xref: /linux/drivers/net/usb/sierra_net.c (revision 37744feebc086908fd89760650f458ab19071750)
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        = usbnet_get_stats64,
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 inline int sierra_net_is_valid_addrlen(u8 len)
358 {
359 	return len == sizeof(struct in_addr);
360 }
361 
362 static int sierra_net_parse_lsi(struct usbnet *dev, char *data, int datalen)
363 {
364 	struct lsi_umts *lsi = (struct lsi_umts *)data;
365 	u32 expected_length;
366 
367 	if (datalen < sizeof(struct lsi_umts_single)) {
368 		netdev_err(dev->net, "%s: Data length %d, exp >= %zu\n",
369 			   __func__, datalen, sizeof(struct lsi_umts_single));
370 		return -1;
371 	}
372 
373 	/* Validate the session state */
374 	if (lsi->session_state == SIERRA_NET_SESSION_IDLE) {
375 		netdev_err(dev->net, "Session idle, 0x%02x\n",
376 			   lsi->session_state);
377 		return 0;
378 	}
379 
380 	/* Validate the protocol  - only support UMTS for now */
381 	if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS) {
382 		struct lsi_umts_single *single = (struct lsi_umts_single *)lsi;
383 
384 		/* Validate the link type */
385 		if (single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV4 &&
386 		    single->link_type != SIERRA_NET_AS_LINK_TYPE_IPV6) {
387 			netdev_err(dev->net, "Link type unsupported: 0x%02x\n",
388 				   single->link_type);
389 			return -1;
390 		}
391 		expected_length = SIERRA_NET_LSI_UMTS_STATUS_LEN;
392 	} else if (lsi->protocol == SIERRA_NET_PROTOCOL_UMTS_DS) {
393 		expected_length = SIERRA_NET_LSI_UMTS_DS_STATUS_LEN;
394 	} else {
395 		netdev_err(dev->net, "Protocol unsupported, 0x%02x\n",
396 			   lsi->protocol);
397 		return -1;
398 	}
399 
400 	if (be16_to_cpu(lsi->length) != expected_length) {
401 		netdev_err(dev->net, "%s: LSI_UMTS_STATUS_LEN %d, exp %u\n",
402 			   __func__, be16_to_cpu(lsi->length), expected_length);
403 		return -1;
404 	}
405 
406 	/* Validate the coverage */
407 	if (lsi->coverage == SIERRA_NET_COVERAGE_NONE ||
408 	    lsi->coverage == SIERRA_NET_COVERAGE_NOPACKET) {
409 		netdev_err(dev->net, "No coverage, 0x%02x\n", lsi->coverage);
410 		return 0;
411 	}
412 
413 	/* Set link_sense true */
414 	return 1;
415 }
416 
417 static void sierra_net_handle_lsi(struct usbnet *dev, char *data,
418 		struct hip_hdr	*hh)
419 {
420 	struct sierra_net_data *priv = sierra_net_get_private(dev);
421 	int link_up;
422 
423 	link_up = sierra_net_parse_lsi(dev, data + hh->hdrlen,
424 					hh->payload_len.word);
425 	if (link_up < 0) {
426 		netdev_err(dev->net, "Invalid LSI\n");
427 		return;
428 	}
429 	if (link_up) {
430 		sierra_net_set_ctx_index(priv, hh->msgspecific.byte);
431 		priv->link_up = 1;
432 	} else {
433 		priv->link_up = 0;
434 	}
435 	usbnet_link_change(dev, link_up, 0);
436 }
437 
438 static void sierra_net_dosync(struct usbnet *dev)
439 {
440 	int status;
441 	struct sierra_net_data *priv = sierra_net_get_private(dev);
442 
443 	dev_dbg(&dev->udev->dev, "%s", __func__);
444 
445 	/* The SIERRA_NET_HIP_MSYNC_ID command appears to request that the
446 	 * firmware restart itself.  After restarting, the modem will respond
447 	 * with the SIERRA_NET_HIP_RESTART_ID indication.  The driver continues
448 	 * sending MSYNC commands every few seconds until it receives the
449 	 * RESTART event from the firmware
450 	 */
451 
452 	/* tell modem we are ready */
