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Subject: Re: [PATCH v14 00/11] mux controller abstraction and iio/i2c muxes
From: Philipp Zabel <p.zabel@pengutronix.de>
To: Peter Rosin <peda@axentia.se>
Cc: Jonathan Cameron <jic23@kernel.org>, linux-kernel@vger.kernel.org,
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Date: Mon, 24 Apr 2017 16:59:29 +0200
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On Mon, 2017-04-24 at 16:36 +0200, Peter Rosin wrote:
[...]
> > How about an atomic use_count on the mux_control, a bool shared that is
> > only set by the first consumer, and controls whether selecting locks?
> 
> That has the drawback that it is hard to restore the mux-control in a safe
> way so that exclusive consumers are allowed after the last shared consumer
> puts the mux away.

True.

> Agreed, it's a corner case, but I had this very similar
> patch going through the compiler when I got this mail. Does it work as well
> as what you suggested?

Yes, this patch works just as well.

regards
Philipp