Implement the .read_label callback to allow userspace to identify ADC channels via the "label" property in the device tree. The name field in pm8xxx_chan_info is renamed to label to better reflect its purpose. If no label is provided in the device tree, it defaults to the hardware datasheet name.
Tested-on: Sony Xperia SP (PM8921) Signed-off-by: Antony Kurniawan Soemardi <[email protected]> --- drivers/iio/adc/qcom-pm8xxx-xoadc.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/iio/adc/qcom-pm8xxx-xoadc.c b/drivers/iio/adc/qcom-pm8xxx-xoadc.c index 31f88cf7f7f18297132d152648b312c0fb60608e..206a379ea74113264d4e5e75a81f838204174700 100644 --- a/drivers/iio/adc/qcom-pm8xxx-xoadc.c +++ b/drivers/iio/adc/qcom-pm8xxx-xoadc.c @@ -369,7 +369,7 @@ static const struct xoadc_channel pm8921_xoadc_channels[] = { /** * struct pm8xxx_chan_info - ADC channel information - * @name: name of this channel + * @label: label of this channel from device tree (defaults to datasheet name if not specified) * @hwchan: pointer to hardware channel information (muxing & scaling settings) * @calibration: whether to use absolute or ratiometric calibration * @decimation: 0,1,2,3 @@ -377,7 +377,7 @@ static const struct xoadc_channel pm8921_xoadc_channels[] = { * calibration: 0, 1, 2, 4, 5. */ struct pm8xxx_chan_info { - const char *name; + const char *label; const struct xoadc_channel *hwchan; enum vadc_calibration calibration; u8 decimation:2; @@ -446,7 +446,7 @@ static int pm8xxx_read_channel_rsv(struct pm8xxx_xoadc *adc, u8 lsb, msb; dev_dbg(adc->dev, "read channel \"%s\", amux %d, prescale/mux: %d, rsv %d\n", - ch->name, ch->hwchan->amux_channel, ch->hwchan->pre_scale_mux, rsv); + ch->label, ch->hwchan->amux_channel, ch->hwchan->pre_scale_mux, rsv); mutex_lock(&adc->lock); @@ -725,8 +725,22 @@ static int pm8xxx_fwnode_xlate(struct iio_dev *indio_dev, return -EINVAL; } +static int pm8xxx_read_label(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, char *label) +{ + struct pm8xxx_xoadc *adc = iio_priv(indio_dev); + struct pm8xxx_chan_info *ch = pm8xxx_get_channel(adc, chan->address); + + if (!ch) { + dev_err(adc->dev, "no such channel %lu\n", chan->address); + return -EINVAL; + } + return sysfs_emit(label, "%s\n", ch->label); +} + static const struct iio_info pm8xxx_xoadc_info = { .fwnode_xlate = pm8xxx_fwnode_xlate, + .read_label = pm8xxx_read_label, .read_raw = pm8xxx_read_raw, }; @@ -770,7 +784,9 @@ static int pm8xxx_xoadc_parse_channel(struct device *dev, pre_scale_mux, amux_channel); return -EINVAL; } - ch->name = name; + ret = fwnode_property_read_string(fwnode, "label", &ch->label); + if (ret) + ch->label = hwchan->datasheet_name; ch->hwchan = hwchan; /* Everyone seems to use absolute calibration except in special cases */ ch->calibration = VADC_CALIB_ABSOLUTE; @@ -812,7 +828,7 @@ static int pm8xxx_xoadc_parse_channel(struct device *dev, dev_dbg(dev, "channel [PRESCALE/MUX: %02x AMUX: %02x] \"%s\" ref voltage: %d, decimation %d prescale %d/%d, scale function %d\n", - hwchan->pre_scale_mux, hwchan->amux_channel, ch->name, + hwchan->pre_scale_mux, hwchan->amux_channel, ch->label, ch->amux_ip_rsv, ch->decimation, hwchan->prescale.numerator, hwchan->prescale.denominator, hwchan->scale_fn_type); -- 2.34.1

