xref: /linux/drivers/net/usb/sierra_net.c (revision 9a379e77033f02c4a071891afdf0f0a01eff8ccb)
1 /*
2  * USB-to-WWAN Driver for Sierra Wireless modems
3  *
4  * Copyright (C) 2008, 2009, 2010 Paxton Smith, Matthew Safar, Rory Filer
5  *                          <linux@sierrawireless.com>
6  *
7  * Portions of this based on the cdc_ether driver by David Brownell (2003-2005)
8  * and Ole Andre Vadla Ravnas (ActiveSync) (2006).
9  *
10  * IMPORTANT DISCLAIMER: This driver is not commercially supported by
11  * Sierra Wireless. Use at your own risk.
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, see <http://www.gnu.org/licenses/>.
25  */
26 
27 #define DRIVER_VERSION "v.2.0"
28 #define DRIVER_AUTHOR "Paxton Smith, Matthew Safar, Rory Filer"
29 #define DRIVER_DESC "USB-to-WWAN Driver for Sierra Wireless modems"
30 static const char driver_name[] = "sierra_net";
31 
32 /* if defined debug messages enabled */
33 /*#define	DEBUG*/
34 
35 #include <linux/module.h>
36 #include <linux/etherdevice.h>
37 #include <linux/ethtool.h>
38 #include <linux/mii.h>
39 #include <linux/sched.h>
40 #include <linux/timer.h>
41 #include <linux/usb.h>
42 #include <linux/usb/cdc.h>
43 #include <net/ip.h>
44 #include <net/udp.h>
45 #include <asm/unaligned.h>
46 #include <linux/usb/usbnet.h>
47 
48 #define SWI_USB_REQUEST_GET_FW_ATTR	0x06
49 #define SWI_GET_FW_ATTR_MASK		0x08
50 
51 /* atomic counter partially included in MAC address to make sure 2 devices
52  * do not end up with the same MAC - concept breaks in case of > 255 ifaces
53  */
54 static	atomic_t iface_counter = ATOMIC_INIT(0);
55 
56 /*
57  * SYNC Timer Delay definition used to set the expiry time
58  */
59 #define SIERRA_NET_SYNCDELAY (2*HZ)
60 
61 /* Max. MTU supported. The modem buffers are limited to 1500 */
62 #define SIERRA_NET_MAX_SUPPORTED_MTU	1500
63 
64 /* The SIERRA_NET_USBCTL_BUF_LEN defines a buffer size allocated for control
65  * message reception ... and thus the max. received packet.
66  * (May be the cause for parse_hip returning -EINVAL)
67  */
68 #define SIERRA_NET_USBCTL_BUF_LEN	1024
69 
70 /* Overriding the default usbnet rx_urb_size */
71 #define SIERRA_NET_RX_URB_SIZE		(8 * 1024)
72 
73 /* Private data structure */
74 struct sierra_net_data {
75 
76 	u16 link_up;		/* air link up or down */
77 	u8 tx_hdr_template[4];	/* part of HIP hdr for tx'd packets */
78 
79 	u8 sync_msg[4];		/* SYNC message */
80 	u8 shdwn_msg[4];	/* Shutdown message */
81 
82 	/* Backpointer to the container */
83 	struct usbnet *usbnet;
84 
85 	u8 ifnum;	/* interface number */
86 
87 /* Bit masks, must be a power of 2 */
88 #define SIERRA_NET_EVENT_RESP_AVAIL    0x01
89 #define SIERRA_NET_TIMER_EXPIRY        0x02
90 	unsigned long kevent_flags;
91 	struct work_struct sierra_net_kevent;
92 	struct timer_list sync_timer; /* For retrying SYNC sequence */
93 };
94 
95 struct param {
96 	int is_present;
97 	union {
98 		void  *ptr;
99 		u32    dword;
100 		u16    word;
101 		u8     byte;
102 	};
103 };
104 
105 /* HIP message type */
106 #define SIERRA_NET_HIP_EXTENDEDID	0x7F
107 #define SIERRA_NET_HIP_HSYNC_ID		0x60	/* Modem -> host */
108 #define SIERRA_NET_HIP_RESTART_ID	0x62	/* Modem -> host */
109 #define SIERRA_NET_HIP_MSYNC_ID		0x20	/* Host -> modem */
110 #define SIERRA_NET_HIP_SHUTD_ID		0x26	/* Host -> modem */
111 
112 #define SIERRA_NET_HIP_EXT_IP_IN_ID   0x0202
113 #define SIERRA_NET_HIP_EXT_IP_OUT_ID  0x0002
114 
115 /* 3G UMTS Link Sense Indication definitions */
116 #define SIERRA_NET_HIP_LSI_UMTSID	0x78
117 
118 /* Reverse Channel Grant Indication HIP message */
119 #define SIERRA_NET_HIP_RCGI		0x64
120 
121 /* LSI Protocol types */
122 #define SIERRA_NET_PROTOCOL_UMTS      0x01
123 #define SIERRA_NET_PROTOCOL_UMTS_DS   0x04
124 /* LSI Coverage */
125 #define SIERRA_NET_COVERAGE_NONE      0x00
126 #define SIERRA_NET_COVERAGE_NOPACKET  0x01
127 
128 /* LSI Session */
129 #define SIERRA_NET_SESSION_IDLE       0x00
130 /* LSI Link types */
131 #define SIERRA_NET_AS_LINK_TYPE_IPV4  0x00
