drivers/usb/gadget/u_ether.h

   1 /*
   2  * u_ether.h -- interface to USB gadget "ethernet link" utilities
   3  *
   4  * Copyright (C) 2003-2005,2008 David Brownell
   5  * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
   6  * Copyright (C) 2008 Nokia Corporation
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #ifndef __U_ETHER_H
  15 #define __U_ETHER_H
  16
  17 #include <linux/err.h>
  18 #include <linux/if_ether.h>
  19 #include <linux/usb/composite.h>
  20 #include <linux/usb/cdc.h>
  21
  22 #include "gadget_chips.h"
  23
  24
  25 /*
  26  * This represents the USB side of an "ethernet" link, managed by a USB
  27  * function which provides control and (maybe) framing.  Two functions
  28  * in different configurations could share the same ethernet link/netdev,
  29  * using different host interaction models.
  30  *
  31  * There is a current limitation that only one instance of this link may
  32  * be present in any given configuration.  When that's a problem, network
  33  * layer facilities can be used to package multiple logical links on this
  34  * single "physical" one.
  35  */
  36 struct gether {
  37         struct usb_function             func;
  38
  39         /* updated by gether_{connect,disconnect} */
  40         struct eth_dev                  *ioport;
  41
  42         /* endpoints handle full and/or high speeds */
  43         struct usb_ep                   *in_ep;
  44         struct usb_ep                   *out_ep;
  45
  46         bool                            is_zlp_ok;
  47
  48         u16                             cdc_filter;
  49
  50         /* hooks for added framing, as needed for RNDIS and EEM. */
  51         u32                             header_len;
  52         /* NCM requires fixed size bundles */
  53         bool                            is_fixed;
  54         u32                             fixed_out_len;
  55         u32                             fixed_in_len;
  56         struct sk_buff                  *(*wrap)(struct gether *port,
  57                                                 struct sk_buff *skb);
  58         int                             (*unwrap)(struct gether *port,
  59                                                 struct sk_buff *skb,
  60                                                 struct sk_buff_head *list);
  61
  62         /* called on network open/close */
  63         void                            (*open)(struct gether *);
  64         void                            (*close)(struct gether *);
  65 };
  66
  67 #define DEFAULT_FILTER  (USB_CDC_PACKET_TYPE_BROADCAST \
  68                         |USB_CDC_PACKET_TYPE_ALL_MULTICAST \
  69                         |USB_CDC_PACKET_TYPE_PROMISCUOUS \
  70                         |USB_CDC_PACKET_TYPE_DIRECTED)
  71
  72
  73 /* netdev setup/teardown as directed by the gadget driver */
  74 int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]);
  75 void gether_cleanup(void);
  76
  77 /* connect/disconnect is handled by individual functions */
  78 struct net_device *gether_connect(struct gether *);
  79 void gether_disconnect(struct gether *);
  80
  81 /* Some controllers can't support CDC Ethernet (ECM) ... */
  82 static inline bool can_support_ecm(struct usb_gadget *gadget)
  83 {
  84         if (!gadget_supports_altsettings(gadget))
  85                 return false;
  86
  87         /* Everything else is *presumably* fine ... but this is a bit
  88          * chancy, so be **CERTAIN** there are no hardware issues with
  89          * your controller.  Add it above if it can't handle CDC.
  90          */
  91         return true;
  92 }
  93
  94 /* each configuration may bind one instance of an ethernet link */
  95 int geth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
  96 int ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
  97 int ncm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
  98 int eem_bind_config(struct usb_configuration *c);
  99
 100 #ifdef USB_ETH_RNDIS
 101
 102 int rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 103
 104 #else
 105
 106 static inline int
 107 rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
 108 {
 109         return 0;
 110 }
 111
 112 #endif
 113
 114 #endif /* __U_ETHER_H */