xref: /linux/drivers/net/usb/sierra_net.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * USB-to-WWAN Driver for Sierra Wireless modems
4  *
5  * Copyright (C) 2008, 2009, 2010 Paxton Smith, Matthew Safar, Rory Filer
6  *                          <linux@sierrawireless.com>
7  *
8  * Portions of this based on the cdc_ether driver by David Brownell (2003-2005)
9  * and Ole Andre Vadla Ravnas (ActiveSync) (2006).
10  *
11  * IMPORTANT DISCLAIMER: This driver is not commercially supported by
12  * Sierra Wireless. Use at your own risk.
13  */
14 
15 #define DRIVER_VERSION "v.2.0"
16 #define DRIVER_AUTHOR "Paxton Smith, Matthew Safar, Rory Filer"
17 #define DRIVER_DESC "USB-to-WWAN Driver for Sierra Wireless modems"
18 static const char driver_name[] = "sierra_net";
19 
20 /* if defined debug messages enabled */
21 /*#define	DEBUG*/
22 
23 #include <linux/module.h>
24 #include <linux/etherdevice.h>
25 #include <linux/ethtool.h>
26 #include <linux/mii.h>
27 #include <linux/sched.h>
28 #include <linux/timer.h>
29 #include <linux/usb.h>
30 #include <linux/usb/cdc.h>
31 #include <net/ip.h>
32 #include <net/udp.h>
33 #include <asm/unaligned.h>
34 #include <linux/usb/usbnet.h>
35 
36 #define SWI_USB_REQUEST_GET_FW_ATTR	0x06
37 #define SWI_GET_FW_ATTR_MASK		0x08
38 
39 /* atomic counter partially included in MAC address to make sure 2 devices
40  * do not end up with the same MAC - concept breaks in case of > 255 ifaces
41  */
42 static	atomic_t iface_counter = ATOMIC_INIT(0);
43 
44 /*
45  * SYNC Timer Delay definition used to set the expiry time
46  */
47 #define SIERRA_NET_SYNCDELAY (2*HZ)
48 
49 /* Max. MTU supported. The modem buffers are limited to 1500 */
50 #define SIERRA_NET_MAX_SUPPORTED_MTU	1500
51 
52 /* The SIERRA_NET_USBCTL_BUF_LEN defines a buffer size allocated for control
53  * message reception ... and thus the max. received packet.
54  * (May be the cause for parse_hip returning -EINVAL)
55  */
56 #define SIERRA_NET_USBCTL_BUF_LEN	1024
57 
58 /* Overriding the default usbnet rx_urb_size */
59 #define SIERRA_NET_RX_URB_SIZE		(8 * 1024)
60 
61 /* Private data structure */
62 struct sierra_net_data {
63 
64 	u16 link_up;		/* air link up or down */
65 	u8 tx_hdr_template[4];	/* part of HIP hdr for tx'd packets */
66 
67 	u8 sync_msg[4];		/* SYNC message */
68 	u8 shdwn_msg[4];	/* Shutdown message */
69 
70 	/* Backpointer to the container */
71 	struct usbnet *usbnet;
72 
73 	u8 ifnum;	/* interface number */
74 
75 /* Bit masks, must be a power of 2 */
76 #define SIERRA_NET_EVENT_RESP_AVAIL    0x01
77 #define SIERRA_NET_TIMER_EXPIRY        0x02
78 	unsigned long kevent_flags;
79 	struct work_struct sierra_net_kevent;
80 	struct timer_list sync_timer; /* For retrying SYNC sequence */
81 };
82 
83 struct param {
84 	int is_present;
85 	union {
86 		void  *ptr;
87 		u32    dword;
88 		u16    word;
89 		u8     byte;
90 	};
91 };
92 
93 /* HIP message type */
94 #define SIERRA_NET_HIP_EXTENDEDID	0x7F
95 #define SIERRA_NET_HIP_HSYNC_ID		0x60	/* Modem -> host */
96 #define SIERRA_NET_HIP_RESTART_ID	0x62	/* Modem -> host */
97 #define SIERRA_NET_HIP_MSYNC_ID		0x20	/* Host -> modem */
98 #define SIERRA_NET_HIP_SHUTD_ID		0x26	/* Host -> modem */
99 
100 #define SIERRA_NET_HIP_EXT_IP_IN_ID   0x0202
101 #define SIERRA_NET_HIP_EXT_IP_OUT_ID  0x0002
102 
103 /* 3G UMTS Link Sense Indication definitions */
104 #define SIERRA_NET_HIP_LSI_UMTSID	0x78
105 
106 /* Reverse Channel Grant Indication HIP message */
107 #define SIERRA_NET_HIP_RCGI		0x64
108 
109 /* LSI Protocol types */
110 #define SIERRA_NET_PROTOCOL_UMTS      0x01
111 #define SIERRA_NET_PROTOCOL_UMTS_DS   0x04
112 /* LSI Coverage */
113 #define SIERRA_NET_COVERAGE_NONE      0x00
114 #define SIERRA_NET_COVERAGE_NOPACKET  0x01
115 
116 /* LSI Session */
117 #define SIERRA_NET_SESSION_IDLE       0x00
118 /* LSI Link types */
119 #define SIERRA_NET_AS_LINK_TYPE_IPV4  0x00
120 #define SIERRA_NET_AS_LINK_TYPE_IPV6  0x02
121 
122 struct lsi_umts {
