priv, echo_skb_max) \ 180 alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1) 181 #define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \ 182 alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count) 183 void free_candev(struct net_device *dev); 184 185 /* a candev safe wrapper around netdev_priv */ 186 struct can_priv *safe_candev_priv(struct net_device *dev); 187 188 int open_candev(struct net_device *dev); 189 void close_candev(struct net_device *dev); 190 int can_change_mtu(struct net_device *dev, int new_mtu); 191 int can_eth_ioctl_hwts(struct net_device *netdev, struct ifreq *ifr, int cmd); 192 int can_ethtool_op_get_ts_info_hwts(struct net_device *dev, 193 struct kernel_ethtool_ts_info *info); 194 195 int register_candev(struct net_device *dev); 196 void unregister_candev(struct net_device *dev); 197 198 int can_restart_now(struct net_device *dev); 199 void can_bus_off(struct net_device *dev); 200 201 const char *can_get_state_str(const enum can_state state); 202 void can_state_get_by_berr_counter(const struct net_device *dev, 203 const struct can_berr_counter *bec, 204 enum can_state *tx_state, 205 enum can_state *rx_state); 206 void can_change_state(struct net_device *dev, struct can_frame *cf, 207 enum can_state tx_state, enum can_state rx_state); 208 209 #ifdef CONFIG_OF 210 void of_can_transceiver(struct net_device *dev); 211 #else 212 static inline void of_can_transceiver(struct net_device *dev) { } 213 #endif 214 215 extern struct rtnl_link_ops can_link_ops; 216 int can_netlink_register(void); 217 void can_netlink_unregister(void); 218 219 #endif /* !_CAN_DEV_H */ 220