patch "iio: accel: mma8452: ignore the return value of reset operation" added to char-misc-linus

patch "iio: accel: mma8452: ignore the return value of reset operation" added to char-misc-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: accel: mma8452: ignore the return value of reset operation

to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From bf745142cc0a3e1723f9207fb0c073c88464b7b4 Mon Sep 17 00:00:00 2001
From: Haibo Chen <haibo.chen@nxp.com>
Date: Wed, 15 Jun 2022 19:31:58 +0800
Subject: iio: accel: mma8452: ignore the return value of reset operation

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>
---
 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 4156d216c640..f4f835274d75 100644
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -1510,10 +1510,14 @@ 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);
-- 
2.36.1