123 	u8 protocol;
124 	u8 unused1;
125 	__be16 length;
126 	/* eventually use a union for the rest - assume umts for now */
127 	u8 coverage;
128 	u8 network_len; /* network name len */
129 	u8 network[40]; /* network name (UCS2, bigendian) */
130 	u8 session_state;
131 	u8 unused3[33];
132 } __packed;
133 
134 struct lsi_umts_single {
135 	struct lsi_umts lsi;
136 	u8 link_type;
137 	u8 pdp_addr_len; /* NW-supplied PDP address len */
138 	u8 pdp_addr[16]; /* NW-supplied PDP address (bigendian)) */
139 	u8 unused4[23];
140 	u8 dns1_addr_len; /* NW-supplied 1st DNS address len (bigendian) */
141 	u8 dns1_addr[16]; /* NW-supplied 1st DNS address */
142 	u8 dns2_addr_len; /* NW-supplied 2nd DNS address len */
143 	u8 dns2_addr[16]; /* NW-supplied 2nd DNS address (bigendian)*/
144 	u8 wins1_addr_len; /* NW-supplied 1st Wins address len */
145 	u8 wins1_addr[16]; /* NW-supplied 1st Wins address (bigendian)*/
146 	u8 wins2_addr_len; /* NW-supplied 2nd Wins address len */
147 	u8 wins2_addr[16]; /* NW-supplied 2nd Wins address (bigendian) */
148 	u8 unused5[4];
149 	u8 gw_addr_len; /* NW-supplied GW address len */
150 	u8 gw_addr[16]; /* NW-supplied GW address (bigendian) */
151 	u8 reserved[8];
152 } __packed;
153 
154 struct lsi_umts_dual {
155 	struct lsi_umts lsi;
156 	u8 pdp_addr4_len; /* NW-supplied PDP IPv4 address len */
157 	u8 pdp_addr4[4];  /* NW-supplied PDP IPv4 address (bigendian)) */
158 	u8 pdp_addr6_len; /* NW-supplied PDP IPv6 address len */
159 	u8 pdp_addr6[16]; /* NW-supplied PDP IPv6 address (bigendian)) */
160 	u8 unused4[23];
161 	u8 dns1_addr4_len; /* NW-supplied 1st DNS v4 address len (bigendian) */
162 	u8 dns1_addr4[4];  /* NW-supplied 1st DNS v4 address */
163 	u8 dns1_addr6_len; /* NW-supplied 1st DNS v6 address len */
164 	u8 dns1_addr6[16]; /* NW-supplied 1st DNS v6 address (bigendian)*/
165 	u8 dns2_addr4_len; /* NW-supplied 2nd DNS v4 address len (bigendian) */
166 	u8 dns2_addr4[4];  /* NW-supplied 2nd DNS v4 address */
167 	u8 dns2_addr6_len; /* NW-supplied 2nd DNS v6 address len */
168 	u8 dns2_addr6[16]; /* NW-supplied 2nd DNS v6 address (bigendian)*/
169 	u8 unused5[68];
170 } __packed;
171 
172 #define SIERRA_NET_LSI_COMMON_LEN      4
173 #define SIERRA_NET_LSI_UMTS_LEN        (sizeof(struct lsi_umts_single))
174 #define SIERRA_NET_LSI_UMTS_STATUS_LEN \
175 	(SIERRA_NET_LSI_UMTS_LEN - SIERRA_NET_LSI_COMMON_LEN)
176 #define SIERRA_NET_LSI_UMTS_DS_LEN     (sizeof(struct lsi_umts_dual))
177 #define SIERRA_NET_LSI_UMTS_DS_STATUS_LEN \
178 	(SIERRA_NET_LSI_UMTS_DS_LEN - SIERRA_NET_LSI_COMMON_LEN)
179 
180 /* Our own net device operations structure */
181 static const struct net_device_ops sierra_net_device_ops = {
182 	.ndo_open               = usbnet_open,
183 	.ndo_stop               = usbnet_stop,
184 	.ndo_start_xmit         = usbnet_start_xmit,
185 	.ndo_tx_timeout         = usbnet_tx_timeout,
186 	.ndo_change_mtu         = usbnet_change_mtu,
187 	.ndo_get_stats64        = dev_get_tstats64,
188 	.ndo_set_mac_address    = eth_mac_addr,
189 	.ndo_validate_addr      = eth_validate_addr,
190 };
191 
192 /* get private data associated with passed in usbnet device */
193 static inline struct sierra_net_data *sierra_net_get_private(struct usbnet *dev)
194 {
195 	return (struct sierra_net_data *)dev->data[0];
196 }
197 
198 /* set private data associated with passed in usbnet device */
199 static inline void sierra_net_set_private(struct usbnet *dev,
200 			struct sierra_net_data *priv)
201 {
202 	dev->data[0] = (unsigned long)priv;
203 }
204 
205 /* is packet IPv4/IPv6 */
206 static inline int is_ip(struct sk_buff *skb)
207 {
208 	return skb->protocol == cpu_to_be16(ETH_P_IP) ||
209 	       skb->protocol == cpu_to_be16(ETH_P_IPV6);
210 }
211 
212 /*
213  * check passed in packet and make sure that:
214  *  - it is linear (no scatter/gather)
215  *  - it is ethernet (mac_header properly set)
216  */
217 static int check_ethip_packet(struct sk_buff *skb, struct usbnet *dev)
218 {
