xref: /linux/drivers/staging/gdm724x/gdm_lte.c (revision e2be04c7f9958dde770eeb8b30e829ca969b37bb)
1 /*
2  * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
3  *
4  * This software is licensed under the terms of the GNU General Public
5  * License version 2, as published by the Free Software Foundation, and
6  * may be copied, distributed, and modified under those terms.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11  * GNU General Public License for more details.
12  */
13 
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 
16 #include <linux/etherdevice.h>
17 #include <linux/ip.h>
18 #include <linux/ipv6.h>
19 #include <linux/udp.h>
20 #include <linux/in.h>
21 #include <linux/if_arp.h>
22 #include <linux/if_ether.h>
23 #include <linux/if_vlan.h>
24 #include <linux/in6.h>
25 #include <linux/tcp.h>
26 #include <linux/icmp.h>
27 #include <linux/icmpv6.h>
28 #include <linux/uaccess.h>
29 #include <net/ndisc.h>
30 
31 #include "gdm_lte.h"
32 #include "netlink_k.h"
33 #include "hci.h"
34 #include "hci_packet.h"
35 #include "gdm_endian.h"
36 
37 /*
38  * Netlink protocol number
39  */
40 #define NETLINK_LTE 30
41 
42 /*
43  * Default MTU Size
44  */
45 #define DEFAULT_MTU_SIZE 1500
46 
47 #define IP_VERSION_4	4
48 #define IP_VERSION_6	6
49 
50 static struct {
51 	int ref_cnt;
52 	struct sock *sock;
53 } lte_event;
54 
55 static struct device_type wwan_type = {
56 	.name   = "wwan",
57 };
58 
59 static int gdm_lte_open(struct net_device *dev)
60 {
61 	netif_start_queue(dev);
62 	return 0;
63 }
64 
65 static int gdm_lte_close(struct net_device *dev)
66 {
67 	netif_stop_queue(dev);
68 	return 0;
69 }
70 
71 static int gdm_lte_set_config(struct net_device *dev, struct ifmap *map)
72 {
73 	if (dev->flags & IFF_UP)
74 		return -EBUSY;
75 	return 0;
76 }
77 
78 static void tx_complete(void *arg)
79 {
80 	struct nic *nic = arg;
81 
82 	if (netif_queue_stopped(nic->netdev))
83 		netif_wake_queue(nic->netdev);
84 }
85 
86 static int gdm_lte_rx(struct sk_buff *skb, struct nic *nic, int nic_type)
87 {
88 	int ret;
89 
90 	ret = netif_rx_ni(skb);
91 	if (ret == NET_RX_DROP) {
92 		nic->stats.rx_dropped++;
93 	} else {
94 		nic->stats.rx_packets++;
95 		nic->stats.rx_bytes += skb->len + ETH_HLEN;
96 	}
97 
98 	return 0;
99 }
100 
101 static int gdm_lte_emulate_arp(struct sk_buff *skb_in, u32 nic_type)
102 {
103 	struct nic *nic = netdev_priv(skb_in->dev);
104 	struct sk_buff *skb_out;
105 	struct ethhdr eth;
106 	struct vlan_ethhdr vlan_eth;
107 	struct arphdr *arp_in;
108 	struct arphdr *arp_out;
109 	struct arpdata {
110 		u8 ar_sha[ETH_ALEN];
111 		u8 ar_sip[4];
112 		u8 ar_tha[ETH_ALEN];
113 		u8 ar_tip[4];
114 	};
115 	struct arpdata *arp_data_in;
116 	struct arpdata *arp_data_out;
117 	u8 arp_temp[60];
118 	void *mac_header_data;
119 	u32 mac_header_len;
120 
121 	/* Format the mac header so that it can be put to skb */
122 	if (ntohs(((struct ethhdr *)skb_in->data)->h_proto) == ETH_P_8021Q) {
123 		memcpy(&vlan_eth, skb_in->data, sizeof(struct vlan_ethhdr));
124 		mac_header_data = &vlan_eth;
125 		mac_header_len = VLAN_ETH_HLEN;
126 	} else {
127 		memcpy(&eth, skb_in->data, sizeof(struct ethhdr));
128 		mac_header_data = &eth;
129 		mac_header_len = ETH_HLEN;
130 	}
131 
132 	/* Get the pointer of the original request */
133 	arp_in = (struct arphdr *)(skb_in->data + mac_header_len);
134 	arp_data_in = (struct arpdata *)(skb_in->data + mac_header_len +
135 					sizeof(struct arphdr));
136 
137 	/* Get the pointer of the outgoing response */
