iio: adc: ad7476: Use correct channel for bit info

The ad7476 supports ADCs which use separate GPIO for starting the
conversion. For such devices, the driver uses different channel
information if the GPIO is found. The bit information is still always
used from the original (non 'convstart') channels.

This has not been causing problems because the bit information for the
'convstart' -channel and the 'normal' -channel is identical. It,
however, will cause issues if an IC has different characteristics for an
'convstart' -channel and regular channel. Furthermore, this will cause
problems if a device always requires the convstart GPIO and thus only
defines the convstart channel.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/70619e39023bc497ef68cc1eff11943ab68cbdf8.1754901948.git.mazziesaccount@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Matti Vaittinen 2025-08-11 11:51:06 +03:00 committed by Jonathan Cameron
parent 1003d53993
commit 5e6847a02e

View File

@ -121,8 +121,8 @@ static int ad7476_read_raw(struct iio_dev *indio_dev,
if (ret < 0)
return ret;
*val = (ret >> st->chip_info->channel[0].scan_type.shift) &
GENMASK(st->chip_info->channel[0].scan_type.realbits - 1, 0);
*val = (ret >> chan->scan_type.shift) &
GENMASK(chan->scan_type.realbits - 1, 0);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = st->scale_mv;
@ -345,7 +345,7 @@ static int ad7476_probe(struct spi_device *spi)
/* Setup default message */
st->xfer.rx_buf = &st->data;
st->xfer.len = st->chip_info->channel[0].scan_type.storagebits / 8;
st->xfer.len = indio_dev->channels[0].scan_type.storagebits / 8;
spi_message_init(&st->msg);
spi_message_add_tail(&st->xfer, &st->msg);