Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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 */
26enum can_mode {
27 CAN_MODE_STOP = 0,
28 CAN_MODE_START,
29 CAN_MODE_SLEEP
30};
31
32/*
33 * CAN common private data
34 */
35struct 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 struct can_clock clock;
50
51 enum can_state state;
52
53 /* CAN controller features - see include/uapi/linux/can/netlink.h */
54 u32 ctrlmode; /* current options setting */
55 u32 ctrlmode_supported; /* options that can be modified by netlink */
56 u32 ctrlmode_static; /* static enabled options for driver/hardware */
57
58 int restart_ms;
59 struct delayed_work restart_work;
60
61 int (*do_set_bittiming)(struct net_device *dev);
62 int (*do_set_data_bittiming)(struct net_device *dev);
63 int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
64 int (*do_set_termination)(struct net_device *dev, u16 term);
65 int (*do_get_state)(const struct net_device *dev,
66 enum can_state *state);
67 int (*do_get_berr_counter)(const struct net_device *dev,
68 struct can_berr_counter *bec);
69
70 unsigned int echo_skb_max;
71 struct sk_buff **echo_skb;
72
73#ifdef CONFIG_CAN_LEDS
74 struct led_trigger *tx_led_trig;
75 char tx_led_trig_name[CAN_LED_NAME_SZ];
76 struct led_trigger *rx_led_trig;
77 char rx_led_trig_name[CAN_LED_NAME_SZ];
78 struct led_trigger *rxtx_led_trig;
79 char rxtx_led_trig_name[CAN_LED_NAME_SZ];
80#endif
81};
82
83/*
84 * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
85 * to __u8 and ensure the dlc value to be max. 8 bytes.
86 *
87 * To be used in the CAN netdriver receive path to ensure conformance with
88 * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
89 */
90#define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC))
91#define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC))
92
93/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
94static inline bool can_dropped_invalid_skb(struct net_device *dev,
95 struct sk_buff *skb)
96{
97 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
98
99 if (skb->protocol == htons(ETH_P_CAN)) {
100 if (unlikely(skb->len != CAN_MTU ||
101 cfd->len > CAN_MAX_DLEN))
102 goto inval_skb;
103 } else if (skb->protocol == htons(ETH_P_CANFD)) {
104 if (unlikely(skb->len != CANFD_MTU ||
105 cfd->len > CANFD_MAX_DLEN))
106 goto inval_skb;
107 } else
108 goto inval_skb;
109
110 return false;
111
112inval_skb:
113 kfree_skb(skb);
114 dev->stats.tx_dropped++;
115 return true;
116}
117
118static inline bool can_is_canfd_skb(const struct sk_buff *skb)
119{
120 /* the CAN specific type of skb is identified by its data length */
121 return skb->len == CANFD_MTU;
122}
123
124/* helper to define static CAN controller features at device creation time */
125static inline void 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 priv->ctrlmode = static_mode;
132 priv->ctrlmode_static = static_mode;
133
134 /* override MTU which was set by default in can_setup()? */
135 if (static_mode & CAN_CTRLMODE_FD)
136 dev->mtu = CANFD_MTU;
137}
138
139/* get data length from can_dlc with sanitized can_dlc */
140u8 can_dlc2len(u8 can_dlc);
141
142/* map the sanitized data length to an appropriate data length code */
143u8 can_len2dlc(u8 len);
144
145struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
146void free_candev(struct net_device *dev);
147
148/* a candev safe wrapper around netdev_priv */
149struct can_priv *safe_candev_priv(struct net_device *dev);
150
151int open_candev(struct net_device *dev);
152void close_candev(struct net_device *dev);
153int can_change_mtu(struct net_device *dev, int new_mtu);
154
155int register_candev(struct net_device *dev);
156void unregister_candev(struct net_device *dev);
157
158int can_restart_now(struct net_device *dev);
159void can_bus_off(struct net_device *dev);
160
161void can_change_state(struct net_device *dev, struct can_frame *cf,
162 enum can_state tx_state, enum can_state rx_state);
163
164void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
165 unsigned int idx);
166unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
167void can_free_echo_skb(struct net_device *dev, unsigned int idx);
168
169struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
170struct sk_buff *alloc_canfd_skb(struct net_device *dev,
171 struct canfd_frame **cfd);
172struct sk_buff *alloc_can_err_skb(struct net_device *dev,
173 struct can_frame **cf);
174
175#endif /* !_CAN_DEV_H */