On Wed, Apr 21, 2010 at 12:18:51PM -0400, Martin K. Petersen wrote: > >>>>> "Alan" == Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> writes: > > I'm guessing Doug is out today because he didn't forward the note > below. Just passing the info along... > > > >> It is needed by the transport protocol(s). > > Alan> I don't understand; can you explain more fully? Which transport > Alan> protocol(s) need to use the Sector Count? The USB transport > Alan> protocol doesn't; it encodes the transfer length in a wrapper. > Alan> The bridge chip should interpret the wrapper instead of looking > Alan> inside the SAT command. > > Doug posted to the T10 list and here's what Jim Hatfield from Seagate > responded: > > For ATA (SATA or PATA), the Count field should NEVER be zero, > because neither interface supports zero-length data transfer for > any protocol (dma, pio, etc). > > In ATA, 'N/A' is defined the way it is because there are some > ancient implementations for which there are vendor specific > differences. So, if Jim is correct, then this may not be a bug in the Buffalo device? Or is the phase error in the status of the CSW still an incorrect response after a stall on what the device thinks is an invalid command? Sarah Sharp -- 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
