1/*
2 * ncm.c -- NCM gadget driver
3 *
4 * Copyright (C) 2010 Nokia Corporation
5 * Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
6 *
7 * The driver borrows from ether.c which is:
8 *
9 * Copyright (C) 2003-2005,2008 David Brownell
10 * Copyright (C) 2003-2004 Robert Schwebel, Benedikt Spranger
11 * Copyright (C) 2008 Nokia Corporation
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 */
18
19/* #define DEBUG */
20/* #define VERBOSE_DEBUG */
21
22#include <linux/kernel.h>
23#include <linux/module.h>
24#include <linux/usb/composite.h>
25
26#include "u_ether.h"
27#include "u_ncm.h"
28
29#define DRIVER_DESC		"NCM Gadget"
30
31/*-------------------------------------------------------------------------*/
32
33/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
34 * Instead:  allocate your own, using normal USB-IF procedures.
35 */
36
37/* Thanks to NetChip Technologies for donating this product ID.
38 * It's for devices with only CDC Ethernet configurations.
39 */
40#define CDC_VENDOR_NUM		0x0525	/* NetChip */
41#define CDC_PRODUCT_NUM		0xa4a1	/* Linux-USB Ethernet Gadget */
42
43/*-------------------------------------------------------------------------*/
44USB_GADGET_COMPOSITE_OPTIONS();
45
46USB_ETHERNET_MODULE_PARAMETERS();
47
48static struct usb_device_descriptor device_desc = {
49	.bLength =		sizeof device_desc,
50	.bDescriptorType =	USB_DT_DEVICE,
51
52	.bcdUSB =		cpu_to_le16 (0x0200),
53
54	.bDeviceClass =		USB_CLASS_COMM,
55	.bDeviceSubClass =	0,
56	.bDeviceProtocol =	0,
57	/* .bMaxPacketSize0 = f(hardware) */
58
59	/* Vendor and product id defaults change according to what configs
60	 * we support.  (As does bNumConfigurations.)  These values can
61	 * also be overridden by module parameters.
62	 */
63	.idVendor =		cpu_to_le16 (CDC_VENDOR_NUM),
64	.idProduct =		cpu_to_le16 (CDC_PRODUCT_NUM),
65	/* .bcdDevice = f(hardware) */
66	/* .iManufacturer = DYNAMIC */
67	/* .iProduct = DYNAMIC */
68	/* NO SERIAL NUMBER */
69	.bNumConfigurations =	1,
70};
71
72static const struct usb_descriptor_header *otg_desc[2];
73
74/* string IDs are assigned dynamically */
75static struct usb_string strings_dev[] = {
76	[USB_GADGET_MANUFACTURER_IDX].s = "",
77	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
78	[USB_GADGET_SERIAL_IDX].s = "",
79	{  } /* end of list */
80};
81
82static struct usb_gadget_strings stringtab_dev = {
83	.language	= 0x0409,	/* en-us */
84	.strings	= strings_dev,
85};
86
87static struct usb_gadget_strings *dev_strings[] = {
88	&stringtab_dev,
89	NULL,
90};
91
92static struct usb_function_instance *f_ncm_inst;
93static struct usb_function *f_ncm;
94
95/*-------------------------------------------------------------------------*/
96
97static int ncm_do_config(struct usb_configuration *c)
98{
99	int status;
100
101	/* FIXME alloc iConfiguration string, set it in c->strings */
102
103	if (gadget_is_otg(c->cdev->gadget)) {
104		c->descriptors = otg_desc;
105		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
106	}
107
108	f_ncm = usb_get_function(f_ncm_inst);
109	if (IS_ERR(f_ncm)) {
110		status = PTR_ERR(f_ncm);
111		return status;
112	}
113
114	status = usb_add_function(c, f_ncm);
115	if (status < 0) {
116		usb_put_function(f_ncm);
117		return status;
118	}
119
120	return 0;
121}
122
123static struct usb_configuration ncm_config_driver = {
124	/* .label = f(hardware) */
125	.label			= "CDC Ethernet (NCM)",
126	.bConfigurationValue	= 1,
127	/* .iConfiguration = DYNAMIC */
128	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
129};
130
131/*-------------------------------------------------------------------------*/
132
133static int gncm_bind(struct usb_composite_dev *cdev)
134{
135	struct usb_gadget	*gadget = cdev->gadget;
136	struct f_ncm_opts	*ncm_opts;
137	int			status;
138
139	f_ncm_inst = usb_get_function_instance("ncm");
140	if (IS_ERR(f_ncm_inst))
141		return PTR_ERR(f_ncm_inst);
142
143	ncm_opts = container_of(f_ncm_inst, struct f_ncm_opts, func_inst);
144
145	gether_set_qmult(ncm_opts->net, qmult);
146	if (!gether_set_host_addr(ncm_opts->net, host_addr))
147		pr_info("using host ethernet address: %s", host_addr);
148	if (!gether_set_dev_addr(ncm_opts->net, dev_addr))
149		pr_info("using self ethernet address: %s", dev_addr);
150
151	/* Allocate string descriptor numbers ... note that string
152	 * contents can be overridden by the composite_dev glue.
153	 */
154
155	status = usb_string_ids_tab(cdev, strings_dev);
156	if (status < 0)
157		goto fail;
158	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
159	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
160
161	if (gadget_is_otg(gadget) && !otg_desc[0]) {
162		struct usb_descriptor_header *usb_desc;
163
164		usb_desc = usb_otg_descriptor_alloc(gadget);
165		if (!usb_desc)
166			goto fail;
167		usb_otg_descriptor_init(gadget, usb_desc);
168		otg_desc[0] = usb_desc;
169		otg_desc[1] = NULL;
170	}
171
172	status = usb_add_config(cdev, &ncm_config_driver,
173				ncm_do_config);
174	if (status < 0)
175		goto fail1;
176
177	usb_composite_overwrite_options(cdev, &coverwrite);
178	dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
179
180	return 0;
181
182fail1:
183	kfree(otg_desc[0]);
184	otg_desc[0] = NULL;
185fail:
186	usb_put_function_instance(f_ncm_inst);
187	return status;
188}
189
190static int gncm_unbind(struct usb_composite_dev *cdev)
191{
192	if (!IS_ERR_OR_NULL(f_ncm))
193		usb_put_function(f_ncm);
194	if (!IS_ERR_OR_NULL(f_ncm_inst))
195		usb_put_function_instance(f_ncm_inst);
196	kfree(otg_desc[0]);
197	otg_desc[0] = NULL;
198
199	return 0;
200}
201
202static struct usb_composite_driver ncm_driver = {
203	.name		= "g_ncm",
204	.dev		= &device_desc,
205	.strings	= dev_strings,
206	.max_speed	= USB_SPEED_HIGH,
207	.bind		= gncm_bind,
208	.unbind		= gncm_unbind,
209};
210
211module_usb_composite_driver(ncm_driver);
212
213MODULE_DESCRIPTION(DRIVER_DESC);
214MODULE_AUTHOR("Yauheni Kaliuta");
215MODULE_LICENSE("GPL");
216