xref: /openbmc/linux/drivers/usb/gadget/legacy/hid.c (revision 3c6a73cc)
1 /*
2  * hid.c -- HID Composite driver
3  *
4  * Based on multi.c
5  *
6  * Copyright (C) 2010 Fabien Chouteau <fabien.chouteau@barco.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  */
13 
14 
15 #include <linux/kernel.h>
16 #include <linux/platform_device.h>
17 #include <linux/list.h>
18 #include <linux/module.h>
19 #include <linux/usb/composite.h>
20 
21 #include "gadget_chips.h"
22 #define DRIVER_DESC		"HID Gadget"
23 #define DRIVER_VERSION		"2010/03/16"
24 
25 /*-------------------------------------------------------------------------*/
26 
27 #define HIDG_VENDOR_NUM		0x0525	/* XXX NetChip */
28 #define HIDG_PRODUCT_NUM	0xa4ac	/* Linux-USB HID 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_hid.c"
40 
41 
42 struct hidg_func_node {
43 	struct list_head node;
44 	struct hidg_func_descriptor *func;
45 };
46 
47 static LIST_HEAD(hidg_func_list);
48 
49 /*-------------------------------------------------------------------------*/
50 USB_GADGET_COMPOSITE_OPTIONS();
51 
52 static struct usb_device_descriptor device_desc = {
53 	.bLength =		sizeof device_desc,
54 	.bDescriptorType =	USB_DT_DEVICE,
55 
56 	.bcdUSB =		cpu_to_le16(0x0200),
57 
58 	/* .bDeviceClass =		USB_CLASS_COMM, */
59 	/* .bDeviceSubClass =	0, */
60 	/* .bDeviceProtocol =	0, */
61 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
62 	.bDeviceSubClass =	0,
63 	.bDeviceProtocol =	0,
64 	/* .bMaxPacketSize0 = f(hardware) */
65 
66 	/* Vendor and product id can be overridden by module parameters.  */
67 	.idVendor =		cpu_to_le16(HIDG_VENDOR_NUM),
68 	.idProduct =		cpu_to_le16(HIDG_PRODUCT_NUM),
69 	/* .bcdDevice = f(hardware) */
70 	/* .iManufacturer = DYNAMIC */
71 	/* .iProduct = DYNAMIC */
72 	/* NO SERIAL NUMBER */
73 	.bNumConfigurations =	1,
74 };
75 
76 static struct usb_otg_descriptor otg_descriptor = {
77 	.bLength =		sizeof otg_descriptor,
78 	.bDescriptorType =	USB_DT_OTG,
79 
80 	/* REVISIT SRP-only hardware is possible, although
81 	 * it would not be called "OTG" ...
82 	 */
83 	.bmAttributes =		USB_OTG_SRP | USB_OTG_HNP,
84 };
85 
86 static const struct usb_descriptor_header *otg_desc[] = {
87 	(struct usb_descriptor_header *) &otg_descriptor,
88 	NULL,
89 };
90 
91 
92 /* string IDs are assigned dynamically */
93 static struct usb_string strings_dev[] = {
94 	[USB_GADGET_MANUFACTURER_IDX].s = "",
95 	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
96 	[USB_GADGET_SERIAL_IDX].s = "",
97 	{  } /* end of list */
98 };
99 
100 static struct usb_gadget_strings stringtab_dev = {
101 	.language	= 0x0409,	/* en-us */
102 	.strings	= strings_dev,
103 };
104 
105 static struct usb_gadget_strings *dev_strings[] = {
106 	&stringtab_dev,
107 	NULL,
108 };
109 
110 
111 
112 /****************************** Configurations ******************************/
113 
114 static int __init do_config(struct usb_configuration *c)
115 {
116 	struct hidg_func_node *e;
117 	int func = 0, status = 0;
118 
119 	if (gadget_is_otg(c->cdev->gadget)) {
120 		c->descriptors = otg_desc;
121 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
122 	}
123 
124 	list_for_each_entry(e, &hidg_func_list, node) {
125 		status = hidg_bind_config(c, e->func, func++);
126 		if (status)
127 			break;
128 	}
129 
130 	return status;
131 }
132 
133 static struct usb_configuration config_driver = {
134 	.label			= "HID Gadget",
135 	.bConfigurationValue	= 1,
136 	/* .iConfiguration = DYNAMIC */
137 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
138 };
139 
140 /****************************** Gadget Bind ******************************/
141 
142 static int __init hid_bind(struct usb_composite_dev *cdev)
143 {
144 	struct usb_gadget *gadget = cdev->gadget;
145 	struct list_head *tmp;
146 	int status, funcs = 0;
147 
148 	list_for_each(tmp, &hidg_func_list)
149 		funcs++;
150 
151 	if (!funcs)
152 		return -ENODEV;
153 
154 	/* set up HID */
155 	status = ghid_setup(cdev->gadget, funcs);
156 	if (status < 0)
157 		return status;
158 
159 	/* Allocate string descriptor numbers ... note that string
160 	 * contents can be overridden by the composite_dev glue.
