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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel Wireless WiMAX Connection 2400m
4  * Glue with the networking stack
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 implements an ethernet device for the i2400m.
11  *
12  * We fake being an ethernet device to simplify the support from user
13  * space and from the other side. The world is (sadly) configured to
14  * take in only Ethernet devices...
15  *
16  * Because of this, when using firmwares <= v1.3, there is an
17  * copy-each-rxed-packet overhead on the RX path. Each IP packet has
18  * to be reallocated to add an ethernet header (as there is no space
19  * in what we get from the device). This is a known drawback and
20  * firmwares >= 1.4 add header space that can be used to insert the
21  * ethernet header without having to reallocate and copy.
22  *
23  * TX error handling is tricky; because we have to FIFO/queue the
24  * buffers for transmission (as the hardware likes it aggregated), we
25  * just give the skb to the TX subsystem and by the time it is
26  * transmitted, we have long forgotten about it. So we just don't care
27  * too much about it.
28  *
29  * Note that when the device is in idle mode with the basestation, we
30  * need to negotiate coming back up online. That involves negotiation
31  * and possible user space interaction. Thus, we defer to a workqueue
32  * to do all that. By default, we only queue a single packet and drop
33  * the rest, as potentially the time to go back from idle to normal is
34  * long.
35  *
36  * ROADMAP
37  *
38  * i2400m_open         Called on ifconfig up
39  * i2400m_stop         Called on ifconfig down
40  *
41  * i2400m_hard_start_xmit Called by the network stack to send a packet
42  *   i2400m_net_wake_tx	  Wake up device from basestation-IDLE & TX
43  *     i2400m_wake_tx_work
44  *       i2400m_cmd_exit_idle
45  *       i2400m_tx
46  *   i2400m_net_tx        TX a data frame
47  *     i2400m_tx
48  *
49  * i2400m_change_mtu      Called on ifconfig mtu XXX
50  *
51  * i2400m_tx_timeout      Called when the device times out
52  *
53  * i2400m_net_rx          Called by the RX code when a data frame is
54  *                        available (firmware <= 1.3)
55  * i2400m_net_erx         Called by the RX code when a data frame is
56  *                        available (firmware >= 1.4).
57  * i2400m_netdev_setup    Called to setup all the netdev stuff from
58  *                        alloc_netdev.
59  */
60 #include <linux/if_arp.h>
61 #include <linux/slab.h>
62 #include <linux/netdevice.h>
63 #include <linux/ethtool.h>
64 #include <linux/export.h>
65 #include "i2400m.h"
66 
67 
68 #define D_SUBMODULE netdev
69 #include "debug-levels.h"
70 
71 enum {
72 /* netdev interface */
73 	/* 20 secs? yep, this is the maximum timeout that the device
74 	 * might take to get out of IDLE / negotiate it with the base
75 	 * station. We add 1sec for good measure. */
76 	I2400M_TX_TIMEOUT = 21 * HZ,
77 	/*
78 	 * Experimentation has determined that, 20 to be a good value
79 	 * for minimizing the jitter in the throughput.
80 	 */
81 	I2400M_TX_QLEN = 20,
82 };
83 
84 
85 static
i2400m_open(struct net_device * net_dev)86 int i2400m_open(struct net_device *net_dev)
87 {
88 	int result;
89 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
90 	struct device *dev = i2400m_dev(i2400m);
91 
92 	d_fnstart(3, dev, "(net_dev %p [i2400m %p])\n", net_dev, i2400m);
93 	/* Make sure we wait until init is complete... */
94 	mutex_lock(&i2400m->init_mutex);
95 	if (i2400m->updown)
96 		result = 0;
97 	else
98 		result = -EBUSY;
99 	mutex_unlock(&i2400m->init_mutex);
100 	d_fnend(3, dev, "(net_dev %p [i2400m %p]) = %d\n",
101 		net_dev, i2400m, result);
102 	return result;
103 }
104 
105 
106 static
i2400m_stop(struct net_device * net_dev)107 int i2400m_stop(struct net_device *net_dev)
108 {
109 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
110 	struct device *dev = i2400m_dev(i2400m);
111 
112 	d_fnstart(3, dev, "(net_dev %p [i2400m %p])\n", net_dev, i2400m);
113 	i2400m_net_wake_stop(i2400m);
114 	d_fnend(3, dev, "(net_dev %p [i2400m %p]) = 0\n", net_dev, i2400m);
115 	return 0;
116 }
117 
118 
119 /*
120  * Wake up the device and transmit a held SKB, then restart the net queue
121  *
122  * When the device goes into basestation-idle mode, we need to tell it
123  * to exit that mode; it will negotiate with the base station, user
124  * space may have to intervene to rehandshake crypto and then tell us
125  * when it is ready to transmit the packet we have "queued". Still we
126  * need to give it sometime after it reports being ok.
