drivers/net/wimax/i2400m/netdev.c

   1 /*
   2  * Intel Wireless WiMAX Connection 2400m
   3  * Glue with the networking stack
   4  *
   5  *
   6  * Copyright (C) 2007 Intel Corporation <linux-wimax@intel.com>
   7  * Yanir Lubetkin <yanirx.lubetkin@intel.com>
   8  * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License version
  12  * 2 as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  22  * 02110-1301, USA.
  23  *
  24  *
  25  * This implements an ethernet device for the i2400m.
  26  *
  27  * We fake being an ethernet device to simplify the support from user
  28  * space and from the other side. The world is (sadly) configured to
  29  * take in only Ethernet devices...
  30  *
  31  * Because of this, when using firmwares <= v1.3, there is an
  32  * copy-each-rxed-packet overhead on the RX path. Each IP packet has
  33  * to be reallocated to add an ethernet header (as there is no space
  34  * in what we get from the device). This is a known drawback and
  35  * firmwares >= 1.4 add header space that can be used to insert the
  36  * ethernet header without having to reallocate and copy.
  37  *
  38  * TX error handling is tricky; because we have to FIFO/queue the
  39  * buffers for transmission (as the hardware likes it aggregated), we
  40  * just give the skb to the TX subsystem and by the time it is
  41  * transmitted, we have long forgotten about it. So we just don't care
  42  * too much about it.
  43  *
  44  * Note that when the device is in idle mode with the basestation, we
  45  * need to negotiate coming back up online. That involves negotiation
  46  * and possible user space interaction. Thus, we defer to a workqueue
  47  * to do all that. By default, we only queue a single packet and drop
  48  * the rest, as potentially the time to go back from idle to normal is
  49  * long.
  50  *
  51  * ROADMAP
  52  *
  53  * i2400m_open         Called on ifconfig up
  54  * i2400m_stop         Called on ifconfig down
  55  *
  56  * i2400m_hard_start_xmit Called by the network stack to send a packet
  57  *   i2400m_net_wake_tx   Wake up device from basestation-IDLE & TX
  58  *     i2400m_wake_tx_work
  59  *       i2400m_cmd_exit_idle
  60  *       i2400m_tx
  61  *   i2400m_net_tx        TX a data frame
  62  *     i2400m_tx
  63  *
  64  * i2400m_change_mtu      Called on ifconfig mtu XXX
  65  *
  66  * i2400m_tx_timeout      Called when the device times out
  67  *
  68  * i2400m_net_rx          Called by the RX code when a data frame is
  69  *                        available (firmware <= 1.3)
  70  * i2400m_net_erx         Called by the RX code when a data frame is
  71  *                        available (firmware >= 1.4).
  72  * i2400m_netdev_setup    Called to setup all the netdev stuff from
  73  *                        alloc_netdev.
  74  */
  75 #include <linux/if_arp.h>
  76 #include <linux/slab.h>
  77 #include <linux/netdevice.h>
  78 #include <linux/ethtool.h>
  79 #include <linux/export.h>
  80 #include "i2400m.h"
  81
  82
  83 #define D_SUBMODULE netdev
  84 #include "debug-levels.h"
  85
  86 enum {
  87 /* netdev interface */
  88         /* 20 secs? yep, this is the maximum timeout that the device
  89          * might take to get out of IDLE / negotiate it with the base
  90          * station. We add 1sec for good measure. */
  91         I2400M_TX_TIMEOUT = 21 * HZ,
  92         /*
  93          * Experimentation has determined that, 20 to be a good value
  94          * for minimizing the jitter in the throughput.