132 #define SIERRA_NET_AS_LINK_TYPE_IPV6  0x02
133 
134 struct lsi_umts {
135 	u8 protocol;
136 	u8 unused1;
137 	__be16 length;
138 	/* eventually use a union for the rest - assume umts for now */
139 	u8 coverage;
140 	u8 network_len; /* network name len */
141 	u8 network[40]; /* network name (UCS2, bigendian) */
142 	u8 session_state;
143 	u8 unused3[33];
144 } __packed;
145 
146 struct lsi_umts_single {
147 	struct lsi_umts lsi;
148 	u8 link_type;
149 	u8 pdp_addr_len; /* NW-supplied PDP address len */
150 	u8 pdp_addr[16]; /* NW-supplied PDP address (bigendian)) */
151 	u8 unused4[23];
152 	u8 dns1_addr_len; /* NW-supplied 1st DNS address len (bigendian) */
153 	u8 dns1_addr[16]; /* NW-supplied 1st DNS address */
154 	u8 dns2_addr_len; /* NW-supplied 2nd DNS address len */
155 	u8 dns2_addr[16]; /* NW-supplied 2nd DNS address (bigendian)*/
156 	u8 wins1_addr_len; /* NW-supplied 1st Wins address len */
157 	u8 wins1_addr[16]; /* NW-supplied 1st Wins address (bigendian)*/
158 	u8 wins2_addr_len; /* NW-supplied 2nd Wins address len */
159 	u8 wins2_addr[16]; /* NW-supplied 2nd Wins address (bigendian) */
160 	u8 unused5[4];
161 	u8 gw_addr_len; /* NW-supplied GW address len */
162 	u8 gw_addr[16]; /* NW-supplied GW address (bigendian) */
163 	u8 reserved[8];
164 } __packed;
165 
166 struct lsi_umts_dual {
167 	struct lsi_umts lsi;
168 	u8 pdp_addr4_len; /* NW-supplied PDP IPv4 address len */
169 	u8 pdp_addr4[4];  /* NW-supplied PDP IPv4 address (bigendian)) */
170 	u8 pdp_addr6_len; /* NW-supplied PDP IPv6 address len */
171 	u8 pdp_addr6[16]; /* NW-supplied PDP IPv6 address (bigendian)) */
172 	u8 unused4[23];
173 	u8 dns1_addr4_len; /* NW-supplied 1st DNS v4 address len (bigendian) */
174 	u8 dns1_addr4[4];  /* NW-supplied 1st DNS v4 address */
175 	u8 dns1_addr6_len; /* NW-supplied 1st DNS v6 address len */
176 	u8 dns1_addr6[16]; /* NW-supplied 1st DNS v6 address (bigendian)*/
177 	u8 dns2_addr4_len; /* NW-supplied 2nd DNS v4 address len (bigendian) */
178 	u8 dns2_addr4[4];  /* NW-supplied 2nd DNS v4 address */
179 	u8 dns2_addr6_len; /* NW-supplied 2nd DNS v6 address len */
180 	u8 dns2_addr6[16]; /* NW-supplied 2nd DNS v6 address (bigendian)*/
181 	u8 unused5[68];
182 } __packed;
183 
184 #define SIERRA_NET_LSI_COMMON_LEN      4
185 #define SIERRA_NET_LSI_UMTS_LEN        (sizeof(struct lsi_umts_single))
186 #define SIERRA_NET_LSI_UMTS_STATUS_LEN \
187 	(SIERRA_NET_LSI_UMTS_LEN - SIERRA_NET_LSI_COMMON_LEN)
188 #define SIERRA_NET_LSI_UMTS_DS_LEN     (sizeof(struct lsi_umts_dual))
189 #define SIERRA_NET_LSI_UMTS_DS_STATUS_LEN \
190 	(SIERRA_NET_LSI_UMTS_DS_LEN - SIERRA_NET_LSI_COMMON_LEN)
191 
192 /* Our own net device operations structure */
193 static const struct net_device_ops sierra_net_device_ops = {
194 	.ndo_open               = usbnet_open,
195 	.ndo_stop               = usbnet_stop,
196 	.ndo_start_xmit         = usbnet_start_xmit,
197 	.ndo_tx_timeout         = usbnet_tx_timeout,
198 	.ndo_change_mtu         = usbnet_change_mtu,
199 	.ndo_get_stats64        = usbnet_get_stats64,
200 	.ndo_set_mac_address    = eth_mac_addr,
201 	.ndo_validate_addr      = eth_validate_addr,
202 };
203 
204 /* get private data associated with passed in usbnet device */
205 static inline struct sierra_net_data *sierra_net_get_private(struct usbnet *dev)
206 {
207 	return (struct sierra_net_data *)dev->data[0];
208 }
209 
210 /* set private data associated with passed in usbnet device */
211 static inline void sierra_net_set_private(struct usbnet *dev,
212 			struct sierra_net_data *priv)
213 {
214 	dev->data[0] = (unsigned long)priv;
215 }
216 
217 /* is packet IPv4/IPv6 */
218 static inline int is_ip(struct sk_buff *skb)
219 {
220 	return skb->protocol == cpu_to_be16(ETH_P_IP) ||
221 	       skb->protocol == cpu_to_be16(ETH_P_IPV6);
222 }
223 
224 /*
225  * check passed in packet and make sure that:
226  *  - it is linear (no scatter/gather)
227  *  - it is ethernet (mac_header properly set)
228  */
