1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* linux/can/dev.h
*
* Definitions for the CAN network device driver interface
*
* Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com>
* Varma Electronics Oy
*
* Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com>
*
*/
#ifndef _CAN_DEV_H
#define _CAN_DEV_H
#include <linux/can.h>
#include <linux/can/bittiming.h>
#include <linux/can/error.h>
#include <linux/can/led.h>
#include <linux/can/length.h>
#include <linux/can/netlink.h>
#include <linux/can/skb.h>
#include <linux/netdevice.h>
/*
* CAN mode
*/
enum can_mode {
CAN_MODE_STOP = 0,
CAN_MODE_START,
CAN_MODE_SLEEP
};
/*
* CAN common private data
*/
struct can_priv {
struct net_device *dev;
struct can_device_stats can_stats;
struct can_bittiming bittiming, data_bittiming;
const struct can_bittiming_const *bittiming_const,
*data_bittiming_const;
const u16 *termination_const;
unsigned int termination_const_cnt;
u16 termination;
const u32 *bitrate_const;
unsigned int bitrate_const_cnt;
const u32 *data_bitrate_const;
unsigned int data_bitrate_const_cnt;
u32 bitrate_max;
struct can_clock clock;
enum can_state state;
/* CAN controller features - see include/uapi/linux/can/netlink.h */
u32 ctrlmode; /* current options setting */
u32 ctrlmode_supported; /* options that can be modified by netlink */
u32 ctrlmode_static; /* static enabled options for driver/hardware */
int restart_ms;
struct delayed_work restart_work;
int (*do_set_bittiming)(struct net_device *dev);
int (*do_set_data_bittiming)(struct net_device *dev);
int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
int (*do_set_termination)(struct net_device *dev, u16 term);
int (*do_get_state)(const struct net_device *dev,
enum can_state *state);
int (*do_get_berr_counter)(const struct net_device *dev,
struct can_berr_counter *bec);
unsigned int echo_skb_max;
struct sk_buff **echo_skb;
#ifdef CONFIG_CAN_LEDS
struct led_trigger *tx_led_trig;
char tx_led_trig_name[CAN_LED_NAME_SZ];
struct led_trigger *rx_led_trig;
char rx_led_trig_name[CAN_LED_NAME_SZ];
struct led_trigger *rxtx_led_trig;
char rxtx_led_trig_name[CAN_LED_NAME_SZ];
#endif
};
/* Check for outgoing skbs that have not been created by the CAN subsystem */
static inline bool can_skb_headroom_valid(struct net_device *dev,
struct sk_buff *skb)
{
/* af_packet creates a headroom of HH_DATA_MOD bytes which is fine */
if (WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct can_skb_priv)))
return false;
/* af_packet does not apply CAN skb specific settings */
if (skb->ip_summed == CHECKSUM_NONE) {
/* init headroom */
can_skb_prv(skb)->ifindex = dev->ifindex;
can_skb_prv(skb)->skbcnt = 0;
skb->ip_summed = CHECKSUM_UNNECESSARY;
/* perform proper loopback on capable devices */
if (dev->flags & IFF_ECHO)
skb->pkt_type = PACKET_LOOPBACK;
else
skb->pkt_type = PACKET_HOST;
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
}
return true;
}
/* Drop a given socketbuffer if it does not contain a valid CAN frame. */
static inline bool can_dropped_invalid_skb(struct net_device *dev,
struct sk_buff *skb)
{
const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
if (skb->protocol == htons(ETH_P_CAN)) {
if (unlikely(skb->len != CAN_MTU ||
cfd->len > CAN_MAX_DLEN))
goto inval_skb;
} else if (skb->protocol == htons(ETH_P_CANFD)) {
if (unlikely(skb->len != CANFD_MTU ||
cfd->len > CANFD_MAX_DLEN))
goto inval_skb;
} else
goto inval_skb;
if (!can_skb_headroom_valid(dev, skb))
goto inval_skb;
return false;
inval_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return true;
}
static inline bool can_is_canfd_skb(const struct sk_buff *skb)
{
/* the CAN specific type of skb is identified by its data length */
return skb->len == CANFD_MTU;
}
/* helper to define static CAN controller features at device creation time */
static inline void can_set_static_ctrlmode(struct net_device *dev,
u32 static_mode)
{
struct can_priv *priv = netdev_priv(dev);
/* alloc_candev() succeeded => netdev_priv() is valid at this point */
priv->ctrlmode = static_mode;
priv->ctrlmode_static = static_mode;
/* override MTU which was set by default in can_setup()? */
if (static_mode & CAN_CTRLMODE_FD)
dev->mtu = CANFD_MTU;
}
struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
unsigned int txqs, unsigned int rxqs);
#define alloc_candev(sizeof_priv, echo_skb_max) \
alloc_candev_mqs(sizeof_priv, echo_skb_max, 1, 1)
#define alloc_candev_mq(sizeof_priv, echo_skb_max, count) \
alloc_candev_mqs(sizeof_priv, echo_skb_max, count, count)
void free_candev(struct net_device *dev);
/* a candev safe wrapper around netdev_priv */
struct can_priv *safe_candev_priv(struct net_device *dev);
int open_candev(struct net_device *dev);
void close_candev(struct net_device *dev);
int can_change_mtu(struct net_device *dev, int new_mtu);
int register_candev(struct net_device *dev);
void unregister_candev(struct net_device *dev);
int can_restart_now(struct net_device *dev);
void can_bus_off(struct net_device *dev);
void can_change_state(struct net_device *dev, struct can_frame *cf,
enum can_state tx_state, enum can_state rx_state);
int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
unsigned int idx);
struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
u8 *len_ptr);
unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
void can_free_echo_skb(struct net_device *dev, unsigned int idx);
#ifdef CONFIG_OF
void of_can_transceiver(struct net_device *dev);
#else
static inline void of_can_transceiver(struct net_device *dev) { }
#endif
struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
struct sk_buff *alloc_canfd_skb(struct net_device *dev,
struct canfd_frame **cfd);
struct sk_buff *alloc_can_err_skb(struct net_device *dev,
struct can_frame **cf);
#endif /* !_CAN_DEV_H */
|