  95          */
  96         I2400M_TX_QLEN = 20,
  97 };
  98
  99
 100 static
 101 int i2400m_open(struct net_device *net_dev)
 102 {
 103         int result;
 104         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 105         struct device *dev = i2400m_dev(i2400m);
 106
 107         d_fnstart(3, dev, "(net_dev %p [i2400m %p])\n", net_dev, i2400m);
 108         /* Make sure we wait until init is complete... */
 109         mutex_lock(&i2400m->init_mutex);
 110         if (i2400m->updown)
 111                 result = 0;
 112         else
 113                 result = -EBUSY;
 114         mutex_unlock(&i2400m->init_mutex);
 115         d_fnend(3, dev, "(net_dev %p [i2400m %p]) = %d\n",
 116                 net_dev, i2400m, result);
 117         return result;
 118 }
 119
 120
 121 static
 122 int i2400m_stop(struct net_device *net_dev)
 123 {
 124         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 125         struct device *dev = i2400m_dev(i2400m);
 126
 127         d_fnstart(3, dev, "(net_dev %p [i2400m %p])\n", net_dev, i2400m);
 128         i2400m_net_wake_stop(i2400m);
 129         d_fnend(3, dev, "(net_dev %p [i2400m %p]) = 0\n", net_dev, i2400m);
 130         return 0;
 131 }
 132
 133
 134 /*
 135  * Wake up the device and transmit a held SKB, then restart the net queue
 136  *
 137  * When the device goes into basestation-idle mode, we need to tell it
 138  * to exit that mode; it will negotiate with the base station, user
 139  * space may have to intervene to rehandshake crypto and then tell us
 140  * when it is ready to transmit the packet we have "queued". Still we
 141  * need to give it sometime after it reports being ok.
 142  *
 143  * On error, there is not much we can do. If the error was on TX, we
 144  * still wake the queue up to see if the next packet will be luckier.
 145  *
 146  * If _cmd_exit_idle() fails...well, it could be many things; most
 147  * commonly it is that something else took the device out of IDLE mode
 148  * (for example, the base station). In that case we get an -EILSEQ and
 149  * we are just going to ignore that one. If the device is back to
 150  * connected, then fine -- if it is someother state, the packet will
 151  * be dropped anyway.
 152  */
 153 void i2400m_wake_tx_work(struct work_struct *ws)
 154 {
 155         int result;
 156         struct i2400m *i2400m = container_of(ws, struct i2400m, wake_tx_ws);
 157         struct net_device *net_dev = i2400m->wimax_dev.net_dev;
 158         struct device *dev = i2400m_dev(i2400m);
 159         struct sk_buff *skb;
 160         unsigned long flags;
 161
 162         spin_lock_irqsave(&i2400m->tx_lock, flags);
 163         skb = i2400m->wake_tx_skb;
 164         i2400m->wake_tx_skb = NULL;
 165         spin_unlock_irqrestore(&i2400m->tx_lock, flags);
 166
 167         d_fnstart(3, dev, "(ws %p i2400m %p skb %p)\n", ws, i2400m, skb);
 168         result = -EINVAL;
 169         if (skb == NULL) {
 170                 dev_err(dev, "WAKE&TX: skb disappeared!\n");
 171                 goto out_put;
 172         }
 173         /* If we have, somehow, lost the connection after this was
 174          * queued, don't do anything; this might be the device got
 175          * reset or just disconnected. */
 176         if (unlikely(!netif_carrier_ok(net_dev)))
 177                 goto out_kfree;
 178         result = i2400m_cmd_exit_idle(i2400m);
 179         if (result == -EILSEQ)
 180                 result = 0;
 181         if (result < 0) {
 182                 dev_err(dev, "WAKE&TX: device didn't get out of idle: "
 183                         "%d - resetting\n", result);
 184                 i2400m_reset(i2400m, I2400M_RT_BUS);
 185                 goto error;
 186         }
 187         result = wait_event_timeout(i2400m->state_wq,
 188                                     i2400m->state != I2400M_SS_IDLE,
 189                                     net_dev->watchdog_timeo - HZ/2);
 190         if (result == 0)
 191                 result = -ETIMEDOUT;
 192         if (result < 0) {
 193                 dev_err(dev, "WAKE&TX: error waiting for device to exit IDLE: "
 194                         "%d - resetting\n", result);
 195                 i2400m_reset(i2400m, I2400M_RT_BUS);
 196                 goto error;
 197         }
 198         msleep(20);     /* device still needs some time or it drops it */
 199         result = i2400m_tx(i2400m, skb->data, skb->len, I2400M_PT_DATA);
 200 error:
 201         netif_wake_queue(net_dev);
 202 out_kfree:
 203         kfree_skb(skb); /* refcount transferred by _hard_start_xmit() */
 204 out_put:
 205         i2400m_put(i2400m);
 206         d_fnend(3, dev, "(ws %p i2400m %p skb %p) = void [%d]\n",
 207                 ws, i2400m, skb, result);
 208 }
 209
 210
 211 /*
 212  * Prepare the data payload TX header
 213  *
 214  * The i2400m expects a 4 byte header in front of a data packet.
 215  *
 216  * Because we pretend to be an ethernet device, this packet comes with
 217  * an ethernet header. Pull it and push our header.
