[mirror_ubuntu-bionic-kernel.git] / drivers / net / usb / kalmia.c

/*
 * USB network interface driver for Samsung Kalmia based LTE USB modem like the
 * Samsung GT-B3730 and GT-B3710.
 *
 * Copyright (C) 2011 Marius Bjoernstad Kotsbak <marius@kotsbak.com>
 *
 * Sponsored by Quicklink Video Distribution Services Ltd.
 *
 * Based on the cdc_eem module.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */

#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ctype.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/crc32.h>
#include <linux/usb/cdc.h>
#include <linux/usb/usbnet.h>
#include <linux/gfp.h>

/*
 * The Samsung Kalmia based LTE USB modems have a CDC ACM port for modem control
 * handled by the "option" module and an ethernet data port handled by this
 * module.
 *
 * The stick must first be switched into modem mode by usb_modeswitch
 * or similar tool. Then the modem gets sent two initialization packets by
 * this module, which gives the MAC address of the device. User space can then
 * connect the modem using AT commands through the ACM port and then use
 * DHCP on the network interface exposed by this module. Network packets are
 * sent to and from the modem in a proprietary format discovered after watching
 * the behavior of the windows driver for the modem.
 *
 * More information about the use of the modem is available in usb_modeswitch
 * forum and the project page:
 *
 * http://www.draisberghof.de/usb_modeswitch/bb/viewtopic.php?t=465
 * https://github.com/mkotsbak/Samsung-GT-B3730-linux-driver
 */

/* #define	DEBUG */
/* #define	VERBOSE */

#define KALMIA_HEADER_LENGTH 6
#define KALMIA_ALIGN_SIZE 4
#define KALMIA_USB_TIMEOUT 10000

/*-------------------------------------------------------------------------*/

static int
kalmia_send_init_packet(struct usbnet *dev, u8 *init_msg, u8 init_msg_len,
	u8 *buffer, u8 expected_len)
{
	int act_len;
	int status;

	netdev_dbg(dev->net, "Sending init packet");

	status = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, 0x02),
		init_msg, init_msg_len, &act_len, KALMIA_USB_TIMEOUT);
	if (status != 0) {
		netdev_err(dev->net,
			"Error sending init packet. Status %i, length %i\n",
			status, act_len);
		return status;
	}
	else if (act_len != init_msg_len) {
		netdev_err(dev->net,
			"Did not send all of init packet. Bytes sent: %i",
			act_len);
	}
	else {
		netdev_dbg(dev->net, "Successfully sent init packet.");
	}

	status = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, 0x81),
		buffer, expected_len, &act_len, KALMIA_USB_TIMEOUT);

	if (status != 0)
		netdev_err(dev->net,
			"Error receiving init result. Status %i, length %i\n",
			status, act_len);
	else if (act_len != expected_len)
		netdev_err(dev->net, "Unexpected init result length: %i\n",
			act_len);

	return status;
}

static int
kalmia_init_and_get_ethernet_addr(struct usbnet *dev, u8 *ethernet_addr)
{
	static const char init_msg_1[] =
		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00,
		0x00, 0x00 };
	static const char init_msg_2[] =
		{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0xf4,
		0x00, 0x00 };
	static const int buflen = 28;
	char *usb_buf;
	int status;

	usb_buf = kmalloc(buflen, GFP_DMA | GFP_KERNEL);
	if (!usb_buf)
		return -ENOMEM;

	memcpy(usb_buf, init_msg_1, 12);
	status = kalmia_send_init_packet(dev, usb_buf, sizeof(init_msg_1)
		/ sizeof(init_msg_1[0]), usb_buf, 24);
	if (status != 0)
		goto out;

	memcpy(usb_buf, init_msg_2, 12);
	status = kalmia_send_init_packet(dev, usb_buf, sizeof(init_msg_2)
		/ sizeof(init_msg_2[0]), usb_buf, 28);
	if (status != 0)
		goto out;

	memcpy(ethernet_addr, usb_buf + 10, ETH_ALEN);
out:
	kfree(usb_buf);
	return status;
}

static int
kalmia_bind(struct usbnet *dev, struct usb_interface *intf)
{
	int status;
	u8 ethernet_addr[ETH_ALEN];

