diff options
| author | Ladislav Michl | 2017-08-24 10:25:51 +0200 |
|---|---|---|
| committer | Jonathan Cameron | 2017-09-03 18:10:31 +0100 |
| commit | d1c11dc27e3282e787406290ead5926bb7bb4579 (patch) | |
| tree | 8d4f290d15b6a870d300a1da0d4402238225c497 | |
| parent | 4e57562b4846e42cd1c2e556f0ece18c1154e116 (diff) | |
iio: adc: ti-ads1015: write config register only on change
There is no point writing ADS1015_CFG_REG when configuration
didn't change. Avoid that.
Cc: Daniel Baluta <daniel.baluta@gmail.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
| -rw-r--r-- | drivers/iio/adc/ti-ads1015.c | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/drivers/iio/adc/ti-ads1015.c b/drivers/iio/adc/ti-ads1015.c index 731ec38276ea..7503ea56b781 100644 --- a/drivers/iio/adc/ti-ads1015.c +++ b/drivers/iio/adc/ti-ads1015.c @@ -332,7 +332,7 @@ static int ads1015_set_power_state(struct ads1015_data *data, bool on) static int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) { - int ret, pga, dr, conv_time; + int ret, pga, dr, dr_old, conv_time; unsigned int old, mask, cfg; if (chan < 0 || chan >= ADS1015_CHANNELS) @@ -358,15 +358,14 @@ int ads1015_get_adc_result(struct ads1015_data *data, int chan, int *val) } cfg = (old & ~mask) | (cfg & mask); - - ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg); - if (ret) - return ret; - - if (old != cfg || data->conv_invalid) { - int dr_old = (old & ADS1015_CFG_DR_MASK) >> - ADS1015_CFG_DR_SHIFT; - + if (old != cfg) { + ret = regmap_write(data->regmap, ADS1015_CFG_REG, cfg); + if (ret) + return ret; + data->conv_invalid = true; + } + if (data->conv_invalid) { + dr_old = (old & ADS1015_CFG_DR_MASK) >> ADS1015_CFG_DR_SHIFT; conv_time = DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr_old]); conv_time += DIV_ROUND_UP(USEC_PER_SEC, data->data_rate[dr]); usleep_range(conv_time, conv_time + 1); |