219 	skb_reset_mac_header(skb); /* ethernet header */
220 
221 	if (skb_is_nonlinear(skb)) {
222 		netdev_err(dev->net, "Non linear buffer-dropping\n");
223 		return 0;
224 	}
225 
226 	if (!pskb_may_pull(skb, ETH_HLEN))
227 		return 0;
228 	skb->protocol = eth_hdr(skb)->h_proto;
229 
230 	return 1;
231 }
232 
233 static const u8 *save16bit(struct param *p, const u8 *datap)
234 {
235 	p->is_present = 1;
236 	p->word = get_unaligned_be16(datap);
237 	return datap + sizeof(p->word);
238 }
239 
240 static const u8 *save8bit(struct param *p, const u8 *datap)
241 {
242 	p->is_present = 1;
243 	p->byte = *datap;
244 	return datap + sizeof(p->byte);
245 }
246 
247 /*----------------------------------------------------------------------------*
248  *                              BEGIN HIP                                     *
249  *----------------------------------------------------------------------------*/
250 /* HIP header */
251 #define SIERRA_NET_HIP_HDR_LEN 4
252 /* Extended HIP header */
253 #define SIERRA_NET_HIP_EXT_HDR_LEN 6
254 
255 struct hip_hdr {
256 	int    hdrlen;
257 	struct param payload_len;
258 	struct param msgid;
259 	struct param msgspecific;
260 	struct param extmsgid;
261 };
262 
263 static int parse_hip(const u8 *buf, const u32 buflen, struct hip_hdr *hh)
264 {
265 	const u8 *curp = buf;
266 	int    padded;
267 
268 	if (buflen < SIERRA_NET_HIP_HDR_LEN)
269 		return -EPROTO;
270 
271 	curp = save16bit(&hh->payload_len, curp);
272 	curp = save8bit(&hh->msgid, curp);
273 	curp = save8bit(&hh->msgspecific, curp);
274 
275 	padded = hh->msgid.byte & 0x80;
276 	hh->msgid.byte &= 0x7F;			/* 7 bits */
277 
278 	hh->extmsgid.is_present = (hh->msgid.byte == SIERRA_NET_HIP_EXTENDEDID);
279 	if (hh->extmsgid.is_present) {
280 		if (buflen < SIERRA_NET_HIP_EXT_HDR_LEN)
281 			return -EPROTO;
282 
283 		hh->payload_len.word &= 0x3FFF; /* 14 bits */
284 
285 		curp = save16bit(&hh->extmsgid, curp);
286 		hh->extmsgid.word &= 0x03FF;	/* 10 bits */
287 
288 		hh->hdrlen = SIERRA_NET_HIP_EXT_HDR_LEN;
289 	} else {
290 		hh->payload_len.word &= 0x07FF;	/* 11 bits */
291 		hh->hdrlen = SIERRA_NET_HIP_HDR_LEN;
292 	}
293 
294 	if (padded) {
295 		hh->hdrlen++;
296 		hh->payload_len.word--;
297 	}
298 
299 	/* if real packet shorter than the claimed length */
300 	if (buflen < (hh->hdrlen + hh->payload_len.word))
301 		return -EINVAL;
302 
303 	return 0;
304 }
305 
306 static void build_hip(u8 *buf, const u16 payloadlen,
307 		struct sierra_net_data *priv)
308 {
309 	/* the following doesn't have the full functionality. We
310 	 * currently build only one kind of header, so it is faster this way
311 	 */
312 	put_unaligned_be16(payloadlen, buf);
313 	memcpy(buf+2, priv->tx_hdr_template, sizeof(priv->tx_hdr_template));
314 }
315 /*----------------------------------------------------------------------------*
316  *                              END HIP                                       *
317  *----------------------------------------------------------------------------*/
318 
319 static int sierra_net_send_cmd(struct usbnet *dev,
320 		u8 *cmd, int cmdlen, const char * cmd_name)
321 {
322 	struct sierra_net_data *priv = sierra_net_get_private(dev);
323 	int  status;
324 
325 	status = usbnet_write_cmd(dev, USB_CDC_SEND_ENCAPSULATED_COMMAND,
326 				  USB_DIR_OUT|USB_TYPE_CLASS|USB_RECIP_INTERFACE,
327 				  0, priv->ifnum, cmd, cmdlen);
328 
329 	if (status != cmdlen && status != -ENODEV)
330 		netdev_err(dev->net, "Submit %s failed %d\n", cmd_name, status);
331 
332 	return status;
333 }
334 
335 static int sierra_net_send_sync(struct usbnet *dev)
336 {
337 	int  status;
338 	struct sierra_net_data *priv = sierra_net_get_private(dev);
339 
340 	dev_dbg(&dev->udev->dev, "%s", __func__);
341 
342 	status = sierra_net_send_cmd(dev, priv->sync_msg,
343 			sizeof(priv->sync_msg), "SYNC");
344 
345 	return status;
346 }
347 
348 static void sierra_net_set_ctx_index(struct sierra_net_data *priv, u8 ctx_ix)
