[G2 Q&A, Help & Troubleshooting] FuzzyTern:
I was trying this to fix a hard-bricked G2 I just recieved:

http://xdaforums.com/showthread.php?t=2582142

The device is in the following state:

No download mode

No recovery mode

Shows qhsusb_bulk in lsusb -v

I don't know much more about it (e.g. I don't know if it was rooted or what type of ROM was on it).

I need to unplug the battery by removing the back cover to have a chance to reboot it. The first boot after that it shows the LG logo, then a blank screen (back lit but no text).

(UPDATE: Pressing the power button 8 seconds also reboots the phone without having to unplug the battery).

When I wire it up to my Arch Linux computer here is what the command `dmesg` shows:

[ 3693.728255] usb 1-2: new high-speed USB device number 93 using xhci_hcd
[ 3693.901772] usb 1-2: config 1 has an invalid interface number: 20 but max is 1
[ 3693.901784] usb 1-2: config 1 has no interface number 1
[ 3693.903319] usb-storage 1-2:1.20: USB Mass Storage device detected
[ 3693.903868] scsi host843: usb-storage 1-2:1.20
[ 3694.905067] scsi 843:0:0:0: Direct-Access Qualcomm MMC Storage 1.00 PQ: 0 ANSI: 2
[ 3694.906568] sd 843:0:0:0: [sdb] 30777344 512-byte logical blocks: (15.7 GB/14.6 GiB)
[ 3694.906872] sd 843:0:0:0: [sdb] Write Protect is off
[ 3694.906883] sd 843:0:0:0: [sdb] Mode Sense: 0f 0e 00 00
[ 3694.907373] sd 843:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 3694.919101] sdb: sdb1 sdb2 sdb3 sdb4 sdb5 sdb6 sdb7 sdb8 sdb9 sdb10 sdb11 sdb12 sdb13 sdb14 sdb15 sdb16 sdb17 sdb18 sdb19 sdb20 sdb21 sdb22 sdb23 sdb24 sdb25 sdb26 sdb27 sdb28 sdb29 sdb30 sdb31 sdb32 sdb33 sdb34 sdb35 sdb36
[ 3694.923664] sd 843:0:0:0: [sdb] Attached SCSI disk
[ 3695.061360] usb 1-2: USB disconnect, device number 93
[ 3695.065521] sd 843:0:0:0: [sdb] Synchronizing SCSI cache
[ 3695.065552] sd 843:0:0:0: [sdb]
[ 3695.065554] Result: hostbyte=0x01 driverbyte=0x00
[ 3695.065557] sd 843:0:0:0: [sdb] CDB:
[ 3695.065558] cdb[0]=0x28: 28 00
[ 3695.065562] sd 843:0:0:0: [sdb]
[ 3695.065563] Result: hostbyte=0x01 driverbyte=0x00
[ 3695.065565] sd 843:0:0:0: [sdb] CDB:
[ 3695.065566] cdb[0]=0x28:
[ 3695.065567] 00 00 00
[ 3695.065569] 28
[ 3695.065571] 00
[ 3695.065571] 00
[ 3695.065572] 00
[ 3695.065573] 01
[ 3695.065573] 70
[ 3695.065574] 00
[ 3695.065574] 00
[ 3695.065575] 90
[ 3695.065576] 00

[ 3695.065578] end_request: I/O error, dev sdb, sector 368
[ 3695.065579] 80 00 00 f0 00
[ 3695.065582] quiet_error: 134 callbacks suppressed
[ 3695.065583] Buffer I/O error on device sdb, logical block 46

[ 3695.065586] Buffer I/O error on device sdb, logical block 47
[ 3695.065587] Buffer I/O error on device sdb, logical block 48
[ 3695.065589] end_request: I/O error, dev sdb, sector 128
[ 3695.065590] Buffer I/O error on device sdb, logical block 16
[ 3695.065592] Buffer I/O error on device sdb, logical block 49
[ 3695.065594] Buffer I/O error on device sdb, logical block 17
[ 3695.065595] Buffer I/O error on device sdb, logical block 50
[ 3695.065597] Buffer I/O error on device sdb, logical block 51
[ 3695.065598] Buffer I/O error on device sdb, logical block 52
[ 3695.065599] Buffer I/O error on device sdb, logical block 18
[ 3695.065633] sd 843:0:0:0: [sdb]
[ 3695.065636] Result: hostbyte=0x01 driverbyte=0x00
[ 3695.750741] usb 1-2: new high-speed USB device number 94 using xhci_hcd
[ 3695.924146] usb 1-2: config 1 has an invalid interface number: 20 but max is 1
[ 3695.924151] usb 1-2: config 1 has no interface number 1
...

Note the "config 1 has an invalid interface number: 20 but max is 1" error, and all the Buffer I/O errors.

Here is the relevant section of `lsusb -v`

Bus 001 Device 054: ID 05c6:9006 Qualcomm, Inc.
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x05c6 Qualcomm, Inc.
idProduct 0x9006
bcdDevice 0.00
iManufacturer 1 LG Electronics Inc.

iProduct 2 QHSUSB__BULK
iSerial 3 1234567890ABCDEF
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 55
bNumInterfaces 2
bConfigurationValue 1
iConfiguration 0
bmAttributes 0x80
(Bus Powered)
MaxPower 2mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 255 Vendor Specific Class
bInterfaceSubClass 255 Vendor Specific Subclass
bInterfaceProtocol 255 Vendor Specific Protocol
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x01 EP 1 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 20
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 8 Mass Storage
bInterfaceSubClass 6 SCSI
bInterfaceProtocol 80 Bulk-Only
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x82 EP 2 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Device Status: 0x0000
(Bus Powered)

Is there anything that could be done to fix these Buffer I/O errors so I can mount the phone (and continue with the FIX tutorial posted above)?

Anyone able to shed some lights on the meaning of these lines would be of great help in my quest of learning how to unbrick my phone.

Note: when connected to the computer the blank screen goes in a repeating cycle of being back lit for 1 second then no backlights for 1 second. The cycle stops (with backlights) when unplugging the phone.