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From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Haibo Chen <haibo.chen@nxp.com>,
        Hans de Goede <hdegoede@redhat.com>, Stable@vger.kernel.org,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>
Subject: [PATCH 4.19 26/49] iio: accel: mma8452: ignore the return value of reset operation
Date:   Thu, 30 Jun 2022 15:46:39 +0200
Message-Id: <20220630133234.668762216@linuxfoundation.org>
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From: Haibo Chen <haibo.chen@nxp.com>

commit bf745142cc0a3e1723f9207fb0c073c88464b7b4 upstream.

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>
Fixes: ecabae713196 ("iio: mma8452: Initialise before activating")
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/1655292718-14287-1-git-send-email-haibo.chen@nxp.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/iio/accel/mma8452.c |   10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -1486,10 +1486,14 @@ static int mma8452_reset(struct i2c_clie
 	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);