To: linux-kernel@vger.kernel.org
From: "Enrico Weigelt, metux IT consult" <enrico.weigelt@gr13.net>
Subject: Best practise for a polling device driver ?
Message-ID: <ac00e8ed-b11a-faac-d8f9-1e7616e40070@gr13.net>
Date: Thu, 29 Jun 2017 12:04:14 +0000
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Hi folks,

I'm currently writing a driver for an (pseudo-)serial device
(actually, a bunch of HW fifo's, which look like serial controllers
to the host), which only supports polling, no interrupts.

So far, I'm just using a kthread in a loop, but that would have to
run w/ high priority sleep very short (needs to transfer several
MB/s on a am33xx), so probably not a good idea.

Another option could be using timers for just looking at the status
registers and issue sw interrupts, which are then handled just like
the w/ the usual interrupt-driven serial ports (IOW: mimic an
interrupt controller).

What do you folks thinkt about that ?


thx.
--mtx