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/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 */
  25enum can_mode {
  26        CAN_MODE_STOP = 0,
  27        CAN_MODE_START,
  28        CAN_MODE_SLEEP
  29};
  30
  31/*
  32 * CAN common private data
  33 */
  34struct 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. */
  81static 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
  99inval_skb:
 100        kfree_skb(skb);
 101        dev->stats.tx_dropped++;
 102        return true;
 103}
 104
 105static 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 */
 112u8 can_dlc2len(u8 can_dlc);
 113
 114/* map the sanitized data length to an appropriate data length code */
 115u8 can_len2dlc(u8 len);
 116
 117struct net_device *alloc_candev(int sizeof_priv, unsigned int echo_skb_max);
 118void free_candev(struct net_device *dev);
 119
 120/* a candev safe wrapper around netdev_priv */
 121struct can_priv *safe_candev_priv(struct net_device *dev);
 122
 123int open_candev(struct net_device *dev);
 124void close_candev(struct net_device *dev);
 125int can_change_mtu(struct net_device *dev, int new_mtu);
 126
 127int register_candev(struct net_device *dev);
 128void unregister_candev(struct net_device *dev);
 129
 130int can_restart_now(struct net_device *dev);
 131void can_bus_off(struct net_device *dev);
 132
 133void can_change_state(struct net_device *dev, struct can_frame *cf,
 134                      enum can_state tx_state, enum can_state rx_state);
 135
 136void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 137                      unsigned int idx);
 138unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
 139void can_free_echo_skb(struct net_device *dev, unsigned int idx);
 140
 141struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf);
 142struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 143                                struct canfd_frame **cfd);
 144struct sk_buff *alloc_can_err_skb(struct net_device *dev,
 145                                  struct can_frame **cf);
 146
 147#endif /* !_CAN_DEV_H */
 148