138 	arp_out = (struct arphdr *)arp_temp;
139 	arp_data_out = (struct arpdata *)(arp_temp + sizeof(struct arphdr));
140 
141 	/* Copy the arp header */
142 	memcpy(arp_out, arp_in, sizeof(struct arphdr));
143 	arp_out->ar_op = htons(ARPOP_REPLY);
144 
145 	/* Copy the arp payload: based on 2 bytes of mac and fill the IP */
146 	arp_data_out->ar_sha[0] = arp_data_in->ar_sha[0];
147 	arp_data_out->ar_sha[1] = arp_data_in->ar_sha[1];
148 	memcpy(&arp_data_out->ar_sha[2], &arp_data_in->ar_tip[0], 4);
149 	memcpy(&arp_data_out->ar_sip[0], &arp_data_in->ar_tip[0], 4);
150 	memcpy(&arp_data_out->ar_tha[0], &arp_data_in->ar_sha[0], 6);
151 	memcpy(&arp_data_out->ar_tip[0], &arp_data_in->ar_sip[0], 4);
152 
153 	/* Fill the destination mac with source mac of the received packet */
154 	memcpy(mac_header_data, mac_header_data + ETH_ALEN, ETH_ALEN);
155 	/* Fill the source mac with nic's source mac */
156 	memcpy(mac_header_data + ETH_ALEN, nic->src_mac_addr, ETH_ALEN);
157 
158 	/* Alloc skb and reserve align */
159 	skb_out = dev_alloc_skb(skb_in->len);
160 	if (!skb_out)
161 		return -ENOMEM;
162 	skb_reserve(skb_out, NET_IP_ALIGN);
163 
164 	skb_put_data(skb_out, mac_header_data, mac_header_len);
165 	skb_put_data(skb_out, arp_out, sizeof(struct arphdr));
166 	skb_put_data(skb_out, arp_data_out, sizeof(struct arpdata));
167 
168 	skb_out->protocol = ((struct ethhdr *)mac_header_data)->h_proto;
169 	skb_out->dev = skb_in->dev;
170 	skb_reset_mac_header(skb_out);
171 	skb_pull(skb_out, ETH_HLEN);
172 
173 	gdm_lte_rx(skb_out, nic, nic_type);
174 
175 	return 0;
176 }
177 
178 static __sum16 icmp6_checksum(struct ipv6hdr *ipv6, u16 *ptr, int len)
179 {
180 	unsigned short *w = ptr;
181 	__wsum sum = 0;
182 	int i;
183 
184 	union {
185 		struct {
186 			u8 ph_src[16];
187 			u8 ph_dst[16];
188 			u32 ph_len;
189 			u8 ph_zero[3];
190 			u8 ph_nxt;
191 		} ph __packed;
192 		u16 pa[20];
193 	} pseudo_header;
194 
195 	memset(&pseudo_header, 0, sizeof(pseudo_header));
196 	memcpy(&pseudo_header.ph.ph_src, &ipv6->saddr.in6_u.u6_addr8, 16);
197 	memcpy(&pseudo_header.ph.ph_dst, &ipv6->daddr.in6_u.u6_addr8, 16);
198 	pseudo_header.ph.ph_len = be16_to_cpu(ipv6->payload_len);
199 	pseudo_header.ph.ph_nxt = ipv6->nexthdr;
200 
201 	w = (u16 *)&pseudo_header;
202 	for (i = 0; i < ARRAY_SIZE(pseudo_header.pa); i++)
203 		sum = csum_add(sum, csum_unfold(
204 					(__force __sum16)pseudo_header.pa[i]));
205 
206 	w = ptr;
207 	while (len > 1) {
208 		sum = csum_add(sum, csum_unfold((__force __sum16)*w++));
209 		len -= 2;
210 	}
211 
212 	return csum_fold(sum);
213 }
214 
215 static int gdm_lte_emulate_ndp(struct sk_buff *skb_in, u32 nic_type)
216 {
217 	struct nic *nic = netdev_priv(skb_in->dev);
218 	struct sk_buff *skb_out;
219 	struct ethhdr eth;
220 	struct vlan_ethhdr vlan_eth;
221 	struct neighbour_advertisement {
222 		u8 target_address[16];
223 		u8 type;
224 		u8 length;
225 		u8 link_layer_address[6];
226 	};
227 	struct neighbour_advertisement na;
228 	struct neighbour_solicitation {
229 		u8 target_address[16];
230 	};
231 	struct neighbour_solicitation *ns;
232 	struct ipv6hdr *ipv6_in;
233 	struct ipv6hdr ipv6_out;
234 	struct icmp6hdr *icmp6_in;
235 	struct icmp6hdr icmp6_out;
236 
237 	void *mac_header_data;
238 	u32 mac_header_len;
239 
240 	/* Format the mac header so that it can be put to skb */
241 	if (ntohs(((struct ethhdr *)skb_in->data)->h_proto) == ETH_P_8021Q) {
