From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Sun, 25 Nov 2018 16:35:34 +0100 From: Tomasz Duszynski To: Jonathan Cameron Cc: Matt Ranostay , Tomasz Duszynski , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [PATCH 1/3] iio: add IIO_MASSCONCENTRATION channel type Message-ID: <20181125153533.GB5053@arch> References: <20181124221415.10081-1-tduszyns@gmail.com> <20181124221415.10081-2-tduszyns@gmail.com> <20181125140316.59d9872b@archlinux> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <20181125140316.59d9872b@archlinux> List-ID: On Sun, Nov 25, 2018 at 02:03:16PM +0000, Jonathan Cameron wrote: > On Sun, 25 Nov 2018 05:51:32 -0800 > Matt Ranostay wrote: > > > On Sat, Nov 24, 2018 at 2:14 PM Tomasz Duszynski wrote: > > > > > > Measuring particulate matter in ug / m3 (micro-grams per cubic meter) > > > is de facto standard. Existing air quality sensors usually follow > > > this convention and are capable of returning measurements using > > > this unit. > > > > > > IIO currently does not offer suitable channel type for this > > > type of measurements hence this patch adds this. > > > > > > In addition, two modifiers are introduced used for distinguishing > > > between coarse (PM10) and fine particles (PM2p5) measurements, i.e > > > IIO_MOD_PM10 and IIO_MOD_PM2p5. > > > > > > Signed-off-by: Tomasz Duszynski > > > --- > > > Documentation/ABI/testing/sysfs-bus-iio | 11 ++++++++++- > > > drivers/iio/industrialio-core.c | 3 +++ > > > include/uapi/linux/iio/types.h | 3 +++ > > > tools/iio/iio_event_monitor.c | 6 ++++++ > > > 4 files changed, 22 insertions(+), 1 deletion(-) > > > > > > diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio > > > index 8127a08e366d..ce0ed140660d 100644 > > > --- a/Documentation/ABI/testing/sysfs-bus-iio > > > +++ b/Documentation/ABI/testing/sysfs-bus-iio > > > @@ -1684,4 +1684,13 @@ KernelVersion: 4.18 > > > Contact: linux-iio@vger.kernel.org > > > Description: > > > Raw (unscaled) phase difference reading from channel Y > > > - that can be processed to radians. > > > \ No newline at end of file > > > + that can be processed to radians. > > > + > > > +What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm2p5_input > > > +What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm2p5_input > > > +What: /sys/bus/iio/devices/iio:deviceX/in_massconcentration_pm10_input > > > +What: /sys/bus/iio/devices/iio:deviceX/in_massconcentrationY_pm10_input > > > +KernelVersion: 4.21 > > > +Contact: linux-iio@vger.kernel.org > > > +Description: > > > + Mass concentration reading of particulate matter in ug / m3. > > > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c > > > index a062cfddc5af..2a9ef600c1fb 100644 > > > --- a/drivers/iio/industrialio-core.c > > > +++ b/drivers/iio/industrialio-core.c > > > @@ -87,6 +87,7 @@ static const char * const iio_chan_type_name_spec[] = { > > > [IIO_GRAVITY] = "gravity", > > > [IIO_POSITIONRELATIVE] = "positionrelative", > > > [IIO_PHASE] = "phase", > > > + [IIO_MASSCONCENTRATION] = "massconcentration", > > > }; > > > > > > static const char * const iio_modifier_names[] = { > > > @@ -127,6 +128,8 @@ static const char * const iio_modifier_names[] = { > > > [IIO_MOD_Q] = "q", > > > [IIO_MOD_CO2] = "co2", > > > [IIO_MOD_VOC] = "voc", > > > + [IIO_MOD_PM2p5] = "pm2p5", > > > + [IIO_MOD_PM10] = "pm10", > > > }; > > > > > > /* relies on pairs of these shared then separate */ > > > diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h > > > index 92baabc103ac..465044b42af5 100644 > > > --- a/include/uapi/linux/iio/types.h > > > +++ b/include/uapi/linux/iio/types.h > > > @@ -46,6 +46,7 @@ enum iio_chan_type { > > > IIO_GRAVITY, > > > IIO_POSITIONRELATIVE, > > > IIO_PHASE, > > > + IIO_MASSCONCENTRATION, > > > > So I'm guessing IIO_CONCENTRATION can't be scaled to the micro-grams > > per cubic meter? > > Currently concentration is defined as a percentage reading of a substance > (which does make me wonder if it is meant to be percentage of the volume or > percentage of the mass?) Either way, if can't convert to a density measurement > as it's a unit free ratio (I think). > And this is the main reason behind introducing a new channel type. > > > > > }; > > > > > > enum iio_modifier { > > > @@ -87,6 +88,8 @@ enum iio_modifier { > > > IIO_MOD_VOC, > > > IIO_MOD_LIGHT_UV, > > > IIO_MOD_LIGHT_DUV, > > > + IIO_MOD_PM2p5, > > > > I know this is unit of measure but the lowercase p in IIO_MOD_PM2p5 is > > a bit non-standard for iio defines/enum. > It is a bit odd and will get us scripted reports so maybe best to > just go upper case and not worry about it. > Initially I came up with IIO_MOD_PM2_5 but eventually replaced underscore with 'p' meaning 'decimal point'. Anyway, I am okay with the suggested change. > Jonathan > > > > - Matt > > > > > + IIO_MOD_PM10, > > > }; > > > > > > enum iio_event_type { > > > diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c > > > index ac2de6b7e89f..f0fcfeddba2b 100644 > > > --- a/tools/iio/iio_event_monitor.c > > > +++ b/tools/iio/iio_event_monitor.c > > > @@ -60,6 +60,7 @@ static const char * const iio_chan_type_name_spec[] = { > > > [IIO_GRAVITY] = "gravity", > > > [IIO_POSITIONRELATIVE] = "positionrelative", > > > [IIO_PHASE] = "phase", > > > + [IIO_MASSCONCENTRATION] = "massconcentration", > > > }; > > > > > > static const char * const iio_ev_type_text[] = { > > > @@ -115,6 +116,8 @@ static const char * const iio_modifier_names[] = { > > > [IIO_MOD_Q] = "q", > > > [IIO_MOD_CO2] = "co2", > > > [IIO_MOD_VOC] = "voc", > > > + [IIO_MOD_PM2p5] = "pm2p5", > > > + [IIO_MOD_PM10] = "pm10", > > > }; > > > > > > static bool event_is_known(struct iio_event_data *event) > > > @@ -156,6 +159,7 @@ static bool event_is_known(struct iio_event_data *event) > > > case IIO_GRAVITY: > > > case IIO_POSITIONRELATIVE: > > > case IIO_PHASE: > > > + case IIO_MASSCONCENTRATION: > > > break; > > > default: > > > return false; > > > @@ -200,6 +204,8 @@ static bool event_is_known(struct iio_event_data *event) > > > case IIO_MOD_Q: > > > case IIO_MOD_CO2: > > > case IIO_MOD_VOC: > > > + case IIO_MOD_PM2p5: > > > + case IIO_MOD_PM10: > > > break; > > > default: > > > return false; > > > -- > > > 2.19.2 > > > >