linux-kernel - Re: [PATCH 1/4] spi: Add option to wake a device by toggling CS

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Message-ID: <20160701080230.GB6247@sirena.org.uk>
Date:	Fri, 1 Jul 2016 09:02:30 +0100
From:	Mark Brown <broonie@...nel.org>
To:	apronin@...omium.org
Cc:	linux-kernel@...r.kernel.org, linux-spi@...r.kernel.org
Subject: Re: [PATCH 1/4] spi: Add option to wake a device by toggling CS

On Wed, Jun 29, 2016 at 08:54:24PM -0700, apronin@...omium.org wrote:
> From: Andrey Pronin <apronin@...omium.org>
> 
> Some SPI devices may go to sleep after a period of inactivity
> on SPI. For such devices, if enough time has passed since the
> last SPI transaction, toggle CS and wait for the device to
> start before communicating with it.

This seems incredibly specialist, I can imagine someone might implement
something like this but it really feels like something I'd expect the
driver for the device to be doing rather than the core.  Is it really a
bounce that's needed and not something like putting a small delay after
asserting chip select?

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