242 		memcpy(&vlan_eth, skb_in->data, sizeof(struct vlan_ethhdr));
243 		if (ntohs(vlan_eth.h_vlan_encapsulated_proto) != ETH_P_IPV6)
244 			return -1;
245 		mac_header_data = &vlan_eth;
246 		mac_header_len = VLAN_ETH_HLEN;
247 	} else {
248 		memcpy(&eth, skb_in->data, sizeof(struct ethhdr));
249 		if (ntohs(eth.h_proto) != ETH_P_IPV6)
250 			return -1;
251 		mac_header_data = &eth;
252 		mac_header_len = ETH_HLEN;
253 	}
254 
255 	/* Check if this is IPv6 ICMP packet */
256 	ipv6_in = (struct ipv6hdr *)(skb_in->data + mac_header_len);
257 	if (ipv6_in->version != 6 || ipv6_in->nexthdr != IPPROTO_ICMPV6)
258 		return -1;
259 
260 	/* Check if this is NDP packet */
261 	icmp6_in = (struct icmp6hdr *)(skb_in->data + mac_header_len +
262 					sizeof(struct ipv6hdr));
263 	if (icmp6_in->icmp6_type == NDISC_ROUTER_SOLICITATION) { /* Check RS */
264 		return -1;
265 	} else if (icmp6_in->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) {
266 		/* Check NS */
267 		u8 icmp_na[sizeof(struct icmp6hdr) +
268 			sizeof(struct neighbour_advertisement)];
269 		u8 zero_addr8[16] = {0,};
270 
271 		if (memcmp(ipv6_in->saddr.in6_u.u6_addr8, zero_addr8, 16) == 0)
272 			/* Duplicate Address Detection: Source IP is all zero */
273 			return 0;
274 
275 		icmp6_out.icmp6_type = NDISC_NEIGHBOUR_ADVERTISEMENT;
276 		icmp6_out.icmp6_code = 0;
277 		icmp6_out.icmp6_cksum = 0;
278 		/* R=0, S=1, O=1 */
279 		icmp6_out.icmp6_dataun.un_data32[0] = htonl(0x60000000);
280 
281 		ns = (struct neighbour_solicitation *)
282 			(skb_in->data + mac_header_len +
283 			 sizeof(struct ipv6hdr) + sizeof(struct icmp6hdr));
284 		memcpy(&na.target_address, ns->target_address, 16);
285 		na.type = 0x02;
286 		na.length = 1;
287 		na.link_layer_address[0] = 0x00;
288 		na.link_layer_address[1] = 0x0a;
289 		na.link_layer_address[2] = 0x3b;
290 		na.link_layer_address[3] = 0xaf;
291 		na.link_layer_address[4] = 0x63;
292 		na.link_layer_address[5] = 0xc7;
293 
294 		memcpy(&ipv6_out, ipv6_in, sizeof(struct ipv6hdr));
295 		memcpy(ipv6_out.saddr.in6_u.u6_addr8, &na.target_address, 16);
296 		memcpy(ipv6_out.daddr.in6_u.u6_addr8,
297 		       ipv6_in->saddr.in6_u.u6_addr8, 16);
298 		ipv6_out.payload_len = htons(sizeof(struct icmp6hdr) +
299 				sizeof(struct neighbour_advertisement));
300 
301 		memcpy(icmp_na, &icmp6_out, sizeof(struct icmp6hdr));
302 		memcpy(icmp_na + sizeof(struct icmp6hdr), &na,
303 		       sizeof(struct neighbour_advertisement));
304 
305 		icmp6_out.icmp6_cksum = icmp6_checksum(&ipv6_out,
306 					(u16 *)icmp_na, sizeof(icmp_na));
307 	} else {
308 		return -1;
309 	}
310 
311 	/* Fill the destination mac with source mac of the received packet */
312 	memcpy(mac_header_data, mac_header_data + ETH_ALEN, ETH_ALEN);
313 	/* Fill the source mac with nic's source mac */
314 	memcpy(mac_header_data + ETH_ALEN, nic->src_mac_addr, ETH_ALEN);
315 
316 	/* Alloc skb and reserve align */
317 	skb_out = dev_alloc_skb(skb_in->len);
318 	if (!skb_out)
319 		return -ENOMEM;
320 	skb_reserve(skb_out, NET_IP_ALIGN);
321 
322 	skb_put_data(skb_out, mac_header_data, mac_header_len);
323 	skb_put_data(skb_out, &ipv6_out, sizeof(struct ipv6hdr));
324 	skb_put_data(skb_out, &icmp6_out, sizeof(struct icmp6hdr));
325 	skb_put_data(skb_out, &na, sizeof(struct neighbour_advertisement));
326 
327 	skb_out->protocol = ((struct ethhdr *)mac_header_data)->h_proto;
328 	skb_out->dev = skb_in->dev;
329 	skb_reset_mac_header(skb_out);
330 	skb_pull(skb_out, ETH_HLEN);
331 
332 	gdm_lte_rx(skb_out, nic, nic_type);
