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v3.15
  1/*
  2 * USB network interface driver for Samsung Kalmia based LTE USB modem like the
  3 * Samsung GT-B3730 and GT-B3710.
  4 *
  5 * Copyright (C) 2011 Marius Bjoernstad Kotsbak <marius@kotsbak.com>
  6 *
  7 * Sponsored by Quicklink Video Distribution Services Ltd.
  8 *
  9 * Based on the cdc_eem module.
 10 *
 11 * This program is free software; you can redistribute it and/or modify
 12 * it under the terms of the GNU General Public License as published by
 13 * the Free Software Foundation; either version 2 of the License, or
 14 * (at your option) any later version.
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/netdevice.h>
 19#include <linux/etherdevice.h>
 20#include <linux/ctype.h>
 21#include <linux/ethtool.h>
 22#include <linux/workqueue.h>
 23#include <linux/mii.h>
 24#include <linux/usb.h>
 25#include <linux/crc32.h>
 26#include <linux/usb/cdc.h>
 27#include <linux/usb/usbnet.h>
 28#include <linux/gfp.h>
 29
 30/*
 31 * The Samsung Kalmia based LTE USB modems have a CDC ACM port for modem control
 32 * handled by the "option" module and an ethernet data port handled by this
 33 * module.
 34 *
 35 * The stick must first be switched into modem mode by usb_modeswitch
 36 * or similar tool. Then the modem gets sent two initialization packets by
 37 * this module, which gives the MAC address of the device. User space can then
 38 * connect the modem using AT commands through the ACM port and then use
 39 * DHCP on the network interface exposed by this module. Network packets are
 40 * sent to and from the modem in a proprietary format discovered after watching
 41 * the behavior of the windows driver for the modem.
 42 *
 43 * More information about the use of the modem is available in usb_modeswitch
 44 * forum and the project page:
 45 *
 46 * http://www.draisberghof.de/usb_modeswitch/bb/viewtopic.php?t=465
 47 * https://github.com/mkotsbak/Samsung-GT-B3730-linux-driver
 48 */
 49
 50/* #define	DEBUG */
 51/* #define	VERBOSE */
 52
 53#define KALMIA_HEADER_LENGTH 6
 54#define KALMIA_ALIGN_SIZE 4
 55#define KALMIA_USB_TIMEOUT 10000
 56
 57/*-------------------------------------------------------------------------*/
 58
 59static int
 60kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
 61	u8 *buffer, u8 expected_len)
 62{
 63	int act_len;
 64	int status;
 65
 66	netdev_dbg(dev->net, "Sending init packet");
 67
 68	status = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 0x02),
 69		init_msg, init_msg_len, &act_len, KALMIA_USB_TIMEOUT);
 70	if (status != 0) {
 71		netdev_err(dev->net,
 72			"Error sending init packet. Status %i, length %i\n",
 73			status, act_len);
 74		return status;
 75	}
 76	else if (act_len != init_msg_len) {
 77		netdev_err(dev->net,
 78			"Did not send all of init packet. Bytes sent: %i",
 79			act_len);
 80	}
 81	else {
 82		netdev_dbg(dev->net, "Successfully sent init packet.");
 83	}
 84
 85	status = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, 0x81),
 86		buffer, expected_len, &act_len, KALMIA_USB_TIMEOUT);
 87
 88	if (status != 0)
 89		netdev_err(dev->net,
 90			"Error receiving init result. Status %i, length %i\n",
 91			status, act_len);
 92	else if (act_len != expected_len)
 93		netdev_err(dev->net, "Unexpected init result length: %i\n",
 94			act_len);
 95
 96	return status;
 97}
 98
 99static int
100kalmia_init_and_get_ethernet_addr(struct usbnet *dev, u8 *ethernet_addr)
101{
102	static const char init_msg_1[] =
103		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00,
104		0x00, 0x00 };
105	static const char init_msg_2[] =
106		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0xf4,
