On Sun, 28 Feb 2010, Toerless Eckert wrote: > On Sat, Feb 27, 2010 at 10:33:02PM -0500, Alan Stern wrote: > > On Sun, 28 Feb 2010, Toerless Eckert wrote: > > > > > I do have problems with external USB disks, that pretty much lead > > > to them being useless because linux does not recognize them during > > > booting or usb_storage module loading. The only way to recognize > > > them is to plug them into the running system. > > > > > > Drives are Western Digital Elements, 2TB. Kernel is 2.6.29 or 2.6.31 > > > > > > not fully regocnized by linux (tried 2.6.29/2.6.31) when i boot. > > > > This has nothing to do with USB; it is a SCSI matter. The problem is > > that disk probing fails if the drives are spun down when the probe > > begins. You should post your questions on the linux-scsi mailing list. > > Well, that's not quite clear to me. The SATA disk itself is without > power at the time of the problem, If it is without power, how can you expect it to work? > so it is an issue between linux and the > USB/SATA adapter. Linux has nothing to do with supplying power to the disk. At best, all it does is supply power to the USB interface -- and it does that regardless of when you plug the cable in (before boot or after boot). > Itsn't part of what this controller gets also handled > on the linux side by usb_storage.ko ? After all, whether it is a USB > or ATA/USB or SATA/USB command that's eg:missing from the PC to that > adapter, it is something where the adapter needs to react by powering up the > disk. No. All usb-storage does is accept commands from the SCSI layer and send them to the device. If some commands are missing, it isn't usb-storage's fault. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