 218  */
 219 static
 220 void i2400m_tx_prep_header(struct sk_buff *skb)
 221 {
 222         struct i2400m_pl_data_hdr *pl_hdr;
 223         skb_pull(skb, ETH_HLEN);
 224         pl_hdr = (struct i2400m_pl_data_hdr *) skb_push(skb, sizeof(*pl_hdr));
 225         pl_hdr->reserved = 0;
 226 }
 227
 228
 229
 230 /*
 231  * Cleanup resources acquired during i2400m_net_wake_tx()
 232  *
 233  * This is called by __i2400m_dev_stop and means we have to make sure
 234  * the workqueue is flushed from any pending work.
 235  */
 236 void i2400m_net_wake_stop(struct i2400m *i2400m)
 237 {
 238         struct device *dev = i2400m_dev(i2400m);
 239         struct sk_buff *wake_tx_skb;
 240         unsigned long flags;
 241
 242         d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
 243         /*
 244          * See i2400m_hard_start_xmit(), references are taken there and
 245          * here we release them if the packet was still pending.
 246          */
 247         cancel_work_sync(&i2400m->wake_tx_ws);
 248
 249         spin_lock_irqsave(&i2400m->tx_lock, flags);
 250         wake_tx_skb = i2400m->wake_tx_skb;
 251         i2400m->wake_tx_skb = NULL;
 252         spin_unlock_irqrestore(&i2400m->tx_lock, flags);
 253
 254         if (wake_tx_skb) {
 255                 i2400m_put(i2400m);
 256                 kfree_skb(wake_tx_skb);
 257         }
 258
 259         d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
 260 }
 261
 262
 263 /*
 264  * TX an skb to an idle device
 265  *
 266  * When the device is in basestation-idle mode, we need to wake it up
 267  * and then TX. So we queue a work_struct for doing so.
 268  *
 269  * We need to get an extra ref for the skb (so it is not dropped), as
 270  * well as be careful not to queue more than one request (won't help
 271  * at all). If more than one request comes or there are errors, we
 272  * just drop the packets (see i2400m_hard_start_xmit()).
 273  */
 274 static
 275 int i2400m_net_wake_tx(struct i2400m *i2400m, struct net_device *net_dev,
 276                        struct sk_buff *skb)
 277 {
 278         int result;
 279         struct device *dev = i2400m_dev(i2400m);
 280         unsigned long flags;
 281
 282         d_fnstart(3, dev, "(skb %p net_dev %p)\n", skb, net_dev);
 283         if (net_ratelimit()) {
 284                 d_printf(3, dev, "WAKE&NETTX: "
 285                          "skb %p sending %d bytes to radio\n",
 286                          skb, skb->len);
 287                 d_dump(4, dev, skb->data, skb->len);
 288         }
 289         /* We hold a ref count for i2400m and skb, so when
 290          * stopping() the device, we need to cancel that work
 291          * and if pending, release those resources. */
 292         result = 0;
 293         spin_lock_irqsave(&i2400m->tx_lock, flags);
 294         if (!i2400m->wake_tx_skb) {
 295                 netif_stop_queue(net_dev);
 296                 i2400m_get(i2400m);
 297                 i2400m->wake_tx_skb = skb_get(skb);     /* transfer ref count */
 298                 i2400m_tx_prep_header(skb);
 299                 result = schedule_work(&i2400m->wake_tx_ws);
 300                 WARN_ON(result == 0);
 301         }
 302         spin_unlock_irqrestore(&i2400m->tx_lock, flags);
 303         if (result == 0) {
 304                 /* Yes, this happens even if we stopped the
 305                  * queue -- blame the queue disciplines that
 306                  * queue without looking -- I guess there is a reason
 307                  * for that. */
 308                 if (net_ratelimit())
 309                         d_printf(1, dev, "NETTX: device exiting idle, "
 310                                  "dropping skb %p, queue running %d\n",
 311                                  skb, netif_queue_stopped(net_dev));
 312                 result = -EBUSY;
 313         }
 314         d_fnend(3, dev, "(skb %p net_dev %p) = %d\n", skb, net_dev, result);
 315         return result;
 316 }
 317
 318
 319 /*
 320  * Transmit a packet to the base station on behalf of the network stack.
 321  *
 322  * Returns: 0 if ok, < 0 errno code on error.
 323  *
 324  * We need to pull the ethernet header and add the hardware header,
 325  * which is currently set to all zeroes and reserved.
