include/linux/can/dev.h

   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  * Send feedback to <socketcan-users@lists.berlios.de>
  12  */
  13
  14 #ifndef CAN_DEV_H
  15 #define CAN_DEV_H
  16
  17 #include <linux/can.h>
  18 #include <linux/can/netlink.h>
  19 #include <linux/can/error.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;
  37         struct can_bittiming_const *bittiming_const;
  38         struct can_clock clock;
  39
  40         enum can_state state;
  41         u32 ctrlmode;
  42         u32 ctrlmode_supported;
  43
  44         int restart_ms;
  45         struct timer_list restart_timer;
  46
  47         int (*do_set_bittiming)(struct net_device *dev);
  48         int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
  49         int (*do_get_state)(const struct net_device *dev,
  50                             enum can_state *state);
  51         int (*do_get_berr_counter)(const struct net_device *dev,
  52                                    struct can_berr_counter *bec);
  53
  54         unsigned int echo_skb_max;
  55         struct sk_buff **echo_skb;
  56 };
  57
  58 /*
  59  * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
  60  * to __u8 and ensure the dlc value to be max. 8 bytes.
  61  *
  62  * To be used in the CAN netdriver receive path to ensure conformance with
  63  * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
  64  */
  65 #define get_can_dlc(i)  (min_t(__u8, (i), 8))
  66
  67 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */
  68 static inline int can_dropped_invalid_skb(struct net_device *dev,
  69                                           struct sk_buff *skb)
  70 {
  71         const struct can_frame *cf = (struct can_frame *)skb->data;
  72
  73         if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) {
  74                 kfree_skb(skb);
  75                 dev->stats.tx_dropped++;
  76                 return 1;
  77         }
  78
  79         return 0;
  80 }
  81
  82 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
  83 void free_candev(struct net_device *dev);
  84
  85 int open_candev(struct net_device *dev);
  86 void close_candev(struct net_device *dev);
  87
  88 int register_candev(struct net_device *dev);
  89 void unregister_candev(struct net_device *dev);
  90
  91 int can_restart_now(struct net_device *dev);
  92 void can_bus_off(struct net_device *dev);
  93
  94 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
  95                       unsigned int idx);
  96 void can_get_echo_skb(struct net_device *dev, unsigned int idx);
  97 void can_free_echo_skb(struct net_device *dev, unsigned int idx);
  98
  99 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
 100 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
 101                                   struct can_frame **cf);
 102
 103 #endif /* CAN_DEV_H */