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 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"); 116 117 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_LICENSE("GPL"); 131 MODULE_AUTHOR("Matthew Garrett <mjg@redhat.com>"); 132