107		0x00, 0x00 };
108	static const int buflen = 28;
109	char *usb_buf;
110	int status;
111
112	usb_buf = kmalloc(buflen, GFP_DMA | GFP_KERNEL);
113	if (!usb_buf)
114		return -ENOMEM;
115
116	memcpy(usb_buf, init_msg_1, 12);
117	status = kalmia_send_init_packet(dev, usb_buf, sizeof(init_msg_1)
118		/ sizeof(init_msg_1[0]), usb_buf, 24);
119	if (status != 0)
120		return status;
121
122	memcpy(usb_buf, init_msg_2, 12);
123	status = kalmia_send_init_packet(dev, usb_buf, sizeof(init_msg_2)
124		/ sizeof(init_msg_2[0]), usb_buf, 28);
125	if (status != 0)
126		return status;
127
128	memcpy(ethernet_addr, usb_buf + 10, ETH_ALEN);
129
130	kfree(usb_buf);
131	return status;
132}
133
134static int
135kalmia_bind(struct usbnet *dev, struct usb_interface *intf)
136{
137	int status;
138	u8 ethernet_addr[ETH_ALEN];
139
140	/* Don't bind to AT command interface */
141	if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
142		return -EINVAL;
143
144	dev->in = usb_rcvbulkpipe(dev->udev, 0x81 & USB_ENDPOINT_NUMBER_MASK);
145	dev->out = usb_sndbulkpipe(dev->udev, 0x02 & USB_ENDPOINT_NUMBER_MASK);
146	dev->status = NULL;
147
148	dev->net->hard_header_len += KALMIA_HEADER_LENGTH;
149	dev->hard_mtu = 1400;
150	dev->rx_urb_size = dev->hard_mtu * 10; // Found as optimal after testing
151
152	status = kalmia_init_and_get_ethernet_addr(dev, ethernet_addr);
153
154	if (status < 0) {
155		usb_set_intfdata(intf, NULL);
156		usb_driver_release_interface(driver_of(intf), intf);
157		return status;
158	}
159
160	memcpy(dev->net->dev_addr, ethernet_addr, ETH_ALEN);
161
162	return status;
163}
164
165static struct sk_buff *
166kalmia_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
167{
168	struct sk_buff *skb2 = NULL;
169	u16 content_len;
170	unsigned char *header_start;
171	unsigned char ether_type_1, ether_type_2;
172	u8 remainder, padlen = 0;
173
174	if (!skb_cloned(skb)) {
175		int headroom = skb_headroom(skb);
176		int tailroom = skb_tailroom(skb);
177
178		if ((tailroom >= KALMIA_ALIGN_SIZE) && (headroom
179			>= KALMIA_HEADER_LENGTH))
180			goto done;
181
182		if ((headroom + tailroom) > (KALMIA_HEADER_LENGTH
183			+ KALMIA_ALIGN_SIZE)) {
184			skb->data = memmove(skb->head + KALMIA_HEADER_LENGTH,
185				skb->data, skb->len);
186			skb_set_tail_pointer(skb, skb->len);
187			goto done;
188		}
189	}
190
191	skb2 = skb_copy_expand(skb, KALMIA_HEADER_LENGTH,
192		KALMIA_ALIGN_SIZE, flags);
193	if (!skb2)
194		return NULL;
195
196	dev_kfree_skb_any(skb);
197	skb = skb2;
198
199done:
200	header_start = skb_push(skb, KALMIA_HEADER_LENGTH);
201	ether_type_1 = header_start[KALMIA_HEADER_LENGTH + 12];
202	ether_type_2 = header_start[KALMIA_HEADER_LENGTH + 13];
203
204	netdev_dbg(dev->net, "Sending etherType: %02x%02x", ether_type_1,
205		ether_type_2);
206
207	/* According to empiric data for data packages */
208	header_start[0] = 0x57;
209	header_start[1] = 0x44;
210	content_len = skb->len - KALMIA_HEADER_LENGTH;
211
212	put_unaligned_le16(content_len, &header_start[2]);
213	header_start[4] = ether_type_1;
214	header_start[5] = ether_type_2;
215
216	/* Align to 4 bytes by padding with zeros */
217	remainder = skb->len % KALMIA_ALIGN_SIZE;
218	if (remainder > 0) {
219		padlen = KALMIA_ALIGN_SIZE - remainder;
220		memset(skb_put(skb, padlen), 0, padlen);
221	}
222
223	netdev_dbg(dev->net,
224		"Sending package with length %i and padding %i. Header: %6phC.",
225		content_len, padlen, header_start);
226
227	return skb;
228}
229
230static int
231kalmia_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
232{
233	/*
234	 * Our task here is to strip off framing, leaving skb with one
235	 * data frame for the usbnet framework code to process.