349 {
350 	dev_dbg(&(priv->usbnet->udev->dev), "%s %d", __func__, ctx_ix);
351 	priv->tx_hdr_template[0] = 0x3F;
352 	priv->tx_hdr_template[1] = ctx_ix;
353 	*((__be16 *)&priv->tx_hdr_template[2]) =
354 		cpu_to_be16(SIERRA_NET_HIP_EXT_IP_OUT_ID);
355 }
356 
357 static int sierra_net_parse_lsi(struct usbnet *dev, char *data, int datalen)
358 {
359 	struct lsi_umts *lsi = (struct lsi_umts *)data;
360 	u32 expected_length;
361 
362 	if (datalen < sizeof(struct lsi_umts_single)) {
363 		netdev_err(dev->net, "%s: Data length %d, exp >= %zu\n",
364 			   __func__, datalen, sizeof(struct lsi_umts_single));
365 		return -1;
366 	}
367 
368 	/* Validate the session state */
369 	if (lsi->session_state == SIERRA_NET_SESSION_IDLE) {
370 		netdev_err(dev->net, "Session idle, 0x%02x\n",
371 			   lsi->session_state);
372 		return 0;
373 	}
374 
375 	/* Validate the protocol  - only support UMTS for now */
376 	if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS) {
377 		struct lsi_umts_single *single = (struct lsi_umts_single *)lsi;
378 
379 		/* Validate the link type */
380 		if (single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV4 &&
381 		    single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV6) {
382 			netdev_err(dev->net, "Link type unsupported: 0x%02x\n",
383 				   single->link_type);
384 			return -1;
385 		}
386 		expected_length = SIERRA_NET_LSI_UMTS_STATUS_LEN;
387 	} else if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS_DS) {
388 		expected_length = SIERRA_NET_LSI_UMTS_DS_STATUS_LEN;
389 	} else {
390 		netdev_err(dev->net, "Protocol unsupported, 0x%02x\n",
391 			   lsi->protocol);
392 		return -1;
393 	}
394 
395 	if (be16_to_cpu(lsi->length) != expected_length) {
396 		netdev_err(dev->net, "%s: LSI_UMTS_STATUS_LEN %d, exp %u\n",
397 			   __func__, be16_to_cpu(lsi->length), expected_length);
398 		return -1;
399 	}
400 
401 	/* Validate the coverage */
402 	if (lsi->coverage == SIERRA_NET_COVERAGE_NONE ||
403 	    lsi->coverage == SIERRA_NET_COVERAGE_NOPACKET) {
404 		netdev_err(dev->net, "No coverage, 0x%02x\n", lsi->coverage);
405 		return 0;
406 	}
407 
408 	/* Set link_sense true */
409 	return 1;
410 }
411 
412 static void sierra_net_handle_lsi(struct usbnet *dev, char *data,
413 		struct hip_hdr	*hh)
414 {
415 	struct sierra_net_data *priv = sierra_net_get_private(dev);
416 	int link_up;
417 
418 	link_up = sierra_net_parse_lsi(dev, data + hh->hdrlen,
419 					hh->payload_len.word);
420 	if (link_up < 0) {
421 		netdev_err(dev->net, "Invalid LSI\n");
422 		return;
423 	}
424 	if (link_up) {
425 		sierra_net_set_ctx_index(priv, hh->msgspecific.byte);
426 		priv->link_up = 1;
427 	} else {
428 		priv->link_up = 0;
429 	}
430 	usbnet_link_change(dev, link_up, 0);
431 }
432 
433 static void sierra_net_dosync(struct usbnet *dev)
434 {
435 	int status;
436 	struct sierra_net_data *priv = sierra_net_get_private(dev);
437 
438 	dev_dbg(&dev->udev->dev, "%s", __func__);
439 
440 	/* The SIERRA_NET_HIP_MSYNC_ID command appears to request that the
441 	 * firmware restart itself.  After restarting, the modem will respond
442 	 * with the SIERRA_NET_HIP_RESTART_ID indication.  The driver continues
443 	 * sending MSYNC commands every few seconds until it receives the
444 	 * RESTART event from the firmware
445 	 */
446 
447 	/* tell modem we are ready */
448 	status = sierra_net_send_sync(dev);
449 	if (status < 0)
450 		netdev_err(dev->net,
451 			"Send SYNC failed, status %d\n", status);
452 	status = sierra_net_send_sync(dev);
453 	if (status < 0)
454 		netdev_err(dev->net,
455 			"Send SYNC failed, status %d\n", status);
456 
457 	/* Now, start a timer and make sure we get the Restart Indication */
458 	priv->sync_timer.expires = jiffies + SIERRA_NET_SYNCDELAY;
459 	add_timer(&priv->sync_timer);
460 }
461 
462 static void sierra_net_kevent(struct work_struct *work)
463 {
464 	struct sierra_net_data *priv =
465 		container_of(work, struct sierra_net_data, sierra_net_kevent);
