[PATCH v3 0/3] iio: adc: add support for pac1921

[PATCH v3 0/3] iio: adc: add support for pac1921

[Matteo Martelli]

Add iio driver and DT binding for the Microchip PAC1921 Current/Power
monitor.

Implemented most of the features with few limitations listed in the
driver commit message.

Tested with a Pine64 host board connected to a PAC1921 click board [1]
via I2C. The PAC1921 click board embeds the Microchip PAC1921 device
and a 10 mOhms shunt resistor. The PAC1921 datasheet is at [2].

[1]: https://www.mikroe.com/pac1921-click
[2]: https://ww1.microchip.com/downloads/en/DeviceDoc/PAC1921-Data-Sheet-DS20005293E.pdf

Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
---
Changes in v3:
- Add shunt_resistor attribute for current channel
- Generalize shunt_resistor ABI
- Remove specific pac1921 ABI
- Remove resolution and filters controls
- Use scale attributes instead of hwgain attributes to control gains
- Replace integration_num_samples and integration_time attributes with
  oversample_ratio and sampling_frequency
- Consider time to enter integration mode before marking data available
- Add controls for overflow events
- Add select fields in Kconfig
- Refactoring based on Jonathan feedback from v2
- Link to v2: https://lore.kernel.org/r/20240704-iio-pac1921-v2-0-0deb95a48409@gmail.com

Changes in v2:
- DT binding: remove vendor specific gains, add vdd-supply, add
  read/int gpio and fix properties order in example
- Remove parsing of gains from DT
- Handle vdd regulator
- Fix return value in filter_en write handler
- Link to v1: https://lore.kernel.org/r/20240703-iio-pac1921-v1-0-54c47d9180b6@gmail.com

---
Matteo Martelli (3):
      dt-bindings: iio: adc: add binding for pac1921
      iio: ABI: generalize shunt_resistor attribute
      iio: adc: add support for pac1921

 Documentation/ABI/testing/sysfs-bus-iio            |    8 +
 .../ABI/testing/sysfs-bus-iio-adc-max9611          |   17 -
 Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc |    9 -
 .../bindings/iio/adc/microchip,pac1921.yaml        |   71 ++
 MAINTAINERS                                        |    7 +
 drivers/iio/adc/Kconfig                            |   13 +
 drivers/iio/adc/Makefile                           |    1 +
 drivers/iio/adc/pac1921.c                          | 1265 ++++++++++++++++++++
 8 files changed, 1365 insertions(+), 26 deletions(-)
---
base-commit: 1ebab783647a9e3bf357002d5c4ff060c8474a0a
change-id: 20240606-iio-pac1921-77fa0fa3ac11

Best regards,
-- 
Matteo Martelli <matteomartelli3@gmail.com>

[PATCH v3 1/3] dt-bindings: iio: adc: add binding for pac1921

[Matteo Martelli]

Add binging for Microchip PAC1921 Power/Current monitor

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
---
 .../bindings/iio/adc/microchip,pac1921.yaml        | 71 ++++++++++++++++++++++
 1 file changed, 71 insertions(+)

diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
new file mode 100644
index 000000000000..b6f01b79b91d
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/microchip,pac1921.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Microchip PAC1921 High-Side Power/Current Monitor with Anaog Output
+
+maintainers:
+  - Matteo Martelli <matteomartelli3@gmail.com>
+
+description: |
+  The PAC1921 is a power/current monitoring device with an analog output
+  and I2C/SMBus interface.
+
+  Datasheet can be found here:
+  https://ww1.microchip.com/downloads/en/DeviceDoc/PAC1921-Data-Sheet-DS20005293E.pdf
+
+properties:
+  compatible:
+    const: microchip,pac1921
+
+  reg:
+    maxItems: 1
+
+  vdd-supply: true
+
+  "#io-channel-cells":
+    const: 1
+
+  shunt-resistor-micro-ohms:
+    description:
+      Value in micro Ohms of the shunt resistor connected between
+      the SENSE+ and SENSE- inputs, across which the current is measured.
+      Value is needed to compute the scaling of the measured current.
+
+  label:
+    description: Unique name to identify which device this is.
+
+  microchip,read-int-gpios:
+    description:
+      READ/INT input pin to control the current state of the device, either in
+      the INTEGRATE state when driven high, or in the READ state when driven low.
+      When not connected the pin is floating and it can be overridden by the
+      INT_EN register bit after asserting the READ/INT_OVR register bit.
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - vdd-supply
+  - shunt-resistor-micro-ohms
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        adc@4c {
+            compatible = "microchip,pac1921";
+            reg = <0x4c>;
+            vdd-supply = <&vdd>;
+            #io-channel-cells = <1>;
+            label = "vbat";
+            shunt-resistor-micro-ohms = <10000>;
+        };
+    };
+...

-- 
2.45.2

[PATCH v3 2/3] iio: ABI: generalize shunt_resistor attribute

[Matteo Martelli]

Move ABI documentation for custom shunt resistor attributes into the
generic iio documentation file. Exception for pac1934: leave it
untouched since it does not comply with common iio ABI generalization.

Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
---
 Documentation/ABI/testing/sysfs-bus-iio             |  8 ++++++++
 Documentation/ABI/testing/sysfs-bus-iio-adc-max9611 | 17 -----------------
 Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc  |  9 ---------
 3 files changed, 8 insertions(+), 26 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
index 7cee78ad4108..935d67fd1a43 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio
+++ b/Documentation/ABI/testing/sysfs-bus-iio
@@ -2289,3 +2289,11 @@ KernelVersion:	6.7
 Contact:	linux-iio@vger.kernel.org
 Description:
 		List of available timeout value for tap gesture confirmation.
+
+What:		/sys/.../iio:deviceX/in_shunt_resistor
+What:		/sys/.../iio:deviceX/in_current_shunt_resistor
+What:		/sys/.../iio:deviceX/in_power_shunt_resistor
+KernelVersion:	6.10
+Contact:	linux-iio@vger.kernel.org
+Description:
+		The value of current sense resistor in Ohms.
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611 b/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611
deleted file mode 100644
index 6d2d2b094941..000000000000
--- a/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611
+++ /dev/null
@@ -1,17 +0,0 @@
-What:		/sys/bus/iio/devices/iio:deviceX/in_power_shunt_resistor
-Date:		March 2017
-KernelVersion:	4.12
-Contact:	linux-iio@vger.kernel.org
-Description: 	The value of the shunt resistor used to compute power drain on
-                common input voltage pin (RS+). In Ohms.
-
-What:		/sys/bus/iio/devices/iio:deviceX/in_current_shunt_resistor
-Date:		March 2017
-KernelVersion:	4.12
-Contact:	linux-iio@vger.kernel.org
-Description: 	The value of the shunt resistor used to compute current flowing
-                between RS+ and RS- voltage sense inputs. In Ohms.
-
-These attributes describe a single physical component, exposed as two distinct
-attributes as it is used to calculate two different values: power load and
-current flowing between RS+ and RS- inputs.
diff --git a/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc b/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
index 8916f7ec6507..8dbca113112d 100644
--- a/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
+++ b/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
@@ -13,12 +13,3 @@ Description:
 		available for reading data. However, samples can be occasionally skipped
 		or repeated, depending on the beat between the capture and conversion
 		rates.
-
-What:		/sys/bus/iio/devices/iio:deviceX/in_shunt_resistor
-Date:		December 2015
-KernelVersion:	4.4
-Contact:	linux-iio@vger.kernel.org
-Description:
-		The value of the shunt resistor may be known only at runtime fom an
-		eeprom content read by a client application. This attribute allows to
-		set its value in ohms.

-- 
2.45.2

[PATCH v3 3/3] iio: adc: add support for pac1921

[Matteo Martelli]

Add support for Microchip PAC1921 Power/Current monitor.

Implemented features:
* capture of bus voltage, sense voltage, current and power measurements
  in free-run integration mode
* support for both raw and triggered buffer reading
* support for overflow events
* scale attributes to control voltage and current gains
* oversampling ratio attribute to control the number of integration
  samples
* sampling rate attribute that reflects the integration period
* userspace attribute and DT parameter to control shunt resistor
* simple power management support

Limitations:
* operation mode fixed to free-run integration
* READ/INT pin and OUT pin not supported
* no controls for measurement resolutions and filters

Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
---
 MAINTAINERS               |    7 +
 drivers/iio/adc/Kconfig   |   13 +
 drivers/iio/adc/Makefile  |    1 +
 drivers/iio/adc/pac1921.c | 1265 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 1286 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 06ecfa64a39a..eb32f8915202 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14793,6 +14793,13 @@ F:	Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
 F:	drivers/nvmem/microchip-otpc.c
 F:	include/dt-bindings/nvmem/microchip,sama7g5-otpc.h
 
+MICROCHIP PAC1921 POWER/CURRENT MONITOR DRIVER
+M:	Matteo Martelli <matteomartelli3@gmail.com>
+L:	linux-iio@vger.kernel.org
+S:	Supported
+F:	Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
+F:	drivers/iio/adc/pac1921.c
+
 MICROCHIP PAC1934 POWER/ENERGY MONITOR DRIVER
 M:	Marius Cristea <marius.cristea@microchip.com>
 L:	linux-iio@vger.kernel.org
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index f60fe85a30d5..0993253b435c 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -991,6 +991,19 @@ config NPCM_ADC
 	  This driver can also be built as a module. If so, the module
 	  will be called npcm_adc.
 
