greybus: interface: fix power_state documentation

Reword the power_state attribute documentation to make it clear that an
attempt to boot and possibly enumerate an interface is made when writing
"on" to the file, and that on errors the interface will again be powered
down.

Drop the incorrect claim that writing the currently read value has no
effect, since no such guarantees can be made (e.g. several writers may
be sleeping on the interface mutex).

Also fix some minor language issues.

Reviewed-by: Sandeep Patil <sspatil@google.com>
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Reviewed-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Patrick Titiano <ptitiano@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

diff --git a/drivers/staging/greybus/Documentation/sysfs-bus-greybus b/drivers/staging/greybus/Documentation/sysfs-bus-greybus
index 62d03af..e202eac 100644 (file)
--- a/drivers/staging/greybus/Documentation/sysfs-bus-greybus
+++ b/drivers/staging/greybus/Documentation/sysfs-bus-greybus
@@ -102,17 +102,18 @@ Date:             March 2016
 KernelVersion: 4.XX
 Contact:       Greg Kroah-Hartman <greg@kroah.com>
 Description:
-               This reflects the power state of a Greybus Interface. If the
-               value read from it is "on", then power is currently supplied to
-               the Interface. Otherwise this will read "off" and the power is
-               currently not supplied to the Interface.
+               This file reflects the power state of a Greybus interface. If
+               the value read from it is "on", then power is currently
+               supplied to the interface. Otherwise it will read "off" and
+               power is currently not supplied to the interface.
 
                If the value read is "off", then writing "on" (or '1', 'y',
-               'Y') to it will enable power to the Interface. If the value
-               read is "on", then writing "off" (or '0', 'n', 'N') to it will
-               disable power to the Interface.
+               'Y') to this file will enable power to the interface and an
+               attempt to boot and possibly enumerate it will be made. Note
+               that on errors, the interface will again be powered down.
 
-               Writing the currently read value to it has no effect.
+               If the value read is "on", then writing "off" (or '0', 'n',
+               'N') to this file will power down the interface.
 
 What:          /sys/bus/greybus/devices/N-M.I/product_id
 Date:          October 2015