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
34struct 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
41static LIST_HEAD(hidg_func_list);
42
43/*-------------------------------------------------------------------------*/
44USB_GADGET_COMPOSITE_OPTIONS();
45
46static struct usb_device_descriptor device_desc = {
47	.bLength =		sizeof device_desc,
48	.bDescriptorType =	USB_DT_DEVICE,
49
50	.bcdUSB =		cpu_to_le16(0x0200),
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
70static const struct usb_descriptor_header *otg_desc[2];
71
72/* string IDs are assigned dynamically */
73static 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
80static struct usb_gadget_strings stringtab_dev = {
81	.language	= 0x0409,	/* en-us */
82	.strings	= strings_dev,
83};
84
85static struct usb_gadget_strings *dev_strings[] = {
86	&stringtab_dev,
87	NULL,
88};
89
90
91
92/****************************** Configurations ******************************/
93
94static 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;
116put:
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
126static 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
135static 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
195free_otg_desc:
196	kfree(otg_desc[0]);
197	otg_desc[0] = NULL;
198put:
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
207static 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
222static 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
242static 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
258static 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
267static struct platform_driver hidg_plat_driver = {
268	.remove		= hidg_plat_driver_remove,
269	.driver		= {
270		.name	= "hidg",
271	},
272};
273
274
275MODULE_DESCRIPTION(DRIVER_DESC);
276MODULE_AUTHOR("Fabien Chouteau, Peter Korsgaard");
277MODULE_LICENSE("GPL");
278
279static 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}
294module_init(hidg_init);
295
296static void __exit hidg_cleanup(void)
297{
298	usb_composite_unregister(&hidg_driver);
299	platform_driver_unregister(&hidg_plat_driver);
300}
301module_exit(hidg_cleanup);
302