236	 */
237	static const u8 HEADER_END_OF_USB_PACKET[] =
238		{ 0x57, 0x5a, 0x00, 0x00, 0x08, 0x00 };
239	static const u8 EXPECTED_UNKNOWN_HEADER_1[] =
240		{ 0x57, 0x43, 0x1e, 0x00, 0x15, 0x02 };
241	static const u8 EXPECTED_UNKNOWN_HEADER_2[] =
242		{ 0x57, 0x50, 0x0e, 0x00, 0x00, 0x00 };
243	int i = 0;
244
245	/* incomplete header? */
246	if (skb->len < KALMIA_HEADER_LENGTH)
247		return 0;
248
249	do {
250		struct sk_buff *skb2 = NULL;
251		u8 *header_start;
252		u16 usb_packet_length, ether_packet_length;
253		int is_last;
254
255		header_start = skb->data;
256
257		if (unlikely(header_start[0] != 0x57 || header_start[1] != 0x44)) {
258			if (!memcmp(header_start, EXPECTED_UNKNOWN_HEADER_1,
259				sizeof(EXPECTED_UNKNOWN_HEADER_1)) || !memcmp(
260				header_start, EXPECTED_UNKNOWN_HEADER_2,
261				sizeof(EXPECTED_UNKNOWN_HEADER_2))) {
262				netdev_dbg(dev->net,
263					"Received expected unknown frame header: %6phC. Package length: %i\n",
264					header_start,
265					skb->len - KALMIA_HEADER_LENGTH);
266			}
267			else {
268				netdev_err(dev->net,
269					"Received unknown frame header: %6phC. Package length: %i\n",
270					header_start,
271					skb->len - KALMIA_HEADER_LENGTH);
272				return 0;
273			}
274		}
275		else
276			netdev_dbg(dev->net,
277				"Received header: %6phC. Package length: %i\n",
278				header_start, skb->len - KALMIA_HEADER_LENGTH);
279
280		/* subtract start header and end header */
281		usb_packet_length = skb->len - (2 * KALMIA_HEADER_LENGTH);
282		ether_packet_length = get_unaligned_le16(&header_start[2]);
283		skb_pull(skb, KALMIA_HEADER_LENGTH);
284
285		/* Some small packets misses end marker */
286		if (usb_packet_length < ether_packet_length) {
287			ether_packet_length = usb_packet_length
288				+ KALMIA_HEADER_LENGTH;
289			is_last = true;
290		}
291		else {
292			netdev_dbg(dev->net, "Correct package length #%i", i
293				+ 1);
294
295			is_last = (memcmp(skb->data + ether_packet_length,
296				HEADER_END_OF_USB_PACKET,
297				sizeof(HEADER_END_OF_USB_PACKET)) == 0);
298			if (!is_last) {
299				header_start = skb->data + ether_packet_length;
300				netdev_dbg(dev->net,
301					"End header: %6phC. Package length: %i\n",
302					header_start,
303					skb->len - KALMIA_HEADER_LENGTH);
304			}
305		}
306
307		if (is_last) {
308			skb2 = skb;
309		}
310		else {
311			skb2 = skb_clone(skb, GFP_ATOMIC);
312			if (unlikely(!skb2))
313				return 0;
314		}
315
316		skb_trim(skb2, ether_packet_length);
317
318		if (is_last) {
319			return 1;
320		}
321		else {
322			usbnet_skb_return(dev, skb2);
323			skb_pull(skb, ether_packet_length);
324		}
325
326		i++;
327	}
328	while (skb->len);
329
330	return 1;
331}
332
333static const struct driver_info kalmia_info = {
