| Message ID | 20210922153418.21033-8-olivier.moysan@foss.st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: stm32-adc: add internal channels support | expand |
On 9/22/21 5:34 PM, Olivier Moysan wrote: > Add st,min-sample-time-nsecs to channel generic binding. > Sample time can be defined par channel node. If a channel > is configured as differential, the same sample time applies > for both inputs. > Keep support of legacy st,min-sample-time-nsecs property > for backward compatibility. > > Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com> > --- > drivers/iio/adc/stm32-adc.c | 70 +++++++++++++++++++++---------------- > 1 file changed, 39 insertions(+), 31 deletions(-) > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c > index c427e439bf4a..cfd11ff0cf36 100644 > --- a/drivers/iio/adc/stm32-adc.c > +++ b/drivers/iio/adc/stm32-adc.c > @@ -1809,6 +1809,11 @@ static void stm32_adc_smpr_init(struct stm32_adc *adc, int channel, u32 smp_ns) > u32 period_ns, shift = smpr->shift, mask = smpr->mask; > unsigned int smp, r = smpr->reg; > > + /* > + * For vrefint channel, ensure that the sampling time cannot > + * be lower than the one specified in the datasheet > + */ > + Hi Olivier, I had a quick look at this series. It looks like some code is missing here, e.g. to check "ts_vrefint_ns". Thanks & BR, Fabrice > /* Determine sampling time (ADC clock cycles) */ > period_ns = NSEC_PER_SEC / adc->common->rate; > for (smp = 0; smp <= STM32_ADC_MAX_SMP; smp++) > @@ -1885,6 +1890,13 @@ static int stm32_adc_get_legacy_chan_count(struct iio_dev *indio_dev, struct stm > num_channels += ret; > } > > + /* Optional sample time is provided either for each, or all channels */ > + ret = of_property_count_u32_elems(node, "st,min-sample-time-nsecs"); > + if (ret > 1 && ret != num_channels) { > + dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs\n"); > + return -EINVAL; > + } > + > return num_channels; > } > > @@ -1900,6 +1912,7 @@ static int stm32_adc_legacy_chan_init(struct iio_dev *indio_dev, > int scan_index = 0, val, ret, i; > struct property *prop; > const __be32 *cur; > + u32 smp = 0; > > if (num_diff) { > ret = of_property_read_u32_array(node, "st,adc-diff-channels", > @@ -1942,6 +1955,19 @@ static int stm32_adc_legacy_chan_init(struct iio_dev *indio_dev, > scan_index++; > } > > + for (i = 0; i < scan_index; i++) { > + /* > + * Using of_property_read_u32_index(), smp value will only be > + * modified if valid u32 value can be decoded. This allows to > + * get either no value, 1 shared value for all indexes, or one > + * value per channel. > + */ > + of_property_read_u32_index(node, "st,min-sample-time-nsecs", i, &smp); > + > + /* Prepare sampling time settings */ > + stm32_adc_smpr_init(adc, channels[i].channel, smp); > + } > + > return scan_index; > } > > @@ -2034,6 +2060,19 @@ static int stm32_adc_generic_chan_init(struct iio_dev *indio_dev, > > stm32_adc_chan_init_one(indio_dev, &channels[scan_index], val, > vin[1], scan_index, differential); > + > + ret = of_property_read_u32(child, "st,min-sample-time-nsecs", &val); > + /* st,min-sample-time-nsecs is optional */ > + if (!ret) { > + stm32_adc_smpr_init(adc, channels[scan_index].channel, val); > + if (differential) > + stm32_adc_smpr_init(adc, vin[1], val); > + } else if (ret != -EINVAL) { > + dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs property %d\n", > + ret); > + goto err; > + } > + > scan_index++; > } > > @@ -2052,7 +2091,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) > const struct stm32_adc_info *adc_info = adc->cfg->adc_info; > struct iio_chan_spec *channels; > int scan_index = 0, num_channels = 0, ret, i; > - u32 smp = 0; > bool legacy = false; > > for (i = 0; i < STM32_ADC_INT_CH_NB; i++) > @@ -2080,13 +2118,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) > return -EINVAL; > } > > - /* Optional sample time is provided either for each, or all channels */ > - ret = of_property_count_u32_elems(node, "st,min-sample-time-nsecs"); > - if (ret > 1 && ret != num_channels) { > - dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs\n"); > - return -EINVAL; > - } > - > if (timestamping) > num_channels++; > > @@ -2103,29 +2134,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) > return ret; > scan_index = ret; > > - for (i = 0; i < scan_index; i++) { > - /* > - * Using of_property_read_u32_index(), smp value will only be > - * modified if valid u32 value can be decoded. This allows to > - * get either no value, 1 shared value for all indexes, or one > - * value per channel. > - */ > - of_property_read_u32_index(node, "st,min-sample-time-nsecs", > - i, &smp); > - > - /* > - * For vrefint channel, ensure that the sampling time cannot > - * be lower than the one specified in the datasheet > - */ > - if (channels[i].channel == adc->int_ch[STM32_ADC_INT_CH_VREFINT] && > - smp < adc->cfg->ts_vrefint_ns) { > - smp = adc->cfg->ts_vrefint_ns; > - } > - > - /* Prepare sampling time settings */ > - stm32_adc_smpr_init(adc, channels[i].channel, smp); > - } > - > if (timestamping) { > struct iio_chan_spec *timestamp = &channels[scan_index]; > >