+config PAC1921
+	tristate "Microchip Technology PAC1921 driver"
+	depends on I2C
+	select REGMAP_I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for Microchip Technology's PAC1921
+	  High-Side Power/Current Monitor with Analog Output.
+
+	  This driver can also be built as a module. If so, the module
+	  will be called pac1921.
+
 config PAC1934
 	tristate "Microchip Technology PAC1934 driver"
 	depends on I2C
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index d370e066544e..5af30eeff262 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -90,6 +90,7 @@ obj-$(CONFIG_MP2629_ADC) += mp2629_adc.o
 obj-$(CONFIG_MXS_LRADC_ADC) += mxs-lradc-adc.o
 obj-$(CONFIG_NAU7802) += nau7802.o
 obj-$(CONFIG_NPCM_ADC) += npcm_adc.o
+obj-$(CONFIG_PAC1921) += pac1921.o
 obj-$(CONFIG_PAC1934) += pac1934.o
 obj-$(CONFIG_PALMAS_GPADC) += palmas_gpadc.o
 obj-$(CONFIG_QCOM_PM8XXX_XOADC) += qcom-pm8xxx-xoadc.o
diff --git a/drivers/iio/adc/pac1921.c b/drivers/iio/adc/pac1921.c
new file mode 100644
index 000000000000..33cc52255e6a
--- /dev/null
+++ b/drivers/iio/adc/pac1921.c
@@ -0,0 +1,1265 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * IIO driver for PAC1921 High-Side Power/Current Monitor
+ *
+ * Copyright (C) 2024 Matteo Martelli <matteomartelli3@gmail.com>
+ */
+
+#include <asm/unaligned.h>
+#include <linux/bitfield.h>
+#include <linux/i2c.h>
+#include <linux/iio/events.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/regmap.h>
+#include <linux/units.h>
+
+/* pac1921 registers */
+#define PAC1921_REG_GAIN_CFG		0x00
+#define PAC1921_REG_INT_CFG		0x01
+#define PAC1921_REG_CONTROL		0x02
+#define PAC1921_REG_VBUS		0x10
+#define PAC1921_REG_VSENSE		0x12
+#define PAC1921_REG_OVERFLOW_STS	0x1C
+#define PAC1921_REG_VPOWER		0x1D
+
+/* pac1921 gain configuration bits */
+#define PAC1921_GAIN_DI_GAIN_MASK	GENMASK(5, 3)
+#define PAC1921_GAIN_DV_GAIN_MASK	GENMASK(2, 0)
+
+/* pac1921 integration configuration bits */
+#define PAC1921_INT_CFG_SMPL_MASK	GENMASK(7, 4)
+#define PAC1921_INT_CFG_VSFEN		BIT(3)
+#define PAC1921_INT_CFG_VBFEN		BIT(2)
+#define PAC1921_INT_CFG_RIOV		BIT(1)
+#define PAC1921_INT_CFG_INTEN		BIT(0)
+
+/* pac1921 control bits */
+#define PAC1921_CONTROL_MXSL_MASK	GENMASK(7, 6)
+enum pac1921_mxsl {
+	PAC1921_MXSL_VPOWER_PIN = 0,
+	PAC1921_MXSL_VSENSE_FREE_RUN = 1,
+	PAC1921_MXSL_VBUS_FREE_RUN = 2,
+	PAC1921_MXSL_VPOWER_FREE_RUN = 3,
+};
+#define PAC1921_CONTROL_SLEEP		BIT(2)
+
+/* pac1921 result registers mask and resolution */
+#define PAC1921_RES_MASK		GENMASK(15, 6)
+#define PAC1921_RES_RESOLUTION		1023
+
+/* pac1921 overflow status bits */
+#define PAC1921_OVERFLOW_VSOV		BIT(2)
+#define PAC1921_OVERFLOW_VBOV		BIT(1)
+#define PAC1921_OVERFLOW_VPOV		BIT(0)
+
+/* pac1921 constants */
+#define PAC1921_MAX_VSENSE_MV		100
+#define PAC1921_MAX_VBUS_V		32
+/* Time to first communication after power up (tINT_T) */
+#define PAC1921_POWERUP_TIME_MS		20
+/* Time from Sleep State to Start of Integration Period (tSLEEP_TO_INT) */
+#define PAC1921_SLEEP_TO_INT_TIME_US	86
+
+/* pac1921 defaults */
+#define PAC1921_DEFAULT_DV_GAIN		0 /* 2^(value): 1x gain (HW default) */
+#define PAC1921_DEFAULT_DI_GAIN		0 /* 2^(value): 1x gain (HW default) */
+#define PAC1921_DEFAULT_NUM_SAMPLES	0 /* 2^(value): 1 sample (HW default) */
+
+/*
+ * Pre-computed scale factors for BUS voltage
+ * format: IIO_VAL_INT_PLUS_NANO
+ * unit: mV
+ *
+ * Vbus scale (mV) = max_vbus (mV) / dv_gain / resolution
+ */
+static const int pac1921_vbus_scales[][2] = {
+	{31, 280547409},	/* dv_gain x1 */
+	{15, 640273704},	/* dv_gain x2 */
+	{7, 820136852},		/* dv_gain x4 */
+	{3, 910068426},		/* dv_gain x8 */
+	{1, 955034213},		/* dv_gain x16 */
+	{0, 977517106}		/* dv_gain x32 */
+};
+
+/*
+ * Pre-computed scales for SENSE voltage
+ * format: IIO_VAL_INT_PLUS_NANO
+ * unit: mV
+ *
+ * Vsense scale (mV) = max_vsense (mV) / di_gain / resolution
+ */
+static const int pac1921_vsense_scales[][2] = {
+	{0, 97751710},		/* di_gain x1 */
+	{0, 48875855},		/* di_gain x2 */
+	{0, 24437927},		/* di_gain x4 */
+	{0, 12218963},		/* di_gain x8 */
+	{0, 6109481},		/* di_gain x16 */
+	{0, 3054740},		/* di_gain x32 */
+	{0, 1527370},		/* di_gain x64 */
+	{0, 763685}		/* di_gain x128 */
+};
+
+/*
+ * Numbers of samples used to integrate measurements at the end of an
