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 */
29enum can_mode {
30 CAN_MODE_STOP = 0,
31 CAN_MODE_START,
32 CAN_MODE_SLEEP
33};
34
35enum 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 */
44struct 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
83static inline bool can_fd_tdc_is_enabled(const struct can_priv *priv)
84{
85 return !!(priv->ctrlmode & CAN_CTRLMODE_FD_TDC_MASK);
86}
87
88static inline bool can_xl_tdc_is_enabled(const struct can_priv *priv)
89{
90 return !!(priv->ctrlmode & CAN_CTRLMODE_XL_TDC_MASK);
91}
92
93static inline u32 can_get_static_ctrlmode(struct can_priv *priv)
94{
95 return priv->ctrlmode & ~priv->ctrlmode_supported;
96}
97
98static inline bool can_is_canxl_dev_mtu(unsigned int mtu)
99{
100 return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU);
101}
102
103void can_setup(struct net_device *dev);
104
105struct 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)
111void free_candev(struct net_device *dev);
112
113/* a candev safe wrapper around netdev_priv */
114struct can_priv *safe_candev_priv(struct net_device *dev);
115
116int open_candev(struct net_device *dev);
117void close_candev(struct net_device *dev);
118void can_set_default_mtu(struct net_device *dev);
119void can_set_cap_info(struct net_device *dev);
120int __must_check can_set_static_ctrlmode(struct net_device *dev,
121 u32 static_mode);
122int can_hwtstamp_get(struct net_device *netdev,
123 struct kernel_hwtstamp_config *cfg);
124int can_hwtstamp_set(struct net_device *netdev,
125 struct kernel_hwtstamp_config *cfg,
126 struct netlink_ext_ack *extack);
127int can_ethtool_op_get_ts_info_hwts(struct net_device *dev,
128 struct kernel_ethtool_ts_info *info);
129
130int register_candev(struct net_device *dev);
131void unregister_candev(struct net_device *dev);
132
133int can_restart_now(struct net_device *dev);
134void can_bus_off(struct net_device *dev);
135
136const char *can_get_state_str(const enum can_state state);
137const char *can_get_ctrlmode_str(u32 ctrlmode);
138
139static 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 */
153static 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
178invalid_skb:
179 kfree_skb(skb);
180 dev->stats.tx_dropped++;
181 return true;
182}
183
184void 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);
188void 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
192void of_can_transceiver(struct net_device *dev);
193#else
194static inline void of_can_transceiver(struct net_device *dev) { }
195#endif
196
197extern struct rtnl_link_ops can_link_ops;
198int can_netlink_register(void);
199void can_netlink_unregister(void);
200
201#endif /* !_CAN_DEV_H */
202

source code of linux/include/linux/can/dev.h