Messages in this thread | | | From | Herbert Rosmanith <> | Subject | Re: Q: how to send ATA cmds to USB drive? | Date | Mon, 12 Jun 2006 12:02:41 +0200 (MET DST) |
| |
> the userland program looks like this: > > memset(cmd,0,16); > cmd[0]=0x24; > cmd[1]=0x24; > cmd[2]=0x01; > cmd[3]=0x01; ... > if ((i=ioctl(fd,SG_IO,&ioh))==-1) > die("ioctl"); > ... > the data really sent is "0x24 0x04 0x01 0x01", which means that 0x20 gets > cleared in byte 2 (for whatever reason). > > do you have any idea why the data is modified and how I can prevent this?
ok, got it:
int scsi_dispatch_cmd(struct scsi_cmnd *cmd) ... /* * If SCSI-2 or lower, store the LUN value in cmnd. */ if (cmd->device->scsi_level <= SCSI_2) { cmd->cmnd[1] = (cmd->cmnd[1] & 0x1f) | (cmd->device->lun << 5 & 0xe0); }
hm. now what .... ? If scsi-2 requires this, and the device is scsi-2 (in fact, cmd->device->scsi_level equals 3, which means SCSI_2) then the device is a violation of the scsi-specs. do you have any suggestion how to fix this (beside from commenting the source)
kind regards, herbert rosmanith
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |