drivers/usb/gadget/function/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 #include <linux/netdevice.h>
  22
  23 #include "gadget_chips.h"
  24
  25 #define QMULT_DEFAULT 5
  26
  27 /*
  28  * dev_addr: initial value
  29  * changed by "ifconfig usb0 hw ether xx:xx:xx:xx:xx:xx"
  30  * host_addr: this address is invisible to ifconfig
  31  */
  32 #define USB_ETHERNET_MODULE_PARAMETERS() \
  33         static unsigned qmult = QMULT_DEFAULT;                          \
  34         module_param(qmult, uint, S_IRUGO|S_IWUSR);                     \
  35         MODULE_PARM_DESC(qmult, "queue length multiplier at high/super speed");\
  36                                                                         \
  37         static char *dev_addr;                                          \
  38         module_param(dev_addr, charp, S_IRUGO);                         \
  39         MODULE_PARM_DESC(dev_addr, "Device Ethernet Address");          \
  40                                                                         \
  41         static char *host_addr;                                         \
  42         module_param(host_addr, charp, S_IRUGO);                        \
  43         MODULE_PARM_DESC(host_addr, "Host Ethernet Address")
  44
  45 struct eth_dev;
  46
  47 /*
  48  * This represents the USB side of an "ethernet" link, managed by a USB
  49  * function which provides control and (maybe) framing.  Two functions
  50  * in different configurations could share the same ethernet link/netdev,
  51  * using different host interaction models.
  52  *
  53  * There is a current limitation that only one instance of this link may
  54  * be present in any given configuration.  When that's a problem, network
  55  * layer facilities can be used to package multiple logical links on this
  56  * single "physical" one.
  57  */
  58 struct gether {
  59         struct usb_function             func;
  60
  61         /* updated by gether_{connect,disconnect} */
  62         struct eth_dev                  *ioport;
  63
  64         /* endpoints handle full and/or high speeds */
  65         struct usb_ep                   *in_ep;
  66         struct usb_ep                   *out_ep;
  67
  68         bool                            is_zlp_ok;
  69
  70         u16                             cdc_filter;
  71
  72         /* hooks for added framing, as needed for RNDIS and EEM. */
  73         u32                             header_len;
  74         /* NCM requires fixed size bundles */
  75         bool                            is_fixed;
  76         u32                             fixed_out_len;
  77         u32                             fixed_in_len;
  78         bool                            supports_multi_frame;
  79         struct sk_buff                  *(*wrap)(struct gether *port,
  80                                                 struct sk_buff *skb);
  81         int                             (*unwrap)(struct gether *port,
  82                                                 struct sk_buff *skb,
  83                                                 struct sk_buff_head *list);
  84
  85         /* called on network open/close */
  86         void                            (*open)(struct gether *);
  87         void                            (*close)(struct gether *);
  88 };
  89
  90 #define DEFAULT_FILTER  (USB_CDC_PACKET_TYPE_BROADCAST \
  91                         |USB_CDC_PACKET_TYPE_ALL_MULTICAST \
  92                         |USB_CDC_PACKET_TYPE_PROMISCUOUS \
  93                         |USB_CDC_PACKET_TYPE_DIRECTED)
  94
  95 /* variant of gether_setup that allows customizing network device name */
  96 struct eth_dev *gether_setup_name(struct usb_gadget *g,
  97                 const char *dev_addr, const char *host_addr,
  98                 u8 ethaddr[ETH_ALEN], unsigned qmult, const char *netname);
  99
 100 /* netdev setup/teardown as directed by the gadget driver */
 101 /* gether_setup - initialize one ethernet-over-usb link
 102  * @g: gadget to associated with these links
 103  * @ethaddr: NULL, or a buffer in which the ethernet address of the
 104  *      host side of the link is recorded
 105  * Context: may sleep
 106  *
 107  * This sets up the single network link that may be exported by a
 108  * gadget driver using this framework.  The link layer addresses are
 109  * set up using module parameters.
 110  *
 111  * Returns a eth_dev pointer on success, or an ERR_PTR on failure
 112  */
 113 static inline struct eth_dev *gether_setup(struct usb_gadget *g,
 114                 const char *dev_addr, const char *host_addr,
 115                 u8 ethaddr[ETH_ALEN], unsigned qmult)
 116 {
 117         return gether_setup_name(g, dev_addr, host_addr, ethaddr, qmult, "usb");
 118 }
 119
 120 /*
 121  * variant of gether_setup_default that allows customizing
 122  * network device name
 123  */
 124 struct net_device *gether_setup_name_default(const char *netname);
 125
 126 /*
 127  * gether_register_netdev - register the net device
 128  * @net: net device to register
 129  *
 130  * Registers the net device associated with this ethernet-over-usb link
 131  *
 132  */
 133 int gether_register_netdev(struct net_device *net);
 134
 135 /* gether_setup_default - initialize one ethernet-over-usb link
 136  * Context: may sleep
 137  *
 138  * This sets up the single network link that may be exported by a
 139  * gadget driver using this framework.  The link layer addresses
 140  * are set to random values.