	/* Don't bind to AT command interface */
	if (intf->cur_altsetting->desc.bInterfaceClass != USB_CLASS_VENDOR_SPEC)
		return -EINVAL;

	dev->in = usb_rcvbulkpipe(dev->udev, 0x81 & USB_ENDPOINT_NUMBER_MASK);
	dev->out = usb_sndbulkpipe(dev->udev, 0x02 & USB_ENDPOINT_NUMBER_MASK);
	dev->status = NULL;

	dev->net->hard_header_len += KALMIA_HEADER_LENGTH;
	dev->hard_mtu = 1400;
	dev->rx_urb_size = dev->hard_mtu * 10; // Found as optimal after testing

	status = kalmia_init_and_get_ethernet_addr(dev, ethernet_addr);

	if (status) {
		usb_set_intfdata(intf, NULL);
		usb_driver_release_interface(driver_of(intf), intf);
		return status;
	}

	memcpy(dev->net->dev_addr, ethernet_addr, ETH_ALEN);

	return status;
}

static struct sk_buff *
kalmia_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
{
	struct sk_buff *skb2 = NULL;
	u16 content_len;
	unsigned char *header_start;
	unsigned char ether_type_1, ether_type_2;
	u8 remainder, padlen = 0;

	if (!skb_cloned(skb)) {
		int headroom = skb_headroom(skb);
		int tailroom = skb_tailroom(skb);

		if ((tailroom >= KALMIA_ALIGN_SIZE) && (headroom
			>= KALMIA_HEADER_LENGTH))
			goto done;

		if ((headroom + tailroom) > (KALMIA_HEADER_LENGTH
			+ KALMIA_ALIGN_SIZE)) {
			skb->data = memmove(skb->head + KALMIA_HEADER_LENGTH,
				skb->data, skb->len);
			skb_set_tail_pointer(skb, skb->len);
			goto done;
		}
	}

	skb2 = skb_copy_expand(skb, KALMIA_HEADER_LENGTH,
		KALMIA_ALIGN_SIZE, flags);
	if (!skb2)
		return NULL;

	dev_kfree_skb_any(skb);
	skb = skb2;

done:
	header_start = skb_push(skb, KALMIA_HEADER_LENGTH);
	ether_type_1 = header_start[KALMIA_HEADER_LENGTH + 12];
	ether_type_2 = header_start[KALMIA_HEADER_LENGTH + 13];

	netdev_dbg(dev->net, "Sending etherType: %02x%02x", ether_type_1,
		ether_type_2);

	/* According to empiric data for data packages */
	header_start[0] = 0x57;
	header_start[1] = 0x44;
	content_len = skb->len - KALMIA_HEADER_LENGTH;

	put_unaligned_le16(content_len, &header_start[2]);
	header_start[4] = ether_type_1;
	header_start[5] = ether_type_2;

	/* Align to 4 bytes by padding with zeros */
	remainder = skb->len % KALMIA_ALIGN_SIZE;
	if (remainder > 0) {
		padlen = KALMIA_ALIGN_SIZE - remainder;
		skb_put_zero(skb, padlen);
	}

	netdev_dbg(dev->net,
		"Sending package with length %i and padding %i. Header: %6phC.",
		content_len, padlen, header_start);

	return skb;
}

static int
kalmia_rx_fixup(struct usbnet *dev, struct sk_buff *skb)
{
	/*
	 * Our task here is to strip off framing, leaving skb with one
	 * data frame for the usbnet framework code to process.
	 */
	static const u8 HEADER_END_OF_USB_PACKET[] =
		{ 0x57, 0x5a, 0x00, 0x00, 0x08, 0x00 };
	static const u8 EXPECTED_UNKNOWN_HEADER_1[] =
		{ 0x57, 0x43, 0x1e, 0x00, 0x15, 0x02 };
	static const u8 EXPECTED_UNKNOWN_HEADER_2[] =
		{ 0x57, 0x50, 0x0e, 0x00, 0x00, 0x00 };
	int i = 0;

	/* incomplete header? */
	if (skb->len < KALMIA_HEADER_LENGTH)
		return 0;

	do {
		struct sk_buff *skb2 = NULL;
		u8 *header_start;
		u16 usb_packet_length, ether_packet_length;
		int is_last;

		header_start = skb->data;

		if (unlikely(header_start[0] != 0x57 || header_start[1] != 0x44)) {
			if (!memcmp(header_start, EXPECTED_UNKNOWN_HEADER_1,
				sizeof(EXPECTED_UNKNOWN_HEADER_1)) || !memcmp(
				header_start, EXPECTED_UNKNOWN_HEADER_2,
				sizeof(EXPECTED_UNKNOWN_HEADER_2))) {
				netdev_dbg(dev->net,
					"Received expected unknown frame header: %6phC. Package length: %i\n",
					header_start,
					skb->len - KALMIA_HEADER_LENGTH);
			}
			else {
				netdev_err(dev->net,
					"Received unknown frame header: %6phC. Package length: %i\n",
					header_start,
					skb->len - KALMIA_HEADER_LENGTH);
				return 0;
			}
		}
		else
			netdev_dbg(dev->net,
				"Received header: %6phC. Package length: %i\n",
				header_start, skb->len - KALMIA_HEADER_LENGTH);

