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Date: Sat, 3 Jun 2017 19:26:27 +0900
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: Peter Rosin <peda@lysator.liu.se>
Cc: linux-kernel@vger.kernel.org, Peter Rosin <peda@axentia.se>,
        Wolfram Sang <wsa@the-dreams.de>, Rob Herring <robh+dt@kernel.org>,
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        Colin Ian King <colin.king@canonical.com>,
        Paul Gortmaker <paul.gortmaker@windriver.com>,
        Philipp Zabel <p.zabel@pengutronix.de>, kernel@pengutronix.de
Subject: Re: [PATCH v15 00/13] mux controller abstraction and iio/i2c muxes
Message-ID: <20170603102627.GA24274@kroah.com>
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On Sun, May 14, 2017 at 09:51:03PM +0200, Peter Rosin wrote:
> From: Peter Rosin <peda@axentia.se>
> 
> Hi Greg,
> 
> Philipp found problems in v14 with using a mutex for locking that was
> the outcome of the review for v13, so I'm now using a semaphore instead
> of the rwsem that was in v13. That at least got rid of the scary call
> to downgrade_write. However, I'm still unsure about what you actually
> meant with your comment about lack of sparse markings [1]. I did add
> __must_check to the funcs that selects the mux, but I've got this
> feeling that this is not what you meant?

I thought there was a way to mark a function as requiring a lock be held
when it is being called.  Does sparse not support that anymore?

thanks,

greg k-h