aboutsummaryrefslogtreecommitdiff
path: root/net/caif/caif_usb.c
blob: 5fc9eca8cd4149b2cc102ea32b0ae131db4e8452 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/*
 * CAIF USB handler
 * Copyright (C) ST-Ericsson AB 2011
 * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
 * License terms: GNU General Public License (GPL) version 2
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__

#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/usbnet.h>
#include <net/netns/generic.h>
#include <net/caif/caif_dev.h>
#include <net/caif/caif_layer.h>
#include <net/caif/cfpkt.h>
#include <net/caif/cfcnfg.h>

MODULE_LICENSE("GPL");

#define CFUSB_PAD_DESCR_SZ 1	/* Alignment descriptor length */
#define CFUSB_ALIGNMENT 4	/* Number of bytes to align. */
#define CFUSB_MAX_HEADLEN (CFUSB_PAD_DESCR_SZ + CFUSB_ALIGNMENT-1)
#define STE_USB_VID 0x04cc	/* USB Product ID for ST-Ericsson */
#define STE_USB_PID_CAIF 0x2306	/* Product id for CAIF Modems */

struct cfusbl {
	struct cflayer layer;
	u8 tx_eth_hdr[ETH_HLEN];
};

static bool pack_added;

static int cfusbl_receive(struct cflayer *layr, struct cfpkt *pkt)
{
	u8 hpad;

	/* Remove padding. */
	cfpkt_extr_head(pkt, &hpad, 1);
	cfpkt_extr_head(pkt, NULL, hpad);
	return layr->up->receive(layr->up, pkt);
}

static int cfusbl_transmit(struct cflayer *layr, struct cfpkt *pkt)
{
	struct caif_payload_info *info;
	u8 hpad;
	u8 zeros[CFUSB_ALIGNMENT];
	struct sk_buff *skb;
	struct cfusbl *usbl = container_of(layr, struct cfusbl, layer);

	skb = cfpkt_tonative(pkt);

	skb_reset_network_header(skb);
	skb->protocol = htons(ETH_P_IP);

	info = cfpkt_info(pkt);
	hpad = (info->hdr_len + CFUSB_PAD_DESCR_SZ) & (CFUSB_ALIGNMENT - 1);

	if (skb_headroom(skb) < ETH_HLEN + CFUSB_PAD_DESCR_SZ + hpad) {
		pr_warn("Headroom to small\n");
		kfree_skb(skb);
		return -EIO;
	}
	memset(zeros, 0, hpad);

	cfpkt_add_head(pkt, zeros, hpad);
	cfpkt_add_head(pkt, &hpad, 1);
	cfpkt_add_head(pkt, usbl->tx_eth_hdr, sizeof(usbl->tx_eth_hdr));
	return layr->dn->transmit(layr->dn, pkt);
}

static void cfusbl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
					int phyid)
{
	if (layr->up && layr->up->ctrlcmd)
		layr->up->ctrlcmd(layr->up, ctrl, layr->id);
}

struct cflayer *cfusbl_create(int phyid, u8 ethaddr[ETH_ALEN],
					u8 braddr[ETH_ALEN])
{
	struct cfusbl *this = kmalloc(sizeof(struct cfusbl), GFP_ATOMIC);

	if (!this) {
		pr_warn("Out of memory\n");
		return NULL;
	}
	caif_assert(offsetof(struct cfusbl, layer) == 0);

	memset(this, 0, sizeof(struct cflayer));
	this->layer.receive = cfusbl_receive;
	this->layer.transmit = cfusbl_transmit;
	this->layer.ctrlcmd = cfusbl_ctrlcmd;
	snprintf(this->layer.name, CAIF_LAYER_NAME_SZ, "usb%d", phyid);
	this->layer.id = phyid;

	/*
	 * Construct TX ethernet header:
	 *	0-5	destination address
	 *	5-11	source address
	 *	12-13	protocol type
	 */
	memcpy(&this->tx_eth_hdr[ETH_ALEN], braddr, ETH_ALEN);
	memcpy(&this->tx_eth_hdr[ETH_ALEN], ethaddr, ETH_ALEN);
	this->tx_eth_hdr[12] = cpu_to_be16(ETH_P_802_EX1) & 0xff;
	this->tx_eth_hdr[13] = (cpu_to_be16(ETH_P_802_EX1) >> 8) & 0xff;
	pr_debug("caif ethernet TX-header dst:%pM src:%pM type:%02x%02x\n",
			this->tx_eth_hdr, this->tx_eth_hdr + ETH_ALEN,
			this->tx_eth_hdr[12], this->tx_eth_hdr[13]);

	return (struct cflayer *) this;
}

static struct packet_type caif_usb_type __read_mostly = {
	.type = cpu_to_be16(ETH_P_802_EX1),
};

static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
			      void *arg)
{
	struct net_device *dev = arg;
	struct caif_dev_common common;
	struct cflayer *layer, *link_support;
	struct usbnet	*usbnet = netdev_priv(dev);
	struct usb_device	*usbdev = usbnet->udev;
	struct ethtool_drvinfo drvinfo;

	/*
	 * Quirks: High-jack ethtool to find if we have a NCM device,
	 * and find it's VID/PID.
	 */
	if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL)
		return 0;

	dev->ethtool_ops->get_drvinfo(dev, &drvinfo);
	if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0)
		return 0;

	pr_debug("USB CDC NCM device VID:0x%4x PID:0x%4x\n",
		le16_to_cpu(usbdev->descriptor.idVendor),
		le16_to_cpu(usbdev->descriptor.idProduct));

	/* Check for VID/PID that supports CAIF */
	if (!(le16_to_cpu(usbdev->descriptor.idVendor) == STE_USB_VID &&
		le16_to_cpu(usbdev->descriptor.idProduct) == STE_USB_PID_CAIF))
		return 0;

	if (what == NETDEV_UNREGISTER)
		module_put(THIS_MODULE);

	if (what != NETDEV_REGISTER)
		return 0;

	__module_get(THIS_MODULE);

	memset(&common, 0, sizeof(common));
	common.use_frag = false;
	common.use_fcs = false;
	common.use_stx = false;
	common.link_select = CAIF_LINK_HIGH_BANDW;
	common.flowctrl = NULL;

	link_support = cfusbl_create(dev->ifindex, dev->dev_addr,
					dev->broadcast);

	if (!link_support)
		return -ENOMEM;

	if (dev->num_tx_queues > 1)
		pr_warn("USB device uses more than one tx queue\n");

	caif_enroll_dev(dev, &common, link_support, CFUSB_MAX_HEADLEN,
			&layer, &caif_usb_type.func);
	if (!pack_added)
		dev_add_pack(&caif_usb_type);
	pack_added = true;

	strncpy(layer->name, dev->name,
			sizeof(layer->name) - 1);
	layer->name[sizeof(layer->name) - 1] = 0;

	return 0;
}

static struct notifier_block caif_device_notifier = {
	.notifier_call = cfusbl_device_notify,
	.priority = 0,
};

static int __init cfusbl_init(void)
{
	return register_netdevice_notifier(&caif_device_notifier);
}

static void __exit cfusbl_exit(void)
{
	unregister_netdevice_notifier(&caif_device_notifier);
	dev_remove_pack(&caif_usb_type);
}

module_init(cfusbl_init);
module_exit(cfusbl_exit);