 326  */
 327 static
 328 int i2400m_net_tx(struct i2400m *i2400m, struct net_device *net_dev,
 329                   struct sk_buff *skb)
 330 {
 331         int result;
 332         struct device *dev = i2400m_dev(i2400m);
 333
 334         d_fnstart(3, dev, "(i2400m %p net_dev %p skb %p)\n",
 335                   i2400m, net_dev, skb);
 336         /* FIXME: check eth hdr, only IPv4 is routed by the device as of now */
 337         netif_trans_update(net_dev);
 338         i2400m_tx_prep_header(skb);
 339         d_printf(3, dev, "NETTX: skb %p sending %d bytes to radio\n",
 340                  skb, skb->len);
 341         d_dump(4, dev, skb->data, skb->len);
 342         result = i2400m_tx(i2400m, skb->data, skb->len, I2400M_PT_DATA);
 343         d_fnend(3, dev, "(i2400m %p net_dev %p skb %p) = %d\n",
 344                 i2400m, net_dev, skb, result);
 345         return result;
 346 }
 347
 348
 349 /*
 350  * Transmit a packet to the base station on behalf of the network stack
 351  *
 352  *
 353  * Returns: NETDEV_TX_OK (always, even in case of error)
 354  *
 355  * In case of error, we just drop it. Reasons:
 356  *
 357  *  - we add a hw header to each skb, and if the network stack
 358  *    retries, we have no way to know if that skb has it or not.
 359  *
 360  *  - network protocols have their own drop-recovery mechanisms
 361  *
 362  *  - there is not much else we can do
 363  *
 364  * If the device is idle, we need to wake it up; that is an operation
 365  * that will sleep. See i2400m_net_wake_tx() for details.
 366  */
 367 static
 368 netdev_tx_t i2400m_hard_start_xmit(struct sk_buff *skb,
 369                                          struct net_device *net_dev)
 370 {
 371         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 372         struct device *dev = i2400m_dev(i2400m);
 373         int result = -1;
 374
 375         d_fnstart(3, dev, "(skb %p net_dev %p)\n", skb, net_dev);
 376
 377         if (skb_cow_head(skb, 0))
 378                 goto drop;
 379
 380         if (i2400m->state == I2400M_SS_IDLE)
 381                 result = i2400m_net_wake_tx(i2400m, net_dev, skb);
 382         else
 383                 result = i2400m_net_tx(i2400m, net_dev, skb);
 384         if (result <  0) {
 385 drop:
 386                 net_dev->stats.tx_dropped++;
 387         } else {
 388                 net_dev->stats.tx_packets++;
 389                 net_dev->stats.tx_bytes += skb->len;
 390         }
 391         dev_kfree_skb(skb);
 392         d_fnend(3, dev, "(skb %p net_dev %p) = %d\n", skb, net_dev, result);
 393         return NETDEV_TX_OK;
 394 }
 395
 396
 397 static
 398 void i2400m_tx_timeout(struct net_device *net_dev)
 399 {
 400         /*
 401          * We might want to kick the device
 402          *
 403          * There is not much we can do though, as the device requires
 404          * that we send the data aggregated. By the time we receive
 405          * this, there might be data pending to be sent or not...
 406          */
 407         net_dev->stats.tx_errors++;
 408 }
 409
 410
 411 /*
 412  * Create a fake ethernet header
 413  *
 414  * For emulating an ethernet device, every received IP header has to
 415  * be prefixed with an ethernet header. Fake it with the given
 416  * protocol.
 417  */
 418 static
 419 void i2400m_rx_fake_eth_header(struct net_device *net_dev,
 420                                void *_eth_hdr, __be16 protocol)
 421 {
 422         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 423         struct ethhdr *eth_hdr = _eth_hdr;
 424
 425         memcpy(eth_hdr->h_dest, net_dev->dev_addr, sizeof(eth_hdr->h_dest));
 426         memcpy(eth_hdr->h_source, i2400m->src_mac_addr,
 427                sizeof(eth_hdr->h_source));
 428         eth_hdr->h_proto = protocol;
 429 }
 430
 431
 432 /*
 433  * i2400m_net_rx - pass a network packet to the stack
 434  *
 435  * @i2400m: device instance
 436  * @skb_rx: the skb where the buffer pointed to by @buf is
 437  * @i: 1 if payload is the only one
 438  * @buf: pointer to the buffer containing the data
 439  * @len: buffer's length
 440  *
 441  * This is only used now for the v1.3 firmware. It will be deprecated
 442  * in >= 2.6.31.
