From: "Daniel Glöckner" <daniel-gl@gmx.net>
To: Antti Palosaari <crope@iki.fi>
Cc: linux-media@vger.kernel.org, David Daney <david.daney@cavium.com>
Subject: Re: recursive locking problem
Date: Wed, 14 Sep 2011 08:19:22 +0200 [thread overview]
Message-ID: <20110914061922.GA1851@minime.bse> (raw)
In-Reply-To: <4E6FFD7E.2060500@iki.fi>
On Wed, Sep 14, 2011 at 04:03:58AM +0300, Antti Palosaari wrote:
> On 09/09/2011 02:46 PM, Daniel Glöckner wrote:
> >On Thu, Sep 08, 2011 at 07:34:32PM +0300, Antti Palosaari wrote:
> >>I am working with AF9015 I2C-adapter lock. I need lock I2C-bus since
> >>there is two tuners having same I2C address on same bus, demod I2C
> >>gate is used to select correct tuner.
> >
> >Would it be possible to use the i2c-mux framework to handle this?
> >Each tuner will then have its own i2c bus.
>
> Interesting idea, but it didn't worked. It deadlocks. I think it
> locks since I2C-mux is controlled by I2C "switch" in same I2C bus,
> not GPIO or some other HW.
Take a look at drivers/i2c/muxes/pca954x.c. You need to use
parent->algo->master_xfer/smbus_xfer directly as the lock that
protects you from having both gates open is the lock of the
root i2c bus.
Daniel
next prev parent reply other threads:[~2011-09-14 6:18 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-08 16:34 recursive locking problem Antti Palosaari
2011-09-09 7:51 ` Hans Petter Selasky
2011-09-09 10:45 ` David Waring
2011-09-13 20:59 ` Antti Palosaari
2011-09-13 21:34 ` Steve Kerrison
2011-09-13 21:58 ` Steven Toth
2011-09-13 22:10 ` Devin Heitmueller
2011-09-13 22:19 ` Steven Toth
2011-09-13 22:01 ` Devin Heitmueller
2011-09-09 11:46 ` Daniel Glöckner
2011-09-14 1:03 ` Antti Palosaari
2011-09-14 6:19 ` Daniel Glöckner [this message]
2011-09-14 10:45 ` Antti Palosaari
2011-09-14 12:22 ` Daniel Glöckner
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