127  *
128  * On error, there is not much we can do. If the error was on TX, we
129  * still wake the queue up to see if the next packet will be luckier.
130  *
131  * If _cmd_exit_idle() fails...well, it could be many things; most
132  * commonly it is that something else took the device out of IDLE mode
133  * (for example, the base station). In that case we get an -EILSEQ and
134  * we are just going to ignore that one. If the device is back to
135  * connected, then fine -- if it is someother state, the packet will
136  * be dropped anyway.
137  */
i2400m_wake_tx_work(struct work_struct * ws)138 void i2400m_wake_tx_work(struct work_struct *ws)
139 {
140 	int result;
141 	struct i2400m *i2400m = container_of(ws, struct i2400m, wake_tx_ws);
142 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
143 	struct device *dev = i2400m_dev(i2400m);
144 	struct sk_buff *skb;
145 	unsigned long flags;
146 
147 	spin_lock_irqsave(&i2400m->tx_lock, flags);
148 	skb = i2400m->wake_tx_skb;
149 	i2400m->wake_tx_skb = NULL;
150 	spin_unlock_irqrestore(&i2400m->tx_lock, flags);
151 
152 	d_fnstart(3, dev, "(ws %p i2400m %p skb %p)\n", ws, i2400m, skb);
153 	result = -EINVAL;
154 	if (skb == NULL) {
155 		dev_err(dev, "WAKE&TX: skb disappeared!\n");
156 		goto out_put;
157 	}
158 	/* If we have, somehow, lost the connection after this was
159 	 * queued, don't do anything; this might be the device got
160 	 * reset or just disconnected. */
161 	if (unlikely(!netif_carrier_ok(net_dev)))
162 		goto out_kfree;
163 	result = i2400m_cmd_exit_idle(i2400m);
164 	if (result == -EILSEQ)
165 		result = 0;
166 	if (result < 0) {
167 		dev_err(dev, "WAKE&TX: device didn't get out of idle: "
168 			"%d - resetting\n", result);
169 		i2400m_reset(i2400m, I2400M_RT_BUS);
170 		goto error;
171 	}
172 	result = wait_event_timeout(i2400m->state_wq,
173 				    i2400m->state != I2400M_SS_IDLE,
174 				    net_dev->watchdog_timeo - HZ/2);
175 	if (result == 0)
176 		result = -ETIMEDOUT;
177 	if (result < 0) {
178 		dev_err(dev, "WAKE&TX: error waiting for device to exit IDLE: "
179 			"%d - resetting\n", result);
180 		i2400m_reset(i2400m, I2400M_RT_BUS);
181 		goto error;
182 	}
183 	msleep(20);	/* device still needs some time or it drops it */
184 	result = i2400m_tx(i2400m, skb->data, skb->len, I2400M_PT_DATA);
185 error:
186 	netif_wake_queue(net_dev);
187 out_kfree:
188 	kfree_skb(skb);	/* refcount transferred by _hard_start_xmit() */
189 out_put:
190 	i2400m_put(i2400m);
191 	d_fnend(3, dev, "(ws %p i2400m %p skb %p) = void [%d]\n",
192 		ws, i2400m, skb, result);
193 }
194 
195 
196 /*
197  * Prepare the data payload TX header
198  *
199  * The i2400m expects a 4 byte header in front of a data packet.
200  *
201  * Because we pretend to be an ethernet device, this packet comes with
202  * an ethernet header. Pull it and push our header.
203  */
204 static
i2400m_tx_prep_header(struct sk_buff * skb)205 void i2400m_tx_prep_header(struct sk_buff *skb)
206 {
207 	struct i2400m_pl_data_hdr *pl_hdr;
208 	skb_pull(skb, ETH_HLEN);
209 	pl_hdr = skb_push(skb, sizeof(*pl_hdr));
210 	pl_hdr->reserved = 0;
211 }
212 
213 
214 
215 /*
216  * Cleanup resources acquired during i2400m_net_wake_tx()
217  *
218  * This is called by __i2400m_dev_stop and means we have to make sure
219  * the workqueue is flushed from any pending work.
