[PATCH 4.9 10/32] iio: adc: ti-ads1015: enable conversion when CONFIG_PM is not set

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Akinobu Mita <akinobu.mita@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/iio/adc/ti-ads1015.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/drivers/iio/adc/ti-ads1015.c
+++ b/drivers/iio/adc/ti-ads1015.c
@@ -617,6 +617,13 @@ static int ads1015_probe(struct i2c_clie
 		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;