333 
334 	return 0;
335 }
336 
337 static s32 gdm_lte_tx_nic_type(struct net_device *dev, struct sk_buff *skb)
338 {
339 	struct nic *nic = netdev_priv(dev);
340 	struct ethhdr *eth;
341 	struct vlan_ethhdr *vlan_eth;
342 	struct iphdr *ip;
343 	struct ipv6hdr *ipv6;
344 	int mac_proto;
345 	void *network_data;
346 	u32 nic_type;
347 
348 	/* NIC TYPE is based on the nic_id of this net_device */
349 	nic_type = 0x00000010 | nic->nic_id;
350 
351 	/* Get ethernet protocol */
352 	eth = (struct ethhdr *)skb->data;
353 	if (ntohs(eth->h_proto) == ETH_P_8021Q) {
354 		vlan_eth = (struct vlan_ethhdr *)skb->data;
355 		mac_proto = ntohs(vlan_eth->h_vlan_encapsulated_proto);
356 		network_data = skb->data + VLAN_ETH_HLEN;
357 		nic_type |= NIC_TYPE_F_VLAN;
358 	} else {
359 		mac_proto = ntohs(eth->h_proto);
360 		network_data = skb->data + ETH_HLEN;
361 	}
362 
363 	/* Process packet for nic type */
364 	switch (mac_proto) {
365 	case ETH_P_ARP:
366 		nic_type |= NIC_TYPE_ARP;
367 		break;
368 	case ETH_P_IP:
369 		nic_type |= NIC_TYPE_F_IPV4;
370 		ip = network_data;
371 
372 		/* Check DHCPv4 */
373 		if (ip->protocol == IPPROTO_UDP) {
374 			struct udphdr *udp =
375 					network_data + sizeof(struct iphdr);
376 			if (ntohs(udp->dest) == 67 || ntohs(udp->dest) == 68)
377 				nic_type |= NIC_TYPE_F_DHCP;
378 		}
379 		break;
380 	case ETH_P_IPV6:
381 		nic_type |= NIC_TYPE_F_IPV6;
382 		ipv6 = network_data;
383 
384 		if (ipv6->nexthdr == IPPROTO_ICMPV6) /* Check NDP request */ {
385 			struct icmp6hdr *icmp6 =
386 					network_data + sizeof(struct ipv6hdr);
387 			if (icmp6->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION)
388 				nic_type |= NIC_TYPE_ICMPV6;
389 		} else if (ipv6->nexthdr == IPPROTO_UDP) /* Check DHCPv6 */ {
390 			struct udphdr *udp =
391 					network_data + sizeof(struct ipv6hdr);
392 			if (ntohs(udp->dest) == 546 || ntohs(udp->dest) == 547)
393 				nic_type |= NIC_TYPE_F_DHCP;
394 		}
395 		break;
396 	default:
397 		break;
398 	}
399 
400 	return nic_type;
401 }
402 
403 static int gdm_lte_tx(struct sk_buff *skb, struct net_device *dev)
404 {
405 	struct nic *nic = netdev_priv(dev);
406 	u32 nic_type;
407 	void *data_buf;
408 	int data_len;
409 	int idx;
410 	int ret = 0;
411 
412 	nic_type = gdm_lte_tx_nic_type(dev, skb);
413 	if (nic_type == 0) {
414 		netdev_err(dev, "tx - invalid nic_type\n");
415 		return -1;
416 	}
417 
418 	if (nic_type & NIC_TYPE_ARP) {
419 		if (gdm_lte_emulate_arp(skb, nic_type) == 0) {
420 			dev_kfree_skb(skb);
421 			return 0;
422 		}
423 	}
424 
425 	if (nic_type & NIC_TYPE_ICMPV6) {
426 		if (gdm_lte_emulate_ndp(skb, nic_type) == 0) {
427 			dev_kfree_skb(skb);
428 			return 0;
429 		}
430 	}
431 
432 	/*
433 	 * Need byte shift (that is, remove VLAN tag) if there is one
434 	 * For the case of ARP, this breaks the offset as vlan_ethhdr+4
435 	 * is treated as ethhdr	However, it shouldn't be a problem as
436 	 * the response starts from arp_hdr and ethhdr is created by this
437 	 * driver based on the NIC mac
438 	 */
439 	if (nic_type & NIC_TYPE_F_VLAN) {
440 		struct vlan_ethhdr *vlan_eth = (struct vlan_ethhdr *)skb->data;
441 
442 		nic->vlan_id = ntohs(vlan_eth->h_vlan_TCI) & VLAN_VID_MASK;
443 		data_buf = skb->data + (VLAN_ETH_HLEN - ETH_HLEN);
444 		data_len = skb->len - (VLAN_ETH_HLEN - ETH_HLEN);
445 	} else {
446 		nic->vlan_id = 0;
447 		data_buf = skb->data;
448 		data_len = skb->len;
449 	}
450 
451 	/* If it is a ICMPV6 packet, clear all the other bits :