453 	status = sierra_net_send_sync(dev);
454 	if (status < 0)
455 		netdev_err(dev->net,
456 			"Send SYNC failed, status %d\n", status);
457 	status = sierra_net_send_sync(dev);
458 	if (status < 0)
459 		netdev_err(dev->net,
460 			"Send SYNC failed, status %d\n", status);
461 
462 	/* Now, start a timer and make sure we get the Restart Indication */
463 	priv->sync_timer.expires = jiffies + SIERRA_NET_SYNCDELAY;
464 	add_timer(&priv->sync_timer);
465 }
466 
467 static void sierra_net_kevent(struct work_struct *work)
468 {
469 	struct sierra_net_data *priv =
470 		container_of(work, struct sierra_net_data, sierra_net_kevent);
471 	struct usbnet *dev = priv->usbnet;
472 	int  len;
473 	int  err;
474 	u8  *buf;
475 	u8   ifnum;
476 
477 	if (test_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags)) {
478 		clear_bit(SIERRA_NET_EVENT_RESP_AVAIL, &priv->kevent_flags);
479 
480 		/* Query the modem for the LSI message */
481 		buf = kzalloc(SIERRA_NET_USBCTL_BUF_LEN, GFP_KERNEL);
482 		if (!buf)
483 			return;
484 
485 		ifnum = priv->ifnum;
486 		len = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0),
487 				USB_CDC_GET_ENCAPSULATED_RESPONSE,
488 				USB_DIR_IN|USB_TYPE_CLASS|USB_RECIP_INTERFACE,
489 				0, ifnum, buf, SIERRA_NET_USBCTL_BUF_LEN,
490 				USB_CTRL_SET_TIMEOUT);
491 
492 		if (len < 0) {
493 			netdev_err(dev->net,
494 				"usb_control_msg failed, status %d\n", len);
495 		} else {
496 			struct hip_hdr	hh;
497 
498 			dev_dbg(&dev->udev->dev, "%s: Received status message,"
499 				" %04x bytes", __func__, len);
500 
501 			err = parse_hip(buf, len, &hh);
502 			if (err) {
503 				netdev_err(dev->net, "%s: Bad packet,"
504 					" parse result %d\n", __func__, err);
505 				kfree(buf);
506 				return;
507 			}
508 
509 			/* Validate packet length */
510 			if (len != hh.hdrlen + hh.payload_len.word) {
511 				netdev_err(dev->net, "%s: Bad packet, received"
512 					" %d, expected %d\n",	__func__, len,
513 					hh.hdrlen + hh.payload_len.word);
514 				kfree(buf);
515 				return;
516 			}
517 
518 			/* Switch on received message types */
519 			switch (hh.msgid.byte) {
520 			case SIERRA_NET_HIP_LSI_UMTSID:
521 				dev_dbg(&dev->udev->dev, "LSI for ctx:%d",
522 					hh.msgspecific.byte);
523 				sierra_net_handle_lsi(dev, buf, &hh);
524 				break;
525 			case SIERRA_NET_HIP_RESTART_ID:
526 				dev_dbg(&dev->udev->dev, "Restart reported: %d,"
527 						" stopping sync timer",
528 						hh.msgspecific.byte);
529 				/* Got sync resp - stop timer & clear mask */
530 				del_timer_sync(&priv->sync_timer);
531 				clear_bit(SIERRA_NET_TIMER_EXPIRY,
532 					  &priv->kevent_flags);
533 				break;
534 			case SIERRA_NET_HIP_HSYNC_ID:
535 				dev_dbg(&dev->udev->dev, "SYNC received");
536 				err = sierra_net_send_sync(dev);
537 				if (err < 0)
538 					netdev_err(dev->net,
539 						"Send SYNC failed %d\n", err);
540 				break;
541 			case SIERRA_NET_HIP_EXTENDEDID:
542 				netdev_err(dev->net, "Unrecognized HIP msg, "
543 					"extmsgid 0x%04x\n", hh.extmsgid.word);
544 				break;
545 			case SIERRA_NET_HIP_RCGI:
546 				/* Ignored */
547 				break;
548 			default:
549 				netdev_err(dev->net, "Unrecognized HIP msg, "
550 					"msgid 0x%02x\n", hh.msgid.byte);
551 				break;
552 			}
553 		}
554 		kfree(buf);
555 	}
556 	/* The sync timer bit might be set */
557 	if (test_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags)) {
