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#include <linux/slab.h>
  29
  30static const struct usb_device_id id_table[] = {
  31        {USB_DEVICE(0x05ac, 0x8300)},
  32        {},
  33};
  34
  35MODULE_DEVICE_TABLE(usb, id_table);
  36
  37static int isight_firmware_load(struct usb_interface *intf,
  38                                const struct usb_device_id *id)
  39{
  40        struct usb_device *dev = interface_to_usbdev(intf);
  41        int llen, len, req, ret = 0;
  42        const struct firmware *firmware;
  43        unsigned char *buf = kmalloc(50, GFP_KERNEL);
  44        unsigned char data[4];
  45        const u8 *ptr;
  46
  47        if (!buf)
  48                return -ENOMEM;
  49
  50        if (request_firmware(&firmware, "isight.fw", &dev->dev) != 0) {
  51                printk(KERN_ERR "Unable to load isight firmware\n");
  52                ret = -ENODEV;
  53                goto out;
  54        }
  55
  56        ptr = firmware->data;
  57
  58        buf[0] = 0x01;
  59        if (usb_control_msg
  60            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, buf, 1,
  61             300) != 1) {
  62                printk(KERN_ERR
  63                       "Failed to initialise isight firmware loader\n");
  64                ret = -ENODEV;
  65                goto out;
  66        }
  67
  68        while (ptr+4 <= firmware->data+firmware->size) {
  69                memcpy(data, ptr, 4);
  70                len = (data[0] << 8 | data[1]);
  71                req = (data[2] << 8 | data[3]);
  72                ptr += 4;
  73
  74                if (len == 0x8001)
  75                        break;  /* success */
  76                else if (len == 0)
  77                        continue;
  78
  79                for (; len > 0; req += 50) {
  80                        llen = min(len, 50);
  81                        len -= llen;
  82                        if (ptr+llen > firmware->data+firmware->size) {
  83                                printk(KERN_ERR
  84                                       "Malformed isight firmware");
  85                                ret = -ENODEV;
  86                                goto out;
  87                        }
  88                        memcpy(buf, ptr, llen);
  89
  90                        ptr += llen;
  91
  92                        if (usb_control_msg
  93                            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, req, 0,
  94                             buf, llen, 300) != llen) {
  95                                printk(KERN_ERR
  96                                       "Failed to load isight firmware\n");
  97                                ret = -ENODEV;
  98                                goto out;
  99                        }
 100
 101                }
 102        }
 103
 104        buf[0] = 0x00;
 105        if (usb_control_msg
 106            (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, buf, 1,
 107             300) != 1) {
 108                printk(KERN_ERR "isight firmware loading completion failed\n");
 109                ret = -ENODEV;
 110        }
 111
 112out:
 113        kfree(buf);
 114        release_firmware(firmware);
 115        return ret;
 116}
 117
 118MODULE_FIRMWARE("isight.fw");
 119
 120static void isight_firmware_disconnect(struct usb_interface *intf)
 121{
 122}
 123
 124static struct usb_driver isight_firmware_driver = {
 125        .name = "isight_firmware",
 126        .probe = isight_firmware_load,
 127        .disconnect = isight_firmware_disconnect,
 128        .id_table = id_table,
 129};
 130
 131module_usb_driver(isight_firmware_driver);
 132
 133MODULE_LICENSE("GPL");
 134MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
 135