From: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
commit dd7de4c0023e7564cabe39d64b2822a522890792 upstream.
The first received byte is the MSB, followed by the LSB so the value needs
to be byte swapped.
Also, the ADC actually has a delay of one clock on the SPI bus. Read three
bytes to get the last bit.
Fixes: 8dd2d7c0fed7 ("iio: adc: Add driver for the TI ADS8344 A/DC chips")
Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/iio/adc/ti-ads8344.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/iio/adc/ti-ads8344.c
+++ b/drivers/iio/adc/ti-ads8344.c
@@ -29,7 +29,7 @@ struct ads8344 {
struct mutex lock;
u8 tx_buf ____cacheline_aligned;
- u16 rx_buf;
+ u8 rx_buf[3];
};
#define ADS8344_VOLTAGE_CHANNEL(chan, si) \
@@ -89,11 +89,11 @@ static int ads8344_adc_conversion(struct
udelay(9);
- ret = spi_read(spi, &adc->rx_buf, 2);
+ ret = spi_read(spi, adc->rx_buf, sizeof(adc->rx_buf));
if (ret)
return ret;
- return adc->rx_buf;
+ return adc->rx_buf[0] << 9 | adc->rx_buf[1] << 1 | adc->rx_buf[2] >> 7;
}
static int ads8344_read_raw(struct iio_dev *iio,