558 		clear_bit(SIERRA_NET_TIMER_EXPIRY, &priv->kevent_flags);
559 		dev_dbg(&dev->udev->dev, "Deferred sync timer expiry");
560 		sierra_net_dosync(priv->usbnet);
561 	}
562 
563 	if (priv->kevent_flags)
564 		dev_dbg(&dev->udev->dev, "sierra_net_kevent done, "
565 			"kevent_flags = 0x%lx", priv->kevent_flags);
566 }
567 
568 static void sierra_net_defer_kevent(struct usbnet *dev, int work)
569 {
570 	struct sierra_net_data *priv = sierra_net_get_private(dev);
571 
572 	set_bit(work, &priv->kevent_flags);
573 	schedule_work(&priv->sierra_net_kevent);
574 }
575 
576 /*
577  * Sync Retransmit Timer Handler. On expiry, kick the work queue
578  */
579 static void sierra_sync_timer(struct timer_list *t)
580 {
581 	struct sierra_net_data *priv = from_timer(priv, t, sync_timer);
582 	struct usbnet *dev = priv->usbnet;
583 
584 	dev_dbg(&dev->udev->dev, "%s", __func__);
585 	/* Kick the tasklet */
586 	sierra_net_defer_kevent(dev, SIERRA_NET_TIMER_EXPIRY);
587 }
588 
589 static void sierra_net_status(struct usbnet *dev, struct urb *urb)
590 {
591 	struct usb_cdc_notification *event;
592 
593 	dev_dbg(&dev->udev->dev, "%s", __func__);
594 
595 	if (urb->actual_length < sizeof *event)
596 		return;
597 
598 	/* Add cases to handle other standard notifications. */
599 	event = urb->transfer_buffer;
600 	switch (event->bNotificationType) {
601 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
602 	case USB_CDC_NOTIFY_SPEED_CHANGE:
603 		/* USB 305 sends those */
604 		break;
605 	case USB_CDC_NOTIFY_RESPONSE_AVAILABLE:
606 		sierra_net_defer_kevent(dev, SIERRA_NET_EVENT_RESP_AVAIL);
607 		break;
608 	default:
609 		netdev_err(dev->net, ": unexpected notification %02x!\n",
610 				event->bNotificationType);
611 		break;
612 	}
613 }
614 
615 static void sierra_net_get_drvinfo(struct net_device *net,
616 		struct ethtool_drvinfo *info)
617 {
618 	/* Inherit standard device info */
619 	usbnet_get_drvinfo(net, info);
620 	strlcpy(info->driver, driver_name, sizeof(info->driver));
621 	strlcpy(info->version, DRIVER_VERSION, sizeof(info->version));
622 }
623 
624 static u32 sierra_net_get_link(struct net_device *net)
625 {
626 	struct usbnet *dev = netdev_priv(net);
627 	/* Report link is down whenever the interface is down */
628 	return sierra_net_get_private(dev)->link_up && netif_running(net);
629 }
630 
631 static const struct ethtool_ops sierra_net_ethtool_ops = {
632 	.get_drvinfo = sierra_net_get_drvinfo,
633 	.get_link = sierra_net_get_link,
634 	.get_msglevel = usbnet_get_msglevel,
635 	.set_msglevel = usbnet_set_msglevel,
636 	.nway_reset = usbnet_nway_reset,
637 	.get_link_ksettings = usbnet_get_link_ksettings,
638 	.set_link_ksettings = usbnet_set_link_ksettings,
639 };
640 
641 static int sierra_net_get_fw_attr(struct usbnet *dev, u16 *datap)
642 {
643 	int result = 0;
644 	__le16 attrdata;
645 
646 	result = usbnet_read_cmd(dev,
647 				/* _u8 vendor specific request */
648 				SWI_USB_REQUEST_GET_FW_ATTR,
649 				USB_DIR_IN | USB_TYPE_VENDOR,	/* __u8 request type */
650 				0x0000,		/* __u16 value not used */
651 				0x0000,		/* __u16 index  not used */
652 				&attrdata,	/* char *data */
653 				sizeof(attrdata)	/* __u16 size */
654 				);
655 
656 	if (result < 0)
657 		return -EIO;
658 
659 	*datap = le16_to_cpu(attrdata);
660 	return result;
661 }
662 
663 /*
664  * collects the bulk endpoints, the status endpoint.
