Messages in this thread | | | Subject | Re: [PATCH v7 00/10] Introduce the Counter subsystem | From | David Lechner <> | Date | Mon, 2 Jul 2018 13:13:40 -0500 |
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On 06/21/2018 04:06 PM, William Breathitt Gray wrote: > I decided to strip down these devices to arrive at the core essence of > what constitutes a "counter device" and therefore design a "generic > counter" abstraction to better represent these devices and prevent the > ambiguity we discovered with the existing IIO Counter interface. This > abstraction became the Generic Counter paradigm, which is explained in > detail within the Documentation/driver-api/generic-counter.rst file > introduced by this patchset.
I'm curious if you have given any thought to the time aspect of counters. I am interested in the rate at which the counters are counting (e.g. how many counts per second). I realize that you can calculate this in userspace or in the kernel using the system timer, but it is not very accurate since Linux is not a realtime OS. So, I would like to get the rate directly from the hardware. For example, the TI eQEP[1], like the one found in BeagleBones, has a couple ways of measuring time (see link for details).
[1]: http://www.ti.com/lit/ug/sprug05a/sprug05a.pdf
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