drivers/usb/misc/usbled.c

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