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