xref: /openbmc/linux/drivers/usb/gadget/legacy/hid.c (revision 4f6cce39)
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 #define DRIVER_DESC		"HID Gadget"
23 #define DRIVER_VERSION		"2010/03/16"
24 
25 #include "u_hid.h"
26 
27 /*-------------------------------------------------------------------------*/
28 
29 #define HIDG_VENDOR_NUM		0x0525	/* XXX NetChip */
30 #define HIDG_PRODUCT_NUM	0xa4ac	/* Linux-USB HID gadget */
31 
32 /*-------------------------------------------------------------------------*/
33 
34 struct hidg_func_node {
35 	struct usb_function_instance *fi;
36 	struct usb_function *f;
37 	struct list_head node;
38 	struct hidg_func_descriptor *func;
39 };
40 
41 static LIST_HEAD(hidg_func_list);
42 
43 /*-------------------------------------------------------------------------*/
44 USB_GADGET_COMPOSITE_OPTIONS();
45 
46 static struct usb_device_descriptor device_desc = {
47 	.bLength =		sizeof device_desc,
48 	.bDescriptorType =	USB_DT_DEVICE,
49 
50 	/* .bcdUSB = DYNAMIC */
51 
52 	/* .bDeviceClass =		USB_CLASS_COMM, */
53 	/* .bDeviceSubClass =	0, */
54 	/* .bDeviceProtocol =	0, */
55 	.bDeviceClass =		USB_CLASS_PER_INTERFACE,
56 	.bDeviceSubClass =	0,
57 	.bDeviceProtocol =	0,
58 	/* .bMaxPacketSize0 = f(hardware) */
59 
60 	/* Vendor and product id can be overridden by module parameters.  */
61 	.idVendor =		cpu_to_le16(HIDG_VENDOR_NUM),
62 	.idProduct =		cpu_to_le16(HIDG_PRODUCT_NUM),
63 	/* .bcdDevice = f(hardware) */
64 	/* .iManufacturer = DYNAMIC */
65 	/* .iProduct = DYNAMIC */
66 	/* NO SERIAL NUMBER */
67 	.bNumConfigurations =	1,
68 };
69 
70 static const struct usb_descriptor_header *otg_desc[2];
71 
72 /* string IDs are assigned dynamically */
73 static struct usb_string strings_dev[] = {
74 	[USB_GADGET_MANUFACTURER_IDX].s = "",
75 	[USB_GADGET_PRODUCT_IDX].s = DRIVER_DESC,
76 	[USB_GADGET_SERIAL_IDX].s = "",
77 	{  } /* end of list */
78 };
79 
80 static struct usb_gadget_strings stringtab_dev = {
81 	.language	= 0x0409,	/* en-us */
82 	.strings	= strings_dev,
83 };
84 
85 static struct usb_gadget_strings *dev_strings[] = {
86 	&stringtab_dev,
87 	NULL,
88 };
89 
90 
91 
92 /****************************** Configurations ******************************/
93 
94 static int do_config(struct usb_configuration *c)
95 {
96 	struct hidg_func_node *e, *n;
97 	int status = 0;
98 
99 	if (gadget_is_otg(c->cdev->gadget)) {
100 		c->descriptors = otg_desc;
101 		c->bmAttributes |= USB_CONFIG_ATT_WAKEUP;
102 	}
103 
104 	list_for_each_entry(e, &hidg_func_list, node) {
105 		e->f = usb_get_function(e->fi);
106 		if (IS_ERR(e->f))
107 			goto put;
108 		status = usb_add_function(c, e->f);
109 		if (status < 0) {
110 			usb_put_function(e->f);
111 			goto put;
112 		}
113 	}
114 
115 	return 0;
116 put:
117 	list_for_each_entry(n, &hidg_func_list, node) {
118 		if (n == e)
119 			break;
120 		usb_remove_function(c, n->f);
121 		usb_put_function(n->f);
122 	}
123 	return status;
124 }
125 
126 static struct usb_configuration config_driver = {
127 	.label			= "HID Gadget",
128 	.bConfigurationValue	= 1,
129 	/* .iConfiguration = DYNAMIC */
130 	.bmAttributes		= USB_CONFIG_ATT_SELFPOWER,
131 };
132 
133 /****************************** Gadget Bind ******************************/
134 
135 static int hid_bind(struct usb_composite_dev *cdev)
136 {
137 	struct usb_gadget *gadget = cdev->gadget;
138 	struct list_head *tmp;
139 	struct hidg_func_node *n, *m;
140 	struct f_hid_opts *hid_opts;
141 	int status, funcs = 0;
142 
143 	list_for_each(tmp, &hidg_func_list)
144 		funcs++;
145 
146 	if (!funcs)
147 		return -ENODEV;
148 
149 	list_for_each_entry(n, &hidg_func_list, node) {
150 		n->fi = usb_get_function_instance("hid");
151 		if (IS_ERR(n->fi)) {
152 			status = PTR_ERR(n->fi);
153 			goto put;
154 		}
155 		hid_opts = container_of(n->fi, struct f_hid_opts, func_inst);
156 		hid_opts->subclass = n->func->subclass;
157 		hid_opts->protocol = n->func->protocol;
158 		hid_opts->report_length = n->func->report_length;
159 		hid_opts->report_desc_length = n->func->report_desc_length;
160 		hid_opts->report_desc = n->func->report_desc;
161 	}
162 
163 
164 	/* Allocate string descriptor numbers ... note that string
165 	 * contents can be overridden by the composite_dev glue.