220  */
i2400m_net_wake_stop(struct i2400m * i2400m)221 void i2400m_net_wake_stop(struct i2400m *i2400m)
222 {
223 	struct device *dev = i2400m_dev(i2400m);
224 	struct sk_buff *wake_tx_skb;
225 	unsigned long flags;
226 
227 	d_fnstart(3, dev, "(i2400m %p)\n", i2400m);
228 	/*
229 	 * See i2400m_hard_start_xmit(), references are taken there and
230 	 * here we release them if the packet was still pending.
231 	 */
232 	cancel_work_sync(&i2400m->wake_tx_ws);
233 
234 	spin_lock_irqsave(&i2400m->tx_lock, flags);
235 	wake_tx_skb = i2400m->wake_tx_skb;
236 	i2400m->wake_tx_skb = NULL;
237 	spin_unlock_irqrestore(&i2400m->tx_lock, flags);
238 
239 	if (wake_tx_skb) {
240 		i2400m_put(i2400m);
241 		kfree_skb(wake_tx_skb);
242 	}
243 
244 	d_fnend(3, dev, "(i2400m %p) = void\n", i2400m);
245 }
246 
247 
248 /*
249  * TX an skb to an idle device
250  *
251  * When the device is in basestation-idle mode, we need to wake it up
252  * and then TX. So we queue a work_struct for doing so.
253  *
254  * We need to get an extra ref for the skb (so it is not dropped), as
255  * well as be careful not to queue more than one request (won't help
256  * at all). If more than one request comes or there are errors, we
257  * just drop the packets (see i2400m_hard_start_xmit()).
258  */
259 static
i2400m_net_wake_tx(struct i2400m * i2400m,struct net_device * net_dev,struct sk_buff * skb)260 int i2400m_net_wake_tx(struct i2400m *i2400m, struct net_device *net_dev,
261 		       struct sk_buff *skb)
262 {
263 	int result;
264 	struct device *dev = i2400m_dev(i2400m);
265 	unsigned long flags;
266 
267 	d_fnstart(3, dev, "(skb %p net_dev %p)\n", skb, net_dev);
268 	if (net_ratelimit()) {
269 		d_printf(3, dev, "WAKE&NETTX: "
270 			 "skb %p sending %d bytes to radio\n",
271 			 skb, skb->len);
272 		d_dump(4, dev, skb->data, skb->len);
273 	}
274 	/* We hold a ref count for i2400m and skb, so when
275 	 * stopping() the device, we need to cancel that work
276 	 * and if pending, release those resources. */
277 	result = 0;
278 	spin_lock_irqsave(&i2400m->tx_lock, flags);
279 	if (!i2400m->wake_tx_skb) {
280 		netif_stop_queue(net_dev);
281 		i2400m_get(i2400m);
282 		i2400m->wake_tx_skb = skb_get(skb);	/* transfer ref count */
283 		i2400m_tx_prep_header(skb);
284 		result = schedule_work(&i2400m->wake_tx_ws);
285 		WARN_ON(result == 0);
286 	}
287 	spin_unlock_irqrestore(&i2400m->tx_lock, flags);
288 	if (result == 0) {
289 		/* Yes, this happens even if we stopped the
290 		 * queue -- blame the queue disciplines that
291 		 * queue without looking -- I guess there is a reason
292 		 * for that. */
293 		if (net_ratelimit())
294 			d_printf(1, dev, "NETTX: device exiting idle, "
295 				 "dropping skb %p, queue running %d\n",
296 				 skb, netif_queue_stopped(net_dev));
297 		result = -EBUSY;
298 	}
299 	d_fnend(3, dev, "(skb %p net_dev %p) = %d\n", skb, net_dev, result);
300 	return result;
301 }
302 
303 
304 /*
305  * Transmit a packet to the base station on behalf of the network stack.
306  *
307  * Returns: 0 if ok, < 0 errno code on error.
308  *
309  * We need to pull the ethernet header and add the hardware header,
310  * which is currently set to all zeroes and reserved.