466 	struct usbnet *dev = priv->usbnet;
467 	int  len;
468 	int  err;
469 	u8  *buf;
470 	u8   ifnum;
471 
472 	if (test_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags)) {
473 		clear_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags);
474 
475 		/* Query the modem for the LSI message */
476 		buf = kzalloc(SIERRA_NET_USBCTL_BUF_LEN, GFP_KERNEL);
477 		if (!buf)
478 			return;
479 
480 		ifnum = priv->ifnum;
481 		len = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
482 				USB_CDC_GET_ENCAPSULATED_RESPONSE,
483 				USB_DIR_IN|USB_TYPE_CLASS|USB_RECIP_INTERFACE,
484 				0, ifnum, buf, SIERRA_NET_USBCTL_BUF_LEN,
485 				USB_CTRL_SET_TIMEOUT);
486 
487 		if (len < 0) {
488 			netdev_err(dev->net,
489 				"usb_control_msg failed, status %d\n", len);
490 		} else {
491 			struct hip_hdr	hh;
492 
493 			dev_dbg(&dev->udev->dev, "%s: Received status message,"
494 				" %04x bytes", __func__, len);
495 
496 			err = parse_hip(buf, len, &hh);
497 			if (err) {
498 				netdev_err(dev->net, "%s: Bad packet,"
499 					" parse result %d\n", __func__, err);
500 				kfree(buf);
501 				return;
502 			}
503 
504 			/* Validate packet length */
505 			if (len != hh.hdrlen + hh.payload_len.word) {
506 				netdev_err(dev->net, "%s: Bad packet, received"
507 					" %d, expected %d\n",	__func__, len,
508 					hh.hdrlen + hh.payload_len.word);
509 				kfree(buf);
510 				return;
511 			}
512 
513 			/* Switch on received message types */
514 			switch (hh.msgid.byte) {
515 			case SIERRA_NET_HIP_LSI_UMTSID:
516 				dev_dbg(&dev->udev->dev, "LSI for ctx:%d",
517 					hh.msgspecific.byte);
518 				sierra_net_handle_lsi(dev, buf, &hh);
519 				break;
520 			case SIERRA_NET_HIP_RESTART_ID:
521 				dev_dbg(&dev->udev->dev, "Restart reported: %d,"
522 						" stopping sync timer",
523 						hh.msgspecific.byte);
524 				/* Got sync resp - stop timer & clear mask */
525 				del_timer_sync(&priv->sync_timer);
526 				clear_bit(SIERRA_NET_TIMER_EXPIRY,
527 					  &priv->kevent_flags);
528 				break;
529 			case SIERRA_NET_HIP_HSYNC_ID:
530 				dev_dbg(&dev->udev->dev, "SYNC received");
531 				err = sierra_net_send_sync(dev);
532 				if (err < 0)
533 					netdev_err(dev->net,
534 						"Send SYNC failed %d\n", err);
535 				break;
536 			case SIERRA_NET_HIP_EXTENDEDID:
537 				netdev_err(dev->net, "Unrecognized HIP msg, "
538 					"extmsgid 0x%04x\n", hh.extmsgid.word);
539 				break;
540 			case SIERRA_NET_HIP_RCGI:
541 				/* Ignored */
542 				break;
543 			default:
544 				netdev_err(dev->net, "Unrecognized HIP msg, "
545 					"msgid 0x%02x\n", hh.msgid.byte);
546 				break;
547 			}
548 		}
549 		kfree(buf);
550 	}
551 	/* The sync timer bit might be set */
552 	if (test_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags)) {
553 		clear_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags);
554 		dev_dbg(&dev->udev->dev, "Deferred sync timer expiry");
555 		sierra_net_dosync(priv->usbnet);
556 	}
557 
558 	if (priv->kevent_flags)
559 		dev_dbg(&dev->udev->dev, "sierra_net_kevent done, "
560 			"kevent_flags = 0x%lx", priv->kevent_flags);
561 }
562 
563 static void sierra_net_defer_kevent(struct usbnet *dev, int work)
564 {
565 	struct sierra_net_data *priv = sierra_net_get_private(dev);
566 
567 	set_bit(work, &priv->kevent_flags);
568 	schedule_work(&priv->sierra_net_kevent);
569 }
570 
571 /*
572  * Sync Retransmit Timer Handler. On expiry, kick the work queue
573  */
574 static void sierra_sync_timer(struct timer_list *t)
575 {
576 	struct sierra_net_data *priv = from_timer(priv, t, sync_timer);
577 	struct usbnet *dev = priv->usbnet;
578 
579 	dev_dbg(&dev->udev->dev, "%s", __func__);
580 	/* Kick the tasklet */
581 	sierra_net_defer_kevent(dev, SIERRA_NET_TIMER_EXPIRY);
582 }
583 
584 static void sierra_net_status(struct usbnet *dev, struct urb *urb)
585 {
586 	struct usb_cdc_notification *event;
587 
588 	dev_dbg(&dev->udev->dev, "%s", __func__);
589 
