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  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #ifndef __U_ETHER_H
  24 #define __U_ETHER_H
  25
  26 #include <linux/err.h>
  27 #include <linux/if_ether.h>
  28 #include <linux/usb/composite.h>
  29 #include <linux/usb/cdc.h>
  30
  31 #include "gadget_chips.h"
  32
  33
  34 /*
  35  * This represents the USB side of an "ethernet" link, managed by a USB
  36  * function which provides control and (maybe) framing.  Two functions
  37  * in different configurations could share the same ethernet link/netdev,
  38  * using different host interaction models.
  39  *
  40  * There is a current limitation that only one instance of this link may
  41  * be present in any given configuration.  When that's a problem, network
  42  * layer facilities can be used to package multiple logical links on this
  43  * single "physical" one.
  44  */
  45 struct gether {
  46         struct usb_function             func;
  47
  48         /* updated by gether_{connect,disconnect} */
  49         struct eth_dev                  *ioport;
  50
  51         /* endpoints handle full and/or high speeds */
  52         struct usb_ep                   *in_ep;
  53         struct usb_ep                   *out_ep;
  54
  55         /* descriptors match device speed at gether_connect() time */
  56         struct usb_endpoint_descriptor  *in;
  57         struct usb_endpoint_descriptor  *out;
  58
  59         bool                            is_zlp_ok;
  60
  61         u16                             cdc_filter;
  62
  63         /* hooks for added framing, as needed for RNDIS and EEM.
  64          * we currently don't support multiple frames per SKB.
  65          */
  66         u32                             header_len;
  67         struct sk_buff                  *(*wrap)(struct sk_buff *skb);
  68         int                             (*unwrap)(struct sk_buff *skb);
  69
  70         /* called on network open/close */
  71         void                            (*open)(struct gether *);
  72         void                            (*close)(struct gether *);
  73 };
  74
  75 #define DEFAULT_FILTER  (USB_CDC_PACKET_TYPE_BROADCAST \
  76                         |USB_CDC_PACKET_TYPE_ALL_MULTICAST \
  77                         |USB_CDC_PACKET_TYPE_PROMISCUOUS \
  78                         |USB_CDC_PACKET_TYPE_DIRECTED)
  79
  80
  81 /* netdev setup/teardown as directed by the gadget driver */
  82 int gether_setup(struct usb_gadget *g, u8 ethaddr[ETH_ALEN]);
  83 void gether_cleanup(void);
  84
  85 /* connect/disconnect is handled by individual functions */
  86 struct net_device *gether_connect(struct gether *);
  87 void gether_disconnect(struct gether *);
  88
  89 /* Some controllers can't support CDC Ethernet (ECM) ... */
  90 static inline bool can_support_ecm(struct usb_gadget *gadget)
  91 {
  92         if (!gadget_supports_altsettings(gadget))
  93                 return false;
  94
  95         /* SA1100 can do ECM, *without* status endpoint ... but we'll
  96          * only use it in non-ECM mode for backwards compatibility
  97          * (and since we currently require a status endpoint)
  98          */
  99         if (gadget_is_sa1100(gadget))
 100                 return false;
 101
 102         /* Everything else is *presumably* fine ... but this is a bit
 103          * chancy, so be **CERTAIN** there are no hardware issues with
 104          * your controller.  Add it above if it can't handle CDC.
 105          */
 106         return true;
 107 }
 108
 109 /* each configuration may bind one instance of an ethernet link */
 110 int geth_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 111 int ecm_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 112
 113 #ifdef CONFIG_USB_ETH_RNDIS
 114
 115 int rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN]);
 116
 117 #else
 118
 119 static inline int
 120 rndis_bind_config(struct usb_configuration *c, u8 ethaddr[ETH_ALEN])
 121 {
 122         return 0;
 123 }
 124
 125 #endif
 126
 127 #endif /* __U_ETHER_H */