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UMASS(4)		     Kernel Interfaces Manual			UMASS(4)

NAME
     umass -- USB Mass Storage Devices driver

SYNOPSIS
     device da
     device scbus
     device pass
     device usb
     device umass

     In loader.conf(5):
     umass_load

DESCRIPTION
     The  umass  driver provides support for Mass Storage devices that attach to
     the USB interface.

     If the appropriate hardware is detected, the driver will be loaded automat-
     ically by devmatch(8).  To load the driver manually at boot time,	use  the
     umass_load command at the loader(8) prompt, or add it to loader.conf(5).

     To  use  the driver in a custom kernel, usb(4) and at least one of uhci(4),
     ohci(4), ehci(4), or xhci(4) must be configured in the  kernel.   Addition-
     ally,  since umass uses the SCSI subsystem and sometimes acts as a SCSI de-
     vice, it requires da(4) and scbus(4) to be included in the kernel.

HARDWARE
     The umass driver supports USB Mass Storage devices such as:

     *	 USB thumb drives
     *	 USB hard disk drives
     *	 USB floppy drives

EXAMPLES
     Rescan all slots on a multi-slot flash reader, where the slots map to sepa-
     rate LUNs on a single SCSI ID:

	   camcontrol rescan 0:0:0
	   camcontrol rescan 0:0:1
	   camcontrol rescan 0:0:2
	   camcontrol rescan 0:0:3

     Typically only the first slot will be enabled at boot time.   This  assumes
     that the flash reader is the first SCSI bus in the system and has 4 slots.

SEE ALSO
     cfumass(4), ehci(4), ohci(4), uhci(4), usb(4), xhci(4), camcontrol(8)

HISTORY
     The umass driver appeared in FreeBSD 4.3.

AUTHORS
     The  umass  driver  was written by MAEKAWA Masahide <bishop@rr.iij4u.or.jp>
     and Nick Hibma <n_hibma@FreeBSD.org>.

     This manual page was written by Nick Hibma <n_hibma@FreeBSD.org>.

FreeBSD ports 15.1		 October 9, 2025			UMASS(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=umass&sektion=4&manpath=FreeBSD+15.1-RELEASE+and+Ports>

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