452 	 * for backward compatibility with the firmware
453 	 */
454 	if (nic_type & NIC_TYPE_ICMPV6)
455 		nic_type = NIC_TYPE_ICMPV6;
456 
457 	/* If it is not a dhcp packet, clear all the flag bits :
458 	 * original NIC, otherwise the special flag (IPVX | DHCP)
459 	 */
460 	if (!(nic_type & NIC_TYPE_F_DHCP))
461 		nic_type &= NIC_TYPE_MASK;
462 
463 	ret = sscanf(dev->name, "lte%d", &idx);
464 	if (ret != 1) {
465 		dev_kfree_skb(skb);
466 		return -EINVAL;
467 	}
468 
469 	ret = nic->phy_dev->send_sdu_func(nic->phy_dev->priv_dev,
470 					  data_buf, data_len,
471 					  nic->pdn_table.dft_eps_id, 0,
472 					  tx_complete, nic, idx,
473 					  nic_type);
474 
475 	if (ret == TX_NO_BUFFER || ret == TX_NO_SPC) {
476 		netif_stop_queue(dev);
477 		if (ret == TX_NO_BUFFER)
478 			ret = 0;
479 		else
480 			ret = -ENOSPC;
481 	} else if (ret == TX_NO_DEV) {
482 		ret = -ENODEV;
483 	}
484 
485 	/* Updates tx stats */
486 	if (ret) {
487 		nic->stats.tx_dropped++;
488 	} else {
489 		nic->stats.tx_packets++;
490 		nic->stats.tx_bytes += data_len;
491 	}
492 	dev_kfree_skb(skb);
493 
494 	return 0;
495 }
496 
497 static struct net_device_stats *gdm_lte_stats(struct net_device *dev)
498 {
499 	struct nic *nic = netdev_priv(dev);
500 
501 	return &nic->stats;
502 }
503 
504 static int gdm_lte_event_send(struct net_device *dev, char *buf, int len)
505 {
506 	struct nic *nic = netdev_priv(dev);
507 	struct hci_packet *hci = (struct hci_packet *)buf;
508 	int idx;
509 	int ret;
510 
511 	ret = sscanf(dev->name, "lte%d", &idx);
512 	if (ret != 1)
513 		return -EINVAL;
514 
515 	return netlink_send(lte_event.sock, idx, 0, buf,
516 			    gdm_dev16_to_cpu(
517 				    nic->phy_dev->get_endian(
518 					    nic->phy_dev->priv_dev), hci->len)
519 			    + HCI_HEADER_SIZE);
520 }
521 
522 static void gdm_lte_event_rcv(struct net_device *dev, u16 type,
523 			      void *msg, int len)
524 {
525 	struct nic *nic = netdev_priv(dev);
526 
527 	nic->phy_dev->send_hci_func(nic->phy_dev->priv_dev, msg, len, NULL,
528 				    NULL);
529 }
530 
531 int gdm_lte_event_init(void)
532 {
533 	if (lte_event.ref_cnt == 0)
534 		lte_event.sock = netlink_init(NETLINK_LTE, gdm_lte_event_rcv);
535 
536 	if (lte_event.sock) {
537 		lte_event.ref_cnt++;
538 		return 0;
539 	}
540 
541 	pr_err("event init failed\n");
542 	return -1;
543 }
544 
545 void gdm_lte_event_exit(void)
546 {
547 	if (lte_event.sock && --lte_event.ref_cnt == 0) {
548 		sock_release(lte_event.sock->sk_socket);
549 		lte_event.sock = NULL;
550 	}
551 }
552 
553 static int find_dev_index(u32 nic_type)
554 {
555 	u8 index;
556 
557 	index = (u8)(nic_type & 0x0000000f);
558 	if (index >= MAX_NIC_TYPE)
559 		return -EINVAL;
560 
561 	return index;
562 }
563 
564 static void gdm_lte_netif_rx(struct net_device *dev, char *buf,
565 			     int len, int flagged_nic_type)
566 {
567 	u32 nic_type;
568 	struct nic *nic;
569 	struct sk_buff *skb;
570 	struct ethhdr eth;
571 	struct vlan_ethhdr vlan_eth;
572 	void *mac_header_data;
573 	u32 mac_header_len;
574 	char ip_version = 0;
575 
576 	nic_type = flagged_nic_type & NIC_TYPE_MASK;
577 	nic = netdev_priv(dev);
578 
579 	if (flagged_nic_type & NIC_TYPE_F_DHCP) {
580 		/* Change the destination mac address
581 		 * with the one requested the IP
582 		 */
583 		if (flagged_nic_type & NIC_TYPE_F_IPV4) {
584 			struct dhcp_packet {
585 				u8 op;      /* BOOTREQUEST or BOOTREPLY */
586 				u8 htype;   /* hardware address type.