 443  *
 444  * Note that due to firmware limitations, we don't have space to add
 445  * an ethernet header, so we need to copy each packet. Firmware
 446  * versions >= v1.4 fix this [see i2400m_net_erx()].
 447  *
 448  * We just clone the skb and set it up so that it's skb->data pointer
 449  * points to "buf" and it's length.
 450  *
 451  * Note that if the payload is the last (or the only one) in a
 452  * multi-payload message, we don't clone the SKB but just reuse it.
 453  *
 454  * This function is normally run from a thread context. However, we
 455  * still use netif_rx() instead of netif_receive_skb() as was
 456  * recommended in the mailing list. Reason is in some stress tests
 457  * when sending/receiving a lot of data we seem to hit a softlock in
 458  * the kernel's TCP implementation [aroudn tcp_delay_timer()]. Using
 459  * netif_rx() took care of the issue.
 460  *
 461  * This is, of course, still open to do more research on why running
 462  * with netif_receive_skb() hits this softlock. FIXME.
 463  *
 464  * FIXME: currently we don't do any efforts at distinguishing if what
 465  * we got was an IPv4 or IPv6 header, to setup the protocol field
 466  * correctly.
 467  */
 468 void i2400m_net_rx(struct i2400m *i2400m, struct sk_buff *skb_rx,
 469                    unsigned i, const void *buf, int buf_len)
 470 {
 471         struct net_device *net_dev = i2400m->wimax_dev.net_dev;
 472         struct device *dev = i2400m_dev(i2400m);
 473         struct sk_buff *skb;
 474
 475         d_fnstart(2, dev, "(i2400m %p buf %p buf_len %d)\n",
 476                   i2400m, buf, buf_len);
 477         if (i) {
 478                 skb = skb_get(skb_rx);
 479                 d_printf(2, dev, "RX: reusing first payload skb %p\n", skb);
 480                 skb_pull(skb, buf - (void *) skb->data);
 481                 skb_trim(skb, (void *) skb_end_pointer(skb) - buf);
 482         } else {
 483                 /* Yes, this is bad -- a lot of overhead -- see
 484                  * comments at the top of the file */
 485                 skb = __netdev_alloc_skb(net_dev, buf_len, GFP_KERNEL);
 486                 if (skb == NULL) {
 487                         dev_err(dev, "NETRX: no memory to realloc skb\n");
 488                         net_dev->stats.rx_dropped++;
 489                         goto error_skb_realloc;
 490                 }
 491                 memcpy(skb_put(skb, buf_len), buf, buf_len);
 492         }
 493         i2400m_rx_fake_eth_header(i2400m->wimax_dev.net_dev,
 494                                   skb->data - ETH_HLEN,
 495                                   cpu_to_be16(ETH_P_IP));
 496         skb_set_mac_header(skb, -ETH_HLEN);
 497         skb->dev = i2400m->wimax_dev.net_dev;
 498         skb->protocol = htons(ETH_P_IP);
 499         net_dev->stats.rx_packets++;
 500         net_dev->stats.rx_bytes += buf_len;
 501         d_printf(3, dev, "NETRX: receiving %d bytes to network stack\n",
 502                 buf_len);
 503         d_dump(4, dev, buf, buf_len);
 504         netif_rx_ni(skb);       /* see notes in function header */
 505 error_skb_realloc:
 506         d_fnend(2, dev, "(i2400m %p buf %p buf_len %d) = void\n",
 507                 i2400m, buf, buf_len);
 508 }
 509
 510
 511 /*
 512  * i2400m_net_erx - pass a network packet to the stack (extended version)
 513  *
 514  * @i2400m: device descriptor
 515  * @skb: the skb where the packet is - the skb should be set to point
 516  *     at the IP packet; this function will add ethernet headers if
 517  *     needed.
 518  * @cs: packet type
 519  *
 520  * This is only used now for firmware >= v1.4. Note it is quite
 521  * similar to i2400m_net_rx() (used only for v1.3 firmware).
 522  *
 523  * This function is normally run from a thread context. However, we
 524  * still use netif_rx() instead of netif_receive_skb() as was
 525  * recommended in the mailing list. Reason is in some stress tests
 526  * when sending/receiving a lot of data we seem to hit a softlock in
 527  * the kernel's TCP implementation [aroudn tcp_delay_timer()]. Using
 528  * netif_rx() took care of the issue.
