From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Fri, 21 Jul 2017 00:24:19 +0900
Subject: [PATCH] iio: adc: ti-ads1015: enable conversion when CONFIG_PM is not
 set
References: bnc#1060662
Patch-mainline: 4.12.12
Git-commit: e8245c68350104b6022b6783719e843d69ea7c43

commit e8245c68350104b6022b6783719e843d69ea7c43 upstream.

The ADS1015 device have two operating modes, continuous conversion mode
and single-shot mode.  This driver assumes that the continuous conversion
mode is selected by runtime resume callback when the ADC result is
requested.

If CONFIG_PM is disabled, the device is always in the default single-shot
mode and no one begins a single conversion.  So the conversion register
doesn't contain valid ADC result.  Fix it by changing the continuous mode
in probe function.

Cc: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/iio/adc/ti-ads1015.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c
index eae89dfbed6c..0d0eb46b646e 100644
--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -623,6 +623,13 @@ static int ads1015_probe(struct i2c_client *client,
 		dev_err(&client->dev, "iio triggered buffer setup failed\n");
 		return ret;
 	}
+
+	ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG,
+				ADS1015_CFG_MOD_MASK,
+				ADS1015_CONTINUOUS << ADS1015_CFG_MOD_SHIFT);
+	if (ret)
+		return ret;
+
 	ret = pm_runtime_set_active(&client->dev);
 	if (ret)
 		goto err_buffer_cleanup;
-- 
2.14.2