+ * integration period.
+ *
+ * Changing the number of samples affects the integration period: higher the
+ * number of samples, longer the integration period.
+ *
+ * These correspond to the oversampling ratios available exposed to userspace.
+ */
+static const int pac1921_int_num_samples[] = {
+	1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048
+};
+
+/*
+ * The integration period depends on the configuration of number of integration
+ * samples, measurement resolution and post filters. The following array
+ * contains integration periods, in microsecs unit, based on table 4-5 from
+ * datasheet considering power integration mode, 14-Bit resolution and post
+ * filters on. Each index corresponds to a specific number of samples from 1
+ * to 2048.
+ */
+static const unsigned int pac1921_int_periods_usecs[] = {
+	2720,		/* 1 sample */
+	4050,		/* 2 samples */
+	6790,		/* 4 samples */
+	12200,		/* 8 samples */
+	23000,		/* 16 samples */
+	46000,		/* 32 samples */
+	92000,		/* 64 samples */
+	184000,		/* 128 samples */
+	368000,		/* 256 samples */
+	736000,		/* 512 samples */
+	1471000,	/* 1024 samples */
+	2941000		/* 2048 samples */
+};
+
+/* pac1921 regmap configuration */
+static const struct regmap_range pac1921_regmap_wr_ranges[] = {
+	regmap_reg_range(PAC1921_REG_GAIN_CFG, PAC1921_REG_CONTROL),
+};
+
+static const struct regmap_access_table pac1921_regmap_wr_table = {
+	.yes_ranges = pac1921_regmap_wr_ranges,
+	.n_yes_ranges = ARRAY_SIZE(pac1921_regmap_wr_ranges),
+};
+
+static const struct regmap_range pac1921_regmap_rd_ranges[] = {
+	regmap_reg_range(PAC1921_REG_GAIN_CFG, PAC1921_REG_CONTROL),
+	regmap_reg_range(PAC1921_REG_VBUS, PAC1921_REG_VPOWER + 1),
+};
+
+static const struct regmap_access_table pac1921_regmap_rd_table = {
+	.yes_ranges = pac1921_regmap_rd_ranges,
+	.n_yes_ranges = ARRAY_SIZE(pac1921_regmap_rd_ranges),
+};
+
+static const struct regmap_config pac1921_regmap_config = {
+	.reg_bits = 8,
+	.val_bits = 8,
+	.rd_table = &pac1921_regmap_rd_table,
+	.wr_table = &pac1921_regmap_wr_table,
+};
+
+enum pac1921_channels {
+	PAC1921_CHAN_VBUS = 0,
+	PAC1921_CHAN_VSENSE = 1,
+	PAC1921_CHAN_CURRENT = 2,
+	PAC1921_CHAN_POWER = 3,
+};
+#define PAC1921_NUM_MEAS_CHANS 4
+
+struct pac1921_priv {
+	struct i2c_client *client;
+	struct regmap *regmap;
+	struct regulator *vdd;
+	struct iio_info iio_info;
+
+	/*
+	 * Synchronize access to private members, and ensure atomicity of
+	 * consecutive regmap operations.
+	 */
+	struct mutex lock;
+
+	u32 rshunt_uohm; /* uOhm */
+	u8 dv_gain;
+	u8 di_gain;
+	u8 n_samples;
+	u8 prev_ovf_flags;
+	u8 ovf_enabled_events;
+
+	bool first_integr_started;
+	bool first_integr_done;
+	unsigned long integr_started_time_jiffies;
+	unsigned int integr_period_usecs;
+
+	int current_scales[ARRAY_SIZE(pac1921_vsense_scales)][2];
+
+	struct {
+		u16 chan[PAC1921_NUM_MEAS_CHANS];
+		s64 timestamp __aligned(8);
+	} scan;
+};
+
+/*
+ * Check if first integration after configuration update has completed.
+ *
+ * Must be called with lock held.
+ */
+static bool pac1921_data_ready(struct pac1921_priv *priv)
+{
+	if (!priv->first_integr_started)
+		return false;
+
+	if (!priv->first_integr_done) {
+		unsigned long t_ready;
+
+		/*
+		 * Data valid after the device entered into integration state,
+		 * considering worst case where the device was in sleep state,
+		 * and completed the first integration period.
+		 */
+		t_ready = priv->integr_started_time_jiffies +
+			  usecs_to_jiffies(PAC1921_SLEEP_TO_INT_TIME_US) +
+			  usecs_to_jiffies(priv->integr_period_usecs);
+
+		if (time_before(jiffies, t_ready))
+			return false;
+
+		priv->first_integr_done = true;
+	}
+
+	return true;
+}
+
+static inline void pac1921_calc_scale(int dividend, int divisor, int *val,
+				      int *val2)
+{
+	s64 tmp;
+
+	tmp = div_s64(dividend * (s64)NANO, divisor);
+	*val = (int)div_s64_rem(tmp, NANO, val2);
+}
+
+/*
+ * Fill the table of scale factors for current
+ * format: IIO_VAL_INT_PLUS_NANO
+ * unit: mA
+ *
+ * Vsense LSB (nV) = max_vsense (nV) * di_gain / resolution
+ * Current scale (mA) = Vsense LSB (nV) / shunt (uOhm)
+ *
+ * Must be called with held lock when updating after first initialization.
+ */
+static void pac1921_calc_current_scales(struct pac1921_priv *priv)
+{