		/* subtract start header and end header */
		usb_packet_length = skb->len - (2 * KALMIA_HEADER_LENGTH);
		ether_packet_length = get_unaligned_le16(&header_start[2]);
		skb_pull(skb, KALMIA_HEADER_LENGTH);

		/* Some small packets misses end marker */
		if (usb_packet_length < ether_packet_length) {
			ether_packet_length = usb_packet_length
				+ KALMIA_HEADER_LENGTH;
			is_last = true;
		}
		else {
			netdev_dbg(dev->net, "Correct package length #%i", i
				+ 1);

			is_last = (memcmp(skb->data + ether_packet_length,
				HEADER_END_OF_USB_PACKET,
				sizeof(HEADER_END_OF_USB_PACKET)) == 0);
			if (!is_last) {
				header_start = skb->data + ether_packet_length;
				netdev_dbg(dev->net,
					"End header: %6phC. Package length: %i\n",
					header_start,
					skb->len - KALMIA_HEADER_LENGTH);
			}
		}

		if (is_last) {
			skb2 = skb;
		}
		else {
			skb2 = skb_clone(skb, GFP_ATOMIC);
			if (unlikely(!skb2))
				return 0;
		}

		skb_trim(skb2, ether_packet_length);

		if (is_last) {
			return 1;
		}
		else {
			usbnet_skb_return(dev, skb2);
			skb_pull(skb, ether_packet_length);
		}

		i++;
	}
	while (skb->len);

	return 1;
}

static const struct driver_info kalmia_info = {
	.description = "Samsung Kalmia LTE USB dongle",
	.flags = FLAG_WWAN,
	.bind = kalmia_bind,
	.rx_fixup = kalmia_rx_fixup,
	.tx_fixup = kalmia_tx_fixup
};

/*-------------------------------------------------------------------------*/

static const struct usb_device_id products[] = {
	/* The unswitched USB ID, to get the module auto loaded: */
	{ USB_DEVICE(0x04e8, 0x689a) },
	/* The stick switched into modem (by e.g. usb_modeswitch): */
	{ USB_DEVICE(0x04e8, 0x6889),
		.driver_info = (unsigned long) &kalmia_info, },
	{ /* EMPTY == end of list */} };
MODULE_DEVICE_TABLE( usb, products);

static struct usb_driver kalmia_driver = {
	.name = "kalmia",
	.id_table = products,
	.probe = usbnet_probe,
	.disconnect = usbnet_disconnect,
	.suspend = usbnet_suspend,
	.resume = usbnet_resume,
	.disable_hub_initiated_lpm = 1,
};

module_usb_driver(kalmia_driver);

