RE: Intel timed i/o driver in HTE

"N, Pandith" <[email protected]> Tue, 29 Nov 2022 18:10:25 +0000
Newsgroups dev.linux.lists.timestamp,org.kernel.vger.linux-kernel
Message-ID <BYAPR11MB3240CE6547117D138B1A112DE1129@BYAPR11MB3240.namprd11.prod.outlook.com>
> -----Original Message-----
> From: Linus Walleij <[email protected]>
> Sent: Thursday, November 24, 2022 2:53 AM
> To: N, Pandith <[email protected]>
> Cc: Dipen Patel <[email protected]>; [email protected]; Hall,
> Christopher S <[email protected]>; Gross, Mark
> <[email protected]>; Sangannavar, Mallikarjunappa
> <[email protected]>; D, Lakshmi Sowjanya
> <[email protected]>; T R, Thejesh Reddy
> <[email protected]>; [email protected];
> [email protected]
> Subject: Re: Intel timed i/o driver in HTE
> 
> On Wed, Nov 23, 2022 at 3:38 PM N, Pandith <[email protected]> wrote:
> 
> > Since the current gpio framework is inadequate to periodic output modes.
> > I thought to disentangle from gpio and develop a new hte consumer.
> > Something like hte-libcdev.c
> 
> Maybe, if Dipen wants it.
> Or maybe it needs its own subsystem.
> Or maybe it should be with whatever is using these pulse trains.
> 
> Again: what is it used for? If we have no idea what it is supposed to be used
> for, we cannot place it right, even less test it.
> 
Intel  timed i/o is mainly intended for couple of functionalities.

1. Input event capture with timestamping 
2. Generate single shot or periodic pulse train

Use cases :
a. This has multiple uses like capturing trigger time and event count
b. Calculate periodicity in case of periodic signal on input pin 
c. Most importantly, precise time synchronization between devices/sub-systems 
Ex : Share precise time from a GPS receiver to the network or
       Synchronize processor clock with external signal.

> Yours,
> Linus Walleij

Regards,
Pandith