+	for (unsigned int i = 0; i < ARRAY_SIZE(priv->current_scales); i++) {
+		int max = (PAC1921_MAX_VSENSE_MV * MICRO) >> i;
+		int vsense_lsb = DIV_ROUND_CLOSEST(max, PAC1921_RES_RESOLUTION);
+
+		pac1921_calc_scale(vsense_lsb, (int)priv->rshunt_uohm,
+				   &priv->current_scales[i][0],
+				   &priv->current_scales[i][1]);
+	}
+}
+
+/*
+ * Check if overflow occurred and if so, push the corresponding events.
+ *
+ * Must be called with lock held.
+ */
+static int pac1921_check_push_overflow(struct iio_dev *indio_dev, s64 timestamp)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	unsigned int flags;
+	int ret;
+
+	ret = regmap_read(priv->regmap, PAC1921_REG_OVERFLOW_STS, &flags);
+	if (ret)
+		return ret;
+
+	if (flags & PAC1921_OVERFLOW_VBOV &&
+	    !(priv->prev_ovf_flags & PAC1921_OVERFLOW_VBOV) &&
+	    priv->ovf_enabled_events & PAC1921_OVERFLOW_VBOV) {
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(
+				       IIO_VOLTAGE, PAC1921_CHAN_VBUS,
+				       IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING),
+			       timestamp);
+	}
+	if (flags & PAC1921_OVERFLOW_VSOV &&
+	    !(priv->prev_ovf_flags & PAC1921_OVERFLOW_VSOV) &&
+	    priv->ovf_enabled_events & PAC1921_OVERFLOW_VSOV) {
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(
+				       IIO_VOLTAGE, PAC1921_CHAN_VSENSE,
+				       IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING),
+			       timestamp);
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(
+				       IIO_CURRENT, PAC1921_CHAN_CURRENT,
+				       IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING),
+			       timestamp);
+	}
+	if (flags & PAC1921_OVERFLOW_VPOV &&
+	    !(priv->prev_ovf_flags & PAC1921_OVERFLOW_VPOV) &&
+	    priv->ovf_enabled_events & PAC1921_OVERFLOW_VPOV) {
+		iio_push_event(indio_dev,
+			       IIO_UNMOD_EVENT_CODE(
+				       IIO_POWER, PAC1921_CHAN_POWER,
+				       IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING),
+			       timestamp);
+	}
+
+	priv->prev_ovf_flags = (u8)flags;
+
+	return 0;
+}
+
+/*
+ * Read the value from a result register
+ *
+ * Result registers contain the most recent averaged values of Vbus, Vsense and
+ * Vpower. Each value is 10 bits wide and spread across two consecutive 8 bit
+ * registers, with 6 bit LSB zero padding.
+ */
+static int pac1921_read_res(struct pac1921_priv *priv, unsigned long reg,
+			    u16 *val)
+{
+	int ret = regmap_bulk_read(priv->regmap, (unsigned int)reg, val,
+				   sizeof(*val));
+	if (ret)
+		return ret;
+
+	*val = (u16)FIELD_GET(PAC1921_RES_MASK, get_unaligned_be16(val));
+
+	return 0;
+}
+
+static int pac1921_read_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan, int *val,
+			    int *val2, long mask)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+
+	guard(mutex)(&priv->lock);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW: {
+		s64 ts;
+		u16 res_val;
+		int ret;
+
+		if (!pac1921_data_ready(priv))
+			return -EBUSY;
+
+		ts = iio_get_time_ns(indio_dev);
+
+		ret = pac1921_check_push_overflow(indio_dev, ts);
+		if (ret)
+			return ret;
+
+		ret = pac1921_read_res(priv, chan->address, &res_val);
+		if (ret)
+			return ret;
+
+		*val = (int)res_val;
+
+		return IIO_VAL_INT;
+	}
+	case IIO_CHAN_INFO_SCALE:
+		switch (chan->channel) {
+		case PAC1921_CHAN_VBUS:
+			*val = pac1921_vbus_scales[priv->dv_gain][0];
+			*val2 = pac1921_vbus_scales[priv->dv_gain][1];
+			return IIO_VAL_INT_PLUS_NANO;
+
+		case PAC1921_CHAN_VSENSE:
+			*val = pac1921_vsense_scales[priv->di_gain][0];
+			*val2 = pac1921_vsense_scales[priv->di_gain][1];
+			return IIO_VAL_INT_PLUS_NANO;
+
+		case PAC1921_CHAN_CURRENT:
+			*val = priv->current_scales[priv->di_gain][0];
+			*val2 = priv->current_scales[priv->di_gain][1];
+			return IIO_VAL_INT_PLUS_NANO;
+
+		case PAC1921_CHAN_POWER: {
+			/*
+			 * Power scale factor in mW:
+			 * Current scale (mA) * max_vbus (V) / dv_gain
+			 */
+
+			/* Get current scale based on di_gain */
+			int *curr_scale = priv->current_scales[priv->di_gain];
+
+			/* Convert current_scale from INT_PLUS_NANO to INT */
+			s64 tmp = curr_scale[0] * (s64)NANO + curr_scale[1];
+
+			/* Multiply by max_vbus (V) / dv_gain */
+			tmp *= PAC1921_MAX_VBUS_V >> (int)priv->dv_gain;
+
+			/* Convert back to INT_PLUS_NANO */
+			*val = (int)div_s64_rem(tmp, NANO, val2);
