RE: [PATCH v2] iio: accel: mma8452: ignore the return value of reset operation

From: Bough Chen <haibo.chen@nxp.com>
To: Jonathan Cameron <jic23@kernel.org>, Hans de Goede <hdegoede@redhat.com>
Cc: "lars@metafoo.de" <lars@metafoo.de>,
	"linux-iio@vger.kernel.org" <linux-iio@vger.kernel.org>,
	dl-linux-imx <linux-imx@nxp.com>
Subject: RE: [PATCH v2] iio: accel: mma8452: ignore the return value of reset operation
Date: Thu, 16 Jun 2022 01:34:03 +0000	[thread overview]
Message-ID: <AM0PR04MB400175936806774093E463F590AC9@AM0PR04MB4001.eurprd04.prod.outlook.com> (raw)
In-Reply-To: <20220615221552.0d8afb3b@jic23-huawei>

> -----Original Message-----
> From: Jonathan Cameron <jic23@kernel.org>
> Sent: 2022年6月16日 5:16
> To: Hans de Goede <hdegoede@redhat.com>
> Cc: Bough Chen <haibo.chen@nxp.com>; lars@metafoo.de;
> linux-iio@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH v2] iio: accel: mma8452: ignore the return value of reset
> operation
> 
> On Wed, 15 Jun 2022 18:10:47 +0200
> Hans de Goede <hdegoede@redhat.com> wrote:
> 
> > Hi,
> >
> > On 6/15/22 13:31, haibo.chen@nxp.com wrote:
> > > From: Haibo Chen <haibo.chen@nxp.com>
> > >
> > > On fxls8471, after set the reset bit, the device will reset
> > > immediately, will not give ACK. So ignore the return value of this
> > > reset operation, let the following code logic to check whether the reset
> operation works.
> > >
> > > Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
> >
> > Thanks, patch looks good to me:
> >
> > Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> Looks very much like a fix to me, so fixes tag please.
> As it's otherwise good, just sending the tag in reply to this message will be fine.

Thanks for your quick review.

Fixes: ecabae713196 ("iio: mma8452: Initialise before activating")

Best Regards
Bough Chen
> 
> Thanks,
> 
> Jonathan
> 
> >
> > Regards,
> >
> > Hans
> >
> >
> >
> > > ---
> > >  drivers/iio/accel/mma8452.c | 10 +++++++---
> > >  1 file changed, 7 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/drivers/iio/accel/mma8452.c
> > > b/drivers/iio/accel/mma8452.c index e0f0c0abed28..c7d9ca96dbaa
> > > 100644
> > > --- a/drivers/iio/accel/mma8452.c
> > > +++ b/drivers/iio/accel/mma8452.c
> > > @@ -1511,10 +1511,14 @@ static int mma8452_reset(struct i2c_client
> *client)
> > >  	int i;
> > >  	int ret;
> > >
> > > -	ret = i2c_smbus_write_byte_data(client,	MMA8452_CTRL_REG2,
> > > +	/*
> > > +	 * Find on fxls8471, after config reset bit, it reset immediately,
> > > +	 * and will not give ACK, so here do not check the return value.
> > > +	 * The following code will read the reset register, and check whether
> > > +	 * this reset works.
> > > +	 */
> > > +	i2c_smbus_write_byte_data(client, MMA8452_CTRL_REG2,
> > >  					MMA8452_CTRL_REG2_RST);
> > > -	if (ret < 0)
> > > -		return ret;
> > >
> > >  	for (i = 0; i < 10; i++) {
> > >  		usleep_range(100, 200);
> >