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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, Miquel Raynal <miquel.raynal@bootlin.com>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 080/219] iio: adc: max1027: Reset the device at probe time
Date:   Sun, 29 Dec 2019 18:18:02 +0100
Message-Id: <20191229162517.783080437@linuxfoundation.org>
In-Reply-To: <20191229162508.458551679@linuxfoundation.org>
References: <20191229162508.458551679@linuxfoundation.org>
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From: Miquel Raynal <miquel.raynal@bootlin.com>

[ Upstream commit db033831b4f5589f9fcbadb837614a7c4eac0308 ]

All the registers are configured by the driver, let's reset the chip
at probe time, avoiding any conflict with a possible earlier
configuration.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/iio/adc/max1027.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
index 311c1a89c329..0939eb0384f1 100644
--- a/drivers/iio/adc/max1027.c
+++ b/drivers/iio/adc/max1027.c
@@ -460,6 +460,14 @@ static int max1027_probe(struct spi_device *spi)
 		goto fail_dev_register;
 	}
 
+	/* Internal reset */
+	st->reg = MAX1027_RST_REG;
+	ret = spi_write(st->spi, &st->reg, 1);
+	if (ret < 0) {
+		dev_err(&indio_dev->dev, "Failed to reset the ADC\n");
+		return ret;
+	}
+
 	/* Disable averaging */
 	st->reg = MAX1027_AVG_REG;
 	ret = spi_write(st->spi, &st->reg, 1);
-- 
2.20.1