====== Support Custom Remote Controller ======
<WRAP center round important>
**To support custom remote controller with LIRC, your kernel version should be 3.14.29-56 (2016/04/20) or higher.**
</WRAP>
===== Install package =====
Install **LIRC** package. While installing **lirc**, you will be asked the device type of IR receiver and transmitter. Since we will set up this later by manual, you can select **None**.
<code>
$ sudo apt-get install lirc
</code>
===== LIRC configuration =====
Now you will need to modify **/etc/lirc/hardware.conf** to specify the configuration to run as a daemon.
<code>
$ sudo vi /etc/lirc/hardware.conf
</code>
Specify the kernel driver module and its node to read IR signal.
<code>
  REMOTE_MODULES="meson-ir"
  REMOTE_DRIVER="default"
  REMOTE_DEVICE="/dev/lirc0"
</code>
As well as below to make **lircd** start on boot.
<code>
  START_LIRCD="true"
</code>
In order to apply key event to whole system, enable **Userspace Input Event** while adding **--uinput** as a parameter of **lircd**.
<code>
  REMOTE_LIRCD_ARGS="--uinput"
</code>
All necessary configuration is done, you can simply start the service **lirc** by command line or reboot the device.
<code>
$ sudo service lirc start
</code>
==== Default hardware.conf ====
<file text hardware.conf>
# /etc/lirc/hardware.conf
#
#Chosen Remote Control
REMOTE="None"
REMOTE_MODULES="meson-ir"
REMOTE_DRIVER="default"
REMOTE_DEVICE="/dev/lirc0"
REMOTE_SOCKET=""
REMOTE_LIRCD_CONF=""
REMOTE_LIRCD_ARGS="--uinput"

#Chosen IR Transmitter
TRANSMITTER="None"
TRANSMITTER_MODULES=""
TRANSMITTER_DRIVER=""
TRANSMITTER_DEVICE=""
TRANSMITTER_SOCKET=""
TRANSMITTER_LIRCD_CONF=""
TRANSMITTER_LIRCD_ARGS=""

#Disable kernel support.
#Typically, lirc will disable in-kernel support for ir devices in order to
#handle them internally.  Set to false to prevent lirc from disabling this
#in-kernel support. 
#DISABLE_KERNEL_SUPPORT="true"

#Enable lircd
START_LIRCD="true"

#Don't start lircmd even if there seems to be a good config file
#START_LIRCMD="false"

#Try to load appropriate kernel modules
LOAD_MODULES="true"

# Default configuration files for your hardware if any
LIRCMD_CONF=""

#Forcing noninteractive reconfiguration
#If lirc is to be reconfigured by an external application
#that doesn't have a debconf frontend available, the noninteractive
#frontend can be invoked and set to parse REMOTE and TRANSMITTER
#It will then populate all other variables without any user input
#If you would like to configure lirc via standard methods, be sure
#to leave this set to "false"
FORCE_NONINTERACTIVE_RECONFIGURATION="false"
START_LIRCMD=""
</file>

===== Registering own remote controller =====

<WRAP center round important>
Before runing irrecord, please make sure service lircd should release the node, /dev/lirc0.
<code>
root@odroid64:~# sudo kill `pidof lircd`
</code>
https://forum.odroid.com/viewtopic.php?f=141&t=27593
</WRAP>

**Lirc** package provide a tool, **irrecord**, to help registering the buttons of own remote controller. Once the tool is started, for example, you will be asked to press the buttons and it will analyse the signals of your remote controller like protocol type or headers. After this analysis you can start register the buttons one by one.
<code>
$ sudo irrecord --device /dev/lirc0 lircd.conf
</code>
Once signal analysis is done, you will be asked with the message below to enter the button name to register and press the applicable button. In this step, you can register many buttons as much as you expect to register. If you done, just press enter key on the prompt.
<code>
Please enter the name for the next button (press <ENTER> to finish recording)
</code>
The tool would ask you more steps to finalize and store the configuration file with the below message.
<code>
Successfully written config file.
</code>
For example, if you have done whole steps successfully with Hardkernel's stock remote controller, your will have the configuration file like below very similiary.