334	.description = "Samsung Kalmia LTE USB dongle",
335	.flags = FLAG_WWAN,
336	.bind = kalmia_bind,
337	.rx_fixup = kalmia_rx_fixup,
338	.tx_fixup = kalmia_tx_fixup
339};
340
341/*-------------------------------------------------------------------------*/
342
343static const struct usb_device_id products[] = {
344	/* The unswitched USB ID, to get the module auto loaded: */
345	{ USB_DEVICE(0x04e8, 0x689a) },
346	/* The stick swithed into modem (by e.g. usb_modeswitch): */
347	{ USB_DEVICE(0x04e8, 0x6889),
348		.driver_info = (unsigned long) &kalmia_info, },
349	{ /* EMPTY == end of list */} };
350MODULE_DEVICE_TABLE( usb, products);
351
352static struct usb_driver kalmia_driver = {
353	.name = "kalmia",
354	.id_table = products,
355	.probe = usbnet_probe,
356	.disconnect = usbnet_disconnect,
357	.suspend = usbnet_suspend,
358	.resume = usbnet_resume,
359	.disable_hub_initiated_lpm = 1,
360};
361
362module_usb_driver(kalmia_driver);
363
364MODULE_AUTHOR("Marius Bjoernstad Kotsbak <marius@kotsbak.com>");
365MODULE_DESCRIPTION("Samsung Kalmia USB network driver");
366MODULE_LICENSE("GPL");
v4.17
  1/*
  2 * USB network interface driver for Samsung Kalmia based LTE USB modem like the
  3 * Samsung GT-B3730 and GT-B3710.
  4 *
  5 * Copyright (C) 2011 Marius Bjoernstad Kotsbak <marius@kotsbak.com>
  6 *
  7 * Sponsored by Quicklink Video Distribution Services Ltd.
  8 *
  9 * Based on the cdc_eem module.
 10 *
 11 * This program is free software; you can redistribute it and/or modify
 12 * it under the terms of the GNU General Public License as published by
 13 * the Free Software Foundation; either version 2 of the License, or
 14 * (at your option) any later version.
 15 */
 16
 17#include <linux/module.h>
 18#include <linux/netdevice.h>
 19#include <linux/etherdevice.h>
 20#include <linux/ctype.h>
 21#include <linux/ethtool.h>
 22#include <linux/workqueue.h>
 23#include <linux/mii.h>
 24#include <linux/usb.h>
 25#include <linux/crc32.h>
 26#include <linux/usb/cdc.h>
 27#include <linux/usb/usbnet.h>
 28#include <linux/gfp.h>
 29
 30/*
 31 * The Samsung Kalmia based LTE USB modems have a CDC ACM port for modem control
 32 * handled by the "option" module and an ethernet data port handled by this
 33 * module.
 34 *
 35 * The stick must first be switched into modem mode by usb_modeswitch
 36 * or similar tool. Then the modem gets sent two initialization packets by
 37 * this module, which gives the MAC address of the device. User space can then
 38 * connect the modem using AT commands through the ACM port and then use
 39 * DHCP on the network interface exposed by this module. Network packets are
 40 * sent to and from the modem in a proprietary format discovered after watching
 41 * the behavior of the windows driver for the modem.