590 	if (urb->actual_length < sizeof *event)
591 		return;
592 
593 	/* Add cases to handle other standard notifications. */
594 	event = urb->transfer_buffer;
595 	switch (event->bNotificationType) {
596 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
597 	case USB_CDC_NOTIFY_SPEED_CHANGE:
598 		/* USB 305 sends those */
599 		break;
600 	case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
601 		sierra_net_defer_kevent(dev, SIERRA_NET_EVENT_RESP_AVAIL);
602 		break;
603 	default:
604 		netdev_err(dev->net, ": unexpected notification %02x!\n",
605 				event->bNotificationType);
606 		break;
607 	}
608 }
609 
610 static void sierra_net_get_drvinfo(struct net_device *net,
611 		struct ethtool_drvinfo *info)
612 {
613 	/* Inherit standard device info */
614 	usbnet_get_drvinfo(net, info);
615 	strscpy(info->driver, driver_name, sizeof(info->driver));
616 	strscpy(info->version, DRIVER_VERSION, sizeof(info->version));
617 }
618 
619 static u32 sierra_net_get_link(struct net_device *net)
620 {
621 	struct usbnet *dev = netdev_priv(net);
622 	/* Report link is down whenever the interface is down */
623 	return sierra_net_get_private(dev)->link_up && netif_running(net);
624 }
625 
626 static const struct ethtool_ops sierra_net_ethtool_ops = {
627 	.get_drvinfo = sierra_net_get_drvinfo,
628 	.get_link = sierra_net_get_link,
629 	.get_msglevel = usbnet_get_msglevel,
630 	.set_msglevel = usbnet_set_msglevel,
631 	.nway_reset = usbnet_nway_reset,
632 	.get_link_ksettings = usbnet_get_link_ksettings_mii,
633 	.set_link_ksettings = usbnet_set_link_ksettings_mii,
634 };
635 
636 static int sierra_net_get_fw_attr(struct usbnet *dev, u16 *datap)
637 {
638 	int result = 0;
639 	__le16 attrdata;
640 
641 	result = usbnet_read_cmd(dev,
642 				/* _u8 vendor specific request */
643 				SWI_USB_REQUEST_GET_FW_ATTR,
644 				USB_DIR_IN | USB_TYPE_VENDOR,	/* __u8 request type */
645 				0x0000,		/* __u16 value not used */
646 				0x0000,		/* __u16 index  not used */
647 				&attrdata,	/* char *data */
648 				sizeof(attrdata)	/* __u16 size */
649 				);
650 
651 	if (result < 0)
652 		return -EIO;
653 
654 	*datap = le16_to_cpu(attrdata);
655 	return result;
656 }
657 
658 /*
659  * collects the bulk endpoints, the status endpoint.
660  */
661 static int sierra_net_bind(struct usbnet *dev, struct usb_interface *intf)
662 {
663 	u8	ifacenum;
664 	u8	numendpoints;
665 	u16	fwattr = 0;
666 	int	status;
667 	struct sierra_net_data *priv;
668 	static const u8 sync_tmplate[sizeof(priv->sync_msg)] = {
669 		0x00, 0x00, SIERRA_NET_HIP_MSYNC_ID, 0x00};
670 	static const u8 shdwn_tmplate[sizeof(priv->shdwn_msg)] = {
671 		0x00, 0x00, SIERRA_NET_HIP_SHUTD_ID, 0x00};
672 	u8 mod[2];
673 
674 	dev_dbg(&dev->udev->dev, "%s", __func__);
675 
676 	ifacenum = intf->cur_altsetting->desc.bInterfaceNumber;
677 	numendpoints = intf->cur_altsetting->desc.bNumEndpoints;
678 	/* We have three endpoints, bulk in and out, and a status */
679 	if (numendpoints != 3) {
680 		dev_err(&dev->udev->dev, "Expected 3 endpoints, found: %d",
681 			numendpoints);
682 		return -ENODEV;
683 	}
684 	/* Status endpoint set in usbnet_get_endpoints() */
685 	dev->status = NULL;
686 	status = usbnet_get_endpoints(dev, intf);
687 	if (status < 0) {
688 		dev_err(&dev->udev->dev, "Error in usbnet_get_endpoints (%d)",
689 			status);
690 		return -ENODEV;
691 	}
692 	/* Initialize sierra private data */
693 	priv = kzalloc(sizeof *priv, GFP_KERNEL);
694 	if (!priv)
695 		return -ENOMEM;
696 
697 	priv->usbnet = dev;
698 	priv->ifnum = ifacenum;
699 	dev->net->netdev_ops = &sierra_net_device_ops;
700 
701 	/* change MAC addr to include, ifacenum, and to be unique */
702 	mod[0] = atomic_inc_return(&iface_counter);
703 	mod[1] = ifacenum;
704 	dev_addr_mod(dev->net, ETH_ALEN - 2, mod, 2);
705 
706 	/* prepare shutdown message template */
707 	memcpy(priv->shdwn_msg, shdwn_tmplate, sizeof(priv->shdwn_msg));
708 	/* set context index initially to 0 - prepares tx hdr template */
