Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional

From	Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Newsgroups	linux.kernel
Subject	Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional
Date	2016-01-15 10:10 +0100
Message-ID	<qR8ym-3Yi-11@gated-at.bofh.it> (permalink)
References	<qR7sC-2Y8-7@gated-at.bofh.it> <qR7sC-2Y8-5@gated-at.bofh.it> <qR8f0-3AL-17@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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Hello Li,

On Fri, Jan 15, 2016 at 04:46:06PM +0800, Li Yang wrote:
> On Fri, Jan 15, 2016 at 3:53 PM, Uwe Kleine-König
> <u.kleine-koenig@pengutronix.de> wrote:
> >> -     i2c_imx_init_recovery_info(i2c_imx, pdev);
> >> +     if (IS_ERR_OR_NULL(i2c_imx->pinctrl))
> >
> > I'd prefer to set i2c_imx->pinctrl to NULL if it's not used and then use
> >
> >         if (!i2c_imx->pinctrl)
> >
> > here. (Or maybe make i2c_imx_init_recovery_info aware of this situation
> > to keep the caller simple?)
> 
> Setting not used pointer to NULL might be a good coding practice
> generally.  But in this case neither the driver nor gpio framework
> checks if the pinctrl is NULL before accessing it.  We still need the
> driver to make sure pinctrl is not used in this situation.  The
> benefit of the proposed change seems to be pretty limited.  :)

At least it gets rid of IS_ERR_OR_NULL which is used wrongly more often
than not.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

Thread

Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional Uwe Kleine-König   <u.kleine-koenig@pengutronix.de> - 2016-01-15 09:00 +0100
  Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional Li Yang <leoli@freescale.com> - 2016-01-15 09:50 +0100
    Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional Uwe Kleine-König   <u.kleine-koenig@pengutronix.de> - 2016-01-15 10:10 +0100
      Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional Li Yang <leoli@freescale.com> - 2016-01-18 09:30 +0100
        Re: [PATCH v3] i2c: imx: make bus recovery through pinctrl optional Uwe Kleine-König   <u.kleine-koenig@pengutronix.de> - 2016-01-18 09:40 +0100

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