 141  *
 142  * Returns negative errno, or zero on success
 143  */
 144 static inline struct net_device *gether_setup_default(void)
 145 {
 146         return gether_setup_name_default("usb");
 147 }
 148
 149 /**
 150  * gether_set_gadget - initialize one ethernet-over-usb link with a gadget
 151  * @net: device representing this link
 152  * @g: the gadget to initialize with
 153  *
 154  * This associates one ethernet-over-usb link with a gadget.
 155  */
 156 void gether_set_gadget(struct net_device *net, struct usb_gadget *g);
 157
 158 /**
 159  * gether_set_dev_addr - initialize an ethernet-over-usb link with eth address
 160  * @net: device representing this link
 161  * @dev_addr: eth address of this device
 162  *
 163  * This sets the device-side Ethernet address of this ethernet-over-usb link
 164  * if dev_addr is correct.
 165  * Returns negative errno if the new address is incorrect.
 166  */
 167 int gether_set_dev_addr(struct net_device *net, const char *dev_addr);
 168
 169 /**
 170  * gether_get_dev_addr - get an ethernet-over-usb link eth address
 171  * @net: device representing this link
 172  * @dev_addr: place to store device's eth address
 173  * @len: length of the @dev_addr buffer
 174  *
 175  * This gets the device-side Ethernet address of this ethernet-over-usb link.
 176  * Returns zero on success, else negative errno.
 177  */
 178 int gether_get_dev_addr(struct net_device *net, char *dev_addr, int len);
 179
 180 /**
 181  * gether_set_host_addr - initialize an ethernet-over-usb link with host address
 182  * @net: device representing this link
 183  * @host_addr: eth address of the host
 184  *
 185  * This sets the host-side Ethernet address of this ethernet-over-usb link
 186  * if host_addr is correct.
 187  * Returns negative errno if the new address is incorrect.
 188  */
 189 int gether_set_host_addr(struct net_device *net, const char *host_addr);
 190
 191 /**
 192  * gether_get_host_addr - get an ethernet-over-usb link host address
 193  * @net: device representing this link
 194  * @host_addr: place to store eth address of the host
 195  * @len: length of the @host_addr buffer
 196  *
 197  * This gets the host-side Ethernet address of this ethernet-over-usb link.
 198  * Returns zero on success, else negative errno.
 199  */
 200 int gether_get_host_addr(struct net_device *net, char *host_addr, int len);
 201
 202 /**
 203  * gether_get_host_addr_cdc - get an ethernet-over-usb link host address
 204  * @net: device representing this link
 205  * @host_addr: place to store eth address of the host
 206  * @len: length of the @host_addr buffer
 207  *
 208  * This gets the CDC formatted host-side Ethernet address of this
 209  * ethernet-over-usb link.
 210  * Returns zero on success, else negative errno.
 211  */
 212 int gether_get_host_addr_cdc(struct net_device *net, char *host_addr, int len);
 213
 214 /**
 215  * gether_get_host_addr_u8 - get an ethernet-over-usb link host address
 216  * @net: device representing this link
 217  * @host_mac: place to store the eth address of the host
 218  *
 219  * This gets the binary formatted host-side Ethernet address of this
 220  * ethernet-over-usb link.
 221  */
 222 void gether_get_host_addr_u8(struct net_device *net, u8 host_mac[ETH_ALEN]);
 223
 224 /**
 225  * gether_set_qmult - initialize an ethernet-over-usb link with a multiplier
 226  * @net: device representing this link
 227  * @qmult: queue multiplier
 228  *
 229  * This sets the queue length multiplier of this ethernet-over-usb link.
 230  * For higher speeds use longer queues.
 231  */
 232 void gether_set_qmult(struct net_device *net, unsigned qmult);
 233
 234 /**
 235  * gether_get_qmult - get an ethernet-over-usb link multiplier
 236  * @net: device representing this link
 237  *
 238  * This gets the queue length multiplier of this ethernet-over-usb link.
 239  */
 240 unsigned gether_get_qmult(struct net_device *net);
 241
 242 /**
 243  * gether_get_ifname - get an ethernet-over-usb link interface name
 244  * @net: device representing this link
 245  * @name: place to store the interface name
 246  * @len: length of the @name buffer
 247  *
 248  * This gets the interface name of this ethernet-over-usb link.
 249  * Returns zero on success, else negative errno.
 250  */
 251 int gether_get_ifname(struct net_device *net, char *name, int len);
 252
 253 void gether_cleanup(struct eth_dev *dev);
 254
 255 /* connect/disconnect is handled by individual functions */
 256 struct net_device *gether_connect(struct gether *);
 257 void gether_disconnect(struct gether *);
 258
 259 /* Some controllers can't support CDC Ethernet (ECM) ... */
 260 static inline bool can_support_ecm(struct usb_gadget *gadget)
 261 {
 262         if (!gadget_supports_altsettings(gadget))
 263                 return false;
 264
 265         /* Everything else is *presumably* fine ... but this is a bit
 266          * chancy, so be **CERTAIN** there are no hardware issues with
 267          * your controller.  Add it above if it can't handle CDC.
 268          */
 269         return true;
 270 }
 271
 272 #endif /* __U_ETHER_H */