 42 *
 43 * More information about the use of the modem is available in usb_modeswitch
 44 * forum and the project page:
 45 *
 46 * http://www.draisberghof.de/usb_modeswitch/bb/viewtopic.php?t=465
 47 * https://github.com/mkotsbak/Samsung-GT-B3730-linux-driver
 48 */
 49
 50/* #define	DEBUG */
 51/* #define	VERBOSE */
 52
 53#define KALMIA_HEADER_LENGTH 6
 54#define KALMIA_ALIGN_SIZE 4
 55#define KALMIA_USB_TIMEOUT 10000
 56
 57/*-------------------------------------------------------------------------*/
 58
 59static int
 60kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
 61	u8 *buffer, u8 expected_len)
 62{
 63	int act_len;
 64	int status;
 65
 66	netdev_dbg(dev->net, "Sending init packet");
 67
 68	status = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 0x02),
 69		init_msg, init_msg_len, &act_len, KALMIA_USB_TIMEOUT);
 70	if (status != 0) {
 71		netdev_err(dev->net,
 72			"Error sending init packet. Status %i, length %i\n",
 73			status, act_len);
 74		return status;
 75	}
 76	else if (act_len != init_msg_len) {
 77		netdev_err(dev->net,
 78			"Did not send all of init packet. Bytes sent: %i",
 79			act_len);
 80	}
 81	else {
 82		netdev_dbg(dev->net, "Successfully sent init packet.");
 83	}
 84
 85	status = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, 0x81),
 86		buffer, expected_len, &act_len, KALMIA_USB_TIMEOUT);
 87
 88	if (status != 0)
 89		netdev_err(dev->net,
 90			"Error receiving init result. Status %i, length %i\n",
 91			status, act_len);
 92	else if (act_len != expected_len)
 93		netdev_err(dev->net, "Unexpected init result length: %i\n",
 94			act_len);
 95
 96	return status;
 97}
 98
 99static int
100kalmia_init_and_get_ethernet_addr(struct usbnet *dev, u8 *ethernet_addr)
101{
102	static const char init_msg_1[] =
103		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00,
104		0x00, 0x00 };
105	static const char init_msg_2[] =
106		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0xf4,
107		0x00, 0x00 };
108	static const int buflen = 28;
109	char *usb_buf;
110	int status;
111
112	usb_buf = kmalloc(buflen, GFP_DMA | GFP_KERNEL);
113	if (!usb_buf)
114		return -ENOMEM;
115
116	memcpy(usb_buf, init_msg_1, 12);
117	status = kalmia_send_init_packet(dev, usb_buf, ARRAY_SIZE(init_msg_1),
118					 usb_buf, 24);
119	if (status != 0)
120		return status;
121
122	memcpy(usb_buf, init_msg_2, 12);
123	status = kalmia_send_init_packet(dev, usb_buf, ARRAY_SIZE(init_msg_2),
124					 usb_buf, 28);
125	if (status != 0)
126		return status;
127
128	memcpy(ethernet_addr, usb_buf + 10, ETH_ALEN);
129
130	kfree(usb_buf);
131	return status;
132}
133
134static int
135kalmia_bind(struct usbnet *dev, struct usb_interface *intf)
136{
137	int status;
138	u8 ethernet_addr[ETH_ALEN];
