LXR linux/drivers/usb/misc/isight

   1/*
   2 * Driver for loading USB isight firmware
   3 *
   4 * Copyright (C) 2008 Matthew Garrett <mjg@redhat.com>
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License as published by the Free
   8 * Software Foundation, version 2.
   9 *
  10 * The USB isight cameras in recent Apples are roughly compatible with the USB
  11 * video class specification, and can be driven by uvcvideo. However, they
  12 * need firmware to be loaded beforehand. After firmware loading, the device
  13 * detaches from the USB bus and reattaches with a new device ID. It can then
  14 * be claimed by the uvc driver.
  15 *
  16 * The firmware is non-free and must be extracted by the user. Tools to do this
  17 * are available at http://bersace03.free.fr/ift/
  18 *
  19 * The isight firmware loading was reverse engineered by Johannes Berg
  20 * <johannes@sipsolutions.de>, and this driver is based on code by Ronald
  21 * Bultje <rbultje@ronald.bitfreak.net>
  22 */
  23
  24#include <linux/usb.h>
  25#include <linux/firmware.h>
  26#include <linux/errno.h>
  27#include <linux/module.h>
  28
  29static struct usb_device_id id_table[] = {
  30        {USB_DEVICE(0x05ac, 0x8300)},
  31        {},
  32};
  33
  34MODULE_DEVICE_TABLE(usb, id_table);
  35
  36static int isight_firmware_load(struct usb_interface *intf,
  37                                const struct usb_device_id *id)
  38{
  39        struct usb_device *dev = interface_to_usbdev(intf);
  40        int llen, len, req, ret = 0;
  41        const struct firmware *firmware;
  42        unsigned char *buf = kmalloc(50, GFP_KERNEL);
  43        unsigned char data[4];
  44        const u8 *ptr;
  45
  46        if (!buf)
  47                return -ENOMEM;
  48
  49        if (request_firmware(&firmware, "isight.fw", &dev->dev) != 0) {
  50                printk(KERN_ERR "Unable to load isight firmware\n");
  51                ret = -ENODEV;
  52                goto out;
  53        }
  54
  55        ptr = firmware->data;
  56
  57        if (usb_control_msg
  58            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, "\1", 1,
  59             300) != 1) {
  60                printk(KERN_ERR
  61                       "Failed to initialise isight firmware loader\n");
  62                ret = -ENODEV;
  63                goto out;
  64        }
  65
  66        while (ptr+4 <= firmware->data+firmware->size) {
  67                memcpy(data, ptr, 4);
  68                len = (data[0] << 8 | data[1]);
  69                req = (data[2] << 8 | data[3]);
  70                ptr += 4;
  71
  72                if (len == 0x8001)
  73                        break;  /* success */
  74                else if (len == 0)
  75                        continue;
  76
  77                for (; len > 0; req += 50) {
  78                        llen = min(len, 50);
  79                        len -= llen;
  80                        if (ptr+llen > firmware->data+firmware->size) {
  81                                printk(KERN_ERR
  82                                       "Malformed isight firmware");
  83                                ret = -ENODEV;
  84                                goto out;
  85                        }
  86                        memcpy(buf, ptr, llen);
  87
  88                        ptr += llen;
  89
  90                        if (usb_control_msg
  91                            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, req, 0,
  92                             buf, llen, 300) != llen) {
  93                                printk(KERN_ERR
  94                                       "Failed to load isight firmware\n");
  95                                ret = -ENODEV;
  96                                goto out;
  97                        }
  98
  99                }
 100        }
 101
 102        if (usb_control_msg
 103            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, "\0", 1,
 104             300) != 1) {
 105                printk(KERN_ERR "isight firmware loading completion failed\n");
 106                ret = -ENODEV;
 107        }
 108
 109out:
 110        kfree(buf);
 111        release_firmware(firmware);
 112        return ret;
 113}
 114
 115static void isight_firmware_disconnect(struct usb_interface *intf)
 116{
 117}
 118
 119static struct usb_driver isight_firmware_driver = {
 120        .name = "isight_firmware",
 121        .probe = isight_firmware_load,
 122        .disconnect = isight_firmware_disconnect,
 123        .id_table = id_table,
 124};
 125
 126static int __init isight_firmware_init(void)
 127{
 128        return usb_register(&isight_firmware_driver);
 129}
 130
 131static void __exit isight_firmware_exit(void)
 132{
 133        usb_deregister(&isight_firmware_driver);
 134}
 135
 136module_init(isight_firmware_init);
 137module_exit(isight_firmware_exit);
 138
 139MODULE_LICENSE("GPL");
 140MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
 141