Re: Inconsistent RC5 ir-keytable events

Marko Mäkelä
2022-01-03T12:21:11Z

Hi Sean,

Mon, Jan 03, 2022 at 11:07:43AM +0000, Sean Young wrote:
>I am not sure if the naked eye can observe a delay of 200ms rather than
>100ms.

I thought that I might be able to distinguish "fast blinking" (5Hz or
200ms) and "very fast blinking" (10Hz or 100ms), but I am not so sure
anymore.

>This is the timeout field on rcdev. I think it is set here:
>
>https://git.linuxtv.org/media_tree.git/tree/drivers/media/usb/dvb-usb-v2/rtl28xxu.c#n1810
>
>I think the interval is to set to value which is much to high; I think
>the 211 ms comes from this 200 value here. So, I think if you lower
>this to 100 then your problems might go away.

According to my old notes from this RCU, the repeat period was slightly
less than 110ms. In fact, the 212ms value from my output could be
2*106ms.

>I had forgotten that that for the delay between key down and key up,
>this also adds the repeat period for the protocol, see
>https://git.linuxtv.org/media_tree.git/tree/drivers/media/rc/rc-main.c#n857
>
>So actually that is 110ms + 9741us ≈ 119m, which is near enough the
>values seen above. I suspect the issue is the interval but please
>experiment.

If the correct threshold is 106ms and your suggestion of 100 does not
work, I will try a lower value, such as 94 or 95, to get 94+9.741 < 106.

I will get back to you once I have tested the change, hopefully during
this week.

Marko