MODULE_AUTHOR("Marius Bjoernstad Kotsbak <marius@kotsbak.com>");
MODULE_DESCRIPTION("Samsung Kalmia USB network driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
d4026123 MK	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>
d4026123 MK	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
	59	static int
	60	kalmia_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
99	static int
100	kalmia_init_and_get_ethernet_addr(struct usbnet dev, u8 ethernet_addr)
101	{
bd0d7aa6	102	static const char init_msg_1[] =
d4026123 MK	103	{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x00,
d4026123 MK	104	0x00, 0x00 };
bd0d7aa6	105	static const char init_msg_2[] =
d4026123 MK	106	{ 0x57, 0x50, 0x04, 0x00, 0x00, 0x00, 0x00, 0x02, 0x00, 0xf4,
d4026123 MK	107	0x00, 0x00 };
bd0d7aa6	108	static const int buflen = 28;
7cdfa4a3	109	char *usb_buf;
d4026123 MK	110	int status;
d4026123 MK	111
7cdfa4a3 MK	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);
d4026123	119	if (status != 0)
ec7646fe	120	goto out;
d4026123	121
7cdfa4a3 MK	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);
d4026123	125	if (status != 0)
ec7646fe	126	goto out;
d4026123	127
7cdfa4a3	128	memcpy(ethernet_addr, usb_buf + 10, ETH_ALEN);
ec7646fe	129	out:
7cdfa4a3	130	kfree(usb_buf);
d4026123 MK	131	return status;
	132	}
	133
	134	static int
	135	kalmia_bind(struct usbnet dev, struct usb_interface intf)
	136	{
5c18e80b	137	int status;
d4026123 MK	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
e30520c2	154	if (status) {
d4026123 MK	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);
d4026123 MK	161
	162	return status;
	163	}
	164
	165	static struct sk_buff *
	166	kalmia_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
7cdfa4a3 MK	199	done:
7cdfa4a3 MK	200	header_start = skb_push(skb, KALMIA_HEADER_LENGTH);
d4026123 MK	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;
d4026123	211
7cdfa4a3	212	put_unaligned_le16(content_len, &header_start[2]);
d4026123 MK	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;
b080db58	220	skb_put_zero(skb, padlen);
d4026123 MK	221	}
d4026123 MK	222
cbb963de AS	223	netdev_dbg(dev->net,
	224	"Sending package with length %i and padding %i. Header: %6phC.",
	225	content_len, padlen, header_start);
d4026123 MK	226
	227	return skb;
	228	}
	229
	230	static int
	231	kalmia_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	*/
bd0d7aa6	237	static const u8 HEADER_END_OF_USB_PACKET[] =
d4026123	238	{ 0x57, 0x5a, 0x00, 0x00, 0x08, 0x00 };
bd0d7aa6	239	static const u8 EXPECTED_UNKNOWN_HEADER_1[] =
d4026123	240	{ 0x57, 0x43, 0x1e, 0x00, 0x15, 0x02 };
bd0d7aa6	241	static const u8 EXPECTED_UNKNOWN_HEADER_2[] =
d4026123	242	{ 0x57, 0x50, 0x0e, 0x00, 0x00, 0x00 };
7cdfa4a3	243	int i = 0;
d4026123 MK	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))) {
cbb963de AS	262	netdev_dbg(dev->net,
	263	"Received expected unknown frame header: %6phC. Package length: %i\n",
	264	header_start,
d4026123 MK	265	skb->len - KALMIA_HEADER_LENGTH);
	266	}
	267	else {
cbb963de AS	268	netdev_err(dev->net,
	269	"Received unknown frame header: %6phC. Package length: %i\n",
	270	header_start,
d4026123 MK	271	skb->len - KALMIA_HEADER_LENGTH);
	272	return 0;
	273	}
	274	}
	275	else
cbb963de AS	276	netdev_dbg(dev->net,
	277	"Received header: %6phC. Package length: %i\n",
	278	header_start, skb->len - KALMIA_HEADER_LENGTH);
d4026123 MK	279
	280	/* subtract start header and end header */
	281	usb_packet_length = skb->len - (2 * KALMIA_HEADER_LENGTH);
7cdfa4a3	282	ether_packet_length = get_unaligned_le16(&header_start[2]);
d4026123 MK	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;
cbb963de AS	300	netdev_dbg(dev->net,
	301	"End header: %6phC. Package length: %i\n",
	302	header_start,
d4026123 MK	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
	333	static 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
	343	static const struct usb_device_id products[] = {
	344	/* The unswitched USB ID, to get the module auto loaded: */
	345	{ USB_DEVICE(0x04e8, 0x689a) },
08a7e621	346	/* The stick switched into modem (by e.g. usb_modeswitch): */
d4026123 MK	347	{ USB_DEVICE(0x04e8, 0x6889),
	348	.driver_info = (unsigned long) &kalmia_info, },
	349	{ /* EMPTY == end of list */} };
	350	MODULE_DEVICE_TABLE( usb, products);
	351
	352	static struct usb_driver kalmia_driver = {
	353	.name = "kalmia",
	354	.id_table = products,
	355	.probe = usbnet_probe,
	356	.disconnect = usbnet_disconnect,
	357	.suspend = usbnet_suspend,
e1f12eb6 SS	358	.resume = usbnet_resume,
e1f12eb6 SS	359	.disable_hub_initiated_lpm = 1,
d4026123 MK	360	};
d4026123 MK	361
d632eb1b	362	module_usb_driver(kalmia_driver);
d4026123 MK	363
	364	MODULE_AUTHOR("Marius Bjoernstad Kotsbak <marius@kotsbak.com>");
	365	MODULE_DESCRIPTION("Samsung Kalmia USB network driver");
	366	MODULE_LICENSE("GPL");