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
27 static const struct usb_device_id id_table[] = {
28 {USB_DEVICE(0x05ac, 0x8300)},
29 {},
30 };
31
32 MODULE_DEVICE_TABLE(usb, id_table);
33
isight_firmware_load(struct usb_interface * intf,const struct usb_device_id * id)34 static 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
109 out:
110 kfree(buf);
111 release_firmware(firmware);
112 return ret;
113 }
114
115 MODULE_FIRMWARE("isight.fw");
116
isight_firmware_disconnect(struct usb_interface * intf)117 static void isight_firmware_disconnect(struct usb_interface *intf)
118 {
119 }
120
121 static 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
128 module_usb_driver(isight_firmware_driver);
129
130 MODULE_DESCRIPTION("iSight firmware loading support");
131 MODULE_LICENSE("GPL");
132 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>");
133