311  */
312 static
i2400m_net_tx(struct i2400m * i2400m,struct net_device * net_dev,struct sk_buff * skb)313 int i2400m_net_tx(struct i2400m *i2400m, struct net_device *net_dev,
314 		  struct sk_buff *skb)
315 {
316 	int result;
317 	struct device *dev = i2400m_dev(i2400m);
318 
319 	d_fnstart(3, dev, "(i2400m %p net_dev %p skb %p)\n",
320 		  i2400m, net_dev, skb);
321 	/* FIXME: check eth hdr, only IPv4 is routed by the device as of now */
322 	netif_trans_update(net_dev);
323 	i2400m_tx_prep_header(skb);
324 	d_printf(3, dev, "NETTX: skb %p sending %d bytes to radio\n",
325 		 skb, skb->len);
326 	d_dump(4, dev, skb->data, skb->len);
327 	result = i2400m_tx(i2400m, skb->data, skb->len, I2400M_PT_DATA);
328 	d_fnend(3, dev, "(i2400m %p net_dev %p skb %p) = %d\n",
329 		i2400m, net_dev, skb, result);
330 	return result;
331 }
332 
333 
334 /*
335  * Transmit a packet to the base station on behalf of the network stack
336  *
337  *
338  * Returns: NETDEV_TX_OK (always, even in case of error)
339  *
340  * In case of error, we just drop it. Reasons:
341  *
342  *  - we add a hw header to each skb, and if the network stack
343  *    retries, we have no way to know if that skb has it or not.
344  *
345  *  - network protocols have their own drop-recovery mechanisms
346  *
347  *  - there is not much else we can do
348  *
349  * If the device is idle, we need to wake it up; that is an operation
350  * that will sleep. See i2400m_net_wake_tx() for details.
351  */
352 static
i2400m_hard_start_xmit(struct sk_buff * skb,struct net_device * net_dev)353 netdev_tx_t i2400m_hard_start_xmit(struct sk_buff *skb,
354 					 struct net_device *net_dev)
355 {
356 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
357 	struct device *dev = i2400m_dev(i2400m);
358 	int result = -1;
359 
360 	d_fnstart(3, dev, "(skb %p net_dev %p)\n", skb, net_dev);
361 
362 	if (skb_cow_head(skb, 0))
363 		goto drop;
364 
365 	if (i2400m->state == I2400M_SS_IDLE)
366 		result = i2400m_net_wake_tx(i2400m, net_dev, skb);
367 	else
368 		result = i2400m_net_tx(i2400m, net_dev, skb);
369 	if (result <  0) {
370 drop:
371 		net_dev->stats.tx_dropped++;
372 	} else {
373 		net_dev->stats.tx_packets++;
374 		net_dev->stats.tx_bytes += skb->len;
375 	}
376 	dev_kfree_skb(skb);
377 	d_fnend(3, dev, "(skb %p net_dev %p) = %d\n", skb, net_dev, result);
378 	return NETDEV_TX_OK;
379 }
380 
381 
382 static
i2400m_tx_timeout(struct net_device * net_dev,unsigned int txqueue)383 void i2400m_tx_timeout(struct net_device *net_dev, unsigned int txqueue)
384 {
385 	/*
386 	 * We might want to kick the device
387 	 *
388 	 * There is not much we can do though, as the device requires
389 	 * that we send the data aggregated. By the time we receive
390 	 * this, there might be data pending to be sent or not...
391 	 */
392 	net_dev->stats.tx_errors++;
393 }
394 
395 
396 /*
397  * Create a fake ethernet header
398  *
399  * For emulating an ethernet device, every received IP header has to
400  * be prefixed with an ethernet header. Fake it with the given
401  * protocol.
402  */
403 static
i2400m_rx_fake_eth_header(struct net_device * net_dev,void * _eth_hdr,__be16 protocol)404 void i2400m_rx_fake_eth_header(struct net_device *net_dev,
405 			       void *_eth_hdr, __be16 protocol)
406 {
407 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
408 	struct ethhdr *eth_hdr = _eth_hdr;
409 
410 	memcpy(eth_hdr->h_dest, net_dev->dev_addr, sizeof(eth_hdr->h_dest));
411 	memcpy(eth_hdr->h_source, i2400m->src_mac_addr,
412 	       sizeof(eth_hdr->h_source));
413 	eth_hdr->h_proto = protocol;
414 }
415 
416 
417 /*
418  * i2400m_net_rx - pass a network packet to the stack
419  *
420  * @i2400m: device instance
421  * @skb_rx: the skb where the buffer pointed to by @buf is
422  * @i: 1 if payload is the only one
423  * @buf: pointer to the buffer containing the data
424  * @len: buffer's length
425  *
426  * This is only used now for the v1.3 firmware. It will be deprecated
427  * in >= 2.6.31.
