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Date: Mon, 18 Feb 2013 12:35:15 +0200
From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: Doug Anderson <dianders@chromium.org>
Subject: Re: [PATCH] i2c: Remove unneeded xxx_set_drvdata(..., NULL) calls
Message-ID: <20130218103515.GJ20771@intel.com>
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 <1360970315-32116-1-git-send-email-dianders@chromium.org>
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Cc: Wolfram Sang <wsa@the-dreams.de>, Tony Lindgren <tony@atomide.com>,
 Linus Walleij <linus.walleij@linaro.org>,
 Thierry Reding <thierry.reding@avionic-design.de>,
 Sekhar Nori <nsekhar@ti.com>, linux-i2c@vger.kernel.org,
 Guan Xuetao <gxt@mprc.pku.edu.cn>, Kevin Hilman <khilman@ti.com>,
 Sonic Zhang <sonic.zhang@analog.com>, linux-arm-kernel@lists.infradead.org,
 Deepak Sikri <deepak.sikri@st.com>, Havard Skinnemoen <hskinnemoen@gmail.com>,
 Marek Vasut <marex@denx.de>, Pawel Moll <pawel.moll@arm.com>,
 Stephen Warren <swarren@wwwdotorg.org>, Sascha Hauer <s.hauer@pengutronix.de>,
 Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= <u.kleine-koenig@pengutronix.de>,
 Rob Herring <rob.herring@calxeda.com>, uclinux-dist-devel@blackfin.uclinux.org,
 Jean Delvare <khali@linux-fr.org>, Lars-Peter Clausen <lars@metafoo.de>,
 "Ben Dooks \(embedded platforms\)" <ben-linux@fluff.org>,
 Barry Song <baohua.song@csr.com>, linux-omap@vger.kernel.org,
 Oskar Schirmer <oskar@scara.com>, Fabio Estevam <fabio.estevam@freescale.com>,
 davinci-linux-open-source@linux.davincidsp.com,
 Shawn Guo <shawn.guo@linaro.org>, Jim Cromie <jim.cromie@gmail.com>,
 Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
 Tomoya MORINAGA <tomoya.rohm@gmail.com>, linux-kernel@vger.kernel.org,
 Kyungmin Park <kyungmin.park@samsung.com>,
 Viresh Kumar <viresh.linux@gmail.com>,
 Karol Lewandowski <k.lewandowsk@samsung.com>, Jiri Kosina <jkosina@suse.cz>,
 STEricsson <STEricsson_nomadik_linux@list.st.com>,
 Joe Perches <joe@perches.com>, Andrew Morton <akpm@linux-foundation.org>,
 Alessandro Rubini <rubini@unipv.it>, linuxppc-dev@lists.ozlabs.org,
 Alexander Stein <alexander.stein@systec-electronic.com>
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On Fri, Feb 15, 2013 at 03:18:35PM -0800, Doug Anderson wrote:
> There is simply no reason to be manually setting the private driver
> data to NULL in the remove/fail to probe cases.  This is just extra
> cruft code that can be removed.
> 
> A few notes:
> * Nothing relies on drvdata being set to NULL.
> * The __device_release_driver() function eventually calls
>   dev_set_drvdata(dev, NULL) anyway, so there's no need to do it
>   twice.
> * I verified that there were no cases where xxx_get_drvdata() was
>   being called in these drivers and checking for / relying on the NULL
>   return value.
> 
> This could be cleaned up kernel-wide but for now just take the baby
> step and remove from the i2c subsystem.
> 
> Reported-by: Wolfram Sang <wsa@the-dreams.de>
> Reported-by: Stephen Warren <swarren@wwwdotorg.org>
> Signed-off-by: Doug Anderson <dianders@chromium.org>
> ---
>  drivers/i2c/busses/i2c-au1550.c             | 1 -
>  drivers/i2c/busses/i2c-bfin-twi.c           | 2 --
>  drivers/i2c/busses/i2c-cpm.c                | 2 --
>  drivers/i2c/busses/i2c-davinci.c            | 2 --
>  drivers/i2c/busses/i2c-designware-pcidrv.c  | 2 --
>  drivers/i2c/busses/i2c-designware-platdrv.c | 2 --

For i2c-designware-pcidrv.c and i2c-designware-platdrv.c:

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>