| 1 | /* |
| 2 | * Generic HDLC support routines for Linux |
| 3 | * |
| 4 | * Copyright (C) 1999-2005 Krzysztof Halasa <khc@pm.waw.pl> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify it |
| 7 | * under the terms of version 2 of the GNU General Public License |
| 8 | * as published by the Free Software Foundation. |
| 9 | */ |
| 10 | #ifndef __HDLC_H |
| 11 | #define __HDLC_H |
| 12 | |
| 13 | |
| 14 | #include <linux/skbuff.h> |
| 15 | #include <linux/netdevice.h> |
| 16 | #include <linux/hdlc/ioctl.h> |
| 17 | #include <uapi/linux/hdlc.h> |
| 18 | |
| 19 | /* This structure is a private property of HDLC protocols. |
| 20 | Hardware drivers have no interest here */ |
| 21 | |
| 22 | struct hdlc_proto { |
| 23 | int (*open)(struct net_device *dev); |
| 24 | void (*close)(struct net_device *dev); |
| 25 | void (*start)(struct net_device *dev); /* if open & DCD */ |
| 26 | void (*stop)(struct net_device *dev); /* if open & !DCD */ |
| 27 | void (*detach)(struct net_device *dev); |
| 28 | int (*ioctl)(struct net_device *dev, struct ifreq *ifr); |
| 29 | __be16 (*type_trans)(struct sk_buff *skb, struct net_device *dev); |
| 30 | int (*netif_rx)(struct sk_buff *skb); |
| 31 | netdev_tx_t (*xmit)(struct sk_buff *skb, struct net_device *dev); |
| 32 | struct module *module; |
| 33 | struct hdlc_proto *next; /* next protocol in the list */ |
| 34 | }; |
| 35 | |
| 36 | |
| 37 | /* Pointed to by netdev_priv(dev) */ |
| 38 | typedef struct hdlc_device { |
| 39 | /* used by HDLC layer to take control over HDLC device from hw driver*/ |
| 40 | int (*attach)(struct net_device *dev, |
| 41 | unsigned short encoding, unsigned short parity); |
| 42 | |
| 43 | /* hardware driver must handle this instead of dev->hard_start_xmit */ |
| 44 | netdev_tx_t (*xmit)(struct sk_buff *skb, struct net_device *dev); |
| 45 | |
| 46 | /* Things below are for HDLC layer internal use only */ |
| 47 | const struct hdlc_proto *proto; |
| 48 | int carrier; |
| 49 | int open; |
| 50 | spinlock_t state_lock; |
| 51 | void *state; |
| 52 | void *priv; |
| 53 | } hdlc_device; |
| 54 | |
| 55 | |
| 56 | |
| 57 | /* Exported from hdlc module */ |
| 58 | |
| 59 | /* Called by hardware driver when a user requests HDLC service */ |
| 60 | int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd); |
| 61 | |
| 62 | /* Must be used by hardware driver on module startup/exit */ |
| 63 | #define register_hdlc_device(dev) register_netdev(dev) |
| 64 | void unregister_hdlc_device(struct net_device *dev); |
| 65 | |
| 66 | |
| 67 | void register_hdlc_protocol(struct hdlc_proto *proto); |
| 68 | void unregister_hdlc_protocol(struct hdlc_proto *proto); |
| 69 | |
| 70 | struct net_device *alloc_hdlcdev(void *priv); |
| 71 | |
| 72 | static inline struct hdlc_device* dev_to_hdlc(struct net_device *dev) |
| 73 | { |
| 74 | return netdev_priv(dev); |
| 75 | } |
| 76 | |
| 77 | static __inline__ void debug_frame(const struct sk_buff *skb) |
| 78 | { |
| 79 | int i; |
| 80 | |
| 81 | for (i=0; i < skb->len; i++) { |
| 82 | if (i == 100) { |
| 83 | printk("...\n"); |
| 84 | return; |
| 85 | } |
| 86 | printk(" %02X", skb->data[i]); |
| 87 | } |
| 88 | printk("\n"); |
| 89 | } |
| 90 | |
| 91 | |
| 92 | /* Must be called by hardware driver when HDLC device is being opened */ |
| 93 | int hdlc_open(struct net_device *dev); |
| 94 | /* Must be called by hardware driver when HDLC device is being closed */ |
| 95 | void hdlc_close(struct net_device *dev); |
| 96 | /* May be used by hardware driver */ |
| 97 | int hdlc_change_mtu(struct net_device *dev, int new_mtu); |
| 98 | /* Must be pointed to by hw driver's dev->netdev_ops->ndo_start_xmit */ |
| 99 | netdev_tx_t hdlc_start_xmit(struct sk_buff *skb, struct net_device *dev); |
| 100 | |
| 101 | int attach_hdlc_protocol(struct net_device *dev, struct hdlc_proto *proto, |
| 102 | size_t size); |
| 103 | /* May be used by hardware driver to gain control over HDLC device */ |
| 104 | void detach_hdlc_protocol(struct net_device *dev); |
| 105 | |
| 106 | static __inline__ __be16 hdlc_type_trans(struct sk_buff *skb, |
| 107 | struct net_device *dev) |
| 108 | { |
| 109 | hdlc_device *hdlc = dev_to_hdlc(dev); |
| 110 | |
| 111 | skb->dev = dev; |
| 112 | skb_reset_mac_header(skb); |
| 113 | |
| 114 | if (hdlc->proto->type_trans) |
| 115 | return hdlc->proto->type_trans(skb, dev); |
| 116 | else |
| 117 | return htons(ETH_P_HDLC); |
| 118 | } |
| 119 | |
| 120 | #endif /* __HDLC_H */ |