[libgpiod][PATCH 1/1] gpio-tools-test.bats: modify delays in toggle test

[<joe.slater@windriver.com>]

From: Joe Slater <joe.slater@windriver.com>

The test "gpioset: toggle (continuous)" uses fixed delays to test
toggling values.  This is not reliable, so we switch to looking
for transitions from one value to another.

Signed-off-by: Joe Slater <joe.slater@windriver.com>
---
 tools/gpio-tools-test.bats | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/tools/gpio-tools-test.bats b/tools/gpio-tools-test.bats
index adbce94..977d718 100755
--- a/tools/gpio-tools-test.bats
+++ b/tools/gpio-tools-test.bats
@@ -141,6 +141,20 @@ gpiosim_check_value() {
 	[ "$VAL" = "$EXPECTED" ]
 }
 
+gpiosim_wait_value() {
+	local OFFSET=$2
+	local EXPECTED=$3
+	local DEVNAME=${GPIOSIM_DEV_NAME[$1]}
+	local CHIPNAME=${GPIOSIM_CHIP_NAME[$1]}
+
+	for i in {1..10} ; do
+		VAL=$(<$GPIOSIM_SYSFS/$DEVNAME/$CHIPNAME/sim_gpio$OFFSET/value)
+		[ "$VAL" = "$EXPECTED" ] && return
+		sleep 0.1
+	done
+	return 1
+}
+
 gpiosim_cleanup() {
 	for CHIP in ${!GPIOSIM_CHIP_NAME[@]}
 	do
@@ -1567,15 +1581,15 @@ request_release_line() {
 	gpiosim_check_value sim0 4 0
 	gpiosim_check_value sim0 7 0
 
-	sleep 1
-
-	gpiosim_check_value sim0 1 0
+	# sleeping fixed amounts can be unreliable, so we
+	# sync to the toggles
+	#
+	gpiosim_wait_value sim0 1 0
 	gpiosim_check_value sim0 4 1
 	gpiosim_check_value sim0 7 1
 
-	sleep 1
 
-	gpiosim_check_value sim0 1 1
+	gpiosim_wait_value sim0 1 1
 	gpiosim_check_value sim0 4 0
 	gpiosim_check_value sim0 7 0
 }
-- 
2.25.1