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