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 struct usb_otg_descriptor otg_descriptor = {
 73	.bLength =		sizeof otg_descriptor,
 74	.bDescriptorType =	USB_DT_OTG,
 75
 76	/* REVISIT SRP-only hardware is possible, although
 77	 * it would not be called "OTG" ...
 78	 */
 79	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
 80};
 81
 82static const struct usb_descriptor_header *otg_desc[] = {
 83	(struct usb_descriptor_header *) &otg_descriptor,
 84	NULL,
 85};
 86
 87/* string IDs are assigned dynamically */
 88static struct usb_string strings_dev[] = {
 89	[USB_GADGET_MANUFACTURER_IDX].s = "",
 90	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
 91	[USB_GADGET_SERIAL_IDX].s = "",
 92	{  } /* end of list */
 93};
 94
 95static struct usb_gadget_strings stringtab_dev = {
 96	.language	= 0x0409,	/* en-us */
 97	.strings	= strings_dev,
 98};
 99
100static struct usb_gadget_strings *dev_strings[] = {
101	&stringtab_dev,
102	NULL,
103};
104
105static struct usb_function_instance *f_ncm_inst;
106static struct usb_function *f_ncm;
107
108/*-------------------------------------------------------------------------*/
109
110static int __init ncm_do_config(struct usb_configuration *c)
111{
112	int status;
113
114	/* FIXME alloc iConfiguration string, set it in c->strings */
115
116	if (gadget_is_otg(c->cdev->gadget)) {
117		c->descriptors = otg_desc;
118		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
119	}
120
121	f_ncm = usb_get_function(f_ncm_inst);
122	if (IS_ERR(f_ncm)) {
123		status = PTR_ERR(f_ncm);
124		return status;
125	}
126
127	status = usb_add_function(c, f_ncm);
128	if (status < 0) {
129		usb_put_function(f_ncm);
130		return status;
131	}
132
133	return 0;
134}
135
136static struct usb_configuration ncm_config_driver = {
137	/* .label = f(hardware) */
138	.label			= "CDC Ethernet (NCM)",
139	.bConfigurationValue	= 1,
140	/* .iConfiguration = DYNAMIC */
141	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
142};
143
144/*-------------------------------------------------------------------------*/
145
146static int __init gncm_bind(struct usb_composite_dev *cdev)
147{
148	struct usb_gadget	*gadget = cdev->gadget;
149	struct f_ncm_opts	*ncm_opts;
150	int			status;
151
152	f_ncm_inst = usb_get_function_instance("ncm");
153	if (IS_ERR(f_ncm_inst))
154		return PTR_ERR(f_ncm_inst);
155
156	ncm_opts = container_of(f_ncm_inst, struct f_ncm_opts, func_inst);
157
158	gether_set_qmult(ncm_opts->net, qmult);
159	if (!gether_set_host_addr(ncm_opts->net, host_addr))
160		pr_info("using host ethernet address: %s", host_addr);
161	if (!gether_set_dev_addr(ncm_opts->net, dev_addr))
162		pr_info("using self ethernet address: %s", dev_addr);
163
164	/* Allocate string descriptor numbers ... note that string
165	 * contents can be overridden by the composite_dev glue.
166	 */
167
168	status = usb_string_ids_tab(cdev, strings_dev);
169	if (status < 0)
170		goto fail;
171	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
172	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
173
174	status = usb_add_config(cdev, &ncm_config_driver,
175				ncm_do_config);
176	if (status < 0)
177		goto fail;
178
179	usb_composite_overwrite_options(cdev, &coverwrite);
180	dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
181
182	return 0;
183
184fail:
185	usb_put_function_instance(f_ncm_inst);
186	return status;
187}
188
189static int __exit gncm_unbind(struct usb_composite_dev *cdev)
190{
191	if (!IS_ERR_OR_NULL(f_ncm))
192		usb_put_function(f_ncm);
193	if (!IS_ERR_OR_NULL(f_ncm_inst))
194		usb_put_function_instance(f_ncm_inst);
195	return 0;
196}
197
198static __refdata struct usb_composite_driver ncm_driver = {
199	.name		= "g_ncm",
200	.dev		= &device_desc,
201	.strings	= dev_strings,
202	.max_speed	= USB_SPEED_HIGH,
203	.bind		= gncm_bind,
204	.unbind		= __exit_p(gncm_unbind),
205};
206
207MODULE_DESCRIPTION(DRIVER_DESC);
208MODULE_AUTHOR("Yauheni Kaliuta");
209MODULE_LICENSE("GPL");
210
211static int __init init(void)
212{
213	return usb_composite_probe(&ncm_driver);
214}
215module_init(init);
216
217static void __exit cleanup(void)
218{
219	usb_composite_unregister(&ncm_driver);
220}
221module_exit(cleanup);