apalis-imx8: udev: add symlink to adc raw data

Create symlinks for each supported by Apalis iMX8 ADC channels,
standardizing names as apalis-adcX, according to the Apalis signal names
table.

Related-to: ELB-2839
Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@toradex.com>
(cherry picked from commit a98861ebc9d2a26f458a57f674b53cb81405da64)

1 files changed, 21 insertions, 0 deletions

diff --git a/recipes-core/udev/files/apalis-imx8/toradex-adc.sh b/recipes-core/udev/files/apalis-imx8/toradex-adc.sh
new file mode 100755
index 0000000..fdc5365
--- /dev/null
+++ b/recipes-core/udev/files/apalis-imx8/toradex-adc.sh
@@ -0,0 +1,21 @@
+#!/usr/bin/env sh
+#
+# Called from udev. Compatible to apalis-imx8.
+#
+# Create/remove symlinks to/from the files with raw ain data.
+
+# Map the ADC lines:
+# apalis-adc{0..3} -> DMA.ADC.IN{0,1,2,3}
+LINES=4
+START=0
+
+if [ "$ACTION" = "add" ]; then
+    for idx in `seq 0 $((LINES-1))`; do
+        ln -s "/sys$DEVPATH/in_voltage$((START+idx))_raw" /dev/apalis-ain$idx
+    done
+elif [ "$ACTION" = "remove" ]; then
+    for idx in `seq 0 $((LINES-1))`; do
+        rm -f /dev/apalis-ain$idx
+    done
+fi
+