Alan -- You realize that's an okay patch for testing, but not as a final solution, right? 8020 can't accept the short commands; they need to be at least 12 bytes.... Matt On Mon, Oct 24, 2011 at 9:36 AM, Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> wrote: > On Mon, 24 Oct 2011, Matthew Dharm wrote: > >> Alan / Simon -- >> >> If you look at the device descriptors, it reports itself as an >> SFF-8020i device. This kicks-in code to force all commands to >> 12-byte, as (I think) required by 8020i. Of course, for a large >> device like this, you might need 16-byte commands. >> >> This probably needs a protocol override to force it back to >> transparent SCSI mode. Either that, or someone needs to take a longer >> look at the 8020 spec, 8020 devices, and see if there is a way to make >> it work without an override... > > Ooh, you're right. I never noticed. > > I don't know if 8020i is restricted to <= 12 bytes. MMC isn't. But we > may as well accept larger commands too, without padding. (Or maybe > they'll need to be padded to 16 bytes.) And we may as well treat UFI > devices the same way. > > Simon, this patch ought to do the trick. Let us know what happens. > > Alan Stern > > > > Index: usb-3.1/drivers/usb/storage/protocol.c > =================================================================== > --- usb-3.1.orig/drivers/usb/storage/protocol.c > +++ usb-3.1/drivers/usb/storage/protocol.c > @@ -66,9 +66,6 @@ void usb_stor_pad12_command(struct scsi_ > for (; srb->cmd_len<12; srb->cmd_len++) > srb->cmnd[srb->cmd_len] = 0; > > - /* set command length to 12 bytes */ > - srb->cmd_len = 12; > - > /* send the command to the transport layer */ > usb_stor_invoke_transport(srb, us); > } > @@ -86,9 +83,6 @@ void usb_stor_ufi_command(struct scsi_cm > for (; srb->cmd_len<12; srb->cmd_len++) > srb->cmnd[srb->cmd_len] = 0; > > - /* set command length to 12 bytes (this affects the transport layer) */ > - srb->cmd_len = 12; > - > /* XXX We should be constantly re-evaluating the need for these */ > > /* determine the correct data length for these commands */ > > -- Matthew Dharm Maintainer, USB Mass Storage driver for Linux -- 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