428  *
429  * Note that due to firmware limitations, we don't have space to add
430  * an ethernet header, so we need to copy each packet. Firmware
431  * versions >= v1.4 fix this [see i2400m_net_erx()].
432  *
433  * We just clone the skb and set it up so that it's skb->data pointer
434  * points to "buf" and it's length.
435  *
436  * Note that if the payload is the last (or the only one) in a
437  * multi-payload message, we don't clone the SKB but just reuse it.
438  *
439  * This function is normally run from a thread context. However, we
440  * still use netif_rx() instead of netif_receive_skb() as was
441  * recommended in the mailing list. Reason is in some stress tests
442  * when sending/receiving a lot of data we seem to hit a softlock in
443  * the kernel's TCP implementation [aroudn tcp_delay_timer()]. Using
444  * netif_rx() took care of the issue.
445  *
446  * This is, of course, still open to do more research on why running
447  * with netif_receive_skb() hits this softlock. FIXME.
448  *
449  * FIXME: currently we don't do any efforts at distinguishing if what
450  * we got was an IPv4 or IPv6 header, to setup the protocol field
451  * correctly.
452  */
i2400m_net_rx(struct i2400m * i2400m,struct sk_buff * skb_rx,unsigned i,const void * buf,int buf_len)453 void i2400m_net_rx(struct i2400m *i2400m, struct sk_buff *skb_rx,
454 		   unsigned i, const void *buf, int buf_len)
455 {
456 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
457 	struct device *dev = i2400m_dev(i2400m);
458 	struct sk_buff *skb;
459 
460 	d_fnstart(2, dev, "(i2400m %p buf %p buf_len %d)\n",
461 		  i2400m, buf, buf_len);
462 	if (i) {
463 		skb = skb_get(skb_rx);
464 		d_printf(2, dev, "RX: reusing first payload skb %p\n", skb);
465 		skb_pull(skb, buf - (void *) skb->data);
466 		skb_trim(skb, (void *) skb_end_pointer(skb) - buf);
467 	} else {
468 		/* Yes, this is bad -- a lot of overhead -- see
469 		 * comments at the top of the file */
470 		skb = __netdev_alloc_skb(net_dev, buf_len, GFP_KERNEL);
471 		if (skb == NULL) {
472 			dev_err(dev, "NETRX: no memory to realloc skb\n");
473 			net_dev->stats.rx_dropped++;
474 			goto error_skb_realloc;
475 		}
476 		skb_put_data(skb, buf, buf_len);
477 	}
478 	i2400m_rx_fake_eth_header(i2400m->wimax_dev.net_dev,
479 				  skb->data - ETH_HLEN,
480 				  cpu_to_be16(ETH_P_IP));
481 	skb_set_mac_header(skb, -ETH_HLEN);
482 	skb->dev = i2400m->wimax_dev.net_dev;
483 	skb->protocol = htons(ETH_P_IP);
484 	net_dev->stats.rx_packets++;
485 	net_dev->stats.rx_bytes += buf_len;
486 	d_printf(3, dev, "NETRX: receiving %d bytes to network stack\n",
487 		buf_len);
488 	d_dump(4, dev, buf, buf_len);
489 	netif_rx_ni(skb);	/* see notes in function header */
490 error_skb_realloc:
491 	d_fnend(2, dev, "(i2400m %p buf %p buf_len %d) = void\n",
492 		i2400m, buf, buf_len);
493 }
494 
495 
496 /*
497  * i2400m_net_erx - pass a network packet to the stack (extended version)
498  *
499  * @i2400m: device descriptor
500  * @skb: the skb where the packet is - the skb should be set to point
501  *     at the IP packet; this function will add ethernet headers if
502  *     needed.
503  * @cs: packet type
504  *
505  * This is only used now for firmware >= v1.4. Note it is quite
506  * similar to i2400m_net_rx() (used only for v1.3 firmware).
507  *
508  * This function is normally run from a thread context. However, we
509  * still use netif_rx() instead of netif_receive_skb() as was
510  * recommended in the mailing list. Reason is in some stress tests
511  * when sending/receiving a lot of data we seem to hit a softlock in
512  * the kernel's TCP implementation [aroudn tcp_delay_timer()]. Using
513  * netif_rx() took care of the issue.
514  *
515  * This is, of course, still open to do more research on why running
516  * with netif_receive_skb() hits this softlock. FIXME.
