xref: /openbmc/linux/drivers/usb/gadget/legacy/cdc2.c (revision d7a3d85e)
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 #include "u_ecm.h"
19 
20 
21 #define DRIVER_DESC		"CDC Composite Gadget"
22 #define DRIVER_VERSION		"King Kamehameha Day 2008"
23 
24 /*-------------------------------------------------------------------------*/
25 
26 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
27  * Instead:  allocate your own, using normal USB-IF procedures.
28  */
29 
30 /* Thanks to NetChip Technologies for donating this product ID.
31  * It's for devices with only this composite CDC configuration.
32  */
33 #define CDC_VENDOR_NUM		0x0525	/* NetChip */
34 #define CDC_PRODUCT_NUM		0xa4aa	/* CDC Composite: ECM + ACM */
35 
36 USB_GADGET_COMPOSITE_OPTIONS();
37 
38 USB_ETHERNET_MODULE_PARAMETERS();
39 
40 /*-------------------------------------------------------------------------*/
41 
42 static struct usb_device_descriptor device_desc = {
43 	.bLength =		sizeof device_desc,
44 	.bDescriptorType =	USB_DT_DEVICE,
45 
46 	.bcdUSB =		cpu_to_le16(0x0200),
47 
48 	.bDeviceClass =		USB_CLASS_COMM,
49 	.bDeviceSubClass =	0,
50 	.bDeviceProtocol =	0,
51 	/* .bMaxPacketSize0 = f(hardware) */
52 
53 	/* Vendor and product id can be overridden by module parameters.  */
54 	.idVendor =		cpu_to_le16(CDC_VENDOR_NUM),
55 	.idProduct =		cpu_to_le16(CDC_PRODUCT_NUM),
56 	/* .bcdDevice = f(hardware) */
57 	/* .iManufacturer = DYNAMIC */
58 	/* .iProduct = DYNAMIC */
59 	/* NO SERIAL NUMBER */
60 	.bNumConfigurations =	1,
61 };
62 
63 static struct usb_otg_descriptor otg_descriptor = {
64 	.bLength =		sizeof otg_descriptor,
65 	.bDescriptorType =	USB_DT_OTG,
66 
67 	/* REVISIT SRP-only hardware is possible, although
68 	 * it would not be called "OTG" ...
69 	 */
70 	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
71 };
72 
73 static const struct usb_descriptor_header *otg_desc[] = {
74 	(struct usb_descriptor_header *) &otg_descriptor,
75 	NULL,
76 };
77 
78 
79 /* string IDs are assigned dynamically */
80 static struct usb_string strings_dev[] = {
81 	[USB_GADGET_MANUFACTURER_IDX].s = "",
82 	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
83 	[USB_GADGET_SERIAL_IDX].s = "",
84 	{  } /* end of list */
85 };
86 
87 static struct usb_gadget_strings stringtab_dev = {
88 	.language	= 0x0409,	/* en-us */
89 	.strings	= strings_dev,
90 };
91 
92 static struct usb_gadget_strings *dev_strings[] = {
93 	&stringtab_dev,
94 	NULL,
95 };
96 
97 /*-------------------------------------------------------------------------*/
98 static struct usb_function *f_acm;
99 static struct usb_function_instance *fi_serial;
100 
101 static struct usb_function *f_ecm;
102 static struct usb_function_instance *fi_ecm;
103 
104 /*
105  * We _always_ have both CDC ECM and CDC ACM functions.