Now you must copy the configuration file, **lircd.conf**, to **/etc/lirc/** so that **lirc** service can recognize the button.
<code>
$ sudo cp lircd.conf /etc/lirc/lircd.conf
</code>

===== Test =====
If the **Lirc** daemon is running and drivers are loaded properly, you can test if your remote controller is accepted by the tool **irw**.
<code>
odroid@odroid64:~# irw
000000004db29966 00 KEY_LEFT lircd.conf
000000004db2837c 00 KEY_RIGHT lircd.conf
000000004db253ac 00 KEY_UP lircd.conf
000000004db24bb4 00 KEY_DOWN lircd.conf
000000004db2738c 00 KEY_ENTER lircd.conf
</code>
You can check if the daemon is running properly.
<code>
odroid@odroid64:~$ ps -ax | grep lirc
  678 ?        Ss     0:01 /usr/sbin/lircd --output=/run/lirc/lircd --driver=default --device=/dev/lirc0 --uinput
</code>
As well as necessary drivers are loaded.
<code>
odroid@odroid64:~$ lsmod
Module                      Size    Used by
ir_lirc_codec              4468   3
lirc_dev                     8576   1 ir_lirc_codec
ir_mce_kbd_decoder   2980  0
ir_sanyo_decoder       1515   0
ir_sony_decoder         1553   0
ir_jvc_decoder            1559   0
ir_rc6_decoder           1911   0
ir_rc5_decoder           1543   0
ir_nec_decoder          1687   0
meson_ir                   2927   0
</code>

===== Default lircd configuration for ODROID-C2 =====
Here is the default button configuration for Hardkernel's stock remote controller.
<file text lircd.conf>
begin remote

  name  lircd.conf
  bits           16
  flags SPACE_ENC|CONST_LENGTH
  eps            30
  aeps          100

  header      9000  4500
  one           563  1688
  zero          563   564
  ptrail         563
  pre_data_bits   16
  pre_data       0x4DB2
  repeat      9000 2250
  toggle_bit_mask 0x0
      begin codes
          KEY_LEFT                 0x9966
          KEY_RIGHT               0x837C
          KEY_UP                    0x53AC
          KEY_DOWN               0x4BB4
          KEY_ENTER               0x738C
          KEY_HOME                0x41BE
          KEY_MUTE                 0x11EE
          KEY_MENU                 0xA35C
          KEY_BACK                  0x59A6
          KEY_VOLUMEDOWN    0x817E
          KEY_VOLUMEUP         0x01FE
          KEY_POWER               0x3BC4
      end codes
end remote
</file>

===== GPIO based IR =====

If you want to use your extra IR receiver by connecting to GPIO port (ex. one of expansion connectors), gpio-ir-recv module with LIRC can be used.

<WRAP center round important>
** IR functionality based on GPIO is supported on Ubuntu version 3.14.29-58 (2016/05/18) or higher version. **
</WRAP>

=== Hardware Example ===
The below picture is a sample test environment using a IR receiver module, ROM-WT138LM that is the same module built in ODROID-C2 board.

^ IR Receiver ^ C2 Expansion Net ^ Description ^
|IR|Pin#7 GPIOX.BIT21|IR output  |
|GND|Pin#14 GND|Ground  |
|3V3|Pin#17 3.3V Power| 3.3V Power|

{{:en:c2_gpiobasedir_part_wiki.png?130|}}

{{:en:c2_gpiobasedir_wiki.png?350|}}


=== hardware.conf for GPIO based IR ===

Before module installation, you need to specify LIRC module configuration.

<code>
$ sudo vi /etc/lirc/hardware.conf
</code>

The basic form of hardware.conf is described in the aforementioned 'Default hardware.conf' section of this wiki page, \\
and 'REMOTE_MODULES' must be specified as gpio-ir-recv.