517  */
i2400m_net_erx(struct i2400m * i2400m,struct sk_buff * skb,enum i2400m_cs cs)518 void i2400m_net_erx(struct i2400m *i2400m, struct sk_buff *skb,
519 		    enum i2400m_cs cs)
520 {
521 	struct net_device *net_dev = i2400m->wimax_dev.net_dev;
522 	struct device *dev = i2400m_dev(i2400m);
523 
524 	d_fnstart(2, dev, "(i2400m %p skb %p [%u] cs %d)\n",
525 		  i2400m, skb, skb->len, cs);
526 	switch(cs) {
527 	case I2400M_CS_IPV4_0:
528 	case I2400M_CS_IPV4:
529 		i2400m_rx_fake_eth_header(i2400m->wimax_dev.net_dev,
530 					  skb->data - ETH_HLEN,
531 					  cpu_to_be16(ETH_P_IP));
532 		skb_set_mac_header(skb, -ETH_HLEN);
533 		skb->dev = i2400m->wimax_dev.net_dev;
534 		skb->protocol = htons(ETH_P_IP);
535 		net_dev->stats.rx_packets++;
536 		net_dev->stats.rx_bytes += skb->len;
537 		break;
538 	default:
539 		dev_err(dev, "ERX: BUG? CS type %u unsupported\n", cs);
540 		goto error;
541 
542 	}
543 	d_printf(3, dev, "ERX: receiving %d bytes to the network stack\n",
544 		 skb->len);
545 	d_dump(4, dev, skb->data, skb->len);
546 	netif_rx_ni(skb);	/* see notes in function header */
547 error:
548 	d_fnend(2, dev, "(i2400m %p skb %p [%u] cs %d) = void\n",
549 		i2400m, skb, skb->len, cs);
550 }
551 
552 static const struct net_device_ops i2400m_netdev_ops = {
553 	.ndo_open = i2400m_open,
554 	.ndo_stop = i2400m_stop,
555 	.ndo_start_xmit = i2400m_hard_start_xmit,
556 	.ndo_tx_timeout = i2400m_tx_timeout,
557 };
558 
i2400m_get_drvinfo(struct net_device * net_dev,struct ethtool_drvinfo * info)559 static void i2400m_get_drvinfo(struct net_device *net_dev,
560 			       struct ethtool_drvinfo *info)
561 {
562 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
563 
564 	strlcpy(info->driver, KBUILD_MODNAME, sizeof(info->driver));
565 	strlcpy(info->fw_version, i2400m->fw_name ? : "",
566 		sizeof(info->fw_version));
567 	if (net_dev->dev.parent)
568 		strlcpy(info->bus_info, dev_name(net_dev->dev.parent),
569 			sizeof(info->bus_info));
570 }
571 
572 static const struct ethtool_ops i2400m_ethtool_ops = {
573 	.get_drvinfo = i2400m_get_drvinfo,
574 	.get_link = ethtool_op_get_link,
575 };
576 
577 /**
578  * i2400m_netdev_setup - Setup setup @net_dev's i2400m private data
579  *
580  * Called by alloc_netdev()
581  */
i2400m_netdev_setup(struct net_device * net_dev)582 void i2400m_netdev_setup(struct net_device *net_dev)
583 {
584 	d_fnstart(3, NULL, "(net_dev %p)\n", net_dev);
585 	ether_setup(net_dev);
586 	net_dev->mtu = I2400M_MAX_MTU;
587 	net_dev->min_mtu = 0;
588 	net_dev->max_mtu = I2400M_MAX_MTU;
589 	net_dev->tx_queue_len = I2400M_TX_QLEN;
590 	net_dev->features =
591 		  NETIF_F_VLAN_CHALLENGED
592 		| NETIF_F_HIGHDMA;
593 	net_dev->flags =
594 		IFF_NOARP		/* i2400m is apure IP device */
595 		& (~IFF_BROADCAST	/* i2400m is P2P */
596 		   & ~IFF_MULTICAST);
597 	net_dev->watchdog_timeo = I2400M_TX_TIMEOUT;
598 	net_dev->netdev_ops = &i2400m_netdev_ops;
599 	net_dev->ethtool_ops = &i2400m_ethtool_ops;
600 	d_fnend(3, NULL, "(net_dev %p) = void\n", net_dev);
601 }
602 EXPORT_SYMBOL_GPL(i2400m_netdev_setup);
603 
604