dmatest: return actual state in 'run' file

The following command should return actual state of the test.
	% cat /sys/kernel/debug/dmatest/run

To wait for test done the user may perform a busy loop that checks the state.
	% while [ $(cat /sys/kernel/debug/dmatest/run) = "Y" ]
	> do
	> 	echo -n "."
	> 	sleep 1
	> done
	> echo

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/Documentation/dmatest.txt b/Documentation/dmatest.txt
index 9a90729bdee6..3e17b55a8ba3 100644
--- a/Documentation/dmatest.txt
+++ b/Documentation/dmatest.txt
@@ -36,6 +36,18 @@ in the original code.
 
 Note that running a new test will stop any in progress test.
 
+The following command should return actual state of the test.
+        % cat /sys/kernel/debug/dmatest/run
+
+To wait for test done the user may perform a busy loop that checks the state.
+
+        % while [ $(cat /sys/kernel/debug/dmatest/run) = "Y" ]
+        > do
+        >       echo -n "."
+        >       sleep 1
+        > done
+        > echo
+
         Part 3 - When built-in in the kernel...
 
 The module parameters that is supplied to the kernel command line will be used