xref: /linux/drivers/usb/gadget/legacy/hid.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
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 #include <linux/usb/g_hid.h>
21 
22 #include "gadget_chips.h"
23 #define DRIVER_DESC		"HID Gadget"
24 #define DRIVER_VERSION		"2010/03/16"
25 
26 #include "u_hid.h"
27 
28 /*-------------------------------------------------------------------------*/
29 
30 #define HIDG_VENDOR_NUM		0x0525	/* XXX NetChip */
31 #define HIDG_PRODUCT_NUM	0xa4ac	/* Linux-USB HID gadget */
32 
33 /*-------------------------------------------------------------------------*/
34 
35 struct hidg_func_node {
36 	struct usb_function_instance *fi;
37 	struct usb_function *f;
38 	struct list_head node;
39 	struct hidg_func_descriptor *func;
40 };
41 
42 static LIST_HEAD(hidg_func_list);
43 
44 /*-------------------------------------------------------------------------*/
45 USB_GADGET_COMPOSITE_OPTIONS();
46 
47 static struct usb_device_descriptor device_desc = {
48 	.bLength =		sizeof device_desc,
49 	.bDescriptorType =	USB_DT_DEVICE,
50 
51 	.bcdUSB =		cpu_to_le16(0x0200),
52 
53 	/* .bDeviceClass =		USB_CLASS_COMM, */
54 	/* .bDeviceSubClass =	0, */
55 	/* .bDeviceProtocol =	0, */
56 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
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(HIDG_VENDOR_NUM),
63 	.idProduct =		cpu_to_le16(HIDG_PRODUCT_NUM),
64 	/* .bcdDevice = f(hardware) */
65 	/* .iManufacturer = DYNAMIC */
66 	/* .iProduct = DYNAMIC */
67 	/* NO SERIAL NUMBER */
68 	.bNumConfigurations =	1,
69 };
70 
71 static 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 
81 static 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 */
88 static 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 
95 static struct usb_gadget_strings stringtab_dev = {
96 	.language	= 0x0409,	/* en-us */
97 	.strings	= strings_dev,
98 };
99 
100 static struct usb_gadget_strings *dev_strings[] = {
101 	&stringtab_dev,
102 	NULL,
103 };
104 
105 
106 
107 /****************************** Configurations ******************************/
108 
109 static int __init do_config(struct usb_configuration *c)
110 {
111 	struct hidg_func_node *e, *n;
112 	int status = 0;
113 
114 	if (gadget_is_otg(c->cdev->gadget)) {
115 		c->descriptors = otg_desc;
116 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
117 	}
118 
119 	list_for_each_entry(e, &hidg_func_list, node) {
120 		e->f = usb_get_function(e->fi);
121 		if (IS_ERR(e->f))
122 			goto put;
123 		status = usb_add_function(c, e->f);
124 		if (status < 0) {
125 			usb_put_function(e->f);
126 			goto put;
127 		}
128 	}
129 
130 	return 0;
131 put:
132 	list_for_each_entry(n, &hidg_func_list, node) {
133 		if (n == e)
134 			break;
135 		usb_remove_function(c, n->f);
136 		usb_put_function(n->f);
137 	}
138 	return status;
139 }
140 
141 static struct usb_configuration config_driver = {
142 	.label			= "HID Gadget",
143 	.bConfigurationValue	= 1,
144 	/* .iConfiguration = DYNAMIC */
145 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
146 };
147 
148 /****************************** Gadget Bind ******************************/
149 
150 static int __init hid_bind(struct usb_composite_dev *cdev)
151 {
152 	struct usb_gadget *gadget = cdev->gadget;
153 	struct list_head *tmp;
154 	struct hidg_func_node *n, *m;
155 	struct f_hid_opts *hid_opts;
156 	int status, funcs = 0;
157 
158 	list_for_each(tmp, &hidg_func_list)
159 		funcs++;
160 
161 	if (!funcs)
162 		return -ENODEV;
163 
164 	list_for_each_entry(n, &hidg_func_list, node) {
165 		n->fi = usb_get_function_instance("hid");
166 		if (IS_ERR(n->fi)) {
167 			status = PTR_ERR(n->fi);
168 			goto put;
169 		}
170 		hid_opts = container_of(n->fi, struct f_hid_opts, func_inst);
171 		hid_opts->subclass = n->func->subclass;
172 		hid_opts->protocol = n->func->protocol;
173 		hid_opts->report_length = n->func->report_length;
174 		hid_opts->report_desc_length = n->func->report_desc_length;
175 		hid_opts->report_desc = n->func->report_desc;
176 	}
177 
178 
179 	/* Allocate string descriptor numbers ... note that string
180 	 * contents can be overridden by the composite_dev glue.
