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linux
1/*
2 * cdc2.c -- CDC Composite driver, with ECM and ACM support
3 *
4 * Copyright (C) 2008 David Brownell
5 * Copyright (C) 2008 Nokia Corporation
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13#include <linux/kernel.h>
14#include <linux/module.h>
15
16#include "u_ether.h"
17#include "u_serial.h"
18
19
20#define DRIVER_DESC "CDC Composite Gadget"
21#define DRIVER_VERSION "King Kamehameha Day 2008"
22
23/*-------------------------------------------------------------------------*/
24
25/* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
26 * Instead: allocate your own, using normal USB-IF procedures.
27 */
28
29/* Thanks to NetChip Technologies for donating this product ID.
30 * It's for devices with only this composite CDC configuration.
31 */
32#define CDC_VENDOR_NUM 0x0525 /* NetChip */
33#define CDC_PRODUCT_NUM 0xa4aa /* CDC Composite: ECM + ACM */
34
35/*-------------------------------------------------------------------------*/
36USB_GADGET_COMPOSITE_OPTIONS();
37
38/*
39 * Kbuild is not very cooperative with respect to linking separately
40 * compiled library objects into one module. So for now we won't use
41 * separate compilation ... ensuring init/exit sections work to shrink
42 * the runtime footprint, and giving us at least some parts of what
43 * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
44 */
45#include "f_ecm.c"
46#include "u_ether.c"
47
48/*-------------------------------------------------------------------------*/
49
50static struct usb_device_descriptor device_desc = {
51 .bLength = sizeof device_desc,
52 .bDescriptorType = USB_DT_DEVICE,
53
54 .bcdUSB = cpu_to_le16(0x0200),
55
56 .bDeviceClass = USB_CLASS_COMM,
57 .bDeviceSubClass = 0,
58 .bDeviceProtocol = 0,
59 /* .bMaxPacketSize0 = f(hardware) */
60
61 /* Vendor and product id can be overridden by module parameters. */
62 .idVendor = cpu_to_le16(CDC_VENDOR_NUM),
63 .idProduct = cpu_to_le16(CDC_PRODUCT_NUM),
64 /* .bcdDevice = f(hardware) */
65 /* .iManufacturer = DYNAMIC */
66 /* .iProduct = DYNAMIC */
67 /* NO SERIAL NUMBER */
68 .bNumConfigurations = 1,
69};
70
71static struct usb_otg_descriptor otg_descriptor = {
72 .bLength = sizeof otg_descriptor,
73 .bDescriptorType = USB_DT_OTG,
74
75 /* REVISIT SRP-only hardware is possible, although
76 * it would not be called "OTG" ...
77 */
78 .bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
79};
80
81static const struct usb_descriptor_header *otg_desc[] = {
82 (struct usb_descriptor_header *) &otg_descriptor,
83 NULL,
84};
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 u8 hostaddr[ETH_ALEN];
106
107/*-------------------------------------------------------------------------*/
108static struct usb_function *f_acm;
109static struct usb_function_instance *fi_serial;
110
111static unsigned char tty_line;
112/*
113 * We _always_ have both CDC ECM and CDC ACM functions.
114 */
115static int __init cdc_do_config(struct usb_configuration *c)
116{
117 struct f_serial_opts *opts;
118 int status;
119
120 if (gadget_is_otg(c->cdev->gadget)) {
121 c->descriptors = otg_desc;
122 c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
123 }
124
125 status = ecm_bind_config(c, hostaddr);
126 if (status < 0)
127 return status;
128
129 fi_serial = usb_get_function_instance("acm");
130 if (IS_ERR(fi_serial))
131 return PTR_ERR(fi_serial);
132
133 opts = container_of(fi_serial, struct f_serial_opts, func_inst);
134 opts->port_num = tty_line;
135
136 f_acm = usb_get_function(fi_serial);
137 if (IS_ERR(f_acm))
138 goto err_func_acm;
139
140 status = usb_add_function(c, f_acm);
141 if (status)
142 goto err_conf;
143 return 0;
144err_conf:
145 usb_put_function(f_acm);
146err_func_acm:
147 usb_put_function_instance(fi_serial);
148 return status;
149}
150
151static struct usb_configuration cdc_config_driver = {
152 .label = "CDC Composite (ECM + ACM)",
153 .bConfigurationValue = 1,
154 /* .iConfiguration = DYNAMIC */
155 .bmAttributes = USB_CONFIG_ATT_SELFPOWER,
156};
157
158/*-------------------------------------------------------------------------*/
159
160static int __init cdc_bind(struct usb_composite_dev *cdev)
161{
162 struct usb_gadget *gadget = cdev->gadget;
163 int status;
164
165 if (!can_support_ecm(cdev->gadget)) {
166 dev_err(&gadget->dev, "controller '%s' not usable\n",
167 gadget->name);
168 return -EINVAL;
169 }
170
171 /* set up network link layer */
172 status = gether_setup(cdev->gadget, hostaddr);
173 if (status < 0)
174 return status;
175
176 /* set up serial link layer */
177 status = gserial_alloc_line(&tty_line);
178 if (status < 0)
179 goto fail0;
180
181 /* Allocate string descriptor numbers ... note that string
182 * contents can be overridden by the composite_dev glue.
183 */
184
185 status = usb_string_ids_tab(cdev, strings_dev);
186 if (status < 0)
187 goto fail1;
188 device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
189 device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
190
191 /* register our configuration */
192 status = usb_add_config(cdev, &cdc_config_driver, cdc_do_config);
193 if (status < 0)
194 goto fail1;
195
196 usb_composite_overwrite_options(cdev, &coverwrite);
197 dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
198 DRIVER_DESC);
199
200 return 0;
201
202fail1:
203 gserial_free_line(tty_line);
204fail0:
205 gether_cleanup();
206 return status;
207}
208
209static int __exit cdc_unbind(struct usb_composite_dev *cdev)
210{
211 usb_put_function(f_acm);
212 usb_put_function_instance(fi_serial);
213 gserial_free_line(tty_line);
214 gether_cleanup();
215 return 0;
216}
217
218static __refdata struct usb_composite_driver cdc_driver = {
219 .name = "g_cdc",
220 .dev = &device_desc,
221 .strings = dev_strings,
222 .max_speed = USB_SPEED_HIGH,
223 .bind = cdc_bind,
224 .unbind = __exit_p(cdc_unbind),
225};
226
227MODULE_DESCRIPTION(DRIVER_DESC);
228MODULE_AUTHOR("David Brownell");
229MODULE_LICENSE("GPL");
230
231static int __init init(void)
232{
233 return usb_composite_probe(&cdc_driver);
234}
235module_init(init);
236
237static void __exit cleanup(void)
238{
239 usb_composite_unregister(&cdc_driver);
240}
241module_exit(cleanup);