[PATCH v4 2/5] iio: add power and energy measurement modifiers

[Antoniu Miclaus <antoniu.miclaus@analog.com>]

Add new IIO modifiers to support power and energy measurement devices:

Power modifiers:
- IIO_MOD_ACTIVE: Real power consumed by the load
- IIO_MOD_REACTIVE: Power that oscillates between source and load
- IIO_MOD_APPARENT: Magnitude of complex power
- IIO_MOD_FUND_REACTIVE: Reactive power at fundamental frequency
- IIO_MOD_FACTOR: Power factor (ratio of active to apparent power)

Signal quality modifiers:
- IIO_MOD_RMS: Root Mean Square value

These modifiers enable proper representation of power measurement
devices like energy meters and power analyzers.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
changes in v4:
 - add proper KernelVersion and Contact fields to ABI documentation
 - add detailed description for power factor measurement
 - add altcurrent RMS measurement support
 Documentation/ABI/testing/sysfs-bus-iio | 27 +++++++++++++++++++++++++
 drivers/iio/industrialio-core.c         |  5 +++++
 include/linux/iio/types.h               |  1 +
 include/uapi/linux/iio/types.h          |  4 ++++
 4 files changed, 37 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 2fb2cea4b192..9d283b23d3c0 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -167,7 +167,17 @@ Description:
 		is required is a consistent labeling.  Units after application
 		of scale and offset are millivolts.
 
+What:		/sys/bus/iio/devices/iio:deviceX/in_altvoltageY_rms_raw
+KernelVersion:	6.15
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Raw (unscaled) RMS voltage measurement from
+		channel Y. Units after application of scale and offset are millivolts.
+
 What:		/sys/bus/iio/devices/iio:deviceX/in_powerY_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_powerY_active_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_powerY_reactive_raw
+What:		/sys/bus/iio/devices/iio:deviceX/in_powerY_apparent_raw
 KernelVersion:	4.5
 Contact:	linux-iio@vger.kernel.org
 Description:
@@ -176,6 +186,13 @@ Description:
 		unique to allow association with event codes. Units after
 		application of scale and offset are milliwatts.
 
+What:		/sys/bus/iio/devices/iio:deviceX/in_powerY_powerfactor
+KernelVersion:	6.15
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Power factor measurement from channel Y. Power factor is the
+		ratio of active power to apparent power. The value is unitless.
+
 What:		/sys/bus/iio/devices/iio:deviceX/in_capacitanceY_raw
 KernelVersion:	3.2
 Contact:	linux-iio@vger.kernel.org
@@ -1569,6 +1586,9 @@ Description:
 
 What:		/sys/.../iio:deviceX/in_energy_input
 What:		/sys/.../iio:deviceX/in_energy_raw
+What:		/sys/.../iio:deviceX/in_energyY_active_raw
+What:		/sys/.../iio:deviceX/in_energyY_reactive_raw
+What:		/sys/.../iio:deviceX/in_energyY_apparent_raw
 KernelVersion:	4.0
 Contact:	linux-iio@vger.kernel.org
 Description:
@@ -1707,6 +1727,13 @@ Description:
 		component of the signal while the 'q' channel contains the quadrature
 		component.
 
+What:		/sys/bus/iio/devices/iio:deviceX/in_altcurrentY_rms_raw
+KernelVersion:	6.15
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Raw (unscaled no bias removal etc.) RMS current measurement from
+		channel Y. Units after application of scale and offset are milliamps.
+
 What:		/sys/.../iio:deviceX/in_energy_en
 What:		/sys/.../iio:deviceX/in_distance_en
 What:		/sys/.../iio:deviceX/in_velocity_sqrt(x^2+y^2+z^2)_en
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 8c9098668772..9e372ed38552 100644
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -153,6 +153,10 @@ static const char * const iio_modifier_names[] = {
 	[IIO_MOD_PITCH] = "pitch",
 	[IIO_MOD_YAW] = "yaw",
 	[IIO_MOD_ROLL] = "roll",
+	[IIO_MOD_RMS] = "rms",
+	[IIO_MOD_ACTIVE] = "active",
+	[IIO_MOD_REACTIVE] = "reactive",
+	[IIO_MOD_APPARENT] = "apparent",
 };
 
 /* relies on pairs of these shared then separate */
@@ -190,6 +194,7 @@ static const char * const iio_chan_info_postfix[] = {
 	[IIO_CHAN_INFO_ZEROPOINT] = "zeropoint",
 	[IIO_CHAN_INFO_TROUGH] = "trough_raw",
 	[IIO_CHAN_INFO_CONVDELAY] = "convdelay",
+	[IIO_CHAN_INFO_POWERFACTOR] = "powerfactor",
 };
 /**
  * iio_device_id() - query the unique ID for the device
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index ad2761efcc83..34eebad12d2c 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -70,6 +70,7 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_ZEROPOINT,
 	IIO_CHAN_INFO_TROUGH,
 	IIO_CHAN_INFO_CONVDELAY,
+	IIO_CHAN_INFO_POWERFACTOR,
 };
 
 #endif /* _IIO_TYPES_H_ */
diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
index 3c3cc1497a1e..6d269b844271 100644
--- a/include/uapi/linux/iio/types.h
+++ b/include/uapi/linux/iio/types.h
@@ -109,6 +109,10 @@ enum iio_modifier {
 	IIO_MOD_ROLL,
 	IIO_MOD_LIGHT_UVA,
 	IIO_MOD_LIGHT_UVB,
+	IIO_MOD_RMS,
+	IIO_MOD_ACTIVE,
+	IIO_MOD_REACTIVE,
+	IIO_MOD_APPARENT,
 };
 
 enum iio_event_type {
-- 
2.43.0