[PATCH v15 07/13] docs: counter: Document character device interface

William Breathitt Gray vilhelm.gray at gmail.com
Sat Aug 21 03:52:27 PDT 2021


On Sun, Aug 15, 2021 at 05:51:02PM +0100, Jonathan Cameron wrote:
> On Mon,  9 Aug 2021 21:37:32 +0900
> William Breathitt Gray <vilhelm.gray at gmail.com> wrote:
> 
> > This patch adds high-level documentation about the Counter subsystem
> > character device interface.
> > 
> > Signed-off-by: William Breathitt Gray <vilhelm.gray at gmail.com>
> 
> Hi William,
> 
> Trivial probable typo inline.
> 
> I'm struggling somewhat with these interfaces because I simply don't know
> enough about how people use counters to know whether they provide everything
> people will want. They feel similar to the event handling type functions you
> can set up in motor drives, so they may well make sense, but ideally
> we need review from someone (other than yourself!) who actually uses this
> stuff on a regular basis.
> 
> If we don't get any additional review I guess we go ahead anyway
> next cycle.
> 
> Jonathan
> 
> > ---
> 
> > +
> > +Counter events can be configured by users to report various Counter
> > +data of interest. This can be conceptualized as a list of Counter
> > +component read calls to perform. For example:
> > +
> > +        +-------------------------------------------------+
> > +        | COUNTER_EVENT_OVERFLOW | COUNTER_EVENT_INDEX    |
> > +        +========================+========================+
> > +        | Channel 0              | Channel 0              |
> > +        +------------------------+------------------------+
> > +        | * Count 0              | * Signal 0             |
> > +        | * Count 1              | * Signal 0 Extension 0 |
> > +        | * Signal 3             | * Extension 4          |
> > +        | * Count 4 Extension 2  +------------------------+
> > +        | * Signal 5 Extension 0 | Channel 1              |
> > +        |                        +------------------------+
> > +        |                        | * Signal 4             |
> > +        |                        | * Signal 4 Extension 0 |
> > +        |                        | * Count 7              |
> > +        +------------------------+------------------------+
> > +
> > +When ``counter_push_event(counter, COUNTER_EVENT_INDEX, 1)`` is called
> > +for example, it will go down the list for the ``COUNTER_EVENT_INDEX``
> > +event channel 1 and execute the read callbacks for Signal 4, Signal 4
> > +Extension 0, and Count 4 -- the data returned for each is pushed to a
> 
> Count 7?

Looks like my finger slipped on my numpad and hit 4 when I intended 7.
I'll fix this for v16, thanks.

William Breathitt Gray
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