don't whine about trigger already existing during restart

diff --git a/startup b/startup
index bfbb21e4f84d596b85fe9714d6f28ec92734de85..714e6bc7372235fb8c3f5f84005ccc7d1f5b4c0d 100755 (executable)
--- a/startup
+++ b/startup
@@ -6,7 +6,7 @@
 /usr/share/quantimotor/enable_ads.py
 
 # set up sampling trigger based on kernel high resolution timer
-mkdir /sys/kernel/config/iio/triggers/hrtimer/instance1
+mkdir -p /sys/kernel/config/iio/triggers/hrtimer/instance1
 echo instance1 > /sys/bus/iio/devices/iio\:device0/trigger/current_trigger
 echo 1000 > /sys/bus/iio/devices/trigger0/sampling_frequency