Help with input_report_key not reporting key

Help with input_report_key not reporting key

[Jose Diez]

Hello linux-input,

Sorry to post about a similar question again, but I'm still stuck. So a 
bit of back story: I'm writing a custom HID driver which, among other 
things, will register several input devices.

I'm able to read HID reports from the device using the raw_event 
callback, and I'm able to communicate with the device, but I seem to 
have hit an obstacle I can't get over. I've tried to add a proper input 
device to the driver, and while it registers it properly and shows up in 
/dev/input/*, the events seem to not go through.

I found this simple kernel module, which indeed works properly and 
reports key events: http://sprunge.us/NLcD

I then adapted it to work with my kernel module, shown here: 
http://sprunge.us/egIi

It allocates the input device in fblng_probe(), sets the KEY_A bit in 
the keybit field, and registers it. Then, when a request comes to the 
device, in fblng_event(), I (try to) send a key with input_report_key. 
This doesn't seem to trigger a keypress.

I'm looking at the relevant /dev/input/eventX with `evtest`. I know I'm 
getting events through, because I can see it in `dmesg`. However, it 
doesn't actually go through to the input handler.

Any help, please?

Thanks a lot,
Jose

Re: Help with input_report_key not reporting key

[Jose Diez]

Hi,

Just figured out the solution to my own problem.

Turns out the linux input system will only report a key event if the 
value is different from the previous key report. In my case, I was only 
sending the value '1'.

Duh. I should have known that.

On 09/11/14 10:57, Jose Diez wrote:
> Hello linux-input,
>
> Sorry to post about a similar question again, but I'm still stuck. So a
> bit of back story: I'm writing a custom HID driver which, among other
> things, will register several input devices.
>
> I'm able to read HID reports from the device using the raw_event
> callback, and I'm able to communicate with the device, but I seem to
> have hit an obstacle I can't get over. I've tried to add a proper input
> device to the driver, and while it registers it properly and shows up in
> /dev/input/*, the events seem to not go through.
>
> I found this simple kernel module, which indeed works properly and
> reports key events: http://sprunge.us/NLcD
>
> I then adapted it to work with my kernel module, shown here:
> http://sprunge.us/egIi
>
> It allocates the input device in fblng_probe(), sets the KEY_A bit in
> the keybit field, and registers it. Then, when a request comes to the
> device, in fblng_event(), I (try to) send a key with input_report_key.
> This doesn't seem to trigger a keypress.
>
> I'm looking at the relevant /dev/input/eventX with `evtest`. I know I'm
> getting events through, because I can see it in `dmesg`. However, it
> doesn't actually go through to the input handler.
>
> Any help, please?
>
> Thanks a lot,
> Jose
> --
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