cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

isight_firmware.c (3214B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Driver for loading USB isight firmware
      4 *
      5 * Copyright (C) 2008 Matthew Garrett <mjg@redhat.com>
      6 *
      7 * The USB isight cameras in recent Apples are roughly compatible with the USB
      8 * video class specification, and can be driven by uvcvideo. However, they
      9 * need firmware to be loaded beforehand. After firmware loading, the device
     10 * detaches from the USB bus and reattaches with a new device ID. It can then
     11 * be claimed by the uvc driver.
     12 *
     13 * The firmware is non-free and must be extracted by the user. Tools to do this
     14 * are available at http://bersace03.free.fr/ift/
     15 *
     16 * The isight firmware loading was reverse engineered by Johannes Berg
     17 * <johannes@sipsolutions.de>, and this driver is based on code by Ronald
     18 * Bultje <rbultje@ronald.bitfreak.net>
     19 */
     20
     21#include <linux/usb.h>
     22#include <linux/firmware.h>
     23#include <linux/errno.h>
     24#include <linux/module.h>
     25#include <linux/slab.h>
     26
     27static const struct usb_device_id id_table[] = {
     28	{USB_DEVICE(0x05ac, 0x8300)},
     29	{},
     30};
     31
     32MODULE_DEVICE_TABLE(usb, id_table);
     33
     34static int isight_firmware_load(struct usb_interface *intf,
     35				const struct usb_device_id *id)
     36{
     37	struct usb_device *dev = interface_to_usbdev(intf);
     38	int llen, len, req, ret = 0;
     39	const struct firmware *firmware;
     40	unsigned char *buf = kmalloc(50, GFP_KERNEL);
     41	unsigned char data[4];
     42	const u8 *ptr;
     43
     44	if (!buf)
     45		return -ENOMEM;
     46
     47	if (request_firmware(&firmware, "isight.fw", &dev->dev) != 0) {
     48		printk(KERN_ERR "Unable to load isight firmware\n");
     49		ret = -ENODEV;
     50		goto out;
     51	}
     52
     53	ptr = firmware->data;
     54
     55	buf[0] = 0x01;
     56	if (usb_control_msg
     57	    (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, buf, 1,
     58	     300) != 1) {
     59		printk(KERN_ERR
     60		       "Failed to initialise isight firmware loader\n");
     61		ret = -ENODEV;
     62		goto out;
     63	}
     64
     65	while (ptr+4 <= firmware->data+firmware->size) {
     66		memcpy(data, ptr, 4);
     67		len = (data[0] << 8 | data[1]);
     68		req = (data[2] << 8 | data[3]);
     69		ptr += 4;
     70
     71		if (len == 0x8001)
     72			break;	/* success */
     73		else if (len == 0)
     74			continue;
     75
     76		for (; len > 0; req += 50) {
     77			llen = min(len, 50);
     78			len -= llen;
     79			if (ptr+llen > firmware->data+firmware->size) {
     80				printk(KERN_ERR
     81				       "Malformed isight firmware");
     82				ret = -ENODEV;
     83				goto out;
     84			}
     85			memcpy(buf, ptr, llen);
     86
     87			ptr += llen;
     88
     89			if (usb_control_msg
     90			    (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, req, 0,
     91			     buf, llen, 300) != llen) {
     92				printk(KERN_ERR
     93				       "Failed to load isight firmware\n");
     94				ret = -ENODEV;
     95				goto out;
     96			}
     97
     98		}
     99	}
    100
    101	buf[0] = 0x00;
    102	if (usb_control_msg
    103	    (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, buf, 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
    115MODULE_FIRMWARE("isight.fw");
    116
    117static void isight_firmware_disconnect(struct usb_interface *intf)
    118{
    119}
    120
    121static struct usb_driver isight_firmware_driver = {
    122	.name = "isight_firmware",
    123	.probe = isight_firmware_load,
    124	.disconnect = isight_firmware_disconnect,
    125	.id_table = id_table,
    126};
    127
    128module_usb_driver(isight_firmware_driver);
    129
    130MODULE_LICENSE("GPL");
    131MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");