How to enumerate a list of all possible inputs on a device?

I originally asked [this question](https://android.stackexchange.com/questions/252453/how-to-enumerate-all-possible-adb-shell-input-keyevent-codes-for-a-device) , but it never received any responses save for a few comments. I'd like to broaden my approach, and ask if there is anyway to enumerate a list of **all** possible inputs that an Android device can receive? I've come across [this](https://stackoverflow.com/questions/6990978/how-can-i-know-which-of-the-dev-input-eventx-x-0-7-have-the-linux-input-stre) post as well just earlier (currently still attempting to digest the information). Here is a list of devices, output from cat /proc/bus/input/devices:

I: Bus=0019 Vendor=0001 Product=0001 Version=0100
N: Name="gpio-keys"
P: Phys=gpio-keys/input0
S: Sysfs=/devices/platform/gpio-keys.0/input/input0
U: Uniq=
H: Handlers=kbd event0
B: PROP=0
B: EV=3
B: KEY=8000 0 0 0 0

I: Bus=001c Vendor=0000 Product=0000 Version=0000
N: Name="a3g4250d"
P: Phys=
S: Sysfs=/devices/platform/spi_tegra.4/spi4.2/input/input2
U: Uniq=
H: Handlers=event2
B: PROP=0
B: EV=9
B: ABS=7

I: Bus=001c Vendor=0000 Product=0000 Version=0000
N: Name="a3g4250d_temp"
P: Phys=
S: Sysfs=/devices/platform/spi_tegra.4/spi4.2/input/input3
U: Uniq=
H: Handlers=event3
B: PROP=0
B: EV=9
B: ABS=100 0

I: Bus=0018 Vendor=0001 Product=0002 Version=0000
N: Name="uinput4strgsw"
P: Phys=
S: Sysfs=/devices/virtual/input/input4
U: Uniq=
H: Handlers=kbd event4
B: PROP=0
B: EV=3
B: KEY=1fff0000 0 0 0 0 0 0 7 f8000000 0

I: Bus=0018 Vendor=2222 Product=2222 Version=0000
N: Name="uinput4lvds"
P: Phys=
S: Sysfs=/devices/virtual/input/input6
U: Uniq=
H: Handlers=kbd event5
B: PROP=0
B: EV=b
B: KEY=1000 40000800 0 0 0 0
B: ABS=600000 0

I: Bus=0003 Vendor=0e8f Product=2519 Version=0110
N: Name="HID 0e8f:2519"
P: Phys=usb-tegra-ehci.1-1/input1
S: Sysfs=/devices/platform/tegra-ehci.1/usb1/1-1/1-1:1.1/input/input9
U: Uniq=
H: Handlers=kbd mouse0 event1
B: PROP=0
B: EV=1f
B: KEY=4837fff 72ff32d bf544446 0 0 1f0001 20f90 8b17c000 677bfa d941dfed 9ed680 4400 0 10000002
B: REL=143
B: ABS=1 0
B: MSC=10