rapidio: documentation update for enumeration changes

Update RapidIO documentation to reflect changes made to
enumeration/discovery build configuration and user space triggering
mechanism.

Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Andre van Herk <andre.van.herk@Prodrive.nl>
Cc: Micha Nelissen <micha.nelissen@Prodrive.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/Documentation/rapidio/sysfs.txt b/Documentation/rapidio/sysfs.txt
index 97f71ce575d6..19878179da4c 100644
--- a/Documentation/rapidio/sysfs.txt
+++ b/Documentation/rapidio/sysfs.txt
@@ -88,3 +88,20 @@ that exports additional attributes.
 
 IDT_GEN2:
  errlog - reads contents of device error log until it is empty.
+
+
+5. RapidIO Bus Attributes
+-------------------------
+
+RapidIO bus subdirectory /sys/bus/rapidio implements the following bus-specific
+attribute:
+
+  scan - allows to trigger enumeration discovery process from user space. This
+	 is a write-only attribute. To initiate an enumeration or discovery
+	 process on specific mport device, a user needs to write mport_ID (not
+	 RapidIO destination ID) into this file. The mport_ID is a sequential
+	 number (0 ... RIO_MAX_MPORTS) assigned to the mport device.
+	 For example, for a machine with a single RapidIO controller, mport_ID
+	 for that controller always will be 0.
+	 To initiate RapidIO enumeration/discovery on all available mports
+	 a user must write '-1' (or RIO_MPORT_ANY) into this attribute file.