 529  *
 530  * This is, of course, still open to do more research on why running
 531  * with netif_receive_skb() hits this softlock. FIXME.
 532  */
 533 void i2400m_net_erx(struct i2400m *i2400m, struct sk_buff *skb,
 534                     enum i2400m_cs cs)
 535 {
 536         struct net_device *net_dev = i2400m->wimax_dev.net_dev;
 537         struct device *dev = i2400m_dev(i2400m);
 538         int protocol;
 539
 540         d_fnstart(2, dev, "(i2400m %p skb %p [%u] cs %d)\n",
 541                   i2400m, skb, skb->len, cs);
 542         switch(cs) {
 543         case I2400M_CS_IPV4_0:
 544         case I2400M_CS_IPV4:
 545                 protocol = ETH_P_IP;
 546                 i2400m_rx_fake_eth_header(i2400m->wimax_dev.net_dev,
 547                                           skb->data - ETH_HLEN,
 548                                           cpu_to_be16(ETH_P_IP));
 549                 skb_set_mac_header(skb, -ETH_HLEN);
 550                 skb->dev = i2400m->wimax_dev.net_dev;
 551                 skb->protocol = htons(ETH_P_IP);
 552                 net_dev->stats.rx_packets++;
 553                 net_dev->stats.rx_bytes += skb->len;
 554                 break;
 555         default:
 556                 dev_err(dev, "ERX: BUG? CS type %u unsupported\n", cs);
 557                 goto error;
 558
 559         }
 560         d_printf(3, dev, "ERX: receiving %d bytes to the network stack\n",
 561                  skb->len);
 562         d_dump(4, dev, skb->data, skb->len);
 563         netif_rx_ni(skb);       /* see notes in function header */
 564 error:
 565         d_fnend(2, dev, "(i2400m %p skb %p [%u] cs %d) = void\n",
 566                 i2400m, skb, skb->len, cs);
 567 }
 568
 569 static const struct net_device_ops i2400m_netdev_ops = {
 570         .ndo_open = i2400m_open,
 571         .ndo_stop = i2400m_stop,
 572         .ndo_start_xmit = i2400m_hard_start_xmit,
 573         .ndo_tx_timeout = i2400m_tx_timeout,
 574 };
 575
 576 static void i2400m_get_drvinfo(struct net_device *net_dev,
 577                                struct ethtool_drvinfo *info)
 578 {
 579         struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 580
 581         strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
 582         strlcpy(info->fw_version, i2400m->fw_name ? : "",
 583                 sizeof(info->fw_version));
 584         if (net_dev->dev.parent)
 585                 strlcpy(info->bus_info, dev_name(net_dev->dev.parent),
 586                         sizeof(info->bus_info));
 587 }
 588
 589 static const struct ethtool_ops i2400m_ethtool_ops = {
 590         .get_drvinfo = i2400m_get_drvinfo,
 591         .get_link = ethtool_op_get_link,
 592 };
 593
 594 /**
 595  * i2400m_netdev_setup - Setup setup @net_dev's i2400m private data
 596  *
 597  * Called by alloc_netdev()
 598  */
 599 void i2400m_netdev_setup(struct net_device *net_dev)
 600 {
 601         d_fnstart(3, NULL, "(net_dev %p)\n", net_dev);
 602         ether_setup(net_dev);
 603         net_dev->mtu = I2400M_MAX_MTU;
 604         net_dev->min_mtu = 0;
 605         net_dev->max_mtu = I2400M_MAX_MTU;
 606         net_dev->tx_queue_len = I2400M_TX_QLEN;
 607         net_dev->features =
 608                   NETIF_F_VLAN_CHALLENGED
 609                 | NETIF_F_HIGHDMA;
 610         net_dev->flags =
 611                 IFF_NOARP               /* i2400m is apure IP device */
 612                 & (~IFF_BROADCAST       /* i2400m is P2P */
 613                    & ~IFF_MULTICAST);
 614         net_dev->watchdog_timeo = I2400M_TX_TIMEOUT;
 615         net_dev->netdev_ops = &i2400m_netdev_ops;
 616         net_dev->ethtool_ops = &i2400m_ethtool_ops;
 617         d_fnend(3, NULL, "(net_dev %p) = void\n", net_dev);
 618 }
 619 EXPORT_SYMBOL_GPL(i2400m_netdev_setup);
 620