evtest doesn't recognize media key presses

vuckale · 01-25-2021, 10:26 AM

I have Compaq sdm4540ul which is also called Compaq Internet Keyboard. Here is an image of it. http://imgur.com/5d0kUUq

As you can see there is a set of keys in the top row. When I run sudo evtest I see 4 events from this keyboard in dev/input namely:

Code:

/dev/input/event12:	Compaq Compaq Internet Keyboard
/dev/input/event13:	Compaq Compaq Internet Keyboard Consumer Control
/dev/input/event14:	Compaq Compaq Internet Keyboard System Control
/dev/input/event15:	Compaq Compaq Internet Keyboard

Now event12 rocognizes all the keys except the top row, event13 is for the top row, 14 and 15 have KEY_POWER, LED_MAIL etc. which I guess are for the LEDs.

I will post all the output in this pastebin link: https://pastebin.com/NHZj0z2k

In that top row of keys there is 7 keys in the middle that evtest doesn't recognize. Every other key in that top row is recognized.

As I mentioned before, event13 seem to be one for those keys in the top row so I have tried to see if input-kbd 13 sees something that evtest doesn't see and I got this:

Code:

0xc00e9 = 115  # volume up +
0xc00ea = 114  # volume down -
0xc00e2 = 113  # mute
0x10081 = 116  # ???
0x10082 = 142  # ???
0x10083 = 143  # ???
0xc00b5 = 163  # next song
0xc00b6 = 165  # previous song
0xc00b7 = 166  # stop
0xc0183 = 171  # eject
0xc00cd = 164  # play/pause
0xc00e5 = 209  # ???
0xc0192 = 140  # ???
0xc0152 = 240  # ???
0xc0153 = 240  # ???
0xc0154 = 240  # ???
0xc0155 = 240  # ???
0xc00b8 = 161  # ???
0xc0224 = 158  # ???
0xc00e7 = 240  # ???
0xc022a = 156  # ???
0xc02a4 = 240  # ? key
0xc02a5 = 240  # person figure key

Some of the keys do match with ones displayed in evtest for instance 0xc00e9 is the volume up key and I get this in evtest for it:

Code:

Event: time 1611589575.471766, type 4 (EV_MSC), code 4 (MSC_SCAN), value c00e9
Event: time 1611589575.471766, type 1 (EV_KEY), code 115 (KEY_VOLUMEUP), value 1

I wrote in comment what which key represents.

I then tried to remap those key that I couldn't get event for in evtest with the udev. For example lets take 0xc022a = 156. In /etc/udev/hwdb.d/ I made a file 70-keyboard.hwdb and wrote:

Code:

evdev:input:b0003v049Fp000E*
 KEYBOARD_KEY_c022a=key_x

049F being vendor ID and 000E product ID and I put key_x randomly to see if pressing the key would return something. After that I have run systemd-hwdb update ; udevadm trigger to update hwdb. Now I pressed every key on the top row and none of them outputs letter x. I was following this guide: https://deskthority.net/viewtopic.php?t=24076 and I am sure this method for remapping works because when I try to remap c00ea which is volume up key I do get letter x back.

I noticed is that the input-kbd returns the same output for events 13, 14 and 15 but here is the input-kbd of every event for this keyboard: https://pastebin.com/vsGtM2tc

I also thought that maybe those set of keys is dead, so I tried to record hid signals in wireshark and I do get signals back when I press those 7 keys.

Other than that I guess it could be that I have to press some key combination or to somehow enable those keys but nothing that I tried worked so far.

This keyboard is designed for windows 95/98 I think and there is a driver for it: https://www.driverguide.com/driver/d...riverid=121503 that I guess could be used to enable those keys but I didn't get it to work on neither windows system that I tried it on.

I appreciate if you have read this far and could give me some thoughts or you have some idea what more I can try?