On Aug 17 Stephen M. Cameron wrote:

What:		/sys/bus/scsi/devices/host*/scsi_host/host*/unchecked_isa_dma
+Date:		February, 2003
+KernelVersion:	Unknown
+Contact:	James Bottomley [off-list ref]
+Description:
+
+What:		/sys/bus/scsi/devices/host*/scsi_host/host*/proc_name
+Date:		March, 2004
+KernelVersion:	Unknown
+Contact:	James Bottomley [off-list ref]
+Description:
+
+What:		/sys/bus/scsi/devices/host*/scsi_host/host*/scan
+Date:		August, 2003
+KernelVersion:	Unknown
+Contact:	James Bottomley [off-list ref]
+Description:
+		Read only integer which indicates whether the host is an
+		ancient ISA device which therefore requires extra bounce
+		buffering.

The last description obviously belongs to unchecked_isa_dma.

scan is a write-only attribute that may or may not initiate a bus rescan,
I suppose.

proc_name is the "name of proc directory" of a driver, if the driver
maintained one; though it seems all drivers provide proc_name
independently of the obsolete proc interface for driver data.
-- 
Stefan Richter
-=====-==-== =--- =--=-
http://arcgraph.de/sr/