| Message ID | 20200416205428.437503-3-alexandre.belloni@bootlin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: ti-ads8344: driver improvements | expand |
On Thu, 16 Apr 2020 22:54:28 +0200 Alexandre Belloni <alexandre.belloni@bootlin.com> wrote: > Set the clock mode only once, at probe time and then keep the ADC powered > down between conversions. > > Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Looks fine to me. I'd like to be lazy and not take this until the fix is in my upstream (even though I suspect the merge would be fine). Give me a poke if I seem to have forgotten this after that is true! Thanks, Jonathan > --- > drivers/iio/adc/ti-ads8344.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c > index abe4b56c847c..40e7a9eee189 100644 > --- a/drivers/iio/adc/ti-ads8344.c > +++ b/drivers/iio/adc/ti-ads8344.c > @@ -72,7 +72,7 @@ static const struct iio_chan_spec ads8344_channels[] = { > }; > > static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > - bool differential) > + bool differential, u8 clock) > { > struct spi_device *spi = adc->spi; > int ret; > @@ -81,7 +81,7 @@ static int ads8344_adc_conversion(struct ads8344 *adc, int channel, > if (!differential) > adc->tx_buf |= ADS8344_SINGLE_END; > adc->tx_buf |= ADS8344_CHANNEL(channel); > - adc->tx_buf |= ADS8344_CLOCK_INTERNAL; > + adc->tx_buf |= clock; > > ret = spi_write(spi, &adc->tx_buf, 1); > if (ret) > @@ -106,7 +106,7 @@ static int ads8344_read_raw(struct iio_dev *iio, > case IIO_CHAN_INFO_RAW: > mutex_lock(&adc->lock); > *value = ads8344_adc_conversion(adc, channel->scan_index, > - channel->differential); > + channel->differential, 0); > mutex_unlock(&adc->lock); > if (*value < 0) > return *value; > @@ -161,6 +161,11 @@ static int ads8344_probe(struct spi_device *spi) > if (ret) > return ret; > > + /* Do a dummy read and set external clock mode */ > + ret = ads8344_adc_conversion(adc, 0, 0, ADS8344_CLOCK_INTERNAL); > + if (ret < 0) > + return ret; > + > spi_set_drvdata(spi, indio_dev); > > ret = iio_device_register(indio_dev);
Hi, On 18/04/2020 16:13:22+0100, Jonathan Cameron wrote: > On Thu, 16 Apr 2020 22:54:28 +0200 > Alexandre Belloni <alexandre.belloni@bootlin.com> wrote: > > > Set the clock mode only once, at probe time and then keep the ADC powered > > down between conversions. > > > > Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> > Looks fine to me. I'd like to be lazy and not take this until the fix is > in my upstream (even though I suspect the merge would be fine). > > Give me a poke if I seem to have forgotten this after that is true! > It now landed in your upstream but I guess you want to take Gregory's patch as a fix first. To be honest I don't think any of the fixes are urgent as it seems we are the only users of the particular ADC.
diff --git a/drivers/iio/adc/ti-ads8344.c b/drivers/iio/adc/ti-ads8344.c index abe4b56c847c..40e7a9eee189 100644 --- a/drivers/iio/adc/ti-ads8344.c +++ b/drivers/iio/adc/ti-ads8344.c @@ -72,7 +72,7 @@ static const struct iio_chan_spec ads8344_channels[] = { }; static int ads8344_adc_conversion(struct ads8344 *adc, int channel, - bool differential) + bool differential, u8 clock) { struct spi_device *spi = adc->spi; int ret; @@ -81,7 +81,7 @@ static int ads8344_adc_conversion(struct ads8344 *adc, int channel, if (!differential) adc->tx_buf |= ADS8344_SINGLE_END; adc->tx_buf |= ADS8344_CHANNEL(channel); - adc->tx_buf |= ADS8344_CLOCK_INTERNAL; + adc->tx_buf |= clock; ret = spi_write(spi, &adc->tx_buf, 1); if (ret) @@ -106,7 +106,7 @@ static int ads8344_read_raw(struct iio_dev *iio, case IIO_CHAN_INFO_RAW: mutex_lock(&adc->lock); *value = ads8344_adc_conversion(adc, channel->scan_index, - channel->differential); + channel->differential, 0); mutex_unlock(&adc->lock); if (*value < 0) return *value; @@ -161,6 +161,11 @@ static int ads8344_probe(struct spi_device *spi) if (ret) return ret; + /* Do a dummy read and set external clock mode */ + ret = ads8344_adc_conversion(adc, 0, 0, ADS8344_CLOCK_INTERNAL); + if (ret < 0) + return ret; + spi_set_drvdata(spi, indio_dev); ret = iio_device_register(indio_dev);
Set the clock mode only once, at probe time and then keep the ADC powered down between conversions. Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> --- drivers/iio/adc/ti-ads8344.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)