709 	sierra_net_set_ctx_index(priv, 0);
710 
711 	/* prepare sync message template */
712 	memcpy(priv->sync_msg, sync_tmplate, sizeof(priv->sync_msg));
713 
714 	/* decrease the rx_urb_size and max_tx_size to 4k on USB 1.1 */
715 	dev->rx_urb_size  = SIERRA_NET_RX_URB_SIZE;
716 	if (dev->udev->speed != USB_SPEED_HIGH)
717 		dev->rx_urb_size  = min_t(size_t, 4096, SIERRA_NET_RX_URB_SIZE);
718 
719 	dev->net->hard_header_len += SIERRA_NET_HIP_EXT_HDR_LEN;
720 	dev->hard_mtu = dev->net->mtu + dev->net->hard_header_len;
721 	dev->net->max_mtu = SIERRA_NET_MAX_SUPPORTED_MTU;
722 
723 	/* Set up the netdev */
724 	dev->net->flags |= IFF_NOARP;
725 	dev->net->ethtool_ops = &sierra_net_ethtool_ops;
726 	netif_carrier_off(dev->net);
727 
728 	sierra_net_set_private(dev, priv);
729 
730 	priv->kevent_flags = 0;
731 
732 	/* Use the shared workqueue */
733 	INIT_WORK(&priv->sierra_net_kevent, sierra_net_kevent);
734 
735 	/* Only need to do this once */
736 	timer_setup(&priv->sync_timer, sierra_sync_timer, 0);
737 
738 	/* verify fw attributes */
739 	status = sierra_net_get_fw_attr(dev, &fwattr);
740 	dev_dbg(&dev->udev->dev, "Fw attr: %x\n", fwattr);
741 
742 	/* test whether firmware supports DHCP */
743 	if (!(status == sizeof(fwattr) && (fwattr & SWI_GET_FW_ATTR_MASK))) {
744 		/* found incompatible firmware version */
745 		dev_err(&dev->udev->dev, "Incompatible driver and firmware"
746 			" versions\n");
747 		kfree(priv);
748 		return -ENODEV;
749 	}
750 
751 	return 0;
752 }
753 
754 static void sierra_net_unbind(struct usbnet *dev, struct usb_interface *intf)
755 {
756 	int status;
757 	struct sierra_net_data *priv = sierra_net_get_private(dev);
758 
759 	dev_dbg(&dev->udev->dev, "%s", __func__);
760 
761 	/* kill the timer and work */
762 	timer_shutdown_sync(&priv->sync_timer);
763 	cancel_work_sync(&priv->sierra_net_kevent);
764 
765 	/* tell modem we are going away */
766 	status = sierra_net_send_cmd(dev, priv->shdwn_msg,
767 			sizeof(priv->shdwn_msg), "Shutdown");
768 	if (status < 0)
769 		netdev_err(dev->net,
770 			"usb_control_msg failed, status %d\n", status);
771 
772 	usbnet_status_stop(dev);
773 
774 	sierra_net_set_private(dev, NULL);
775 	kfree(priv);
776 }
777 
778 static struct sk_buff *sierra_net_skb_clone(struct usbnet *dev,
779 		struct sk_buff *skb, int len)
780 {
781 	struct sk_buff *new_skb;
782 
783 	/* clone skb */
784 	new_skb = skb_clone(skb, GFP_ATOMIC);
785 
786 	/* remove len bytes from original */
787 	skb_pull(skb, len);
788 
789 	/* trim next packet to it's length */
790 	if (new_skb) {
791 		skb_trim(new_skb, len);
792 	} else {
793 		if (netif_msg_rx_err(dev))
794 			netdev_err(dev->net, "failed to get skb\n");
795 		dev->net->stats.rx_dropped++;
796 	}
797 
798 	return new_skb;
799 }
800 
801 /* ---------------------------- Receive data path ----------------------*/
802 static int sierra_net_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
803 {
804 	int err;
805 	struct hip_hdr  hh;
806 	struct sk_buff *new_skb;
807 
808 	dev_dbg(&dev->udev->dev, "%s", __func__);
809 
810 	/* could contain multiple packets */
811 	while (likely(skb->len)) {
812 		err = parse_hip(skb->data, skb->len, &hh);
813 		if (err) {
814 			if (netif_msg_rx_err(dev))
815 				netdev_err(dev->net, "Invalid HIP header %d\n",
816 					err);
817 			/* dev->net->stats.rx_errors incremented by caller */
818 			dev->net->stats.rx_length_errors++;
819 			return 0;
820 		}
821 
822 		/* Validate Extended HIP header */
823 		if (!hh.extmsgid.is_present
824 		    || hh.extmsgid.word != SIERRA_NET_HIP_EXT_IP_IN_ID) {
825 			if (netif_msg_rx_err(dev))
826 				netdev_err(dev->net, "HIP/ETH: Invalid pkt\n");
827 
828 			dev->net->stats.rx_frame_errors++;
829 			/* dev->net->stats.rx_errors incremented by caller */
830 			return 0;
831 		}
832 
833 		skb_pull(skb, hh.hdrlen);
834 
835 		/* We are going to accept this packet, prepare it.
836 		 * In case protocol is IPv6, keep it, otherwise force IPv4.
