The HP ML-350 server has 2 USB sockets (V1.1). When pluging the first Self powered, external 3.5" IDE disk in, it works. When pluging the second Self powered, external 3.5" IDE disk in, it fails. The error is "insuffient available bus power" The disk units are identical. This HAS to be wrong since the units are externally powered. A bit of the log Jun 18 17:01:01 mango ohci_hcd 0000:00:0f.2: OHCI Host Controller Jun 18 17:01:01 mango ohci_hcd 0000:00:0f.2: new USB bus registered, assigned bus number 1 Jun 18 17:01:01 mango ohci_hcd 0000:00:0f.2: irq 11, io mem 0xf5fc0000 Jun 18 17:01:01 mango usb usb1: configuration #1 chosen from 1 choice Jun 18 17:01:01 mango hub 1-0:1.0: USB hub found Jun 18 17:01:01 mango hub 1-0:1.0: 4 ports detected Jun 18 17:01:01 mango usb 1-2: new full speed USB device using ohci_hcd and address 2 Jun 18 17:01:01 mango usb 1-2: configuration #1 chosen from 1 choice Jun 18 17:01:01 mango usb-storage: USB Mass Storage device detected Jun 18 17:01:01 mango usb-storage: -- associate_dev Jun 18 17:01:01 mango usb-storage: Vendor: 0x0dc4, Product: 0x0063, Revision: 0x0001 Jun 18 17:01:01 mango usb-storage: Interface Subclass: 0x06, Protocol: 0x50 Jun 18 17:01:01 mango usb-storage: Transport: Bulk Jun 18 17:01:01 mango usb-storage: Protocol: Transparent SCSI Jun 18 17:01:01 mango scsi0 : SCSI emulation for USB Mass Storage devices Jun 18 17:01:01 mango usb-storage: *** thread sleeping. Jun 18 17:01:01 mango usb-storage: device found at 2 Jun 18 17:01:01 mango usb-storage: waiting for device to settle before scanning Jun 18 17:01:01 mango usb 1-3: new full speed USB device using ohci_hcd and address 3 Jun 18 17:01:01 mango usb 1-3: rejected 1 configuration due to insufficient available bus power Jun 18 17:01:01 mango usb 1-3: no configuration chosen from 1 choice Jun 18 17:01:01 mango usb-storage: usb_stor_control_msg: rq=fe rqtype=a1 value=0000 index=00 len=1 Jun 18 17:01:01 mango usb-storage: GetMaxLUN command result is 1, data is 0 Jun 18 17:01:01 mango usb-storage: queuecommand called --- It then goes on very verbosely to activate the first USB disk as sda. This was never an issue until the USB power management code was fixed in this kernel.
Please attach "lsusb -v" output for both devices (doesn't matter that the kernel rejects one due to power budget, lsusb will still work)
Created attachment 89512 [details] output of lsusb -v with both devices plugged in. As requested. I initially thought both disks were identical. Actually, they both just have blue lights...
Well, lsusb failed to get the info for the first device (the Prolific) - presumably this is the one that was rejected. The other device claims to require up to 2mA of power. It almost certainly requires a lot more. I'm still interested to see how much power the Prolific requires. When you see this message: usb 1-3: rejected 1 configuration due to insufficient available bus power Run this command: echo -n 1 >/sys/bus/usb/devices/1-3/bConfigurationValue Then run "lsusb -v" again and post the results here. By the way, the above command will bypass the power requirements, so you should be able to use your disk.
Thanks, I'll do that this Sunday, when I have access to the machine. --John
Created attachment 89947 [details] updated lsusb -v I see that it claims 510mA. That's odd. Much more than it ought to, but I would think, not enough to kill the host port (2.5" external, USB powered disks take 1000mA on startup)
I believe the problem is that onboard ports have a maximum of 500mA power available. Previously, Linux just ignored the power budget. Now that it is computed and checked, anything which uses more than 500mA will always be rejected.
This is basically a broken device.. you should report it to Prolific and at least for now, use the suggested workaround. Some more info can be found here: http://marc.theaimsgroup.com/?l=linux-usb-devel&m=115185194104984&w=1 I'll write a FAQ entry as suggested.