665  */
666 static int sierra_net_bind(struct usbnet *dev, struct usb_interface *intf)
667 {
668 	u8	ifacenum;
669 	u8	numendpoints;
670 	u16	fwattr = 0;
671 	int	status;
672 	struct sierra_net_data *priv;
673 	static const u8 sync_tmplate[sizeof(priv->sync_msg)] = {
674 		0x00, 0x00, SIERRA_NET_HIP_MSYNC_ID, 0x00};
675 	static const u8 shdwn_tmplate[sizeof(priv->shdwn_msg)] = {
676 		0x00, 0x00, SIERRA_NET_HIP_SHUTD_ID, 0x00};
677 
678 	dev_dbg(&dev->udev->dev, "%s", __func__);
679 
680 	ifacenum = intf->cur_altsetting->desc.bInterfaceNumber;
681 	numendpoints = intf->cur_altsetting->desc.bNumEndpoints;
682 	/* We have three endpoints, bulk in and out, and a status */
683 	if (numendpoints != 3) {
684 		dev_err(&dev->udev->dev, "Expected 3 endpoints, found: %d",
685 			numendpoints);
686 		return -ENODEV;
687 	}
688 	/* Status endpoint set in usbnet_get_endpoints() */
689 	dev->status = NULL;
690 	status = usbnet_get_endpoints(dev, intf);
691 	if (status < 0) {
692 		dev_err(&dev->udev->dev, "Error in usbnet_get_endpoints (%d)",
693 			status);
694 		return -ENODEV;
695 	}
696 	/* Initialize sierra private data */
697 	priv = kzalloc(sizeof *priv, GFP_KERNEL);
698 	if (!priv)
699 		return -ENOMEM;
700 
701 	priv->usbnet = dev;
702 	priv->ifnum = ifacenum;
703 	dev->net->netdev_ops = &sierra_net_device_ops;
704 
705 	/* change MAC addr to include, ifacenum, and to be unique */
706 	dev->net->dev_addr[ETH_ALEN-2] = atomic_inc_return(&iface_counter);
707 	dev->net->dev_addr[ETH_ALEN-1] = ifacenum;
708 
709 	/* prepare shutdown message template */
710 	memcpy(priv->shdwn_msg, shdwn_tmplate, sizeof(priv->shdwn_msg));
711 	/* set context index initially to 0 - prepares tx hdr template */
712 	sierra_net_set_ctx_index(priv, 0);
713 
714 	/* prepare sync message template */
715 	memcpy(priv->sync_msg, sync_tmplate, sizeof(priv->sync_msg));
716 
717 	/* decrease the rx_urb_size and max_tx_size to 4k on USB 1.1 */
718 	dev->rx_urb_size  = SIERRA_NET_RX_URB_SIZE;
719 	if (dev->udev->speed != USB_SPEED_HIGH)
720 		dev->rx_urb_size  = min_t(size_t, 4096, SIERRA_NET_RX_URB_SIZE);
721 
722 	dev->net->hard_header_len += SIERRA_NET_HIP_EXT_HDR_LEN;
723 	dev->hard_mtu = dev->net->mtu + dev->net->hard_header_len;
724 	dev->net->max_mtu = SIERRA_NET_MAX_SUPPORTED_MTU;
725 
726 	/* Set up the netdev */
727 	dev->net->flags |= IFF_NOARP;
728 	dev->net->ethtool_ops = &sierra_net_ethtool_ops;
729 	netif_carrier_off(dev->net);
730 
731 	sierra_net_set_private(dev, priv);
732 
733 	priv->kevent_flags = 0;
734 
735 	/* Use the shared workqueue */
736 	INIT_WORK(&priv->sierra_net_kevent, sierra_net_kevent);
737 
738 	/* Only need to do this once */
739 	timer_setup(&priv->sync_timer, sierra_sync_timer, 0);
740 
741 	/* verify fw attributes */
742 	status = sierra_net_get_fw_attr(dev, &fwattr);
743 	dev_dbg(&dev->udev->dev, "Fw attr: %x\n", fwattr);
744 
745 	/* test whether firmware supports DHCP */
746 	if (!(status == sizeof(fwattr) && (fwattr & SWI_GET_FW_ATTR_MASK))) {
747 		/* found incompatible firmware version */
748 		dev_err(&dev->udev->dev, "Incompatible driver and firmware"
749 			" versions\n");
750 		kfree(priv);
751 		return -ENODEV;
752 	}
753 
754 	return 0;
755 }
756 
757 static void sierra_net_unbind(struct usbnet *dev, struct usb_interface *intf)
758 {
759 	int status;
760 	struct sierra_net_data *priv = sierra_net_get_private(dev);