106  */
107 static int cdc_do_config(struct usb_configuration *c)
108 {
109 	int	status;
110 
111 	if (gadget_is_otg(c->cdev->gadget)) {
112 		c->descriptors = otg_desc;
113 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
114 	}
115 
116 	f_ecm = usb_get_function(fi_ecm);
117 	if (IS_ERR(f_ecm)) {
118 		status = PTR_ERR(f_ecm);
119 		goto err_get_ecm;
120 	}
121 
122 	status = usb_add_function(c, f_ecm);
123 	if (status)
124 		goto err_add_ecm;
125 
126 	f_acm = usb_get_function(fi_serial);
127 	if (IS_ERR(f_acm)) {
128 		status = PTR_ERR(f_acm);
129 		goto err_get_acm;
130 	}
131 
132 	status = usb_add_function(c, f_acm);
133 	if (status)
134 		goto err_add_acm;
135 	return 0;
136 
137 err_add_acm:
138 	usb_put_function(f_acm);
139 err_get_acm:
140 	usb_remove_function(c, f_ecm);
141 err_add_ecm:
142 	usb_put_function(f_ecm);
143 err_get_ecm:
144 	return status;
145 }
146 
147 static struct usb_configuration cdc_config_driver = {
148 	.label			= "CDC Composite (ECM + ACM)",
149 	.bConfigurationValue	= 1,
150 	/* .iConfiguration = DYNAMIC */
151 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
152 };
153 
154 /*-------------------------------------------------------------------------*/
155 
156 static int cdc_bind(struct usb_composite_dev *cdev)
157 {
158 	struct usb_gadget	*gadget = cdev->gadget;
159 	struct f_ecm_opts	*ecm_opts;
160 	int			status;
161 
162 	if (!can_support_ecm(cdev->gadget)) {
163 		dev_err(&gadget->dev, "controller '%s' not usable\n",
164 				gadget->name);
165 		return -EINVAL;
166 	}
167 
168 	fi_ecm = usb_get_function_instance("ecm");
169 	if (IS_ERR(fi_ecm))
170 		return PTR_ERR(fi_ecm);
171 
172 	ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
173 
174 	gether_set_qmult(ecm_opts->net, qmult);
175 	if (!gether_set_host_addr(ecm_opts->net, host_addr))
176 		pr_info("using host ethernet address: %s", host_addr);
177 	if (!gether_set_dev_addr(ecm_opts->net, dev_addr))
178 		pr_info("using self ethernet address: %s", dev_addr);
179 
180 	fi_serial = usb_get_function_instance("acm");
181 	if (IS_ERR(fi_serial)) {
182 		status = PTR_ERR(fi_serial);
183 		goto fail;
184 	}
185 
186 	/* Allocate string descriptor numbers ... note that string
187 	 * contents can be overridden by the composite_dev glue.
188 	 */
189 
190 	status = usb_string_ids_tab(cdev, strings_dev);
191 	if (status < 0)
192 		goto fail1;
193 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
194 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
195 
196 	/* register our configuration */
197 	status = usb_add_config(cdev, &cdc_config_driver, cdc_do_config);
198 	if (status < 0)
199 		goto fail1;
200 
201 	usb_composite_overwrite_options(cdev, &coverwrite);
202 	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
203 			DRIVER_DESC);
204 
205 	return 0;
206 
207 fail1:
208 	usb_put_function_instance(fi_serial);
209 fail:
210 	usb_put_function_instance(fi_ecm);
211 	return status;
212 }
213 
214 static int cdc_unbind(struct usb_composite_dev *cdev)
215 {
216 	usb_put_function(f_acm);
217 	usb_put_function_instance(fi_serial);
218 	if (!IS_ERR_OR_NULL(f_ecm))
219 		usb_put_function(f_ecm);
220 	if (!IS_ERR_OR_NULL(fi_ecm))
221 		usb_put_function_instance(fi_ecm);
222 	return 0;
223 }
224 
225 static struct usb_composite_driver cdc_driver = {
226 	.name		= "g_cdc",
227 	.dev		= &device_desc,
228 	.strings	= dev_strings,
229 	.max_speed	= USB_SPEED_HIGH,
230 	.bind		= cdc_bind,
231 	.unbind		= cdc_unbind,
232 };
233 
234 module_usb_composite_driver(cdc_driver);
235 
236 MODULE_DESCRIPTION(DRIVER_DESC);
237 MODULE_AUTHOR("David Brownell");
238 MODULE_LICENSE("GPL");
239