587 					     * 1 = 10mb ethernet
588 					     */
589 				u8 hlen;    /* hardware address length */
590 				u8 hops;    /* used by relay agents only */
591 				u32 xid;    /* unique id */
592 				u16 secs;   /* elapsed since client began
593 					     * acquisition/renewal
594 					     */
595 				u16 flags;  /* only one flag so far: */
596 				#define BROADCAST_FLAG 0x8000
597 				/* "I need broadcast replies" */
598 				u32 ciaddr; /* client IP (if client is in
599 					     * BOUND, RENEW or REBINDING state)
600 					     */
601 				u32 yiaddr; /* 'your' (client) IP address */
602 				/* IP address of next server to use in
603 				 * bootstrap, returned in DHCPOFFER,
604 				 * DHCPACK by server
605 				 */
606 				u32 siaddr_nip;
607 				u32 gateway_nip; /* relay agent IP address */
608 				u8 chaddr[16];   /* link-layer client hardware
609 						  * address (MAC)
610 						  */
611 				u8 sname[64];    /* server host name (ASCIZ) */
612 				u8 file[128];    /* boot file name (ASCIZ) */
613 				u32 cookie;      /* fixed first four option
614 						  * bytes (99,130,83,99 dec)
615 						  */
616 			} __packed;
617 			void *addr = buf + sizeof(struct iphdr) +
618 				sizeof(struct udphdr) +
619 				offsetof(struct dhcp_packet, chaddr);
620 			ether_addr_copy(nic->dest_mac_addr, addr);
621 		}
622 	}
623 
624 	if (nic->vlan_id > 0) {
625 		mac_header_data = (void *)&vlan_eth;
626 		mac_header_len = VLAN_ETH_HLEN;
627 	} else {
628 		mac_header_data = (void *)&eth;
629 		mac_header_len = ETH_HLEN;
630 	}
631 
632 	/* Format the data so that it can be put to skb */
633 	ether_addr_copy(mac_header_data, nic->dest_mac_addr);
634 	memcpy(mac_header_data + ETH_ALEN, nic->src_mac_addr, ETH_ALEN);
635 
636 	vlan_eth.h_vlan_TCI = htons(nic->vlan_id);
637 	vlan_eth.h_vlan_proto = htons(ETH_P_8021Q);
638 
639 	if (nic_type == NIC_TYPE_ARP) {
640 		/* Should be response: Only happens because
641 		 * there was a request from the host
642 		 */
643 		eth.h_proto = htons(ETH_P_ARP);
644 		vlan_eth.h_vlan_encapsulated_proto = htons(ETH_P_ARP);
645 	} else {
646 		ip_version = buf[0] >> 4;
647 		if (ip_version == IP_VERSION_4) {
648 			eth.h_proto = htons(ETH_P_IP);
649 			vlan_eth.h_vlan_encapsulated_proto = htons(ETH_P_IP);
650 		} else if (ip_version == IP_VERSION_6) {
651 			eth.h_proto = htons(ETH_P_IPV6);
652 			vlan_eth.h_vlan_encapsulated_proto = htons(ETH_P_IPV6);
653 		} else {
654 			netdev_err(dev, "Unknown IP version %d\n", ip_version);
655 			return;
656 		}
657 	}
658 
659 	/* Alloc skb and reserve align */
660 	skb = dev_alloc_skb(len + mac_header_len + NET_IP_ALIGN);
661 	if (!skb)
662 		return;
663 	skb_reserve(skb, NET_IP_ALIGN);
664 
665 	skb_put_data(skb, mac_header_data, mac_header_len);
666 	skb_put_data(skb, buf, len);
667 
668 	skb->protocol = ((struct ethhdr *)mac_header_data)->h_proto;
669 	skb->dev = dev;
670 	skb_reset_mac_header(skb);
671 	skb_pull(skb, ETH_HLEN);
672 
673 	gdm_lte_rx(skb, nic, nic_type);
674 }
675 
676 static void gdm_lte_multi_sdu_pkt(struct phy_dev *phy_dev, char *buf, int len)
677 {
678 	struct net_device *dev;
679 	struct multi_sdu *multi_sdu = (struct multi_sdu *)buf;
680 	struct sdu *sdu = NULL;
681 	struct gdm_endian *endian = phy_dev->get_endian(phy_dev->priv_dev);
682 	u8 *data = (u8 *)multi_sdu->data;
683 	u16 i = 0;
684 	u16 num_packet;
685 	u16 hci_len;
686 	u16 cmd_evt;
687 	u32 nic_type;
688 	int index;
689 
