1 /*
2 * linux/can/dev.h
3 *
4 * Definitions for the CAN network device driver interface
5 *
6 * Copyright (C) 2006 Andrey Volkov <avolkov@varma-el.com>
7 * Varma Electronics Oy
8 *
9 * Copyright (C) 2008 Wolfgang Grandegger <wg@grandegger.com>
10 *
11 */
12
13 #ifndef _CAN_DEV_H
14 #define _CAN_DEV_H
15
16 #include <linux/can.h>
17 #include <linux/can/error.h>
18 #include <linux/can/led.h>
19 #include <linux/can/netlink.h>
20 #include <linux/netdevice.h>
21
22 /*
23 * CAN mode
24 */
25 enum can_mode {
26 CAN_MODE_STOP = 0,
27 CAN_MODE_START,
28 CAN_MODE_SLEEP
29 };
30
31 /*
32 * CAN common private data
33 */
34 struct can_priv {
35 struct can_device_stats can_stats;
36
37 struct can_bittiming bittiming, data_bittiming;
38 const struct can_bittiming_const *bittiming_const,
39 *data_bittiming_const;
40 struct can_clock clock;
41
42 enum can_state state;
43 u32 ctrlmode;
44 u32 ctrlmode_supported;
45
46 int restart_ms;
47 struct timer_list restart_timer;
48
49 int (*do_set_bittiming)(struct net_device *dev);
50 int (*do_set_data_bittiming)(struct net_device *dev);
51 int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
52 int (*do_get_state)(const struct net_device *dev,
53 enum can_state *state);
54 int (*do_get_berr_counter)(const struct net_device *dev,
55 struct can_berr_counter *bec);
56
57 unsigned int echo_skb_max;
58 struct sk_buff **echo_skb;
59
60 #ifdef CONFIG_CAN_LEDS
61 struct led_trigger *tx_led_trig;
62 char tx_led_trig_name[CAN_LED_NAME_SZ];
63 struct led_trigger *rx_led_trig;
64 char rx_led_trig_name[CAN_LED_NAME_SZ];
65 struct led_trigger *rxtx_led_trig;
66 char rxtx_led_trig_name[CAN_LED_NAME_SZ];
67 #endif
68 };
69
70 /*
71 * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
72 * to __u8 and ensure the dlc value to be max. 8 bytes.
73 *
74 * To be used in the CAN netdriver receive path to ensure conformance with
75 * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
76 */
77 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC))
78 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC))
79
80 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */
can_dropped_invalid_skb(struct net_device * dev,struct sk_buff * skb)81 static inline bool can_dropped_invalid_skb(struct net_device *dev,
82 struct sk_buff *skb)
83 {
84 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
85
86 if (skb->protocol == htons(ETH_P_CAN)) {
87 if (unlikely(skb->len != CAN_MTU ||
88 cfd->len > CAN_MAX_DLEN))
89 goto inval_skb;
90 } else if (skb->protocol == htons(ETH_P_CANFD)) {
91 if (unlikely(skb->len != CANFD_MTU ||
92 cfd->len > CANFD_MAX_DLEN))
93 goto inval_skb;
94 } else
95 goto inval_skb;
96
97 return false;
98
99 inval_skb:
100 kfree_skb(skb);
101 dev->stats.tx_dropped++;
102 return true;
103 }
104
can_is_canfd_skb(const struct sk_buff * skb)105 static inline bool can_is_canfd_skb(const struct sk_buff *skb)
106 {
107 /* the CAN specific type of skb is identified by its data length */
108 return skb->len == CANFD_MTU;
109 }
110
111 /* get data length from can_dlc with sanitized can_dlc */
112 u8 can_dlc2len(u8 can_dlc);
113
114 /* map the sanitized data length to an appropriate data length code */
115 u8 can_len2dlc(u8 len);
116
117 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
118 void free_candev(struct net_device *dev);
119
120 /* a candev safe wrapper around netdev_priv */
121 struct can_priv *safe_candev_priv(struct net_device *dev);
122
123 int open_candev(struct net_device *dev);
124 void close_candev(struct net_device *dev);
125 int can_change_mtu(struct net_device *dev, int new_mtu);
126
127 int register_candev(struct net_device *dev);
128 void unregister_candev(struct net_device *dev);
129
130 int can_restart_now(struct net_device *dev);
131 void can_bus_off(struct net_device *dev);
132
133 void can_change_state(struct net_device *dev, struct can_frame *cf,
134 enum can_state tx_state, enum can_state rx_state);
135
136 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
137 unsigned int idx);
138 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
139 void can_free_echo_skb(struct net_device *dev, unsigned int idx);
140
141 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
142 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
143 struct canfd_frame **cfd);
144 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
145 struct can_frame **cf);
146
147 #endif /* !_CAN_DEV_H */
148