drivers/staging/ccg/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 /* variant of gether_setup that allows customizing network device name */
  73 int gether_setup_name(struct usb_gadget *g, u8 ethaddr[ETH_ALEN],
  74                 const char *netname);
  75
  76 /* netdev setup/teardown as directed by the gadget driver */
  77 /* gether_setup - initialize one ethernet-over-usb link
  78  * @g: gadget to associated with these links
  79  * @ethaddr: NULL, or a buffer in which the ethernet address of the
  80  *      host side of the link is recorded
  81  * Context: may sleep
  82  *
  83  * This sets up the single network link that may be exported by a
  84  * gadget driver using this framework.  The link layer addresses are
  85  * set up using module parameters.
  86  *
  87  * Returns negative errno, or zero on success
  88  */
  89 static inline int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN])
  90 {
  91         return gether_setup_name(g, ethaddr, "usb");
  92 }
  93
  94 void gether_cleanup(void);
  95
  96 /* connect/disconnect is handled by individual functions */
  97 struct net_device *gether_connect(struct gether *);
  98 void gether_disconnect(struct gether *);
  99
 100 /* Some controllers can't support CDC Ethernet (ECM) ... */
 101 static inline bool can_support_ecm(struct usb_gadget *gadget)
 102 {
 103         if (!gadget_supports_altsettings(gadget))
 104                 return false;
 105
 106         /* Everything else is *presumably* fine ... but this is a bit
 107          * chancy, so be **CERTAIN** there are no hardware issues with
 108          * your controller.  Add it above if it can't handle CDC.
 109          */
 110         return true;
 111 }
 112
 113 /* each configuration may bind one instance of an ethernet link */
 114 int geth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 115 int ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 116 int ncm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 117 int eem_bind_config(struct usb_configuration *c);
 118
 119 #ifdef USB_ETH_RNDIS
 120
 121 int rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
 122                                 u32 vendorID, const char *manufacturer);
 123
 124 #else
 125
 126 static inline int
 127 rndis_bind_config_vendor(struct usb_configuration *c, u8 ethaddr[ETH_ALEN],
 128                                 u32 vendorID, const char *manufacturer)
 129 {
 130         return 0;
 131 }
 132
 133 #endif
 134
 135 /**
 136  * rndis_bind_config - add RNDIS network link to a configuration
 137  * @c: the configuration to support the network link
 138  * @ethaddr: a buffer in which the ethernet address of the host side
 139  *      side of the link was recorded
 140  * Context: single threaded during gadget setup
 141  *
 142  * Returns zero on success, else negative errno.
 143  *
 144  * Caller must have called @gether_setup().  Caller is also responsible
 145  * for calling @gether_cleanup() before module unload.
 146  */
 147 static inline int rndis_bind_config(struct usb_configuration *c,
 148                                     u8 ethaddr[ETH_ALEN])
 149 {
 150         return rndis_bind_config_vendor(c, ethaddr, 0, NULL);
 151 }
 152
 153
 154 #endif /* __U_ETHER_H */