+
+			return IIO_VAL_INT_PLUS_NANO;
+		}
+		default:
+			return -EINVAL;
+		}
+
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		*val = pac1921_int_num_samples[priv->n_samples];
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		/*
+		 * The sampling frequency (Hz) is read-only and corresponds to
+		 * how often the device provides integrated measurements into
+		 * the result registers, thus it's 1/integration_period.
+		 * The integration period depends on the number of integration
+		 * samples, measurement resolution and post filters.
+		 *
+		 * 1/(integr_period_usecs/MICRO) = MICRO/integr_period_usecs
+		 */
+		*val = MICRO;
+		*val2 = (int)priv->integr_period_usecs;
+		return IIO_VAL_FRACTIONAL;
+
+	default:
+		return -EINVAL;
+	}
+}
+
+static int pac1921_read_avail(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      const int **vals, int *type, int *length,
+			      long mask)
+{
+	switch (mask) {
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		*type = IIO_VAL_INT;
+		*vals = pac1921_int_num_samples;
+		*length = ARRAY_SIZE(pac1921_int_num_samples);
+		return IIO_AVAIL_LIST;
+	default:
+		return -EINVAL;
+	}
+}
+
+/*
+ * Perform configuration update sequence: set the device into read state, then
+ * write the config register and set the device back into integration state.
+ * Also reset integration start time and mark first integration to be yet
+ * completed.
+ *
+ * Must be called with lock held.
+ */
+static int pac1921_update_cfg_reg(struct pac1921_priv *priv, unsigned int reg,
+				  unsigned int mask, unsigned int val)
+{
+	/* Enter READ state before configuration */
+	int ret = regmap_update_bits(priv->regmap, PAC1921_REG_INT_CFG,
+				     PAC1921_INT_CFG_INTEN, 0);
+	if (ret)
+		return ret;
+
+	/* Update configuration value */
+	ret = regmap_update_bits(priv->regmap, reg, mask, val);
+	if (ret)
+		return ret;
+
+	/* Re-enable integration */
+	ret = regmap_update_bits(priv->regmap, PAC1921_REG_INT_CFG,
+				 PAC1921_INT_CFG_INTEN, PAC1921_INT_CFG_INTEN);
+	if (ret)
+		return ret;
+
+	/*
+	 * Reset integration started time and mark this integration period as
+	 * the first one so that new measurements will be considered as valid
+	 * only at the end of this integration period.
+	 */
+	priv->integr_started_time_jiffies = jiffies;
+	priv->first_integr_done = false;
+
+	return 0;
+}
+
+/*
+ * Retrieve the index of the given scale (represented by scale_val and
+ * scale_val2) from scales_tbl. The returned index (if found) is the log2 of
+ * the gain corresponding to the given scale.
+ *
+ * Must be called with lock held if the scales_tbl can change runtime (e.g. for
+ * the current scales table)
+ */
+static int pac1921_lookup_scale(const int (*const scales_tbl)[2], size_t size,
+				int scale_val, int scale_val2)
+{
+	for (unsigned int i = 0; i < size; i++)
+		if (scales_tbl[i][0] == scale_val &&
+		    scales_tbl[i][1] == scale_val2)
+			return (int)i;
+
+	return -EINVAL;
+}
+
+/*
+ * Configure device with the given gain (only if changed)
+ *
+ * Must be called with lock held.
+ */
+static int pac1921_update_gain(struct pac1921_priv *priv, u8 *priv_val, u8 gain,
+			       unsigned int mask)
+{
+	unsigned int reg_val;
+	int ret;
+
+	if (*priv_val == gain)
+		return 0;
+
+	reg_val = (gain << __ffs(mask)) & mask;
+	ret = pac1921_update_cfg_reg(priv, PAC1921_REG_GAIN_CFG, mask, reg_val);
+	if (ret)
+		return ret;
+
+	*priv_val = gain;
+
+	return 0;
+}
+
+/*
+ * Given a scale factor represented by scale_val and scale_val2 with format
+ * IIO_VAL_INT_PLUS_NANO, find the corresponding gain value and write it to the
+ * device.
+ *
+ * Must be called with lock held.
+ */
+static int pac1921_update_gain_from_scale(struct pac1921_priv *priv,
+					  struct iio_chan_spec const *chan,
+					  int scale_val, int scale_val2)
+{
+	int ret;
+
+	switch (chan->channel) {
+	case PAC1921_CHAN_VBUS:
+		ret = pac1921_lookup_scale(pac1921_vbus_scales,
+					   ARRAY_SIZE(pac1921_vbus_scales),
+					   scale_val, scale_val2);
+		if (ret < 0)
+			return ret;
+
+		return pac1921_update_gain(priv, &priv->dv_gain, (u8)ret,
+					   PAC1921_GAIN_DV_GAIN_MASK);
+	case PAC1921_CHAN_VSENSE:
+		ret = pac1921_lookup_scale(pac1921_vsense_scales,
+					   ARRAY_SIZE(pac1921_vsense_scales),
