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* [PATCH] staging: iio: ad7780: update voltage on read
@ 2018-10-25 13:32 Renato Lui Geh
  2018-10-25 13:38 ` Lars-Peter Clausen
  0 siblings, 1 reply; 5+ messages in thread
From: Renato Lui Geh @ 2018-10-25 13:32 UTC (permalink / raw)
  To: lars, Michael.Hennerich, jic23, knaack.h, pmeerw, gregkh,
	alexandru.Ardelean, stefan.popa, giuliano.belinassi
  Cc: linux-iio, devel, linux-kernel, kernel-usp

The ad7780 driver previously did not read the correct device output.
This patch fixes two issues.

- The driver read an outdated value set at initialization. It now
updates its voltage on read.
- Variable val subtracted an uninitialized value on
IIO_CHAN_INFO_OFFSET. This was fixed by assiging the correct value
instead.

Signed-off-by: Renato Lui Geh <renatogeh@gmail.com>
---
 drivers/staging/iio/adc/ad7780.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/iio/adc/ad7780.c b/drivers/staging/iio/adc/ad7780.c
index b67412db0318..06700fe554a2 100644
--- a/drivers/staging/iio/adc/ad7780.c
+++ b/drivers/staging/iio/adc/ad7780.c
@@ -87,16 +87,20 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
 			   long m)
 {
 	struct ad7780_state *st = iio_priv(indio_dev);
+	int voltage_uv = 0;
 
 	switch (m) {
 	case IIO_CHAN_INFO_RAW:
 		return ad_sigma_delta_single_conversion(indio_dev, chan, val);
 	case IIO_CHAN_INFO_SCALE:
+		voltage_uv = regulator_get_voltage(st->reg);
+		if (voltage_uv)
+			st->int_vref_mv = voltage_uv/1000;
 		*val = st->int_vref_mv * st->gain;
 		*val2 = chan->scan_type.realbits - 1;
 		return IIO_VAL_FRACTIONAL_LOG2;
 	case IIO_CHAN_INFO_OFFSET:
-		*val -= (1 << (chan->scan_type.realbits - 1));
+		*val = -(1 << (chan->scan_type.realbits - 1));
 		return IIO_VAL_INT;
 	}
 
-- 
2.19.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2018-10-25 16:01 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-10-25 13:32 [PATCH] staging: iio: ad7780: update voltage on read Renato Lui Geh
2018-10-25 13:38 ` Lars-Peter Clausen
2018-10-25 14:26   ` Renato Lui Geh
2018-10-25 14:55     ` Himanshu Jha
2018-10-25 16:01       ` Lars-Peter Clausen

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