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  */
  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
  20 /*
  21  * CAN mode
  22  */
  23 enum can_mode {
  24         CAN_MODE_STOP = 0,
  25         CAN_MODE_START,
  26         CAN_MODE_SLEEP
  27 };
  28
  29 /*
  30  * CAN common private data
  31  */
  32 struct can_priv {
  33         struct can_device_stats can_stats;
  34
  35         struct can_bittiming bittiming;
  36         struct can_bittiming_const *bittiming_const;
  37         struct can_clock clock;
  38
  39         enum can_state state;
  40         u32 ctrlmode;
  41         u32 ctrlmode_supported;
  42
  43         int restart_ms;
  44         struct timer_list restart_timer;
  45
  46         int (*do_set_bittiming)(struct net_device *dev);
  47         int (*do_set_mode)(struct net_device *dev, enum can_mode mode);
  48         int (*do_get_state)(const struct net_device *dev,
  49                             enum can_state *state);
  50         int (*do_get_berr_counter)(const struct net_device *dev,
  51                                    struct can_berr_counter *bec);
  52
  53         unsigned int echo_skb_max;
  54         struct sk_buff **echo_skb;
  55 };
  56
  57 /*
  58  * get_can_dlc(value) - helper macro to cast a given data length code (dlc)
  59  * to __u8 and ensure the dlc value to be max. 8 bytes.
  60  *
  61  * To be used in the CAN netdriver receive path to ensure conformance with
  62  * ISO 11898-1 Chapter 8.4.2.3 (DLC field)
  63  */
  64 #define get_can_dlc(i)  (min_t(__u8, (i), 8))
  65
  66 /* Drop a given socketbuffer if it does not contain a valid CAN frame. */
  67 static inline int can_dropped_invalid_skb(struct net_device *dev,
  68                                           struct sk_buff *skb)
  69 {
  70         const struct can_frame *cf = (struct can_frame *)skb->data;
  71
  72         if (unlikely(skb->len != sizeof(*cf) || cf->can_dlc > 8)) {
  73                 kfree_skb(skb);
  74                 dev->stats.tx_dropped++;
  75                 return 1;
  76         }
  77
  78         return 0;
  79 }
  80
  81 struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
  82 void free_candev(struct net_device *dev);
  83
  84 int open_candev(struct net_device *dev);
  85 void close_candev(struct net_device *dev);
  86
  87 int register_candev(struct net_device *dev);
  88 void unregister_candev(struct net_device *dev);
  89
  90 int can_restart_now(struct net_device *dev);
  91 void can_bus_off(struct net_device *dev);
  92
  93 void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
  94                       unsigned int idx);
  95 void can_get_echo_skb(struct net_device *dev, unsigned int idx);
  96 void can_free_echo_skb(struct net_device *dev, unsigned int idx);
  97
  98 struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
  99 struct sk_buff *alloc_can_err_skb(struct net_device *dev,
 100                                   struct can_frame **cf);
 101
 102 #endif /* CAN_DEV_H */