start_getty: Over added SERIAL_CONSOLE cause error in userspace log

Error log will be logged into /var/log/message.
Added in more condition checking on the script. Check
/proc/tty/drivers and /proc/tty/driver/*
file system to retrieve active targeted serial.
Only establish getty with active serial in runtime.

[YOCTO #10844]

Reviewed-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Choong YinThong <yin.thong.choong@intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>

diff --git a/meta/recipes-core/sysvinit/sysvinit-inittab/start_getty b/meta/recipes-core/sysvinit/sysvinit-inittab/start_getty
index e3d052a84025729a75d77aa325ac53be505c82df..31b44134338737381eb5c41846e8bb2a1e4e7078 100644 (file)
--- a/meta/recipes-core/sysvinit/sysvinit-inittab/start_getty
+++ b/meta/recipes-core/sysvinit/sysvinit-inittab/start_getty
@@ -1,5 +1,35 @@
 #!/bin/sh
-if [ -c /dev/$2 ]
-then 
-       /sbin/getty -L $1 $2 $3
-fi
+####################################################################################
+# This script is use to automatic start serial console once power up.
+# Script enhancement has been done base on Bug YOCTO 10844.
+# Configuration can be done in meta/conf/machine/*.conf variable SERIAL_CONSOLES.
+# Most of the information is retrieve from /proc virtual filesystem which
+# contain all the runtime system information (eg. system memory, device mount, etc).
+####################################################################################
+
+# Get active serial filename.
+active_serial=$(grep "serial" /proc/tty/drivers | grep -oh "^\s*\S*")
+
+# Re-phrase input parameter from ttyS target index (ttyS1, ttyS2, ttyAMA0, etc).
+runtime_tty=$(echo $2 | grep -oh '[0-9]')
+
+for line in $active_serial; do
+       # File is availability, file content current active serial target index.
+       if [ -e /proc/tty/driver/$line ]
+        then
+               # File content a lot of unknown serial. We use -v to remove all unmatch and get left off.
+               # Tail use to avoid 1st line included into the filter because 1st line is file description.
+               activetty=$(grep -v "unknown" /proc/tty/driver/$line | tail -n +2 | grep -oh "^\s*\S*[0-9]")
+               for active in $activetty; do
+                       # Check if both index is match then proceed to enable the serial console.
+                       if [ $active -eq $runtime_tty ] 
+                       then
+                               if [ -c /dev/$2 ]
+                               then
+                                   /sbin/getty -L $1 $2 $3
+                               fi
+                               break
+                       fi
+               done
+       fi
+done