229 static int check_ethip_packet(struct sk_buff *skb, struct usbnet *dev)
230 {
231 	skb_reset_mac_header(skb); /* ethernet header */
232 
233 	if (skb_is_nonlinear(skb)) {
234 		netdev_err(dev->net, "Non linear buffer-dropping\n");
235 		return 0;
236 	}
237 
238 	if (!pskb_may_pull(skb, ETH_HLEN))
239 		return 0;
240 	skb->protocol = eth_hdr(skb)->h_proto;
241 
242 	return 1;
243 }
244 
245 static const u8 *save16bit(struct param *p, const u8 *datap)
246 {
247 	p->is_present = 1;
248 	p->word = get_unaligned_be16(datap);
249 	return datap + sizeof(p->word);
250 }
251 
252 static const u8 *save8bit(struct param *p, const u8 *datap)
253 {
254 	p->is_present = 1;
255 	p->byte = *datap;
256 	return datap + sizeof(p->byte);
257 }
258 
259 /*----------------------------------------------------------------------------*
260  *                              BEGIN HIP                                     *
261  *----------------------------------------------------------------------------*/
262 /* HIP header */
263 #define SIERRA_NET_HIP_HDR_LEN 4
264 /* Extended HIP header */
265 #define SIERRA_NET_HIP_EXT_HDR_LEN 6
266 
267 struct hip_hdr {
268 	int    hdrlen;
269 	struct param payload_len;
270 	struct param msgid;
271 	struct param msgspecific;
272 	struct param extmsgid;
273 };
274 
275 static int parse_hip(const u8 *buf, const u32 buflen, struct hip_hdr *hh)
276 {
277 	const u8 *curp = buf;
278 	int    padded;
279 
280 	if (buflen < SIERRA_NET_HIP_HDR_LEN)
281 		return -EPROTO;
282 
283 	curp = save16bit(&hh->payload_len, curp);
284 	curp = save8bit(&hh->msgid, curp);
285 	curp = save8bit(&hh->msgspecific, curp);
286 
287 	padded = hh->msgid.byte & 0x80;
288 	hh->msgid.byte &= 0x7F;			/* 7 bits */
289 
290 	hh->extmsgid.is_present = (hh->msgid.byte == SIERRA_NET_HIP_EXTENDEDID);
291 	if (hh->extmsgid.is_present) {
292 		if (buflen < SIERRA_NET_HIP_EXT_HDR_LEN)
293 			return -EPROTO;
294 
295 		hh->payload_len.word &= 0x3FFF; /* 14 bits */
296 
297 		curp = save16bit(&hh->extmsgid, curp);
298 		hh->extmsgid.word &= 0x03FF;	/* 10 bits */
299 
300 		hh->hdrlen = SIERRA_NET_HIP_EXT_HDR_LEN;
301 	} else {
302 		hh->payload_len.word &= 0x07FF;	/* 11 bits */
303 		hh->hdrlen = SIERRA_NET_HIP_HDR_LEN;
304 	}
305 
306 	if (padded) {
307 		hh->hdrlen++;
308 		hh->payload_len.word--;
309 	}
310 
311 	/* if real packet shorter than the claimed length */
312 	if (buflen < (hh->hdrlen + hh->payload_len.word))
313 		return -EINVAL;
314 
315 	return 0;
316 }
317 
318 static void build_hip(u8 *buf, const u16 payloadlen,
319 		struct sierra_net_data *priv)
320 {
321 	/* the following doesn't have the full functionality. We
322 	 * currently build only one kind of header, so it is faster this way
323 	 */
324 	put_unaligned_be16(payloadlen, buf);
325 	memcpy(buf+2, priv->tx_hdr_template, sizeof(priv->tx_hdr_template));
326 }
327 /*----------------------------------------------------------------------------*
328  *                              END HIP                                       *
329  *----------------------------------------------------------------------------*/
330 
331 static int sierra_net_send_cmd(struct usbnet *dev,
332 		u8 *cmd, int cmdlen, const char * cmd_name)
333 {
334 	struct sierra_net_data *priv = sierra_net_get_private(dev);
335 	int  status;
336 
337 	status = usbnet_write_cmd(dev, USB_CDC_SEND_ENCAPSULATED_COMMAND,
338 				  USB_DIR_OUT|USB_TYPE_CLASS|USB_RECIP_INTERFACE,
339 				  0, priv->ifnum, cmd, cmdlen);
340 
341 	if (status != cmdlen && status != -ENODEV)
342 		netdev_err(dev->net, "Submit %s failed %d\n", cmd_name, status);
343 
344 	return status;
345 }
346 
347 static int sierra_net_send_sync(struct usbnet *dev)
348 {
349 	int  status;
350 	struct sierra_net_data *priv = sierra_net_get_private(dev);
351 
352 	dev_dbg(&dev->udev->dev, "%s", __func__);
353 
354 	status = sierra_net_send_cmd(dev, priv->sync_msg,
355 			sizeof(priv->sync_msg), "SYNC");
356 
357 	return status;
358 }
359 
360 static void sierra_net_set_ctx_index(struct sierra_net_data *priv, u8 ctx_ix)