<code>
# REMOTE_MODULES="meson-ir"
REMOTE_MODULES="gpio_ir_recv"
</code>

=== How to install modules and setup GPIO configuration ===

Let's suppose to connect IR output of your extra IR receiver module to Pin '7' of expansion connectors (J2). \\
(Expandsion net name : GPIOX.BIT21, GPIO number : 249)

<code>
$ su
# modprobe gpio-ir-recv
# modprobe gpioplug-ir-recv gpio_nr=249 active_low=1
('service lirc start' will be executed automatically)
</code>

To confirm if the LIRC daemon is running based on gpio-ir-recv, check device nodes and protocol name of ir-keytable.
<code>
# ls /dev/lirc*
/dev/lirc0  /dev/lircd
</code>
<code>
# ir-keytable
Found /sys/class/rc/rc0/ (/dev/input/event5) with:
        Driver gpio-rc-recv, table rc-empty
        Supported protocols: lirc rc-5 jvc sony nec sanyo mce-kbd rc-6 
        Enabled protocols: lirc 
        Name: gpio_ir_recv
        bus: 25, vendor/product: 0001:0001, version: 0x0100
        Repeat delay = 500 ms, repeat period = 125 ms
</code>

=== Check list in case of no available gpioirq bank for gpio-ir-recv ===
When the irqs of gpio-ir-recv are requested normally, you can find the information using /proc/interrupts. \\
There are 8 gpio irq banks on S905 chipset so you need to make sure two available gpio irq banks remain. \\
The irq number of gpio irq bank is from '96' to '103' and you can check if it's normally working as following.

<code>
# cat /proc/interrupts | grep gpio-ir-recv
 96:        191          0          0          0       GIC  96  gpio-ir-recv-irq0
 97:        191          0          0          0       GIC  97  gpio-ir-recv-irq1
</code>

=== lircd.conf with Hardkernel IR remote controller ===
If you use Hardkernel IR remote controller, no modification is needed with the aforementioned default lircd.conf file for ODROID-C2.


===== Known Issue of LIRC on ODROID-C2 =====
During booting, the operation of loading LIRC modules fails frequently, so you can see IR operation doesn't work.

Under this situation, the following message comes and there is no input event from IR.

<code>
# irw
connect: Connection refused
</code>

It seems lirc is stpped by systemd caused by an unknown reason and it causes abnormal termination of lirc process.

We are trying to fix it and you can use one of the following workarounds until we've done it.

=== Workaround (1) ===

Add sleep count at the following point.

**load_modules() of /etc/init.d/lirc**
<code>
modprobe $mod 2> /dev/null || MODULES_MISSING=true**
sleep 1
</code>

<code>
# vi /etc/init.d/lirc
.....
.....
load_modules ()
{
        MODULES_MISSING=false

        log_daemon_msg "Loading LIRC modules"
        for mod in $*; do
                if [ $mod = "udev" ]; then
                        log_end_msg 0
                        log_success_msg "Restarted via udev, don't reload modules"
                        break
                else
                        modprobe $mod 2> /dev/null || MODULES_MISSING=true
                        sleep 1
                fi
        done
        log_end_msg $?

        if $MODULES_MISSING; then
                log_failure_msg "Unable to load LIRC kernel modules. Verify your"
                log_failure_msg "selected kernel modules in /etc/lirc/hardware.conf"
                START_LIRCMD=false
                START_LIRCD=false
        fi
}
</code>

=== Workaround (2) ===
Restart lirc service after booting makes LIRC normal.

<code>
root@odroid64:/home/odroid# irw
connect: Connection refused

root@odroid64:/home/odroid# service lirc restart

root@odroid64:/home/odroid# irw
000000004db2738c 00 KEY_ENTER lircd.conf
000000004db29966 01 KEY_LEFT lircd.conf
000000004db2837c 01 KEY_RIGHT lircd.conf
</code>

You can add auto start daemon as following.

<code>
- auto execution "service lirc restart"

odroid@odroid64:~$ su
root@odroid64:/home/odroid# cd /etc/init.d
root@odroid64:/etc/init.d# vi restartlirc

#!/bin/sh
service lirc restart

root@odroid64:/etc/init.d# chmod 755 restartlirc
root@odroid64:/etc/init.d# cd ../rcS.d
root@odroid64:/etc/rcS.d# ln -s ../init.d/restartlirc S90restartlirc
root@odroid64:/etc/rcS.d# reboot
</code>