690 	hci_len = gdm_dev16_to_cpu(endian, multi_sdu->len);
691 	num_packet = gdm_dev16_to_cpu(endian, multi_sdu->num_packet);
692 
693 	for (i = 0; i < num_packet; i++) {
694 		sdu = (struct sdu *)data;
695 
696 		cmd_evt  = gdm_dev16_to_cpu(endian, sdu->cmd_evt);
697 		hci_len  = gdm_dev16_to_cpu(endian, sdu->len);
698 		nic_type = gdm_dev32_to_cpu(endian, sdu->nic_type);
699 
700 		if (cmd_evt != LTE_RX_SDU) {
701 			pr_err("rx sdu wrong hci %04x\n", cmd_evt);
702 			return;
703 		}
704 		if (hci_len < 12) {
705 			pr_err("rx sdu invalid len %d\n", hci_len);
706 			return;
707 		}
708 
709 		index = find_dev_index(nic_type);
710 		if (index < 0) {
711 			pr_err("rx sdu invalid nic_type :%x\n", nic_type);
712 			return;
713 		}
714 		dev = phy_dev->dev[index];
715 		gdm_lte_netif_rx(dev, (char *)sdu->data,
716 				 (int)(hci_len - 12), nic_type);
717 
718 		data += ((hci_len + 3) & 0xfffc) + HCI_HEADER_SIZE;
719 	}
720 }
721 
722 static void gdm_lte_pdn_table(struct net_device *dev, char *buf, int len)
723 {
724 	struct nic *nic = netdev_priv(dev);
725 	struct hci_pdn_table_ind *pdn_table = (struct hci_pdn_table_ind *)buf;
726 
727 	if (pdn_table->activate) {
728 		nic->pdn_table.activate = pdn_table->activate;
729 		nic->pdn_table.dft_eps_id = gdm_dev32_to_cpu(
730 						nic->phy_dev->get_endian(
731 							nic->phy_dev->priv_dev),
732 						pdn_table->dft_eps_id);
733 		nic->pdn_table.nic_type = gdm_dev32_to_cpu(
734 						nic->phy_dev->get_endian(
735 							nic->phy_dev->priv_dev),
736 						pdn_table->nic_type);
737 
738 		netdev_info(dev, "pdn activated, nic_type=0x%x\n",
739 			    nic->pdn_table.nic_type);
740 	} else {
741 		memset(&nic->pdn_table, 0x00, sizeof(struct pdn_table));
742 		netdev_info(dev, "pdn deactivated\n");
743 	}
744 }
745 
746 static int gdm_lte_receive_pkt(struct phy_dev *phy_dev, char *buf, int len)
747 {
748 	struct hci_packet *hci = (struct hci_packet *)buf;
749 	struct hci_pdn_table_ind *pdn_table = (struct hci_pdn_table_ind *)buf;
750 	struct gdm_endian *endian = phy_dev->get_endian(phy_dev->priv_dev);
751 	struct sdu *sdu;
752 	struct net_device *dev;
753 	int ret = 0;
754 	u16 cmd_evt;
755 	u32 nic_type;
756 	int index;
757 
758 	if (!len)
759 		return ret;
760 
761 	cmd_evt = gdm_dev16_to_cpu(endian, hci->cmd_evt);
762 
763 	dev = phy_dev->dev[0];
764 	if (!dev)
765 		return 0;
766 
767 	switch (cmd_evt) {
768 	case LTE_RX_SDU:
769 		sdu = (struct sdu *)hci->data;
770 		nic_type = gdm_dev32_to_cpu(endian, sdu->nic_type);
771 		index = find_dev_index(nic_type);
772 		if (index < 0)
773 			return index;
774 		dev = phy_dev->dev[index];
775 		gdm_lte_netif_rx(dev, hci->data, len, nic_type);
776 		break;
777 	case LTE_RX_MULTI_SDU:
778 		gdm_lte_multi_sdu_pkt(phy_dev, buf, len);
779 		break;
780 	case LTE_LINK_ON_OFF_INDICATION:
781 		netdev_info(dev, "link %s\n",
782 			    ((struct hci_connect_ind *)buf)->connect
783 			    ? "on" : "off");
784 		break;
785 	case LTE_PDN_TABLE_IND:
786 		pdn_table = (struct hci_pdn_table_ind *)buf;
787 		nic_type = gdm_dev32_to_cpu(endian, pdn_table->nic_type);
788 		index = find_dev_index(nic_type);
789 		if (index < 0)
790 			return index;
791 		dev = phy_dev->dev[index];
792 		gdm_lte_pdn_table(dev, buf, len);
793 		/* Fall through */
794 	default:
795 		ret = gdm_lte_event_send(dev, buf, len);
796 		break;
797 	}
798 
799 	return ret;
800 }
801 
802 static int rx_complete(void *arg, void *data, int len, int context)
