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
28 #define DRIVER_DESC "NCM Gadget"
29
30 /*-------------------------------------------------------------------------*/
31
32 /*
33 * Kbuild is not very cooperative with respect to linking separately
34 * compiled library objects into one module. So for now we won't use
35 * separate compilation ... ensuring init/exit sections work to shrink
36 * the runtime footprint, and giving us at least some parts of what
37 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
38 */
39 #include "f_ncm.c"
40 #include "u_ether.c"
41
42 /*-------------------------------------------------------------------------*/
43
44 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
45 * Instead: allocate your own, using normal USB-IF procedures.
46 */
47
48 /* Thanks to NetChip Technologies for donating this product ID.
49 * It's for devices with only CDC Ethernet configurations.
50 */
51 #define CDC_VENDOR_NUM 0x0525 /* NetChip */
52 #define CDC_PRODUCT_NUM 0xa4a1 /* Linux-USB Ethernet Gadget */
53
54 /*-------------------------------------------------------------------------*/
55 USB_GADGET_COMPOSITE_OPTIONS();
56
57 static struct usb_device_descriptor device_desc = {
58 .bLength = sizeof device_desc,
59 .bDescriptorType = USB_DT_DEVICE,
60
61 .bcdUSB = cpu_to_le16 (0x0200),
62
63 .bDeviceClass = USB_CLASS_COMM,
64 .bDeviceSubClass = 0,
65 .bDeviceProtocol = 0,
66 /* .bMaxPacketSize0 = f(hardware) */
67
68 /* Vendor and product id defaults change according to what configs
69 * we support. (As does bNumConfigurations.) These values can
70 * also be overridden by module parameters.
71 */
72 .idVendor = cpu_to_le16 (CDC_VENDOR_NUM),
73 .idProduct = cpu_to_le16 (CDC_PRODUCT_NUM),
74 /* .bcdDevice = f(hardware) */
75 /* .iManufacturer = DYNAMIC */
76 /* .iProduct = DYNAMIC */
77 /* NO SERIAL NUMBER */
78 .bNumConfigurations = 1,
79 };
80
81 static struct usb_otg_descriptor otg_descriptor = {
82 .bLength = sizeof otg_descriptor,
83 .bDescriptorType = USB_DT_OTG,
84
85 /* REVISIT SRP-only hardware is possible, although
86 * it would not be called "OTG" ...
87 */
88 .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
89 };
90
91 static const struct usb_descriptor_header *otg_desc[] = {
92 (struct usb_descriptor_header *) &otg_descriptor,
93 NULL,
94 };
95
96 /* string IDs are assigned dynamically */
97 static struct usb_string strings_dev[] = {
98 [USB_GADGET_MANUFACTURER_IDX].s = "",
99 [USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
100 [USB_GADGET_SERIAL_IDX].s = "",
101 { } /* end of list */
102 };
103
104 static struct usb_gadget_strings stringtab_dev = {
105 .language = 0x0409, /* en-us */
106 .strings = strings_dev,
107 };
108
109 static struct usb_gadget_strings *dev_strings[] = {
110 &stringtab_dev,
111 NULL,
112 };
113
114 struct eth_dev *the_dev;
115 static u8 hostaddr[ETH_ALEN];
116
117 /*-------------------------------------------------------------------------*/
118
ncm_do_config(struct usb_configuration * c)119 static int __init ncm_do_config(struct usb_configuration *c)
120 {
121 /* FIXME alloc iConfiguration string, set it in c->strings */
122
123 if (gadget_is_otg(c->cdev->gadget)) {
124 c->descriptors = otg_desc;
125 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
126 }
127
128 return ncm_bind_config(c, hostaddr, the_dev);
129 }
130
131 static struct usb_configuration ncm_config_driver = {
132 /* .label = f(hardware) */
133 .label = "CDC Ethernet (NCM)",
134 .bConfigurationValue = 1,
135 /* .iConfiguration = DYNAMIC */
136 .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
137 };
138
139 /*-------------------------------------------------------------------------*/
140
gncm_bind(struct usb_composite_dev * cdev)141 static int __init gncm_bind(struct usb_composite_dev *cdev)
142 {
143 struct usb_gadget *gadget = cdev->gadget;
144 int status;
145
146 /* set up network link layer */
147 the_dev = gether_setup(cdev->gadget, hostaddr);
148 if (IS_ERR(the_dev))
149 return PTR_ERR(the_dev);
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 status = usb_add_config(cdev, &ncm_config_driver,
162 ncm_do_config);
163 if (status < 0)
164 goto fail;
165
166 usb_composite_overwrite_options(cdev, &coverwrite);
167 dev_info(&gadget->dev, "%s\n", DRIVER_DESC);
168
169 return 0;
170
171 fail:
172 gether_cleanup(the_dev);
173 return status;
174 }
175
gncm_unbind(struct usb_composite_dev * cdev)176 static int __exit gncm_unbind(struct usb_composite_dev *cdev)
177 {
178 gether_cleanup(the_dev);
179 return 0;
180 }
181
182 static __refdata struct usb_composite_driver ncm_driver = {
183 .name = "g_ncm",
184 .dev = &device_desc,
185 .strings = dev_strings,
186 .max_speed = USB_SPEED_HIGH,
187 .bind = gncm_bind,
188 .unbind = __exit_p(gncm_unbind),
189 };
190
191 MODULE_DESCRIPTION(DRIVER_DESC);
192 MODULE_AUTHOR("Yauheni Kaliuta");
193 MODULE_LICENSE("GPL");
194
init(void)195 static int __init init(void)
196 {
197 return usb_composite_probe(&ncm_driver);
198 }
199 module_init(init);
200
cleanup(void)201 static void __exit cleanup(void)
202 {
203 usb_composite_unregister(&ncm_driver);
204 }
205 module_exit(cleanup);
206