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Date:   Tue, 29 Nov 2022 19:24:15 -0800
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Subject: Re: Intel timed i/o driver in HTE
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To:     Linus Walleij <linus.walleij@linaro.org>,
        "N, Pandith" <pandith.n@intel.com>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Hall, Christopher S" <christopher.s.hall@intel.com>,
        "Gross, Mark" <mark.gross@intel.com>,
        "Sangannavar, Mallikarjunappa" 
        <mallikarjunappa.sangannavar@intel.com>,
        "D, Lakshmi Sowjanya" <lakshmi.sowjanya.d@intel.com>,
        "T R, Thejesh Reddy" <thejesh.reddy.t.r@intel.com>,
        "andriy.shevchenko@linux.intel.com" 
        <andriy.shevchenko@linux.intel.com>,
        "timestamp@lists.linux.dev" <timestamp@lists.linux.dev>
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From:   Dipen Patel <dipenp@nvidia.com>
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On 11/23/22 1:22 PM, Linus Walleij wrote:
> On Wed, Nov 23, 2022 at 3:38 PM N, Pandith <pandith.n@intel.com> 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.
> 
Few things I want to know from Pandith as below:
1. Does timed io only meant for GPIO or other signals? if other signals, what type
of signals?
2. In the output mode case where for example, timed io IP outputs 1ms GPIO pulse,
does it also timestamp it for consumers to retrieve later?
3. Can you share rough idea you have in mind for the hte-libcdev?

> 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.
I think it can possibly act as time sync server as one of the use case. 
> 
> Yours,
> Linus Walleij