803 {
804 	struct phy_dev *phy_dev = arg;
805 
806 	return gdm_lte_receive_pkt(phy_dev, data, len);
807 }
808 
809 void start_rx_proc(struct phy_dev *phy_dev)
810 {
811 	int i;
812 
813 	for (i = 0; i < MAX_RX_SUBMIT_COUNT; i++)
814 		phy_dev->rcv_func(phy_dev->priv_dev,
815 				rx_complete, phy_dev, USB_COMPLETE);
816 }
817 
818 static const struct net_device_ops gdm_netdev_ops = {
819 	.ndo_open			= gdm_lte_open,
820 	.ndo_stop			= gdm_lte_close,
821 	.ndo_set_config			= gdm_lte_set_config,
822 	.ndo_start_xmit			= gdm_lte_tx,
823 	.ndo_get_stats			= gdm_lte_stats,
824 };
825 
826 static u8 gdm_lte_macaddr[ETH_ALEN] = {0x00, 0x0a, 0x3b, 0x00, 0x00, 0x00};
827 
828 static void form_mac_address(u8 *dev_addr, u8 *nic_src, u8 *nic_dest,
829 			     u8 *mac_address, u8 index)
830 {
831 	/* Form the dev_addr */
832 	if (!mac_address)
833 		ether_addr_copy(dev_addr, gdm_lte_macaddr);
834 	else
835 		ether_addr_copy(dev_addr, mac_address);
836 
837 	/* The last byte of the mac address
838 	 * should be less than or equal to 0xFC
839 	 */
840 	dev_addr[ETH_ALEN - 1] += index;
841 
842 	/* Create random nic src and copy the first
843 	 * 3 bytes to be the same as dev_addr
844 	 */
845 	eth_random_addr(nic_src);
846 	memcpy(nic_src, dev_addr, 3);
847 
848 	/* Copy the nic_dest from dev_addr*/
849 	ether_addr_copy(nic_dest, dev_addr);
850 }
851 
852 static void validate_mac_address(u8 *mac_address)
853 {
854 	/* if zero address or multicast bit set, restore the default value */
855 	if (is_zero_ether_addr(mac_address) || (mac_address[0] & 0x01)) {
856 		pr_err("MAC invalid, restoring default\n");
857 		memcpy(mac_address, gdm_lte_macaddr, 6);
858 	}
859 }
860 
861 int register_lte_device(struct phy_dev *phy_dev,
862 			struct device *dev, u8 *mac_address)
863 {
864 	struct nic *nic;
865 	struct net_device *net;
866 	char pdn_dev_name[16];
867 	int ret = 0;
868 	u8 index;
869 
870 	validate_mac_address(mac_address);
871 
872 	for (index = 0; index < MAX_NIC_TYPE; index++) {
873 		/* Create device name lteXpdnX */
874 		sprintf(pdn_dev_name, "lte%%dpdn%d", index);
875 
876 		/* Allocate netdev */
877 		net = alloc_netdev(sizeof(struct nic), pdn_dev_name,
878 				   NET_NAME_UNKNOWN, ether_setup);
879 		if (!net) {
880 			pr_err("alloc_netdev failed\n");
881 			ret = -ENOMEM;
882 			goto err;
883 		}
884 		net->netdev_ops = &gdm_netdev_ops;
885 		net->flags &= ~IFF_MULTICAST;
886 		net->mtu = DEFAULT_MTU_SIZE;
887 
888 		nic = netdev_priv(net);
889 		memset(nic, 0, sizeof(struct nic));
890 		nic->netdev = net;
891 		nic->phy_dev = phy_dev;
892 		nic->nic_id = index;
893 
894 		form_mac_address(
895 				net->dev_addr,
896 				nic->src_mac_addr,
897 				nic->dest_mac_addr,
898 				mac_address,
899 				index);
900 
901 		SET_NETDEV_DEV(net, dev);
902 		SET_NETDEV_DEVTYPE(net, &wwan_type);
903 
904 		ret = register_netdev(net);
905 		if (ret)
906 			goto err;
907 
908 		netif_carrier_on(net);
909 
910 		phy_dev->dev[index] = net;
911 	}
912 
913 	return 0;
914 
915 err:
916 	unregister_lte_device(phy_dev);
917 
918 	return ret;
919 }
920 
921 void unregister_lte_device(struct phy_dev *phy_dev)
922 {
923 	struct net_device *net;
924 	int index;
925 
926 	for (index = 0; index < MAX_NIC_TYPE; index++) {
927 		net = phy_dev->dev[index];
928 		if (!net)
929 			continue;
930 
931 		unregister_netdev(net);
932 		free_netdev(net);
933 	}
934 }
935