Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6
[linux-2.6] / drivers / usb / misc / isight_firmware.c
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
29 static struct usb_device_id id_table[] = {
30         {USB_DEVICE(0x05ac, 0x8300)},
31         {},
32 };
33
34 MODULE_DEVICE_TABLE(usb, id_table);
35
36 static 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         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                 return -ENODEV;
52         }
53
54         ptr = firmware->data;
55
56         if (usb_control_msg
57             (dev, usb_sndctrlpipe(dev, 0), 0xa0, 0x40, 0xe600, 0, "\1", 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                                 kfree(buf);
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
109 out:
110         kfree(buf);
111         release_firmware(firmware);
112         return ret;
113 }
114
115 static void isight_firmware_disconnect(struct usb_interface *intf)
116 {
117 }
118
119 static 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
126 static int __init isight_firmware_init(void)
127 {
128         return usb_register(&isight_firmware_driver);
129 }
130
131 static void __exit isight_firmware_exit(void)
132 {
133         usb_deregister(&isight_firmware_driver);
134 }
135
136 module_init(isight_firmware_init);
137 module_exit(isight_firmware_exit);
138
139 MODULE_LICENSE("GPL");
140 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");