+					   scale_val, scale_val2);
+		if (ret < 0)
+			return ret;
+
+		return pac1921_update_gain(priv, &priv->di_gain, (u8)ret,
+					   PAC1921_GAIN_DI_GAIN_MASK);
+	case PAC1921_CHAN_CURRENT:
+		ret = pac1921_lookup_scale(priv->current_scales,
+					   ARRAY_SIZE(priv->current_scales),
+					   scale_val, scale_val2);
+		if (ret < 0)
+			return ret;
+
+		return pac1921_update_gain(priv, &priv->di_gain, (u8)ret,
+					   PAC1921_GAIN_DI_GAIN_MASK);
+	default:
+		return -EINVAL;
+	}
+}
+
+/*
+ * Retrieve the index of the given number of samples from the constant table.
+ * The returned index (if found) is the log2 of the given num_samples.
+ */
+static int pac1921_lookup_int_num_samples(int num_samples)
+{
+	for (unsigned int i = 0; i < ARRAY_SIZE(pac1921_int_num_samples); i++)
+		if (pac1921_int_num_samples[i] == num_samples)
+			return (int)i;
+
+	return -EINVAL;
+}
+
+/*
+ * Update the device with the given number of integration samples.
+ *
+ * Must be called with lock held.
+ */
+static int pac1921_update_int_num_samples(struct pac1921_priv *priv,
+					  int num_samples)
+{
+	unsigned int reg_val;
+	u8 n_samples;
+	int ret;
+
+	ret = pac1921_lookup_int_num_samples(num_samples);
+	if (ret < 0)
+		return ret;
+
+	n_samples = (u8)ret;
+
+	if (priv->n_samples == n_samples)
+		return 0;
+
+	reg_val = (u8)FIELD_PREP(PAC1921_INT_CFG_SMPL_MASK, n_samples);
+
+	ret = pac1921_update_cfg_reg(priv, PAC1921_REG_INT_CFG,
+				     PAC1921_INT_CFG_SMPL_MASK, reg_val);
+	if (ret)
+		return ret;
+
+	priv->n_samples = n_samples;
+
+	priv->integr_period_usecs = pac1921_int_periods_usecs[priv->n_samples];
+
+	return 0;
+}
+
+static int pac1921_write_raw_get_fmt(struct iio_dev *indio_dev,
+				     struct iio_chan_spec const *chan,
+				     long info)
+{
+	switch (info) {
+	case IIO_CHAN_INFO_SCALE:
+		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		return IIO_VAL_INT;
+	default:
+		return -EINVAL;
+	}
+}
+
+static int pac1921_write_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan, int val,
+			     int val2, long mask)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+
+	guard(mutex)(&priv->lock);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SCALE:
+		return pac1921_update_gain_from_scale(priv, chan, val, val2);
+	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
+		return pac1921_update_int_num_samples(priv, val);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int pac1921_read_label(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan, char *label)
+{
+	switch (chan->channel) {
+	case PAC1921_CHAN_VBUS:
+		return sprintf(label, "vbus\n");
+	case PAC1921_CHAN_VSENSE:
+		return sprintf(label, "vsense\n");
+	case PAC1921_CHAN_CURRENT:
+		return sprintf(label, "current\n");
+	case PAC1921_CHAN_POWER:
+		return sprintf(label, "power\n");
+	default:
+		return -EINVAL;
+	}
+}
+
+static int pac1921_read_event_config(struct iio_dev *indio_dev,
+				     const struct iio_chan_spec *chan,
+				     enum iio_event_type type,
+				     enum iio_event_direction dir)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+
+	guard(mutex)(&priv->lock);
+
+	switch (chan->channel) {
+	case PAC1921_CHAN_VBUS:
+		return !!(priv->ovf_enabled_events & PAC1921_OVERFLOW_VBOV);
+	case PAC1921_CHAN_VSENSE:
+	case PAC1921_CHAN_CURRENT:
+		return !!(priv->ovf_enabled_events & PAC1921_OVERFLOW_VSOV);
+	case PAC1921_CHAN_POWER:
+		return !!(priv->ovf_enabled_events & PAC1921_OVERFLOW_VPOV);
+	default:
+		return -EINVAL;
+	}
+}
+
+static int pac1921_write_event_config(struct iio_dev *indio_dev,
+				      const struct iio_chan_spec *chan,
+				      enum iio_event_type type,
+				      enum iio_event_direction dir, int state)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	u8 ovf_bit;
+
+	guard(mutex)(&priv->lock);
+
+	switch (chan->channel) {
+	case PAC1921_CHAN_VBUS:
+		ovf_bit = PAC1921_OVERFLOW_VBOV;
+		break;
+	case PAC1921_CHAN_VSENSE:
+	case PAC1921_CHAN_CURRENT:
+		ovf_bit = PAC1921_OVERFLOW_VSOV;
+		break;
+	case PAC1921_CHAN_POWER:
+		ovf_bit = PAC1921_OVERFLOW_VPOV;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (state)
+		priv->ovf_enabled_events |= ovf_bit;
+	else
+		priv->ovf_enabled_events &= ~ovf_bit;
+
+	return 0;
+}
+
+static int pac1921_read_event_value(struct iio_dev *indio_dev,