139
140	/* Don't bind to AT command interface */
141	if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
142		return -EINVAL;
143
144	dev->in = usb_rcvbulkpipe(dev->udev, 0x81 & USB_ENDPOINT_NUMBER_MASK);
145	dev->out = usb_sndbulkpipe(dev->udev, 0x02 & USB_ENDPOINT_NUMBER_MASK);
146	dev->status = NULL;
147
148	dev->net->hard_header_len += KALMIA_HEADER_LENGTH;
149	dev->hard_mtu = 1400;
150	dev->rx_urb_size = dev->hard_mtu * 10; // Found as optimal after testing
151
152	status = kalmia_init_and_get_ethernet_addr(dev, ethernet_addr);
153	if (status)
 
 
 
154		return status;
 
155
156	memcpy(dev->net->dev_addr, ethernet_addr, ETH_ALEN);
157
158	return status;
159}
160
161static struct sk_buff *
162kalmia_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
163{
164	struct sk_buff *skb2 = NULL;
165	u16 content_len;
166	unsigned char *header_start;
167	unsigned char ether_type_1, ether_type_2;
168	u8 remainder, padlen = 0;
169
170	if (!skb_cloned(skb)) {
171		int headroom = skb_headroom(skb);
172		int tailroom = skb_tailroom(skb);
173
174		if ((tailroom >= KALMIA_ALIGN_SIZE) && (headroom
175			>= KALMIA_HEADER_LENGTH))
176			goto done;
177
178		if ((headroom + tailroom) > (KALMIA_HEADER_LENGTH
179			+ KALMIA_ALIGN_SIZE)) {
180			skb->data = memmove(skb->head + KALMIA_HEADER_LENGTH,
181				skb->data, skb->len);
182			skb_set_tail_pointer(skb, skb->len);
183			goto done;
184		}
185	}
186
187	skb2 = skb_copy_expand(skb, KALMIA_HEADER_LENGTH,
188		KALMIA_ALIGN_SIZE, flags);
189	if (!skb2)
190		return NULL;
191
192	dev_kfree_skb_any(skb);
193	skb = skb2;
194
195done:
196	header_start = skb_push(skb, KALMIA_HEADER_LENGTH);
197	ether_type_1 = header_start[KALMIA_HEADER_LENGTH + 12];
198	ether_type_2 = header_start[KALMIA_HEADER_LENGTH + 13];
199
200	netdev_dbg(dev->net, "Sending etherType: %02x%02x", ether_type_1,
201		ether_type_2);
202
203	/* According to empiric data for data packages */
204	header_start[0] = 0x57;
205	header_start[1] = 0x44;
206	content_len = skb->len - KALMIA_HEADER_LENGTH;
207
208	put_unaligned_le16(content_len, &header_start[2]);
209	header_start[4] = ether_type_1;
210	header_start[5] = ether_type_2;
211
212	/* Align to 4 bytes by padding with zeros */
213	remainder = skb->len % KALMIA_ALIGN_SIZE;
214	if (remainder > 0) {
215		padlen = KALMIA_ALIGN_SIZE - remainder;
216		skb_put_zero(skb, padlen);
217	}
218
219	netdev_dbg(dev->net,
220		"Sending package with length %i and padding %i. Header: %6phC.",
221		content_len, padlen, header_start);
222
223	return skb;
224}
225
226static int
227kalmia_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
228{
229	/*
230	 * Our task here is to strip off framing, leaving skb with one
231	 * data frame for the usbnet framework code to process.