761 
762 	dev_dbg(&dev->udev->dev, "%s", __func__);
763 
764 	/* kill the timer and work */
765 	del_timer_sync(&priv->sync_timer);
766 	cancel_work_sync(&priv->sierra_net_kevent);
767 
768 	/* tell modem we are going away */
769 	status = sierra_net_send_cmd(dev, priv->shdwn_msg,
770 			sizeof(priv->shdwn_msg), "Shutdown");
771 	if (status < 0)
772 		netdev_err(dev->net,
773 			"usb_control_msg failed, status %d\n", status);
774 
775 	usbnet_status_stop(dev);
776 
777 	sierra_net_set_private(dev, NULL);
778 	kfree(priv);
779 }
780 
781 static struct sk_buff *sierra_net_skb_clone(struct usbnet *dev,
782 		struct sk_buff *skb, int len)
783 {
784 	struct sk_buff *new_skb;
785 
786 	/* clone skb */
787 	new_skb = skb_clone(skb, GFP_ATOMIC);
788 
789 	/* remove len bytes from original */
790 	skb_pull(skb, len);
791 
792 	/* trim next packet to it's length */
793 	if (new_skb) {
794 		skb_trim(new_skb, len);
795 	} else {
796 		if (netif_msg_rx_err(dev))
797 			netdev_err(dev->net, "failed to get skb\n");
798 		dev->net->stats.rx_dropped++;
799 	}
800 
801 	return new_skb;
802 }
803 
804 /* ---------------------------- Receive data path ----------------------*/
805 static int sierra_net_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
806 {
807 	int err;
808 	struct hip_hdr  hh;
809 	struct sk_buff *new_skb;
810 
811 	dev_dbg(&dev->udev->dev, "%s", __func__);
812 
813 	/* could contain multiple packets */
814 	while (likely(skb->len)) {
815 		err = parse_hip(skb->data, skb->len, &hh);
816 		if (err) {
817 			if (netif_msg_rx_err(dev))
818 				netdev_err(dev->net, "Invalid HIP header %d\n",
819 					err);
820 			/* dev->net->stats.rx_errors incremented by caller */
821 			dev->net->stats.rx_length_errors++;
822 			return 0;
823 		}
824 
825 		/* Validate Extended HIP header */
826 		if (!hh.extmsgid.is_present
827 		    || hh.extmsgid.word != SIERRA_NET_HIP_EXT_IP_IN_ID) {
828 			if (netif_msg_rx_err(dev))
829 				netdev_err(dev->net, "HIP/ETH: Invalid pkt\n");
830 
831 			dev->net->stats.rx_frame_errors++;
832 			/* dev->net->stats.rx_errors incremented by caller */
833 			return 0;
834 		}
835 
836 		skb_pull(skb, hh.hdrlen);
837 
838 		/* We are going to accept this packet, prepare it.
839 		 * In case protocol is IPv6, keep it, otherwise force IPv4.
840 		 */
841 		skb_reset_mac_header(skb);
842 		if (eth_hdr(skb)->h_proto != cpu_to_be16(ETH_P_IPV6))
843 			eth_hdr(skb)->h_proto = cpu_to_be16(ETH_P_IP);
844 		eth_zero_addr(eth_hdr(skb)->h_source);
845 		memcpy(eth_hdr(skb)->h_dest, dev->net->dev_addr, ETH_ALEN);
846 
847 		/* Last packet in batch handled by usbnet */
848 		if (hh.payload_len.word == skb->len)
849 			return 1;
850 
851 		new_skb = sierra_net_skb_clone(dev, skb, hh.payload_len.word);
852 		if (new_skb)
853 			usbnet_skb_return(dev, new_skb);
854 
855 	} /* while */
856 
857 	return 0;
858 }
859 
860 /* ---------------------------- Transmit data path ----------------------*/
861 static struct sk_buff *sierra_net_tx_fixup(struct usbnet *dev,
862 					   struct sk_buff *skb, gfp_t flags)
863 {
864 	struct sierra_net_data *priv = sierra_net_get_private(dev);
865 	u16 len;
866 	bool need_tail;
867 
868 	BUILD_BUG_ON(sizeof_field(struct usbnet, data)
869 				< sizeof(struct cdc_state));
870 
871 	dev_dbg(&dev->udev->dev, "%s", __func__);
872 	if (priv->link_up && check_ethip_packet(skb, dev) && is_ip(skb)) {
