xref: /openbmc/linux/drivers/usb/gadget/legacy/cdc2.c (revision eb3fcf00)
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 const struct usb_descriptor_header *otg_desc[2];
64 
65 /* string IDs are assigned dynamically */
66 static struct usb_string strings_dev[] = {
67 	[USB_GADGET_MANUFACTURER_IDX].s = "",
68 	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
69 	[USB_GADGET_SERIAL_IDX].s = "",
70 	{  } /* end of list */
71 };
72 
73 static struct usb_gadget_strings stringtab_dev = {
74 	.language	= 0x0409,	/* en-us */
75 	.strings	= strings_dev,
76 };
77 
78 static struct usb_gadget_strings *dev_strings[] = {
79 	&stringtab_dev,
80 	NULL,
81 };
82 
83 /*-------------------------------------------------------------------------*/
84 static struct usb_function *f_acm;
85 static struct usb_function_instance *fi_serial;
86 
87 static struct usb_function *f_ecm;
88 static struct usb_function_instance *fi_ecm;
89 
90 /*
91  * We _always_ have both CDC ECM and CDC ACM functions.
92  */
93 static int cdc_do_config(struct usb_configuration *c)
94 {
95 	int	status;
96 
97 	if (gadget_is_otg(c->cdev->gadget)) {
98 		c->descriptors = otg_desc;
99 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
100 	}
101 
102 	f_ecm = usb_get_function(fi_ecm);
103 	if (IS_ERR(f_ecm)) {
104 		status = PTR_ERR(f_ecm);
105 		goto err_get_ecm;
106 	}
107 
108 	status = usb_add_function(c, f_ecm);
109 	if (status)
110 		goto err_add_ecm;
111 
112 	f_acm = usb_get_function(fi_serial);
113 	if (IS_ERR(f_acm)) {
114 		status = PTR_ERR(f_acm);
115 		goto err_get_acm;
116 	}
117 
118 	status = usb_add_function(c, f_acm);
119 	if (status)
120 		goto err_add_acm;
121 	return 0;
122 
123 err_add_acm:
124 	usb_put_function(f_acm);
125 err_get_acm:
126 	usb_remove_function(c, f_ecm);
127 err_add_ecm:
128 	usb_put_function(f_ecm);
129 err_get_ecm:
130 	return status;
131 }
132 
133 static struct usb_configuration cdc_config_driver = {
134 	.label			= "CDC Composite (ECM + ACM)",
135 	.bConfigurationValue	= 1,
136 	/* .iConfiguration = DYNAMIC */
137 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
138 };
139 
140 /*-------------------------------------------------------------------------*/
141 
142 static int cdc_bind(struct usb_composite_dev *cdev)
143 {
144 	struct usb_gadget	*gadget = cdev->gadget;
145 	struct f_ecm_opts	*ecm_opts;
146 	int			status;
147 
148 	if (!can_support_ecm(cdev->gadget)) {
149 		dev_err(&gadget->dev, "controller '%s' not usable\n",
150 				gadget->name);
151 		return -EINVAL;
152 	}
153 
154 	fi_ecm = usb_get_function_instance("ecm");
155 	if (IS_ERR(fi_ecm))
156 		return PTR_ERR(fi_ecm);
157 
158 	ecm_opts = container_of(fi_ecm, struct f_ecm_opts, func_inst);
159 
160 	gether_set_qmult(ecm_opts->net, qmult);
161 	if (!gether_set_host_addr(ecm_opts->net, host_addr))
162 		pr_info("using host ethernet address: %s", host_addr);
163 	if (!gether_set_dev_addr(ecm_opts->net, dev_addr))
164 		pr_info("using self ethernet address: %s", dev_addr);
165 
166 	fi_serial = usb_get_function_instance("acm");
167 	if (IS_ERR(fi_serial)) {
168 		status = PTR_ERR(fi_serial);
169 		goto fail;
170 	}
171 
172 	/* Allocate string descriptor numbers ... note that string
173 	 * contents can be overridden by the composite_dev glue.
174 	 */
175 
176 	status = usb_string_ids_tab(cdev, strings_dev);
177 	if (status < 0)
178 		goto fail1;
179 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
180 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
181 
182 	if (gadget_is_otg(gadget) && !otg_desc[0]) {
183 		struct usb_descriptor_header *usb_desc;
184 
185 		usb_desc = usb_otg_descriptor_alloc(gadget);
186 		if (!usb_desc)
187 			goto fail1;
188 		usb_otg_descriptor_init(gadget, usb_desc);
189 		otg_desc[0] = usb_desc;
190 		otg_desc[1] = NULL;
191 	}
192 
193 	/* register our configuration */
194 	status = usb_add_config(cdev, &cdc_config_driver, cdc_do_config);
195 	if (status < 0)
196 		goto fail2;
197 
198 	usb_composite_overwrite_options(cdev, &coverwrite);
199 	dev_info(&gadget->dev, "%s, version: " DRIVER_VERSION "\n",
200 			DRIVER_DESC);
201 
202 	return 0;
203 
204 fail2:
205 	kfree(otg_desc[0]);
206 	otg_desc[0] = NULL;
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 	kfree(otg_desc[0]);
223 	otg_desc[0] = NULL;
224 
225 	return 0;
226 }
227 
228 static struct usb_composite_driver cdc_driver = {
229 	.name		= "g_cdc",
230 	.dev		= &device_desc,
231 	.strings	= dev_strings,
232 	.max_speed	= USB_SPEED_HIGH,
233 	.bind		= cdc_bind,
234 	.unbind		= cdc_unbind,
235 };
236 
237 module_usb_composite_driver(cdc_driver);
238 
239 MODULE_DESCRIPTION(DRIVER_DESC);
240 MODULE_AUTHOR("David Brownell");
241 MODULE_LICENSE("GPL");
242