xref: /linux/include/linux/can/dev.h (revision 9e995c573b63453a904f3157813dc8cde4a6aba4)
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 	struct can_bittiming bittiming;
50 	struct data_bittiming_params fd, xl;
51 	unsigned int bitrate_const_cnt;
52 	const u32 *bitrate_const;
53 	u32 bitrate_max;
54 	struct can_clock clock;
55 
56 	unsigned int termination_const_cnt;
57 	const u16 *termination_const;
58 	u16 termination;
59 	struct gpio_desc *termination_gpio;
60 	u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX];
61 
62 	unsigned int echo_skb_max;
63 	struct sk_buff **echo_skb;
64 
65 	enum can_state state;
66 
67 	/* CAN controller features - see include/uapi/linux/can/netlink.h */
68 	u32 ctrlmode;		/* current options setting */
69 	u32 ctrlmode_supported;	/* options that can be modified by netlink */
70 
71 	int restart_ms;
72 	struct delayed_work restart_work;
73 
74 	int (*do_set_bittiming)(struct net_device *dev);
75 	int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
76 	int (*do_set_termination)(struct net_device *dev, u16 term);
77 	int (*do_get_state)(const struct net_device *dev,
78 			    enum can_state *state);
79 	int (*do_get_berr_counter)(const struct net_device *dev,
80 				   struct can_berr_counter *bec);
81 };
82 
can_fd_tdc_is_enabled(const struct can_priv * priv)83 static inline bool can_fd_tdc_is_enabled(const struct can_priv *priv)
84 {
85 	return !!(priv->ctrlmode & CAN_CTRLMODE_FD_TDC_MASK);
86 }
87 
can_xl_tdc_is_enabled(const struct can_priv * priv)88 static inline bool can_xl_tdc_is_enabled(const struct can_priv *priv)
89 {
90 	return !!(priv->ctrlmode & CAN_CTRLMODE_XL_TDC_MASK);
91 }
92 
can_get_static_ctrlmode(struct can_priv * priv)93 static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
94 {
95 	return priv->ctrlmode & ~priv->ctrlmode_supported;
96 }
97 
can_is_canxl_dev_mtu(unsigned int mtu)98 static inline bool can_is_canxl_dev_mtu(unsigned int mtu)
99 {
100 	return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU);
101 }
102 
103 void can_setup(struct net_device *dev);
104 
105 struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
106 				    unsigned int txqs, unsigned int rxqs);
107 #define alloc_candev(sizeof_priv, echo_skb_max) \
108 	alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1)
109 #define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \
110 	alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count)
111 void free_candev(struct net_device *dev);
112 
113 /* a candev safe wrapper around netdev_priv */
114 struct can_priv *safe_candev_priv(struct net_device *dev);
115 
116 int open_candev(struct net_device *dev);
117 void close_candev(struct net_device *dev);
118 void can_set_default_mtu(struct net_device *dev);
119 void can_set_cap_info(struct net_device *dev);
120 int __must_check can_set_static_ctrlmode(struct net_device *dev,
121 					 u32 static_mode);
122 int can_hwtstamp_get(struct net_device *netdev,
123 		     struct kernel_hwtstamp_config *cfg);
124 int can_hwtstamp_set(struct net_device *netdev,
125 		     struct kernel_hwtstamp_config *cfg,
126 		     struct netlink_ext_ack *extack);
127 int can_ethtool_op_get_ts_info_hwts(struct net_device *dev,
128 				    struct kernel_ethtool_ts_info *info);
129 
130 int register_candev(struct net_device *dev);
131 void unregister_candev(struct net_device *dev);
132 
133 int can_restart_now(struct net_device *dev);
134 void can_bus_off(struct net_device *dev);
135 
136 const char *can_get_state_str(const enum can_state state);
137 const char *can_get_ctrlmode_str(u32 ctrlmode);
138 
can_dev_in_xl_only_mode(struct can_priv * priv)139 static inline bool can_dev_in_xl_only_mode(struct can_priv *priv)
140 {
141 	const u32 mixed_mode = CAN_CTRLMODE_FD | CAN_CTRLMODE_XL;
142 
143 	/* When CAN XL is enabled but FD is disabled we are running in
144 	 * the so-called 'CANXL-only mode' where the error signalling is
145 	 * disabled. This helper function determines the required value
146 	 * to disable error signalling in the CAN XL controller.
147 	 * The so-called CC/FD/XL 'mixed mode' requires error signalling.
148 	 */
149 	return ((priv->ctrlmode & mixed_mode) == CAN_CTRLMODE_XL);
150 }
151 
152 /* 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)153 static inline bool can_dev_dropped_skb(struct net_device *dev, struct sk_buff *skb)
154 {
155 	struct can_priv *priv = netdev_priv(dev);
156 	u32 silent_mode = priv->ctrlmode & (CAN_CTRLMODE_LISTENONLY |
157 					    CAN_CTRLMODE_RESTRICTED);
158 
159 	if (silent_mode) {
160 		netdev_info_once(dev, "interface in %s mode, dropping skb\n",
161 				 can_get_ctrlmode_str(silent_mode));
162 		goto invalid_skb;
163 	}
164 
165 	if (!(priv->ctrlmode & CAN_CTRLMODE_FD) && can_is_canfd_skb(skb)) {
166 		netdev_info_once(dev, "CAN FD is disabled, dropping skb\n");
167 		goto invalid_skb;
168 	}
169 
170 	if (can_dev_in_xl_only_mode(priv) && !can_is_canxl_skb(skb)) {
171 		netdev_info_once(dev,
172 				 "Error signaling is disabled, dropping skb\n");
173 		goto invalid_skb;
174 	}
175 
176 	return can_dropped_invalid_skb(dev, skb);
177 
178 invalid_skb:
179 	kfree_skb(skb);
180 	dev->stats.tx_dropped++;
181 	return true;
182 }
183 
184 void can_state_get_by_berr_counter(const struct net_device *dev,
185 				   const struct can_berr_counter *bec,
186 				   enum can_state *tx_state,
187 				   enum can_state *rx_state);
188 void can_change_state(struct net_device *dev, struct can_frame *cf,
189 		      enum can_state tx_state, enum can_state rx_state);
190 
191 #ifdef CONFIG_OF
192 void of_can_transceiver(struct net_device *dev);
193 #else
of_can_transceiver(struct net_device * dev)194 static inline void of_can_transceiver(struct net_device *dev) { }
195 #endif
196 
197 extern struct rtnl_link_ops can_link_ops;
198 int can_netlink_register(void);
199 void can_netlink_unregister(void);
200 
201 #endif /* !_CAN_DEV_H */
202