[PATCH] iio: adc: ti-ads7950: Ensure CS is deasserted after reading channels

["Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>]

The ADS7950 requires that CS is deasserted after each SPI word. Before
commit e2540da86ef8 ("iio: adc: ti-ads7950: use SPI_CS_WORD to reduce
CPU usage") the driver used a message with one spi transfer per channel
where each but the last one had .cs_change set to enforce a CS toggle.
This was wrongly translated into a message with a single transfer and
.cs_change set which results in a CS toggle after each word but the
last which corrupts the first adc conversion of all readouts after the
first readout.

Fixes: e2540da86ef8 ("iio: adc: ti-ads7950: use SPI_CS_WORD to reduce CPU usage")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
---
 drivers/iio/adc/ti-ads7950.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/iio/adc/ti-ads7950.c b/drivers/iio/adc/ti-ads7950.c
index 2383eacada87..a2b83f0bd526 100644
--- a/drivers/iio/adc/ti-ads7950.c
+++ b/drivers/iio/adc/ti-ads7950.c
@@ -568,7 +568,6 @@ static int ti_ads7950_probe(struct spi_device *spi)
 	st->ring_xfer.tx_buf = &st->tx_buf[0];
 	st->ring_xfer.rx_buf = &st->rx_buf[0];
 	/* len will be set later */
-	st->ring_xfer.cs_change = true;
 
 	spi_message_add_tail(&st->ring_xfer, &st->ring_msg);
 
-- 
2.30.2