lkml.org 
[lkml]   [2014]   [Dec]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH 4/8] iio: core: Introduce IO_CHAN_INFO_CALIBWEIGHT
Date


> -----Original Message-----
> From: Jonathan Cameron [mailto:jic23@kernel.org]
> Sent: 26 December, 2014 15:31
> To: Tirdea, Irina; linux-iio@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org; Dogaru, Vlad; Baluta, Daniel; Hartmut Knaack; Lars-Peter Clausen; Peter Meerwald
> Subject: Re: [PATCH 4/8] iio: core: Introduce IO_CHAN_INFO_CALIBWEIGHT
>
> On 19/12/14 22:57, Irina Tirdea wrote:
> > Some devices need the weight of the user to compute other
> > parameters. One of this devices is Freescale's MMA9553L
> > (http://www.freescale.com/files/sensors/doc/ref_manual/MMA9553LSWRM.pdf)
> > that needs the weight of the user to compute the number of calories burnt.
> >
> > Signed-off-by: Irina Tirdea <irina.tirdea@intel.com>
> > ---
> > Documentation/ABI/testing/sysfs-bus-iio | 7 +++++++
> > drivers/iio/industrialio-core.c | 1 +
> > include/linux/iio/iio.h | 1 +
> > 3 files changed, 9 insertions(+)
> >
> > diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> > index 07acef7..e480175 100644
> > --- a/Documentation/ABI/testing/sysfs-bus-iio
> > +++ b/Documentation/ABI/testing/sysfs-bus-iio
> > @@ -351,6 +351,13 @@ Description:
> > to compute the stride length, distance, speed and activity
> > type.
> >
> > +What: /sys/bus/iio/devices/iio:deviceX/in_steps_calibweight
> > +KernelVersion: 3.19
> > +Contact: linux-iio@vger.kernel.org
> > +Description:
> > + Weight of the user (in kg). It is needed by some pedometers
> > + to compute the calories burnt by the user.
> How about grams? Nice to keep to SI units going forward (I appreciate we
> have broken that for what seemed like good reasons at the time) in one
> or two places, but it makes it much harder to define consistent interfaces in the
> long run.

According to SI [1] kg is the base unit for mass, so this was the obvious first choice.
I have nothing against using grams, but it is not clear to me why using grams would make it easier to define consistent interfaces in the long run.
I am probably missing something, so could you please clarify this?

Thanks,
Irina

[1] http://www.bipm.org/en/measurement-units/

> J
> > +
> > What: /sys/bus/iio/devices/iio:deviceX/in_accel_scale_available
> > What: /sys/.../iio:deviceX/in_voltageX_scale_available
> > What: /sys/.../iio:deviceX/in_voltage-voltage_scale_available
> > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> > index 5e50aca..4c435c8 100644
> > --- a/drivers/iio/industrialio-core.c
> > +++ b/drivers/iio/industrialio-core.c
> > @@ -124,6 +124,7 @@ static const char * const iio_chan_info_postfix[] = {
> > [IIO_CHAN_INFO_INT_TIME] = "integration_time",
> > [IIO_CHAN_INFO_ENABLE] = "en",
> > [IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",
> > + [IIO_CHAN_INFO_CALIBWEIGHT] = "calibweight",
> > };
> >
> > /**
> > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> > index 878d861..752a929 100644
> > --- a/include/linux/iio/iio.h
> > +++ b/include/linux/iio/iio.h
> > @@ -40,6 +40,7 @@ enum iio_chan_info_enum {
> > IIO_CHAN_INFO_INT_TIME,
> > IIO_CHAN_INFO_ENABLE,
> > IIO_CHAN_INFO_CALIBHEIGHT,
> > + IIO_CHAN_INFO_CALIBWEIGHT,
> > };
> >
> > enum iio_shared_by {
> >



\
 
 \ /
  Last update: 2014-12-29 16:21    [W:0.056 / U:0.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site