RE: [PATCH v2] pinctrl: at91-pio4: implement .get_multiple and .set_multiple

From: David Laight
Date: Fri Sep 06 2019 - 05:05:43 EST


From: Alexandre Belloni
> Implement .get_multiple and .set_multiple to allow reading or setting
> multiple pins simultaneously. Pins in the same bank will all be switched at
> the same time, improving synchronization and performances.

Actually it won't 'improve synchronisation', instead it will lead to
random synchronisation errors and potential metastability if one
pin is used as a clock and another as data, or if the code is reading
a free-flowing counter.

It will improve performance though.

David

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