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index c427e439bf4a..cfd11ff0cf36 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -1809,6 +1809,11 @@ static void stm32_adc_smpr_init(struct stm32_adc *adc, int channel, u32 smp_ns) u32 period_ns, shift = smpr->shift, mask = smpr->mask; unsigned int smp, r = smpr->reg; + /* + * For vrefint channel, ensure that the sampling time cannot + * be lower than the one specified in the datasheet + */ + /* Determine sampling time (ADC clock cycles) */ period_ns = NSEC_PER_SEC / adc->common->rate; for (smp = 0; smp <= STM32_ADC_MAX_SMP; smp++) @@ -1885,6 +1890,13 @@ static int stm32_adc_get_legacy_chan_count(struct iio_dev *indio_dev, struct stm num_channels += ret; } + /* Optional sample time is provided either for each, or all channels */ + ret = of_property_count_u32_elems(node, "st,min-sample-time-nsecs"); + if (ret > 1 && ret != num_channels) { + dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs\n"); + return -EINVAL; + } + return num_channels; } @@ -1900,6 +1912,7 @@ static int stm32_adc_legacy_chan_init(struct iio_dev *indio_dev, int scan_index = 0, val, ret, i; struct property *prop; const __be32 *cur; + u32 smp = 0; if (num_diff) { ret = of_property_read_u32_array(node, "st,adc-diff-channels", @@ -1942,6 +1955,19 @@ static int stm32_adc_legacy_chan_init(struct iio_dev *indio_dev, scan_index++; } + for (i = 0; i < scan_index; i++) { + /* + * Using of_property_read_u32_index(), smp value will only be + * modified if valid u32 value can be decoded. This allows to + * get either no value, 1 shared value for all indexes, or one + * value per channel. + */ + of_property_read_u32_index(node, "st,min-sample-time-nsecs", i, &smp); + + /* Prepare sampling time settings */ + stm32_adc_smpr_init(adc, channels[i].channel, smp); + } + return scan_index; } @@ -2034,6 +2060,19 @@ static int stm32_adc_generic_chan_init(struct iio_dev *indio_dev, stm32_adc_chan_init_one(indio_dev, &channels[scan_index], val, vin[1], scan_index, differential); + + ret = of_property_read_u32(child, "st,min-sample-time-nsecs", &val); + /* st,min-sample-time-nsecs is optional */ + if (!ret) { + stm32_adc_smpr_init(adc, channels[scan_index].channel, val); + if (differential) + stm32_adc_smpr_init(adc, vin[1], val); + } else if (ret != -EINVAL) { + dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs property %d\n", + ret); + goto err; + } + scan_index++; } @@ -2052,7 +2091,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) const struct stm32_adc_info *adc_info = adc->cfg->adc_info; struct iio_chan_spec *channels; int scan_index = 0, num_channels = 0, ret, i; - u32 smp = 0; bool legacy = false; for (i = 0; i < STM32_ADC_INT_CH_NB; i++) @@ -2080,13 +2118,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) return -EINVAL; } - /* Optional sample time is provided either for each, or all channels */ - ret = of_property_count_u32_elems(node, "st,min-sample-time-nsecs"); - if (ret > 1 && ret != num_channels) { - dev_err(&indio_dev->dev, "Invalid st,min-sample-time-nsecs\n"); - return -EINVAL; - } - if (timestamping) num_channels++; @@ -2103,29 +2134,6 @@ static int stm32_adc_chan_of_init(struct iio_dev *indio_dev, bool timestamping) return ret; scan_index = ret; - for (i = 0; i < scan_index; i++) { - /* - * Using of_property_read_u32_index(), smp value will only be - * modified if valid u32 value can be decoded. This allows to - * get either no value, 1 shared value for all indexes, or one - * value per channel. - */ - of_property_read_u32_index(node, "st,min-sample-time-nsecs", - i, &smp); - - /* - * For vrefint channel, ensure that the sampling time cannot - * be lower than the one specified in the datasheet - */ - if (channels[i].channel == adc->int_ch[STM32_ADC_INT_CH_VREFINT] && - smp < adc->cfg->ts_vrefint_ns) { - smp = adc->cfg->ts_vrefint_ns; - } - - /* Prepare sampling time settings */ - stm32_adc_smpr_init(adc, channels[i].channel, smp); - } - if (timestamping) { struct iio_chan_spec *timestamp = &channels[scan_index];
Add st,min-sample-time-nsecs to channel generic binding. Sample time can be defined par channel node. If a channel is configured as differential, the same sample time applies for both inputs. Keep support of legacy st,min-sample-time-nsecs property for backward compatibility. Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com> --- drivers/iio/adc/stm32-adc.c | 70 +++++++++++++++++++++---------------- 1 file changed, 39 insertions(+), 31 deletions(-)