161 	 */
162 
163 	status = usb_string_ids_tab(cdev, strings_dev);
164 	if (status < 0)
165 		return status;
166 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
167 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
168 
169 	/* register our configuration */
170 	status = usb_add_config(cdev, &config_driver, do_config);
171 	if (status < 0)
172 		return status;
173 
174 	usb_composite_overwrite_options(cdev, &coverwrite);
175 	dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
176 
177 	return 0;
178 }
179 
180 static int __exit hid_unbind(struct usb_composite_dev *cdev)
181 {
182 	ghid_cleanup();
183 	return 0;
184 }
185 
186 static int __init hidg_plat_driver_probe(struct platform_device *pdev)
187 {
188 	struct hidg_func_descriptor *func = dev_get_platdata(&pdev->dev);
189 	struct hidg_func_node *entry;
190 
191 	if (!func) {
192 		dev_err(&pdev->dev, "Platform data missing\n");
193 		return -ENODEV;
194 	}
195 
196 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
197 	if (!entry)
198 		return -ENOMEM;
199 
200 	entry->func = func;
201 	list_add_tail(&entry->node, &hidg_func_list);
202 
203 	return 0;
204 }
205 
206 static int hidg_plat_driver_remove(struct platform_device *pdev)
207 {
208 	struct hidg_func_node *e, *n;
209 
210 	list_for_each_entry_safe(e, n, &hidg_func_list, node) {
211 		list_del(&e->node);
212 		kfree(e);
213 	}
214 
215 	return 0;
216 }
217 
218 
219 /****************************** Some noise ******************************/
220 
221 
222 static __refdata struct usb_composite_driver hidg_driver = {
223 	.name		= "g_hid",
224 	.dev		= &device_desc,
225 	.strings	= dev_strings,
226 	.max_speed	= USB_SPEED_HIGH,
227 	.bind		= hid_bind,
228 	.unbind		= __exit_p(hid_unbind),
229 };
230 
231 static struct platform_driver hidg_plat_driver = {
232 	.remove		= hidg_plat_driver_remove,
233 	.driver		= {
234 		.owner	= THIS_MODULE,
235 		.name	= "hidg",
236 	},
237 };
238 
239 
240 MODULE_DESCRIPTION(DRIVER_DESC);
241 MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
242 MODULE_LICENSE("GPL");
243 
244 static int __init hidg_init(void)
245 {
246 	int status;
247 
248 	status = platform_driver_probe(&hidg_plat_driver,
249 				hidg_plat_driver_probe);
250 	if (status < 0)
251 		return status;
252 
253 	status = usb_composite_probe(&hidg_driver);
254 	if (status < 0)
255 		platform_driver_unregister(&hidg_plat_driver);
256 
257 	return status;
258 }
259 module_init(hidg_init);
260 
261 static void __exit hidg_cleanup(void)
262 {
263 	platform_driver_unregister(&hidg_plat_driver);
264 	usb_composite_unregister(&hidg_driver);
265 }
266 module_exit(hidg_cleanup);
267