aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/usb/huawei_cdc_ncm.c
blob: 735f7dadb9a0740dea86ed58d55df1ae58edf9ef (plain) (blame)
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
209
210
211
212
213
214
215
216
217
218
219
220
221
/* huawei_cdc_ncm.c - handles Huawei devices using the CDC NCM protocol as
 * transport layer.
 * Copyright (C) 2013	 Enrico Mioso <mrkiko.rs@gmail.com>
 *
 *
 * ABSTRACT:
 * This driver handles devices resembling the CDC NCM standard, but
 * encapsulating another protocol inside it. An example are some Huawei 3G
 * devices, exposing an embedded AT channel where you can set up the NCM
 * connection.
 * This code has been heavily inspired by the cdc_mbim.c driver, which is
 * Copyright (c) 2012  Smith Micro Software, Inc.
 * Copyright (c) 2012  Bjørn Mork <bjorn@mork.no>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/ethtool.h>
#include <linux/if_vlan.h>
#include <linux/ip.h>
#include <linux/mii.h>
#include <linux/usb.h>
#include <linux/usb/cdc.h>
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc-wdm.h>
#include <linux/usb/cdc_ncm.h>

/* Driver data */
struct huawei_cdc_ncm_state {
	struct cdc_ncm_ctx *ctx;
	atomic_t pmcount;
	struct usb_driver *subdriver;
	struct usb_interface *control;
	struct usb_interface *data;
};

static int huawei_cdc_ncm_manage_power(struct usbnet *usbnet_dev, int on)
{
	struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
	int rv;

	if ((on && atomic_add_return(1, &drvstate->pmcount) == 1) ||
			(!on && atomic_dec_and_test(&drvstate->pmcount))) {
		rv = usb_autopm_get_interface(usbnet_dev->intf);
		usbnet_dev->intf->needs_remote_wakeup = on;
		if (!rv)
			usb_autopm_put_interface(usbnet_dev->intf);
	}
	return 0;
}

static int huawei_cdc_ncm_wdm_manage_power(struct usb_interface *intf,
					   int status)
{
	struct usbnet *usbnet_dev = usb_get_intfdata(intf);

	/* can be called while disconnecting */
	if (!usbnet_dev)
		return 0;

	return huawei_cdc_ncm_manage_power(usbnet_dev, status);
}


static int huawei_cdc_ncm_bind(struct usbnet *usbnet_dev,
			       struct usb_interface *intf)
{
	struct cdc_ncm_ctx *ctx;
	struct usb_driver *subdriver = ERR_PTR(-ENODEV);
	int ret = -ENODEV;
	struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;

	/* altsetting should always be 1 for NCM devices - so we hard-coded
	 * it here
	 */
	ret = cdc_ncm_bind_common(usbnet_dev, intf, 1);
	if (ret)
		goto err;

	ctx = drvstate->ctx;

	if (usbnet_dev->status)
		/* The wMaxCommand buffer must be big enough to hold
		 * any message from the modem. Experience has shown
		 * that some replies are more than 256 bytes long
		 */
		subdriver = usb_cdc_wdm_register(ctx->control,
						 &usbnet_dev->status->desc,
						 1024, /* wMaxCommand */
						 huawei_cdc_ncm_wdm_manage_power);
	if (IS_ERR(subdriver)) {
		ret = PTR_ERR(subdriver);
		cdc_ncm_unbind(usbnet_dev, intf);
		goto err;
	}

	/* Prevent usbnet from using the status descriptor */
	usbnet_dev->status = NULL;

	drvstate->subdriver = subdriver;

err:
	return ret;
}

static void huawei_cdc_ncm_unbind(struct usbnet *usbnet_dev,
				  struct usb_interface *intf)
{
	struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
	struct cdc_ncm_ctx *ctx = drvstate->ctx;

	if (drvstate->subdriver && drvstate->subdriver->disconnect)
		drvstate->subdriver->disconnect(ctx->control);
	drvstate->subdriver = NULL;

	cdc_ncm_unbind(usbnet_dev, intf);
}

static int huawei_cdc_ncm_suspend(struct usb_interface *intf,
				  pm_message_t message)
{
	int ret = 0;
	struct usbnet *usbnet_dev = usb_get_intfdata(intf);
	struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
	struct cdc_ncm_ctx *ctx = drvstate->ctx;

	if (ctx == NULL) {
		ret = -ENODEV;
		goto error;
	}

	ret = usbnet_suspend(intf, message);
	if (ret < 0)
		goto error;

	if (intf == ctx->control &&
		drvstate->subdriver &&
		drvstate->subdriver->suspend)
		ret = drvstate->subdriver->suspend(intf, message);
	if (ret < 0)
		usbnet_resume(intf);

error:
	return ret;
}

static int huawei_cdc_ncm_resume(struct usb_interface *intf)
{
	int ret = 0;
	struct usbnet *usbnet_dev = usb_get_intfdata(intf);
	struct huawei_cdc_ncm_state *drvstate = (void *)&usbnet_dev->data;
	bool callsub;
	struct cdc_ncm_ctx *ctx = drvstate->ctx;

	/* should we call subdriver's resume function? */
	callsub =
		(intf == ctx->control &&
		drvstate->subdriver &&
		drvstate->subdriver->resume);

	if (callsub)
		ret = drvstate->subdriver->resume(intf);
	if (ret < 0)
		goto err;
	ret = usbnet_resume(intf);
	if (ret < 0 && callsub)
		drvstate->subdriver->suspend(intf, PMSG_SUSPEND);
err:
	return ret;
}

static const struct driver_info huawei_cdc_ncm_info = {
	.description = "Huawei CDC NCM device",
	.flags = FLAG_NO_SETINT | FLAG_MULTI_PACKET | FLAG_WWAN,
	.bind = huawei_cdc_ncm_bind,
	.unbind = huawei_cdc_ncm_unbind,
	.manage_power = huawei_cdc_ncm_manage_power,
	.rx_fixup = cdc_ncm_rx_fixup,
	.tx_fixup = cdc_ncm_tx_fixup,
};

static const struct usb_device_id huawei_cdc_ncm_devs[] = {
	/* Huawei NCM devices disguised as vendor specific */
	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x16),
	  .driver_info = (unsigned long)&huawei_cdc_ncm_info,
	},
	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x46),
	  .driver_info = (unsigned long)&huawei_cdc_ncm_info,
	},
	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x02, 0x76),
	  .driver_info = (unsigned long)&huawei_cdc_ncm_info,
	},
	{ USB_VENDOR_AND_INTERFACE_INFO(0x12d1, 0xff, 0x03, 0x16),
	  .driver_info = (unsigned long)&huawei_cdc_ncm_info,
	},

	/* Terminating entry */
	{
	},
};
MODULE_DEVICE_TABLE(usb, huawei_cdc_ncm_devs);

static struct usb_driver huawei_cdc_ncm_driver = {
	.name = "huawei_cdc_ncm",
	.id_table = huawei_cdc_ncm_devs,
	.probe = usbnet_probe,
	.disconnect = usbnet_disconnect,
	.suspend = huawei_cdc_ncm_suspend,
	.resume = huawei_cdc_ncm_resume,
	.reset_resume = huawei_cdc_ncm_resume,
	.supports_autosuspend = 1,
	.disable_hub_initiated_lpm = 1,
};
module_usb_driver(huawei_cdc_ncm_driver);
MODULE_AUTHOR("Enrico Mioso <mrkiko.rs@gmail.com>");
MODULE_DESCRIPTION("USB CDC NCM host driver with encapsulated protocol support");
MODULE_LICENSE("GPL");