On Tue, 30 Oct 2012, megha dey wrote: > >> From the trace attached,we see that write_10(highlighted command) is > >> taking about 10 seconds,by which time the host is timing out.The host > >> then sends the next test_unit_ready command without getting the status > >> for the previous write.Thus,here we get 2 CBW's without an intervening > >> CSW. > > > > It's not at all clear why the WRITE(10) took so long. Was the FUA bit > > turned on? What happens if you install the mass-storage gadget driver > > with nofua module parameter enabled? > > > > Also, it is clear from this trace that the host is buggy. The > > Bulk-Only spec states that when a command is aborted (as this one was), > > the host must issue a Reset command to the device. > > > > Alan Stern > > > > Hi, > This scenario apears on all standard windows XP PC's and can be > simulated by putting some delay in vfs_write .Also in my case,FUA bit > is not set (nofua is already enabled).This issue only comes with > slower cards (class 2). I don't know what more we can do about this. The host is buggy and the card is too slow for the host. Under those circumstances it doesn't seem possible to avoid a problem. 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