361 {
362 	dev_dbg(&(priv->usbnet->udev->dev), "%s %d", __func__, ctx_ix);
363 	priv->tx_hdr_template[0] = 0x3F;
364 	priv->tx_hdr_template[1] = ctx_ix;
365 	*((__be16 *)&priv->tx_hdr_template[2]) =
366 		cpu_to_be16(SIERRA_NET_HIP_EXT_IP_OUT_ID);
367 }
368 
369 static inline int sierra_net_is_valid_addrlen(u8 len)
370 {
371 	return len == sizeof(struct in_addr);
372 }
373 
374 static int sierra_net_parse_lsi(struct usbnet *dev, char *data, int datalen)
375 {
376 	struct lsi_umts *lsi = (struct lsi_umts *)data;
377 	u32 expected_length;
378 
379 	if (datalen < sizeof(struct lsi_umts_single)) {
380 		netdev_err(dev->net, "%s: Data length %d, exp >= %zu\n",
381 			   __func__, datalen, sizeof(struct lsi_umts_single));
382 		return -1;
383 	}
384 
385 	/* Validate the session state */
386 	if (lsi->session_state == SIERRA_NET_SESSION_IDLE) {
387 		netdev_err(dev->net, "Session idle, 0x%02x\n",
388 			   lsi->session_state);
389 		return 0;
390 	}
391 
392 	/* Validate the protocol  - only support UMTS for now */
393 	if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS) {
394 		struct lsi_umts_single *single = (struct lsi_umts_single *)lsi;
395 
396 		/* Validate the link type */
397 		if (single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV4 &&
398 		    single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV6) {
399 			netdev_err(dev->net, "Link type unsupported: 0x%02x\n",
400 				   single->link_type);
401 			return -1;
402 		}
403 		expected_length = SIERRA_NET_LSI_UMTS_STATUS_LEN;
404 	} else if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS_DS) {
405 		expected_length = SIERRA_NET_LSI_UMTS_DS_STATUS_LEN;
406 	} else {
407 		netdev_err(dev->net, "Protocol unsupported, 0x%02x\n",
408 			   lsi->protocol);
409 		return -1;
410 	}
411 
412 	if (be16_to_cpu(lsi->length) != expected_length) {
413 		netdev_err(dev->net, "%s: LSI_UMTS_STATUS_LEN %d, exp %u\n",
414 			   __func__, be16_to_cpu(lsi->length), expected_length);
415 		return -1;
416 	}
417 
418 	/* Validate the coverage */
419 	if (lsi->coverage == SIERRA_NET_COVERAGE_NONE ||
420 	    lsi->coverage == SIERRA_NET_COVERAGE_NOPACKET) {
421 		netdev_err(dev->net, "No coverage, 0x%02x\n", lsi->coverage);
422 		return 0;
423 	}
424 
425 	/* Set link_sense true */
426 	return 1;
427 }
428 
429 static void sierra_net_handle_lsi(struct usbnet *dev, char *data,
430 		struct hip_hdr	*hh)
431 {
432 	struct sierra_net_data *priv = sierra_net_get_private(dev);
433 	int link_up;
434 
435 	link_up = sierra_net_parse_lsi(dev, data + hh->hdrlen,
436 					hh->payload_len.word);
437 	if (link_up < 0) {
438 		netdev_err(dev->net, "Invalid LSI\n");
439 		return;
440 	}
441 	if (link_up) {
442 		sierra_net_set_ctx_index(priv, hh->msgspecific.byte);
443 		priv->link_up = 1;
444 	} else {
445 		priv->link_up = 0;
446 	}
447 	usbnet_link_change(dev, link_up, 0);
448 }
449 
450 static void sierra_net_dosync(struct usbnet *dev)
451 {
452 	int status;
453 	struct sierra_net_data *priv = sierra_net_get_private(dev);
454 
455 	dev_dbg(&dev->udev->dev, "%s", __func__);
456 
457 	/* The SIERRA_NET_HIP_MSYNC_ID command appears to request that the
458 	 * firmware restart itself.  After restarting, the modem will respond
459 	 * with the SIERRA_NET_HIP_RESTART_ID indication.  The driver continues
460 	 * sending MSYNC commands every few seconds until it receives the
461 	 * RESTART event from the firmware
462 	 */
463 
464 	/* tell modem we are ready */
465 	status = sierra_net_send_sync(dev);
466 	if (status < 0)
467 		netdev_err(dev->net,
468 			"Send SYNC failed, status %d\n", status);
469 	status = sierra_net_send_sync(dev);
470 	if (status < 0)
471 		netdev_err(dev->net,
472 			"Send SYNC failed, status %d\n", status);
473 
474 	/* Now, start a timer and make sure we get the Restart Indication */
475 	priv->sync_timer.expires = jiffies + SIERRA_NET_SYNCDELAY;
476 	add_timer(&priv->sync_timer);
477 }
478 
479 static void sierra_net_kevent(struct work_struct *work)
