The ti-ads1015 driver has eight iio voltage channels and each iio channel can hold own scale information. The ADS1015 device only have a single config register which contains an input multiplexer selection, PGA and data rate settings. So the driver should load the correct settings when the input multiplexer selection is changed. However, regardless of which channlel is currently selected, changing any iio channel's scale information immediately overwrites the current PGA setting in the config register. It is harmless because the correct PGA settings are reloaded just before getting adc result anyway. But it is unnecessary register update and should be removed. Cc: Daniel Baluta <daniel.baluta@xxxxxxxxx> Cc: Jonathan Cameron <jic23@xxxxxxxxxx> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> --- drivers/iio/adc/ti-ads1015.c | 18 ++++-------------- 1 file changed, 4 insertions(+), 14 deletions(-) diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c index 9c501e5..e83cebc 100644 --- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -312,28 +312,18 @@ static int ads1015_set_scale(struct ads1015_data *data, struct iio_chan_spec const *chan, int scale, int uscale) { - int i, ret, rindex = -1; + int i; int fullscale = div_s64((scale * 1000000LL + uscale) << (chan->scan_type.realbits - 1), 1000000); for (i = 0; i < ARRAY_SIZE(ads1015_fullscale_range); i++) { if (ads1015_fullscale_range[i] == fullscale) { - rindex = i; - break; + data->channel_data[chan->address].pga = i; + return 0; } } - if (rindex < 0) - return -EINVAL; - - ret = regmap_update_bits(data->regmap, ADS1015_CFG_REG, - ADS1015_CFG_PGA_MASK, - rindex << ADS1015_CFG_PGA_SHIFT); - if (ret < 0) - return ret; - - data->channel_data[chan->address].pga = rindex; - return 0; + return -EINVAL; } static int ads1015_set_data_rate(struct ads1015_data *data, int chan, int rate) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html