181 	 */
182 
183 	status = usb_string_ids_tab(cdev, strings_dev);
184 	if (status < 0)
185 		goto put;
186 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
187 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
188 
189 	/* register our configuration */
190 	status = usb_add_config(cdev, &config_driver, do_config);
191 	if (status < 0)
192 		goto put;
193 
194 	usb_composite_overwrite_options(cdev, &coverwrite);
195 	dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
196 
197 	return 0;
198 
199 put:
200 	list_for_each_entry(m, &hidg_func_list, node) {
201 		if (m == n)
202 			break;
203 		usb_put_function_instance(m->fi);
204 	}
205 	return status;
206 }
207 
208 static int __exit hid_unbind(struct usb_composite_dev *cdev)
209 {
210 	struct hidg_func_node *n;
211 
212 	list_for_each_entry(n, &hidg_func_list, node) {
213 		usb_put_function(n->f);
214 		usb_put_function_instance(n->fi);
215 	}
216 	return 0;
217 }
218 
219 static int __init hidg_plat_driver_probe(struct platform_device *pdev)
220 {
221 	struct hidg_func_descriptor *func = dev_get_platdata(&pdev->dev);
222 	struct hidg_func_node *entry;
223 
224 	if (!func) {
225 		dev_err(&pdev->dev, "Platform data missing\n");
226 		return -ENODEV;
227 	}
228 
229 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
230 	if (!entry)
231 		return -ENOMEM;
232 
233 	entry->func = func;
234 	list_add_tail(&entry->node, &hidg_func_list);
235 
236 	return 0;
237 }
238 
239 static int hidg_plat_driver_remove(struct platform_device *pdev)
240 {
241 	struct hidg_func_node *e, *n;
242 
243 	list_for_each_entry_safe(e, n, &hidg_func_list, node) {
244 		list_del(&e->node);
245 		kfree(e);
246 	}
247 
248 	return 0;
249 }
250 
251 
252 /****************************** Some noise ******************************/
253 
254 
255 static __refdata struct usb_composite_driver hidg_driver = {
256 	.name		= "g_hid",
257 	.dev		= &device_desc,
258 	.strings	= dev_strings,
259 	.max_speed	= USB_SPEED_HIGH,
260 	.bind		= hid_bind,
261 	.unbind		= __exit_p(hid_unbind),
262 };
263 
264 static struct platform_driver hidg_plat_driver = {
265 	.remove		= hidg_plat_driver_remove,
266 	.driver		= {
267 		.name	= "hidg",
268 	},
269 };
270 
271 
272 MODULE_DESCRIPTION(DRIVER_DESC);
273 MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
274 MODULE_LICENSE("GPL");
275 
276 static int __init hidg_init(void)
277 {
278 	int status;
279 
280 	status = platform_driver_probe(&hidg_plat_driver,
281 				hidg_plat_driver_probe);
282 	if (status < 0)
283 		return status;
284 
285 	status = usb_composite_probe(&hidg_driver);
286 	if (status < 0)
287 		platform_driver_unregister(&hidg_plat_driver);
288 
289 	return status;
290 }
291 module_init(hidg_init);
292 
293 static void __exit hidg_cleanup(void)
294 {
295 	usb_composite_unregister(&hidg_driver);
296 	platform_driver_unregister(&hidg_plat_driver);
297 }
298 module_exit(hidg_cleanup);
299