On 30/06/2022 18.55, Oliver Neukum wrote:
On 29.06.22 16:30, Alan Stern wrote:
Historically the problem goes the other way: Lots of devices used to
report a total size that was one logical block _larger_ than their
actual capacity. This was caused by the firmware authors
misunderstanding the READ CAPACITY command, which is supposed to return
the block number of the last logical block -- but instead they would
return the total number of logical blocks, which is one higher (since
the first block is number 0).
Nowadays most devices seem to sorted this out. It looks like you found
one that makes the opposite mistake: The value it reports is one less
than the last block number.
It is definitely a bug in the caddy. On the other hand, this bug
probably doesn't affect the rest of the caddy's operations.
Or alternatively, the caddy is marked as quirky by mistake.
In that case we need the descriptors of your device to compare it
to the list of quirky devices. Could you provide "lsusb -v"?
Bus 002 Device 030: ID 0bc2:3330 Seagate RSS LLC Raptor 3.5" USB 3.0
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 3.00
bDeviceClass 0
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 9
idVendor 0x0bc2 Seagate RSS LLC
idProduct 0x3330
bcdDevice 0.16
iManufacturer 1 Seagate
iProduct 2 Raptor 3.5" USB 3.0
iSerial 3 2HC015KJ
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 0x002c
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xc0
Self Powered
MaxPower 96mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 2
bInterfaceClass 8 Mass Storage
bInterfaceSubClass 6 SCSI
bInterfaceProtocol 80 Bulk-Only
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 0x0400 1x 1024 bytes
bInterval 0
bMaxBurst 15
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0400 1x 1024 bytes
bInterval 0
bMaxBurst 15
Regards
Oliver
--
Eyal Lebedinsky (eyal@xxxxxxxxxxxxxx)