873 		/* enough head room as is? */
874 		if (SIERRA_NET_HIP_EXT_HDR_LEN <= skb_headroom(skb)) {
875 			/* Save the Eth/IP length and set up HIP hdr */
876 			len = skb->len;
877 			skb_push(skb, SIERRA_NET_HIP_EXT_HDR_LEN);
878 			/* Handle ZLP issue */
879 			need_tail = ((len + SIERRA_NET_HIP_EXT_HDR_LEN)
880 				% dev->maxpacket == 0);
881 			if (need_tail) {
882 				if (unlikely(skb_tailroom(skb) == 0)) {
883 					netdev_err(dev->net, "tx_fixup:"
884 						"no room for packet\n");
885 					dev_kfree_skb_any(skb);
886 					return NULL;
887 				} else {
888 					skb->data[skb->len] = 0;
889 					__skb_put(skb, 1);
890 					len = len + 1;
891 				}
892 			}
893 			build_hip(skb->data, len, priv);
894 			return skb;
895 		} else {
896 			/*
897 			 * compensate in the future if necessary
898 			 */
899 			netdev_err(dev->net, "tx_fixup: no room for HIP\n");
900 		} /* headroom */
901 	}
902 
903 	if (!priv->link_up)
904 		dev->net->stats.tx_carrier_errors++;
905 
906 	/* tx_dropped incremented by usbnet */
907 
908 	/* filter the packet out, release it  */
909 	dev_kfree_skb_any(skb);
910 	return NULL;
911 }
912 
913 static const struct driver_info sierra_net_info_direct_ip = {
914 	.description = "Sierra Wireless USB-to-WWAN Modem",
915 	.flags = FLAG_WWAN | FLAG_SEND_ZLP,
916 	.bind = sierra_net_bind,
917 	.unbind = sierra_net_unbind,
918 	.status = sierra_net_status,
919 	.rx_fixup = sierra_net_rx_fixup,
920 	.tx_fixup = sierra_net_tx_fixup,
921 };
922 
923 static int
924 sierra_net_probe(struct usb_interface *udev, const struct usb_device_id *prod)
925 {
926 	int ret;
927 
928 	ret = usbnet_probe(udev, prod);
929 	if (ret == 0) {
930 		struct usbnet *dev = usb_get_intfdata(udev);
931 
932 		ret = usbnet_status_start(dev, GFP_KERNEL);
933 		if (ret == 0) {
934 			/* Interrupt URB now set up; initiate sync sequence */
935 			sierra_net_dosync(dev);
936 		}
937 	}
938 	return ret;
939 }
940 
941 #define DIRECT_IP_DEVICE(vend, prod) \
942 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 7), \
943 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
944 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 10), \
945 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}, \
946 	{USB_DEVICE_INTERFACE_NUMBER(vend, prod, 11), \
947 	.driver_info = (unsigned long)&sierra_net_info_direct_ip}
948 
949 static const struct usb_device_id products[] = {
950 	DIRECT_IP_DEVICE(0x1199, 0x68A3), /* Sierra Wireless USB-to-WWAN modem */
951 	DIRECT_IP_DEVICE(0x0F3D, 0x68A3), /* AT&T Direct IP modem */
952 	DIRECT_IP_DEVICE(0x1199, 0x68AA), /* Sierra Wireless Direct IP LTE modem */
953 	DIRECT_IP_DEVICE(0x0F3D, 0x68AA), /* AT&T Direct IP LTE modem */
954 
955 	{}, /* last item */
956 };
957 MODULE_DEVICE_TABLE(usb, products);
958 
959 /* We are based on usbnet, so let it handle the USB driver specifics */
960 static struct usb_driver sierra_net_driver = {
961 	.name = "sierra_net",
962 	.id_table = products,
963 	.probe = sierra_net_probe,
964 	.disconnect = usbnet_disconnect,
965 	.suspend = usbnet_suspend,
966 	.resume = usbnet_resume,
967 	.no_dynamic_id = 1,
968 	.disable_hub_initiated_lpm = 1,
969 };
970 
971 module_usb_driver(sierra_net_driver);
972 
973 MODULE_AUTHOR(DRIVER_AUTHOR);
974 MODULE_DESCRIPTION(DRIVER_DESC);
975 MODULE_VERSION(DRIVER_VERSION);
976 MODULE_LICENSE("GPL");
977