On Fri, 5 Apr 2013, victor yeo wrote: > Now i insmod g_file_storage gadget with file=/mnt/sd/backing_file, the > SCSI_READ_10 command is still not working properly. What makes you think that? > See the gadget log below. The g_file_storage gadget receives "SCSI > command: Unknown xa1" from the Linux host near the end of the log. 0xA1 is not READ(10); 0x28 is. Why do you think the READ(10) command isn't working properly? > Something is wrong. ... > g_file_storage gadget: bulk-out, length 31: > 00000000: 55 53 42 43 12 00 00 00 00 02 00 00 80 00 0c a1 > 00000010: 08 2e 00 01 00 00 00 00 ec 00 00 00 13 00 00 > g_file_storage gadget: SCSI command: Unknown xa1; Dc=12, Du=0; Hc=12, Hi=512 > g_file_storage gadget: bulk-in, length 0: > g_file_storage gadget: bulk-in set halt > g_file_storage gadget: sending command-failure status > g_file_storage gadget: sense data: SK x05, ASC x20, ASCQ x00; info x0 > g_file_storage gadget: bulk-in, length 13: > 00000000: 55 53 42 53 12 00 00 00 00 02 00 00 01 There's nothing wrong with this. The host is allowed to send commands that the gadget doesn't understand. That's what SK 5, ASC 0x20 means; it tells the host that the gadget didn't understand the previous command. > g_file_storage gadget: ep0-setup, length 8: > 00000000: 80 06 00 01 00 00 40 00 > g_file_storage gadget: get device descriptor But something is definitely wrong here. Before sending this Get-Device-Descriptor request, the host should have done a USB port reset. Either the host isn't performing the reset correctly or else your UDC driver didn't inform g_file_storage when the reset occurred. 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