480 {
481 	struct sierra_net_data *priv =
482 		container_of(work, struct sierra_net_data, sierra_net_kevent);
483 	struct usbnet *dev = priv->usbnet;
484 	int  len;
485 	int  err;
486 	u8  *buf;
487 	u8   ifnum;
488 
489 	if (test_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags)) {
490 		clear_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags);
491 
492 		/* Query the modem for the LSI message */
493 		buf = kzalloc(SIERRA_NET_USBCTL_BUF_LEN, GFP_KERNEL);
494 		if (!buf)
495 			return;
496 
497 		ifnum = priv->ifnum;
498 		len = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
499 				USB_CDC_GET_ENCAPSULATED_RESPONSE,
500 				USB_DIR_IN|USB_TYPE_CLASS|USB_RECIP_INTERFACE,
501 				0, ifnum, buf, SIERRA_NET_USBCTL_BUF_LEN,
502 				USB_CTRL_SET_TIMEOUT);
503 
504 		if (len < 0) {
505 			netdev_err(dev->net,
506 				"usb_control_msg failed, status %d\n", len);
507 		} else {
508 			struct hip_hdr	hh;
509 
510 			dev_dbg(&dev->udev->dev, "%s: Received status message,"
511 				" %04x bytes", __func__, len);
512 
513 			err = parse_hip(buf, len, &hh);
514 			if (err) {
515 				netdev_err(dev->net, "%s: Bad packet,"
516 					" parse result %d\n", __func__, err);
517 				kfree(buf);
518 				return;
519 			}
520 
521 			/* Validate packet length */
522 			if (len != hh.hdrlen + hh.payload_len.word) {
523 				netdev_err(dev->net, "%s: Bad packet, received"
524 					" %d, expected %d\n",	__func__, len,
525 					hh.hdrlen + hh.payload_len.word);
526 				kfree(buf);
527 				return;
528 			}
529 
530 			/* Switch on received message types */
531 			switch (hh.msgid.byte) {
532 			case SIERRA_NET_HIP_LSI_UMTSID:
533 				dev_dbg(&dev->udev->dev, "LSI for ctx:%d",
534 					hh.msgspecific.byte);
535 				sierra_net_handle_lsi(dev, buf, &hh);
536 				break;
537 			case SIERRA_NET_HIP_RESTART_ID:
538 				dev_dbg(&dev->udev->dev, "Restart reported: %d,"
539 						" stopping sync timer",
540 						hh.msgspecific.byte);
541 				/* Got sync resp - stop timer & clear mask */
542 				del_timer_sync(&priv->sync_timer);
543 				clear_bit(SIERRA_NET_TIMER_EXPIRY,
544 					  &priv->kevent_flags);
545 				break;
546 			case SIERRA_NET_HIP_HSYNC_ID:
547 				dev_dbg(&dev->udev->dev, "SYNC received");
548 				err = sierra_net_send_sync(dev);
549 				if (err < 0)
550 					netdev_err(dev->net,
551 						"Send SYNC failed %d\n", err);
552 				break;
553 			case SIERRA_NET_HIP_EXTENDEDID:
554 				netdev_err(dev->net, "Unrecognized HIP msg, "
555 					"extmsgid 0x%04x\n", hh.extmsgid.word);
556 				break;
557 			case SIERRA_NET_HIP_RCGI:
558 				/* Ignored */
559 				break;
560 			default:
561 				netdev_err(dev->net, "Unrecognized HIP msg, "
562 					"msgid 0x%02x\n", hh.msgid.byte);
563 				break;
564 			}
565 		}
566 		kfree(buf);
567 	}
568 	/* The sync timer bit might be set */
569 	if (test_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags)) {
570 		clear_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags);
571 		dev_dbg(&dev->udev->dev, "Deferred sync timer expiry");
572 		sierra_net_dosync(priv->usbnet);
573 	}
574 
575 	if (priv->kevent_flags)
576 		dev_dbg(&dev->udev->dev, "sierra_net_kevent done, "
577 			"kevent_flags = 0x%lx", priv->kevent_flags);
578 }
579 
580 static void sierra_net_defer_kevent(struct usbnet *dev, int work)
581 {
582 	struct sierra_net_data *priv = sierra_net_get_private(dev);
583 
584 	set_bit(work, &priv->kevent_flags);
585 	schedule_work(&priv->sierra_net_kevent);
586 }
587 
588 /*
589  * Sync Retransmit Timer Handler. On expiry, kick the work queue
590  */
591 static void sierra_sync_timer(struct timer_list *t)
592 {
593 	struct sierra_net_data *priv = from_timer(priv, t, sync_timer);
594 	struct usbnet *dev = priv->usbnet;
595 
596 	dev_dbg(&dev->udev->dev, "%s", __func__);
597 	/* Kick the tasklet */
598 	sierra_net_defer_kevent(dev, SIERRA_NET_TIMER_EXPIRY);
599 }
600 
601 static void sierra_net_status(struct usbnet *dev, struct urb *urb)
602 {
603 	struct usb_cdc_notification *event;
604 
605 	dev_dbg(&dev->udev->dev, "%s", __func__);
606 
607 	if (urb->actual_length < sizeof *event)
608 		return;
609 
610 	/* Add cases to handle other standard notifications. */
611 	event = urb->transfer_buffer;
612 	switch (event->bNotificationType) {
613 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
614 	case USB_CDC_NOTIFY_SPEED_CHANGE:
615 		/* USB 305 sends those */
616 		break;
617 	case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
618 		sierra_net_defer_kevent(dev, SIERRA_NET_EVENT_RESP_AVAIL);
619 		break;
620 	default:
621 		netdev_err(dev->net, ": unexpected notification %02x!\n",
622 				event->bNotificationType);
623 		break;
624 	}
625 }
626 
627 static void sierra_net_get_drvinfo(struct net_device *net,
628 		struct ethtool_drvinfo *info)
629 {
630 	/* Inherit standard device info */
631 	usbnet_get_drvinfo(net, info);
632 	strlcpy(info->driver, driver_name, sizeof(info->driver));
633 	strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
634 }
635 
636 static u32 sierra_net_get_link(struct net_device *net)
637 {
638 	struct usbnet *dev = netdev_priv(net);
639 	/* Report link is down whenever the interface is down */
640 	return sierra_net_get_private(dev)->link_up && netif_running(net);
641 }
642 
643 static const struct ethtool_ops sierra_net_ethtool_ops = {
644 	.get_drvinfo = sierra_net_get_drvinfo,
645 	.get_link = sierra_net_get_link,
646 	.get_msglevel = usbnet_get_msglevel,
647 	.set_msglevel = usbnet_set_msglevel,
648 	.nway_reset = usbnet_nway_reset,
649 	.get_link_ksettings = usbnet_get_link_ksettings,
650 	.set_link_ksettings = usbnet_set_link_ksettings,
651 };
652 
653 static int sierra_net_get_fw_attr(struct usbnet *dev, u16 *datap)
654 {
655 	int result = 0;
656 	__le16 attrdata;
657 
658 	result = usbnet_read_cmd(dev,
659 				/* _u8 vendor specific request */
660 				SWI_USB_REQUEST_GET_FW_ATTR,
661 				USB_DIR_IN | USB_TYPE_VENDOR,	/* __u8 request type */
662 				0x0000,		/* __u16 value not used */
663 				0x0000,		/* __u16 index  not used */
664 				&attrdata,	/* char *data */
665 				sizeof(attrdata)	/* __u16 size */
666 				);
667 
668 	if (result < 0)
669 		return -EIO;
670 
671 	*datap = le16_to_cpu(attrdata);
672 	return result;
673 }
674 
675 /*
676  * collects the bulk endpoints, the status endpoint.
677  */
678 static int sierra_net_bind(struct usbnet *dev, struct usb_interface *intf)
679 {
680 	u8	ifacenum;
681 	u8	numendpoints;
682 	u16	fwattr = 0;
683 	int	status;
684 	struct sierra_net_data *priv;
685 	static const u8 sync_tmplate[sizeof(priv->sync_msg)] = {
686 		0x00, 0x00, SIERRA_NET_HIP_MSYNC_ID, 0x00};
687 	static const u8 shdwn_tmplate[sizeof(priv->shdwn_msg)] = {
688 		0x00, 0x00, SIERRA_NET_HIP_SHUTD_ID, 0x00};
689 
690 	dev_dbg(&dev->udev->dev, "%s", __func__);
691 
692 	ifacenum = intf->cur_altsetting->desc.bInterfaceNumber;
693 	numendpoints = intf->cur_altsetting->desc.bNumEndpoints;
694 	/* We have three endpoints, bulk in and out, and a status */
695 	if (numendpoints != 3) {
696 		dev_err(&dev->udev->dev, "Expected 3 endpoints, found: %d",
697 			numendpoints);
698 		return -ENODEV;
699 	}
700 	/* Status endpoint set in usbnet_get_endpoints() */
701 	dev->status = NULL;
702 	status = usbnet_get_endpoints(dev, intf);
703 	if (status < 0) {
704 		dev_err(&dev->udev->dev, "Error in usbnet_get_endpoints (%d)",
705 			status);
706 		return -ENODEV;
707 	}
708 	/* Initialize sierra private data */
709 	priv = kzalloc(sizeof *priv, GFP_KERNEL);
710 	if (!priv)
711 		return -ENOMEM;
712 
713 	priv->usbnet = dev;
714 	priv->ifnum = ifacenum;
715 	dev->net->netdev_ops = &sierra_net_device_ops;
716 
717 	/* change MAC addr to include, ifacenum, and to be unique */
718 	dev->net->dev_addr[ETH_ALEN-2] = atomic_inc_return(&iface_counter);
719 	dev->net->dev_addr[ETH_ALEN-1] = ifacenum;
720 
721 	/* prepare shutdown message template */
722 	memcpy(priv->shdwn_msg, shdwn_tmplate, sizeof(priv->shdwn_msg));
723 	/* set context index initially to 0 - prepares tx hdr template */
