isight_firmware.c
/*
* Driver for loading USB isight firmware
*
* Copyright (C) 2008 Matthew Garrett <mjg@redhat.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation, version 2.
*
* The USB isight cameras in recent Apples are roughly compatible with the USB
* video class specification, and can be driven by uvcvideo. However, they
* need firmware to be loaded beforehand. After firmware loading, the device
* detaches from the USB bus and reattaches with a new device ID. It can then
* be claimed by the uvc driver.
*
* The firmware is non-free and must be extracted by the user. Tools to do this
* are available at http://bersace03.free.fr/ift/
*
* The isight firmware loading was reverse engineered by Johannes Berg
* <johannes@sipsolutions.de>, and this driver is based on code by Ronald
* Bultje <rbultje@ronald.bitfreak.net>
*/
#include <linux/usb.h>
#include <linux/firmware.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/slab.h>
static const struct usb_device_id id_table[] = {
{USB_DEVICE(0x05ac, 0x8300)},
{},
};
MODULE_DEVICE_TABLE(usb, id_table);
static int isight_firmware_load(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(intf);
int llen, len, req, ret = 0;
const struct firmware *firmware;
unsigned char *buf = kmalloc(50, GFP_KERNEL);
unsigned char data[4];
const u8 *ptr;
if (!buf)
return -ENOMEM;
if (request_firmware(&firmware, "isight.fw", &dev->dev) != 0) {
printk(KERN_ERR "Unable to load isight firmware\n");
ret = -ENODEV;
goto out;
}
ptr = firmware->data;
if (usb_control_msg
(dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, "\1", 1,
300) != 1) {
printk(KERN_ERR
"Failed to initialise isight firmware loader\n");
ret = -ENODEV;
goto out;
}
while (ptr+4 <= firmware->data+firmware->size) {
memcpy(data, ptr, 4);
len = (data[0] << 8 | data[1]);
req = (data[2] << 8 | data[3]);
ptr += 4;
if (len == 0x8001)
break; /* success */
else if (len == 0)
continue;
for (; len > 0; req += 50) {
llen = min(len, 50);
len -= llen;
if (ptr+llen > firmware->data+firmware->size) {
printk(KERN_ERR
"Malformed isight firmware");
ret = -ENODEV;
goto out;
}
memcpy(buf, ptr, llen);
ptr += llen;
if (usb_control_msg
(dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, req, 0,
buf, llen, 300) != llen) {
printk(KERN_ERR
"Failed to load isight firmware\n");
ret = -ENODEV;
goto out;
}
}
}
if (usb_control_msg
(dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, "\0", 1,
300) != 1) {
printk(KERN_ERR "isight firmware loading completion failed\n");
ret = -ENODEV;
}
out:
kfree(buf);
release_firmware(firmware);
return ret;
}
MODULE_FIRMWARE("isight.fw");
static void isight_firmware_disconnect(struct usb_interface *intf)
{
}
static struct usb_driver isight_firmware_driver = {
.name = "isight_firmware",
.probe = isight_firmware_load,
.disconnect = isight_firmware_disconnect,
.id_table = id_table,
};
static int __init isight_firmware_init(void)
{
return usb_register(&isight_firmware_driver);
}
static void __exit isight_firmware_exit(void)
{
usb_deregister(&isight_firmware_driver);
}
module_init(isight_firmware_init);
module_exit(isight_firmware_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");