232	 */
233	static const u8 HEADER_END_OF_USB_PACKET[] =
234		{ 0x57, 0x5a, 0x00, 0x00, 0x08, 0x00 };
235	static const u8 EXPECTED_UNKNOWN_HEADER_1[] =
236		{ 0x57, 0x43, 0x1e, 0x00, 0x15, 0x02 };
237	static const u8 EXPECTED_UNKNOWN_HEADER_2[] =
238		{ 0x57, 0x50, 0x0e, 0x00, 0x00, 0x00 };
239	int i = 0;
240
241	/* incomplete header? */
242	if (skb->len < KALMIA_HEADER_LENGTH)
243		return 0;
244
245	do {
246		struct sk_buff *skb2 = NULL;
247		u8 *header_start;
248		u16 usb_packet_length, ether_packet_length;
249		int is_last;
250
251		header_start = skb->data;
252
253		if (unlikely(header_start[0] != 0x57 || header_start[1] != 0x44)) {
254			if (!memcmp(header_start, EXPECTED_UNKNOWN_HEADER_1,
255				sizeof(EXPECTED_UNKNOWN_HEADER_1)) || !memcmp(
256				header_start, EXPECTED_UNKNOWN_HEADER_2,
257				sizeof(EXPECTED_UNKNOWN_HEADER_2))) {
258				netdev_dbg(dev->net,
259					"Received expected unknown frame header: %6phC. Package length: %i\n",
260					header_start,
261					skb->len - KALMIA_HEADER_LENGTH);
262			}
263			else {
264				netdev_err(dev->net,
265					"Received unknown frame header: %6phC. Package length: %i\n",
266					header_start,
267					skb->len - KALMIA_HEADER_LENGTH);
268				return 0;
269			}
270		}
271		else
272			netdev_dbg(dev->net,
273				"Received header: %6phC. Package length: %i\n",
274				header_start, skb->len - KALMIA_HEADER_LENGTH);
275
276		/* subtract start header and end header */
277		usb_packet_length = skb->len - (2 * KALMIA_HEADER_LENGTH);
278		ether_packet_length = get_unaligned_le16(&header_start[2]);
279		skb_pull(skb, KALMIA_HEADER_LENGTH);
280
281		/* Some small packets misses end marker */
282		if (usb_packet_length < ether_packet_length) {
283			ether_packet_length = usb_packet_length
284				+ KALMIA_HEADER_LENGTH;
285			is_last = true;
286		}
287		else {
288			netdev_dbg(dev->net, "Correct package length #%i", i
289				+ 1);
290
291			is_last = (memcmp(skb->data + ether_packet_length,
292				HEADER_END_OF_USB_PACKET,
293				sizeof(HEADER_END_OF_USB_PACKET)) == 0);
294			if (!is_last) {
295				header_start = skb->data + ether_packet_length;
296				netdev_dbg(dev->net,
297					"End header: %6phC. Package length: %i\n",
298					header_start,
299					skb->len - KALMIA_HEADER_LENGTH);
300			}
301		}
302
303		if (is_last) {
304			skb2 = skb;
305		}
306		else {
307			skb2 = skb_clone(skb, GFP_ATOMIC);
308			if (unlikely(!skb2))
309				return 0;
310		}
311
312		skb_trim(skb2, ether_packet_length);
313
314		if (is_last) {
315			return 1;
316		}
317		else {
318			usbnet_skb_return(dev, skb2);
319			skb_pull(skb, ether_packet_length);
320		}
321
322		i++;
323	}
324	while (skb->len);
325
326	return 1;
327}
328
329static const struct driver_info kalmia_info = {
330	.description = "Samsung Kalmia LTE USB dongle",
331	.flags = FLAG_WWAN,
332	.bind = kalmia_bind,
333	.rx_fixup = kalmia_rx_fixup,
334	.tx_fixup = kalmia_tx_fixup
335};
336
337/*-------------------------------------------------------------------------*/
338
339static const struct usb_device_id products[] = {
340	/* The unswitched USB ID, to get the module auto loaded: */
341	{ USB_DEVICE(0x04e8, 0x689a) },
342	/* The stick switched into modem (by e.g. usb_modeswitch): */
343	{ USB_DEVICE(0x04e8, 0x6889),
344		.driver_info = (unsigned long) &kalmia_info, },
345	{ /* EMPTY == end of list */} };
346MODULE_DEVICE_TABLE( usb, products);
347
348static struct usb_driver kalmia_driver = {
349	.name = "kalmia",
350	.id_table = products,
351	.probe = usbnet_probe,
352	.disconnect = usbnet_disconnect,
353	.suspend = usbnet_suspend,
354	.resume = usbnet_resume,
355	.disable_hub_initiated_lpm = 1,
356};
357
358module_usb_driver(kalmia_driver);
359
360MODULE_AUTHOR("Marius Bjoernstad Kotsbak <marius@kotsbak.com>");
361MODULE_DESCRIPTION("Samsung Kalmia USB network driver");
362MODULE_LICENSE("GPL");