166 	 */
167 
168 	status = usb_string_ids_tab(cdev, strings_dev);
169 	if (status < 0)
170 		goto put;
171 	device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
172 	device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
173 
174 	if (gadget_is_otg(gadget) && !otg_desc[0]) {
175 		struct usb_descriptor_header *usb_desc;
176 
177 		usb_desc = usb_otg_descriptor_alloc(gadget);
178 		if (!usb_desc)
179 			goto put;
180 		usb_otg_descriptor_init(gadget, usb_desc);
181 		otg_desc[0] = usb_desc;
182 		otg_desc[1] = NULL;
183 	}
184 
185 	/* register our configuration */
186 	status = usb_add_config(cdev, &config_driver, do_config);
187 	if (status < 0)
188 		goto free_otg_desc;
189 
190 	usb_composite_overwrite_options(cdev, &coverwrite);
191 	dev_info(&gadget->dev, DRIVER_DESC ", version: " DRIVER_VERSION "\n");
192 
193 	return 0;
194 
195 free_otg_desc:
196 	kfree(otg_desc[0]);
197 	otg_desc[0] = NULL;
198 put:
199 	list_for_each_entry(m, &hidg_func_list, node) {
200 		if (m == n)
201 			break;
202 		usb_put_function_instance(m->fi);
203 	}
204 	return status;
205 }
206 
207 static int hid_unbind(struct usb_composite_dev *cdev)
208 {
209 	struct hidg_func_node *n;
210 
211 	list_for_each_entry(n, &hidg_func_list, node) {
212 		usb_put_function(n->f);
213 		usb_put_function_instance(n->fi);
214 	}
215 
216 	kfree(otg_desc[0]);
217 	otg_desc[0] = NULL;
218 
219 	return 0;
220 }
221 
222 static int hidg_plat_driver_probe(struct platform_device *pdev)
223 {
224 	struct hidg_func_descriptor *func = dev_get_platdata(&pdev->dev);
225 	struct hidg_func_node *entry;
226 
227 	if (!func) {
228 		dev_err(&pdev->dev, "Platform data missing\n");
229 		return -ENODEV;
230 	}
231 
232 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
233 	if (!entry)
234 		return -ENOMEM;
235 
236 	entry->func = func;
237 	list_add_tail(&entry->node, &hidg_func_list);
238 
239 	return 0;
240 }
241 
242 static int hidg_plat_driver_remove(struct platform_device *pdev)
243 {
244 	struct hidg_func_node *e, *n;
245 
246 	list_for_each_entry_safe(e, n, &hidg_func_list, node) {
247 		list_del(&e->node);
248 		kfree(e);
249 	}
250 
251 	return 0;
252 }
253 
254 
255 /****************************** Some noise ******************************/
256 
257 
258 static struct usb_composite_driver hidg_driver = {
259 	.name		= "g_hid",
260 	.dev		= &device_desc,
261 	.strings	= dev_strings,
262 	.max_speed	= USB_SPEED_HIGH,
263 	.bind		= hid_bind,
264 	.unbind		= hid_unbind,
265 };
266 
267 static struct platform_driver hidg_plat_driver = {
268 	.remove		= hidg_plat_driver_remove,
269 	.driver		= {
270 		.name	= "hidg",
271 	},
272 };
273 
274 
275 MODULE_DESCRIPTION(DRIVER_DESC);
276 MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
277 MODULE_LICENSE("GPL");
278 
279 static int __init hidg_init(void)
280 {
281 	int status;
282 
283 	status = platform_driver_probe(&hidg_plat_driver,
284 				hidg_plat_driver_probe);
285 	if (status < 0)
286 		return status;
287 
288 	status = usb_composite_probe(&hidg_driver);
289 	if (status < 0)
290 		platform_driver_unregister(&hidg_plat_driver);
291 
292 	return status;
293 }
294 module_init(hidg_init);
295 
296 static void __exit hidg_cleanup(void)
297 {
298 	usb_composite_unregister(&hidg_driver);
299 	platform_driver_unregister(&hidg_plat_driver);
300 }
301 module_exit(hidg_cleanup);
302