724 	sierra_net_set_ctx_index(priv, 0);
725 
726 	/* prepare sync message template */
727 	memcpy(priv->sync_msg, sync_tmplate, sizeof(priv->sync_msg));
728 
729 	/* decrease the rx_urb_size and max_tx_size to 4k on USB 1.1 */
730 	dev->rx_urb_size  = SIERRA_NET_RX_URB_SIZE;
731 	if (dev->udev->speed != USB_SPEED_HIGH)
732 		dev->rx_urb_size  = min_t(size_t, 4096, SIERRA_NET_RX_URB_SIZE);
733 
734 	dev->net->hard_header_len += SIERRA_NET_HIP_EXT_HDR_LEN;
735 	dev->hard_mtu = dev->net->mtu + dev->net->hard_header_len;
736 	dev->net->max_mtu = SIERRA_NET_MAX_SUPPORTED_MTU;
737 
738 	/* Set up the netdev */
739 	dev->net->flags |= IFF_NOARP;
740 	dev->net->ethtool_ops = &sierra_net_ethtool_ops;
741 	netif_carrier_off(dev->net);
742 
743 	sierra_net_set_private(dev, priv);
744 
745 	priv->kevent_flags = 0;
746 
747 	/* Use the shared workqueue */
748 	INIT_WORK(&priv->sierra_net_kevent, sierra_net_kevent);
749 
750 	/* Only need to do this once */
751 	timer_setup(&priv->sync_timer, sierra_sync_timer, 0);
752 
753 	/* verify fw attributes */
754 	status = sierra_net_get_fw_attr(dev, &fwattr);
755 	dev_dbg(&dev->udev->dev, "Fw attr: %x\n", fwattr);
756 
757 	/* test whether firmware supports DHCP */
758 	if (!(status == sizeof(fwattr) && (fwattr & SWI_GET_FW_ATTR_MASK))) {
759 		/* found incompatible firmware version */
760 		dev_err(&dev->udev->dev, "Incompatible driver and firmware"
761 			" versions\n");
762 		kfree(priv);
763 		return -ENODEV;
764 	}
765 
766 	return 0;
767 }
768 
769 static void sierra_net_unbind(struct usbnet *dev, struct usb_interface *intf)
770 {
771 	int status;
772 	struct sierra_net_data *priv = sierra_net_get_private(dev);
773 
774 	dev_dbg(&dev->udev->dev, "%s", __func__);
775 
776 	/* kill the timer and work */
777 	del_timer_sync(&priv->sync_timer);
778 	cancel_work_sync(&priv->sierra_net_kevent);
779 
780 	/* tell modem we are going away */
781 	status = sierra_net_send_cmd(dev, priv->shdwn_msg,
782 			sizeof(priv->shdwn_msg), "Shutdown");
783 	if (status < 0)
784 		netdev_err(dev->net,
785 			"usb_control_msg failed, status %d\n", status);
786 
787 	usbnet_status_stop(dev);
788 
789 	sierra_net_set_private(dev, NULL);
790 	kfree(priv);
791 }
792 
793 static struct sk_buff *sierra_net_skb_clone(struct usbnet *dev,
794 		struct sk_buff *skb, int len)
795 {
796 	struct sk_buff *new_skb;
797 
798 	/* clone skb */
799 	new_skb = skb_clone(skb, GFP_ATOMIC);
800 
801 	/* remove len bytes from original */
802 	skb_pull(skb, len);
803 
804 	/* trim next packet to it's length */
805 	if (new_skb) {
806 		skb_trim(new_skb, len);
807 	} else {
808 		if (netif_msg_rx_err(dev))
809 			netdev_err(dev->net, "failed to get skb\n");
810 		dev->net->stats.rx_dropped++;
811 	}
812 
813 	return new_skb;
814 }
815 
816 /* ---------------------------- Receive data path ----------------------*/
817 static int sierra_net_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
818 {
819 	int err;
820 	struct hip_hdr  hh;
821 	struct sk_buff *new_skb;
822 
823 	dev_dbg(&dev->udev->dev, "%s", __func__);
824 
825 	/* could contain multiple packets */
826 	while (likely(skb->len)) {
827 		err = parse_hip(skb->data, skb->len, &hh);
828 		if (err) {
829 			if (netif_msg_rx_err(dev))
830 				netdev_err(dev->net, "Invalid HIP header %d\n",
831 					err);
832 			/* dev->net->stats.rx_errors incremented by caller */
833 			dev->net->stats.rx_length_errors++;
834 			return 0;
835 		}
836 
837 		/* Validate Extended HIP header */
838 		if (!hh.extmsgid.is_present
839 		    || hh.extmsgid.word != SIERRA_NET_HIP_EXT_IP_IN_ID) {
840 			if (netif_msg_rx_err(dev))
841 				netdev_err(dev->net, "HIP/ETH: Invalid pkt\n");
842 
843 			dev->net->stats.rx_frame_errors++;
844 			/* dev->net->stats.rx_errors incremented by caller */
845 			return 0;
846 		}
847 
848 		skb_pull(skb, hh.hdrlen);
849 
850 		/* We are going to accept this packet, prepare it.
851 		 * In case protocol is IPv6, keep it, otherwise force IPv4.
