On Thu, Aug 22, 2019 at 03:43:39PM +0200, Michal Simek wrote: > On 20. 08. 19 17:39, Guenter Roeck wrote: > > On 8/12/19 6:29 AM, Michal Simek wrote: > >> There is no reason why power channel shouldn't be exported as is done for > >> voltage, current, temperature and humidity. > >> > >> Power channel is available on iio ina226 driver. > >> > >> Tested on Xilinx ZCU102 board. > >> > >> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx> > >> --- > >> > >> But I don't think values are properly converted. Voltage1 is fine but the > >> rest is IMHO wrong. But this patch should enable power channel to be > >> shown > >> which looks good. > >> > > > > No idea what is going on there. I don't really know what "scaled" units > > the iio subsystem reports. power is supposed to be reported to user space > > in micro-Watt. Is that what the scaled value from iio reports ? > > I have take a look at it again. > > root@zynqmp-debian:~/libiio/examples# sensors ina226_u76-* > ina226_u76-isa-0000 > Adapter: ISA adapter > in1: +0.01 V > in2: +0.85 V > power1: 1.16 mW > curr1: +1.60 A > > from iio_monitor > voltage0 0.007 V > voltage1 0.848 V > power2 1.150 W > current3 1.361 A > > from iio_info > IIO context has 18 devices: > iio:device0: ps_pmbus (buffer capable) > 9 channels found: > voltage0: (input, index: 0, format: le:U16/16>>0) > 3 channel-specific attributes found: > attr 0: integration_time value: 0.001100 > attr 1: raw value: 3152 > attr 2: scale value: 0.002500000 > voltage1: (input, index: 1, format: le:U16/16>>0) > 3 channel-specific attributes found: > attr 0: integration_time value: 0.001100 > attr 1: raw value: 678 > attr 2: scale value: 1.250000000 > power2: (input, index: 2, format: le:U16/16>>0) > 2 channel-specific attributes found: > attr 0: raw value: 106 > attr 1: scale value: 12.500000000 > current3: (input, index: 3, format: le:U16/16>>0) > 2 channel-specific attributes found: > attr 0: raw value: 3152 > attr 1: scale value: 0.500000000 > > > And if you look at power2 (in iio_info) then you see that calculation is > returning mili-Watts not micro-Watts. > > And looking at it back it is also said there. > > What: /sys/bus/iio/devices/iio:deviceX/in_powerY_raw > KernelVersion: 4.5 > Contact: linux-iio@xxxxxxxxxxxxxxx > Description: > Raw (unscaled no bias removal etc.) power measurement from > channel Y. The number must always be specified and > unique to allow association with event codes. Units after > application of scale and offset are milliwatts. > > That means for power channel value needs to be multiply by 1000. > > Are you OK with this solution? > Yes, looks good. Thanks, Guenter > diff --git a/drivers/hwmon/iio_hwmon.c b/drivers/hwmon/iio_hwmon.c > index aedb95fa24e3..7ea105bd195b 100644 > --- a/drivers/hwmon/iio_hwmon.c > +++ b/drivers/hwmon/iio_hwmon.c > @@ -44,12 +44,20 @@ static ssize_t iio_hwmon_read_val(struct device *dev, > int ret; > struct sensor_device_attribute *sattr = to_sensor_dev_attr(attr); > struct iio_hwmon_state *state = dev_get_drvdata(dev); > + struct iio_channel *chan = &state->channels[sattr->index]; > + enum iio_chan_type type; > > - ret = iio_read_channel_processed(&state->channels[sattr->index], > - &result); > + ret = iio_read_channel_processed(chan, &result); > if (ret < 0) > return ret; > > + ret = iio_get_channel_type(chan, &type); > + if (ret < 0) > + return ret; > + > + if (type == IIO_POWER) > + result *= 1000; > + > return sprintf(buf, "%d\n", result); > } > > > Thanks, > Michal
