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/netlink.h>
18 #include <linux/can/error.h>
19 #include <linux/can/led.h>
20
21 /*
22 * CAN mode
23 */
24 enum can_mode {
25 CAN_MODE_STOP = 0,
26 CAN_MODE_START,
27 CAN_MODE_SLEEP
28 };
29
30 /*
31 * CAN common private data
32 */
33 struct can_priv {
34 struct can_device_stats can_stats;
35
36 struct can_bittiming bittiming, data_bittiming;
37 const struct can_bittiming_const *bittiming_const,
38 *data_bittiming_const;
39 struct can_clock clock;
40
41 enum can_state state;
42
43 /* CAN controller features - see include/uapi/linux/can/netlink.h */
44 u32 ctrlmode; /* current options setting */
45 u32 ctrlmode_supported; /* options that can be modified by netlink */
46 u32 ctrlmode_static; /* static enabled options for driver/hardware */
47
48 int restart_ms;
49 struct timer_list restart_timer;
50
51 int (*do_set_bittiming)(struct net_device *dev);
52 int (*do_set_data_bittiming)(struct net_device *dev);
53 int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
54 int (*do_get_state)(const struct net_device *dev,
55 enum can_state *state);
56 int (*do_get_berr_counter)(const struct net_device *dev,
57 struct can_berr_counter *bec);
58
59 unsigned int echo_skb_max;
60 struct sk_buff **echo_skb;
61
62 #ifdef CONFIG_CAN_LEDS
63 struct led_trigger *tx_led_trig;
64 char tx_led_trig_name[CAN_LED_NAME_SZ];
65 struct led_trigger *rx_led_trig;
66 char rx_led_trig_name[CAN_LED_NAME_SZ];
67 struct led_trigger *rxtx_led_trig;
68 char rxtx_led_trig_name[CAN_LED_NAME_SZ];
69 #endif
70 };
71
72 /*
73 * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
74 * to __u8 and ensure the dlc value to be max. 8 bytes.
75 *
76 * To be used in the CAN netdriver receive path to ensure conformance with
77 * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
78 */
79 #define get_can_dlc(i) (min_t(__u8, (i), CAN_MAX_DLC))
80 #define get_canfd_dlc(i) (min_t(__u8, (i), CANFD_MAX_DLC))
81
82 /* 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)83 static inline int can_dropped_invalid_skb(struct net_device *dev,
84 struct sk_buff *skb)
85 {
86 const struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
87
88 if (skb->protocol == htons(ETH_P_CAN)) {
89 if (unlikely(skb->len != CAN_MTU ||
90 cfd->len > CAN_MAX_DLEN))
91 goto inval_skb;
92 } else if (skb->protocol == htons(ETH_P_CANFD)) {
93 if (unlikely(skb->len != CANFD_MTU ||
94 cfd->len > CANFD_MAX_DLEN))
95 goto inval_skb;
96 } else
97 goto inval_skb;
98
99 return 0;
100
101 inval_skb:
102 kfree_skb(skb);
103 dev->stats.tx_dropped++;
104 return 1;
105 }
106
can_is_canfd_skb(const struct sk_buff * skb)107 static inline bool can_is_canfd_skb(const struct sk_buff *skb)
108 {
109 /* the CAN specific type of skb is identified by its data length */
110 return skb->len == CANFD_MTU;
111 }
112
113 /* helper to define static CAN controller features at device creation time */
can_set_static_ctrlmode(struct net_device * dev,u32 static_mode)114 static inline void can_set_static_ctrlmode(struct net_device *dev,
115 u32 static_mode)
116 {
117 struct can_priv *priv = netdev_priv(dev);
118
119 /* alloc_candev() succeeded => netdev_priv() is valid at this point */
120 priv->ctrlmode = static_mode;
121 priv->ctrlmode_static = static_mode;
122
123 /* override MTU which was set by default in can_setup()? */
124 if (static_mode & CAN_CTRLMODE_FD)
125 dev->mtu = CANFD_MTU;
126 }
127
128 /* get data length from can_dlc with sanitized can_dlc */
129 u8 can_dlc2len(u8 can_dlc);
130
131 /* map the sanitized data length to an appropriate data length code */
132 u8 can_len2dlc(u8 len);
133
134 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
135 void free_candev(struct net_device *dev);
136
137 /* a candev safe wrapper around netdev_priv */
138 struct can_priv *safe_candev_priv(struct net_device *dev);
139
140 int open_candev(struct net_device *dev);
141 void close_candev(struct net_device *dev);
142 int can_change_mtu(struct net_device *dev, int new_mtu);
143
144 int register_candev(struct net_device *dev);
145 void unregister_candev(struct net_device *dev);
146
147 int can_restart_now(struct net_device *dev);
148 void can_bus_off(struct net_device *dev);
149
150 void can_change_state(struct net_device *dev, struct can_frame *cf,
151 enum can_state tx_state, enum can_state rx_state);
152
153 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
154 unsigned int idx);
155 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
156 void can_free_echo_skb(struct net_device *dev, unsigned int idx);
157
158 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
159 struct sk_buff *alloc_canfd_skb(struct net_device *dev,
160 struct canfd_frame **cfd);
161 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
162 struct can_frame **cf);
163
164 #endif /* !_CAN_DEV_H */
165