837 		 */
838 		skb_reset_mac_header(skb);
839 		if (eth_hdr(skb)->h_proto != cpu_to_be16(ETH_P_IPV6))
840 			eth_hdr(skb)->h_proto = cpu_to_be16(ETH_P_IP);
841 		eth_zero_addr(eth_hdr(skb)->h_source);
842 		memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
843 
844 		/* Last packet in batch handled by usbnet */
845 		if (hh.payload_len.word == skb->len)
846 			return 1;
847 
848 		new_skb = sierra_net_skb_clone(dev, skb, hh.payload_len.word);
849 		if (new_skb)
850 			usbnet_skb_return(dev, new_skb);
851 
852 	} /* while */
853 
854 	return 0;
855 }
856 
857 /* ---------------------------- Transmit data path ----------------------*/
858 static struct sk_buff *sierra_net_tx_fixup(struct usbnet *dev,
859 					   struct sk_buff *skb, gfp_t flags)
860 {
861 	struct sierra_net_data *priv = sierra_net_get_private(dev);
862 	u16 len;
863 	bool need_tail;
864 
865 	BUILD_BUG_ON(sizeof_field(struct usbnet, data)
866 				< sizeof(struct cdc_state));
867 
868 	dev_dbg(&dev->udev->dev, "%s", __func__);
869 	if (priv->link_up && check_ethip_packet(skb, dev) && is_ip(skb)) {
870 		/* enough head room as is? */
871 		if (SIERRA_NET_HIP_EXT_HDR_LEN <= skb_headroom(skb)) {
872 			/* Save the Eth/IP length and set up HIP hdr */
873 			len = skb->len;
874 			skb_push(skb, SIERRA_NET_HIP_EXT_HDR_LEN);
875 			/* Handle ZLP issue */
876 			need_tail = ((len + SIERRA_NET_HIP_EXT_HDR_LEN)
877 				% dev->maxpacket == 0);
878 			if (need_tail) {
879 				if (unlikely(skb_tailroom(skb) == 0)) {
880 					netdev_err(dev->net, "tx_fixup:"
881 						"no room for packet\n");
882 					dev_kfree_skb_any(skb);
883 					return NULL;
884 				} else {
885 					skb->data[skb->len] = 0;
886 					__skb_put(skb, 1);
887 					len = len + 1;
888 				}
889 			}
890 			build_hip(skb->data, len, priv);
891 			return skb;
892 		} else {
893 			/*
894 			 * compensate in the future if necessary
895 			 */
896 			netdev_err(dev->net, "tx_fixup: no room for HIP\n");
897 		} /* headroom */
898 	}
899 
900 	if (!priv->link_up)
901 		dev->net->stats.tx_carrier_errors++;
902 
903 	/* tx_dropped incremented by usbnet */
904 
905 	/* filter the packet out, release it  */
906 	dev_kfree_skb_any(skb);
907 	return NULL;
908 }
909 
910 static const struct driver_info sierra_net_info_direct_ip = {
911 	.description = "Sierra Wireless USB-to-WWAN Modem",
912 	.flags = FLAG_WWAN | FLAG_SEND_ZLP,
913 	.bind = sierra_net_bind,
914 	.unbind = sierra_net_unbind,
915 	.status = sierra_net_status,
916 	.rx_fixup = sierra_net_rx_fixup,
917 	.tx_fixup = sierra_net_tx_fixup,
918 };
919 
920 static int
921 sierra_net_probe(struct usb_interface *udev, const struct usb_device_id *prod)
922 {
923 	int ret;
924 
925 	ret = usbnet_probe(udev, prod);
926 	if (ret == 0) {
927 		struct usbnet *dev = usb_get_intfdata(udev);
928 
929 		ret = usbnet_status_start(dev, GFP_KERNEL);
930 		if (ret == 0) {
931 			/* Interrupt URB now set up; initiate sync sequence */
932 			sierra_net_dosync(dev);
933 		}
934 	}
935 	return ret;
936 }
937 
938 #define DIRECT_IP_DEVICE(vend, prod) \
939 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 7), \
940 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
941 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 10), \
942 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
943 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 11), \
944 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}
945 
946 static const struct usb_device_id products[] = {
947 	DIRECT_IP_DEVICE(0x1199, 0x68A3), /* Sierra Wireless USB-to-WWAN modem */
948 	DIRECT_IP_DEVICE(0x0F3D, 0x68A3), /* AT&T Direct IP modem */
949 	DIRECT_IP_DEVICE(0x1199, 0x68AA), /* Sierra Wireless Direct IP LTE modem */
950 	DIRECT_IP_DEVICE(0x0F3D, 0x68AA), /* AT&T Direct IP LTE modem */
951 
952 	{}, /* last item */
953 };
954 MODULE_DEVICE_TABLE(usb, products);
955 
956 /* We are based on usbnet, so let it handle the USB driver specifics */
957 static struct usb_driver sierra_net_driver = {
958 	.name = "sierra_net",
959 	.id_table = products,
960 	.probe = sierra_net_probe,
961 	.disconnect = usbnet_disconnect,
962 	.suspend = usbnet_suspend,
963 	.resume = usbnet_resume,
964 	.no_dynamic_id = 1,
965 	.disable_hub_initiated_lpm = 1,
966 };
967 
968 module_usb_driver(sierra_net_driver);
969 
970 MODULE_AUTHOR(DRIVER_AUTHOR);
971 MODULE_DESCRIPTION(DRIVER_DESC);
972 MODULE_VERSION(DRIVER_VERSION);
973 MODULE_LICENSE("GPL");
974