852 		 */
853 		skb_reset_mac_header(skb);
854 		if (eth_hdr(skb)->h_proto != cpu_to_be16(ETH_P_IPV6))
855 			eth_hdr(skb)->h_proto = cpu_to_be16(ETH_P_IP);
856 		eth_zero_addr(eth_hdr(skb)->h_source);
857 		memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
858 
859 		/* Last packet in batch handled by usbnet */
860 		if (hh.payload_len.word == skb->len)
861 			return 1;
862 
863 		new_skb = sierra_net_skb_clone(dev, skb, hh.payload_len.word);
864 		if (new_skb)
865 			usbnet_skb_return(dev, new_skb);
866 
867 	} /* while */
868 
869 	return 0;
870 }
871 
872 /* ---------------------------- Transmit data path ----------------------*/
873 static struct sk_buff *sierra_net_tx_fixup(struct usbnet *dev,
874 					   struct sk_buff *skb, gfp_t flags)
875 {
876 	struct sierra_net_data *priv = sierra_net_get_private(dev);
877 	u16 len;
878 	bool need_tail;
879 
880 	BUILD_BUG_ON(FIELD_SIZEOF(struct usbnet, data)
881 				< sizeof(struct cdc_state));
882 
883 	dev_dbg(&dev->udev->dev, "%s", __func__);
884 	if (priv->link_up && check_ethip_packet(skb, dev) && is_ip(skb)) {
885 		/* enough head room as is? */
886 		if (SIERRA_NET_HIP_EXT_HDR_LEN <= skb_headroom(skb)) {
887 			/* Save the Eth/IP length and set up HIP hdr */
888 			len = skb->len;
889 			skb_push(skb, SIERRA_NET_HIP_EXT_HDR_LEN);
890 			/* Handle ZLP issue */
891 			need_tail = ((len + SIERRA_NET_HIP_EXT_HDR_LEN)
892 				% dev->maxpacket == 0);
893 			if (need_tail) {
894 				if (unlikely(skb_tailroom(skb) == 0)) {
895 					netdev_err(dev->net, "tx_fixup:"
896 						"no room for packet\n");
897 					dev_kfree_skb_any(skb);
898 					return NULL;
899 				} else {
900 					skb->data[skb->len] = 0;
901 					__skb_put(skb, 1);
902 					len = len + 1;
903 				}
904 			}
905 			build_hip(skb->data, len, priv);
906 			return skb;
907 		} else {
908 			/*
909 			 * compensate in the future if necessary
910 			 */
911 			netdev_err(dev->net, "tx_fixup: no room for HIP\n");
912 		} /* headroom */
913 	}
914 
915 	if (!priv->link_up)
916 		dev->net->stats.tx_carrier_errors++;
917 
918 	/* tx_dropped incremented by usbnet */
919 
920 	/* filter the packet out, release it  */
921 	dev_kfree_skb_any(skb);
922 	return NULL;
923 }
924 
925 static const struct driver_info sierra_net_info_direct_ip = {
926 	.description = "Sierra Wireless USB-to-WWAN Modem",
927 	.flags = FLAG_WWAN | FLAG_SEND_ZLP,
928 	.bind = sierra_net_bind,
929 	.unbind = sierra_net_unbind,
930 	.status = sierra_net_status,
931 	.rx_fixup = sierra_net_rx_fixup,
932 	.tx_fixup = sierra_net_tx_fixup,
933 };
934 
935 static int
936 sierra_net_probe(struct usb_interface *udev, const struct usb_device_id *prod)
937 {
938 	int ret;
939 
940 	ret = usbnet_probe(udev, prod);
941 	if (ret == 0) {
942 		struct usbnet *dev = usb_get_intfdata(udev);
943 
944 		ret = usbnet_status_start(dev, GFP_KERNEL);
945 		if (ret == 0) {
946 			/* Interrupt URB now set up; initiate sync sequence */
947 			sierra_net_dosync(dev);
948 		}
949 	}
950 	return ret;
951 }
952 
953 #define DIRECT_IP_DEVICE(vend, prod) \
954 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 7), \
955 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
956 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 10), \
957 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
958 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 11), \
959 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}
960 
961 static const struct usb_device_id products[] = {
962 	DIRECT_IP_DEVICE(0x1199, 0x68A3), /* Sierra Wireless USB-to-WWAN modem */
963 	DIRECT_IP_DEVICE(0x0F3D, 0x68A3), /* AT&T Direct IP modem */
964 	DIRECT_IP_DEVICE(0x1199, 0x68AA), /* Sierra Wireless Direct IP LTE modem */
965 	DIRECT_IP_DEVICE(0x0F3D, 0x68AA), /* AT&T Direct IP LTE modem */
966 
967 	{}, /* last item */
968 };
969 MODULE_DEVICE_TABLE(usb, products);
970 
971 /* We are based on usbnet, so let it handle the USB driver specifics */
972 static struct usb_driver sierra_net_driver = {
973 	.name = "sierra_net",
974 	.id_table = products,
975 	.probe = sierra_net_probe,
976 	.disconnect = usbnet_disconnect,
977 	.suspend = usbnet_suspend,
978 	.resume = usbnet_resume,
979 	.no_dynamic_id = 1,
980 	.disable_hub_initiated_lpm = 1,
981 };
982 
983 module_usb_driver(sierra_net_driver);
984 
985 MODULE_AUTHOR(DRIVER_AUTHOR);
986 MODULE_DESCRIPTION(DRIVER_DESC);
987 MODULE_VERSION(DRIVER_VERSION);
988 MODULE_LICENSE("GPL");
989