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