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