1/*
2 * USB LED driver - 1.1
3 *
4 * Copyright (C) 2004 Greg Kroah-Hartman (greg@kroah.com)
5 *
6 *	This program is free software; you can redistribute it and/or
7 *	modify it under the terms of the GNU General Public License as
8 *	published by the Free Software Foundation, version 2.
9 *
10 */
11
12#include <linux/kernel.h>
13#include <linux/errno.h>
14#include <linux/init.h>
15#include <linux/slab.h>
16#include <linux/module.h>
17#include <linux/usb.h>
18
19
20#define DRIVER_AUTHOR "Greg Kroah-Hartman, greg@kroah.com"
21#define DRIVER_DESC "USB LED Driver"
22
23#define VENDOR_ID	0x0fc5
24#define PRODUCT_ID	0x1223
25
26/* table of devices that work with this driver */
27static struct usb_device_id id_table [] = {
28	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
29	{ },
30};
31MODULE_DEVICE_TABLE (usb, id_table);
32
33struct usb_led {
34	struct usb_device *	udev;
35	unsigned char		blue;
36	unsigned char		red;
37	unsigned char		green;
38};
39
40#define BLUE	0x04
41#define RED	0x02
42#define GREEN	0x01
43static void change_color(struct usb_led *led)
44{
45	int retval;
46	unsigned char color = 0x07;
47	unsigned char *buffer;
48
49	buffer = kmalloc(8, GFP_KERNEL);
50	if (!buffer) {
51		dev_err(&led->udev->dev, "out of memory\n");
52		return;
53	}
54
55	if (led->blue)
56		color &= ~(BLUE);
57	if (led->red)
58		color &= ~(RED);
59	if (led->green)
60		color &= ~(GREEN);
61	dev_dbg(&led->udev->dev,
62		"blue = %d, red = %d, green = %d, color = %.2x\n",
63		led->blue, led->red, led->green, color);
64
65	retval = usb_control_msg(led->udev,
66				usb_sndctrlpipe(led->udev, 0),
67				0x12,
68				0xc8,
69				(0x02 * 0x100) + 0x0a,
70				(0x00 * 0x100) + color,
71				buffer,
72				8,
73				2000);
74	if (retval)
75		dev_dbg(&led->udev->dev, "retval = %d\n", retval);
76	kfree(buffer);
77}
78
79#define show_set(value)	\
80static ssize_t show_##value(struct device *dev, struct device_attribute *attr, char *buf)		\
81{									\
82	struct usb_interface *intf = to_usb_interface(dev);		\
83	struct usb_led *led = usb_get_intfdata(intf);			\
84									\
85	return sprintf(buf, "%d\n", led->value);			\
86}									\
87static ssize_t set_##value(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)	\
88{									\
89	struct usb_interface *intf = to_usb_interface(dev);		\
90	struct usb_led *led = usb_get_intfdata(intf);			\
91	int temp = simple_strtoul(buf, NULL, 10);			\
92									\
93	led->value = temp;						\
94	change_color(led);						\
95	return count;							\
96}									\
97static DEVICE_ATTR(value, S_IWUGO | S_IRUGO, show_##value, set_##value);
98show_set(blue);
99show_set(red);
100show_set(green);
101
102static int led_probe(struct usb_interface *interface, const struct usb_device_id *id)
103{
104	struct usb_device *udev = interface_to_usbdev(interface);
105	struct usb_led *dev = NULL;
106	int retval = -ENOMEM;
107
108	dev = kzalloc(sizeof(struct usb_led), GFP_KERNEL);
109	if (dev == NULL) {
110		dev_err(&interface->dev, "Out of memory\n");
111		goto error_mem;
112	}
113
114	dev->udev = usb_get_dev(udev);
115
116	usb_set_intfdata (interface, dev);
117
118	retval = device_create_file(&interface->dev, &dev_attr_blue);
119	if (retval)
120		goto error;
121	retval = device_create_file(&interface->dev, &dev_attr_red);
122	if (retval)
123		goto error;
124	retval = device_create_file(&interface->dev, &dev_attr_green);
125	if (retval)
126		goto error;
127
128	dev_info(&interface->dev, "USB LED device now attached\n");
129	return 0;
130
131error:
132	device_remove_file(&interface->dev, &dev_attr_blue);
133	device_remove_file(&interface->dev, &dev_attr_red);
134	device_remove_file(&interface->dev, &dev_attr_green);
135	usb_set_intfdata (interface, NULL);
136	usb_put_dev(dev->udev);
137	kfree(dev);
138error_mem:
139	return retval;
140}
141
142static void led_disconnect(struct usb_interface *interface)
143{
144	struct usb_led *dev;
145
146	dev = usb_get_intfdata (interface);
147	usb_set_intfdata (interface, NULL);
148
149	device_remove_file(&interface->dev, &dev_attr_blue);
150	device_remove_file(&interface->dev, &dev_attr_red);
151	device_remove_file(&interface->dev, &dev_attr_green);
152
153	usb_put_dev(dev->udev);
154
155	kfree(dev);
156
157	dev_info(&interface->dev, "USB LED now disconnected\n");
158}
159
160static struct usb_driver led_driver = {
161	.name =		"usbled",
162	.probe =	led_probe,
163	.disconnect =	led_disconnect,
164	.id_table =	id_table,
165};
166
167static int __init usb_led_init(void)
168{
169	int retval = 0;
170
171	retval = usb_register(&led_driver);
172	if (retval)
173		err("usb_register failed. Error number %d", retval);
174	return retval;
175}
176
177static void __exit usb_led_exit(void)
178{
179	usb_deregister(&led_driver);
180}
181
182module_init (usb_led_init);
183module_exit (usb_led_exit);
184
185MODULE_AUTHOR(DRIVER_AUTHOR);
186MODULE_DESCRIPTION(DRIVER_DESC);
187MODULE_LICENSE("GPL");
188