+				    const struct iio_chan_spec *chan,
+				    enum iio_event_type type,
+				    enum iio_event_direction dir,
+				    enum iio_event_info info, int *val,
+				    int *val2)
+{
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		*val = PAC1921_RES_RESOLUTION;
+		return IIO_VAL_INT;
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_info pac1921_iio = {
+	.read_raw = pac1921_read_raw,
+	.read_avail = pac1921_read_avail,
+	.write_raw = pac1921_write_raw,
+	.write_raw_get_fmt = pac1921_write_raw_get_fmt,
+	.read_label = pac1921_read_label,
+	.read_event_config = pac1921_read_event_config,
+	.write_event_config = pac1921_write_event_config,
+	.read_event_value = pac1921_read_event_value,
+};
+
+static ssize_t pac1921_read_shunt_resistor(struct iio_dev *indio_dev,
+					    uintptr_t private,
+					    const struct iio_chan_spec *chan,
+					    char *buf)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	int vals[2];
+
+	if (chan->channel != PAC1921_CHAN_CURRENT)
+		return -EINVAL;
+
+	guard(mutex)(&priv->lock);
+
+	vals[0] = (int)priv->rshunt_uohm;
+	vals[1] = MICRO;
+
+	return iio_format_value(buf, IIO_VAL_FRACTIONAL, 1, vals);
+}
+
+static ssize_t pac1921_write_shunt_resistor(struct iio_dev *indio_dev,
+					    uintptr_t private,
+					    const struct iio_chan_spec *chan,
+					    const char *buf, size_t len)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	u64 rshunt_uohm;
+	int val, val_fract;
+	int ret;
+
+	if (chan->channel != PAC1921_CHAN_CURRENT)
+		return -EINVAL;
+
+	ret = iio_str_to_fixpoint(buf, 100000, &val, &val_fract);
+	if (ret)
+		return ret;
+
+	rshunt_uohm = (u32)val * MICRO + (u32)val_fract;
+	if (rshunt_uohm == 0 || rshunt_uohm > INT_MAX)
+		return -EINVAL;
+
+	guard(mutex)(&priv->lock);
+
+	priv->rshunt_uohm = (u32)rshunt_uohm;
+
+	pac1921_calc_current_scales(priv);
+
+	return len;
+}
+
+/*
+ * Emit on sysfs the list of available scales contained in scales_tbl
+ *
+ * TODO:: this function can be replaced with iio_format_avail_list() if the
+ * latter will ever be exported.
+ *
+ * Must be called with lock held if the scales_tbl can change runtime (e.g. for
+ * the current scales table)
+ */
+static ssize_t pac1921_format_scale_avail(const int (*const scales_tbl)[2],
+					  size_t size, char *buf)
+{
+	ssize_t len = 0;
+
+	for (unsigned int i = 0; i < size; i++) {
+		if (i != 0) {
+			len += sysfs_emit_at(buf, len, " ");
+			if (len >= PAGE_SIZE)
+				return -EFBIG;
+		}
+		len += sysfs_emit_at(buf, len, "%d.%09d", scales_tbl[i][0],
+				     scales_tbl[i][1]);
+		if (len >= PAGE_SIZE)
+			return -EFBIG;
+	}
+
+	len += sysfs_emit_at(buf, len, "\n");
+	return len;
+}
+
+/*
+ * Read available scales for a specific channel
+ *
+ * NOTE: using extended info insted of iio.read_avail() because access to
+ * current scales must be locked as they depend on shunt resistor which may
+ * change runtime. Caller of iio.read_avail() would access the table unlocked
+ * instead.
+ */
+static ssize_t pac1921_read_scale_avail(struct iio_dev *indio_dev,
+					uintptr_t private,
+					const struct iio_chan_spec *chan,
+					char *buf)
+{
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	const int (*scales_tbl)[2];
+	size_t size;
+
+	switch (chan->channel) {
+	case PAC1921_CHAN_VBUS:
+		scales_tbl = pac1921_vbus_scales;
+		size = ARRAY_SIZE(pac1921_vbus_scales);
+		return pac1921_format_scale_avail(scales_tbl, size, buf);
+
+	case PAC1921_CHAN_VSENSE:
+		scales_tbl = pac1921_vsense_scales;
+		size = ARRAY_SIZE(pac1921_vsense_scales);
+		return pac1921_format_scale_avail(scales_tbl, size, buf);
+
+	case PAC1921_CHAN_CURRENT: {
+		guard(mutex)(&priv->lock);
+		scales_tbl = priv->current_scales;
+		size = ARRAY_SIZE(priv->current_scales);
+		return pac1921_format_scale_avail(scales_tbl, size, buf);
+	}
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct iio_chan_spec_ext_info pac1921_ext_info_rshunt = {
+	.name = "shunt_resistor",
+	.read = pac1921_read_shunt_resistor,
+	.write = pac1921_write_shunt_resistor,
+	.shared = IIO_SEPARATE,
+};
+
+static const struct iio_chan_spec_ext_info pac1921_ext_info_scale_avail = {
+	.name = "scale_available",
+	.read = pac1921_read_scale_avail,
+	.shared = IIO_SEPARATE,
+};
+
+static const struct iio_chan_spec_ext_info pac1921_ext_info_voltage[] = {
+	pac1921_ext_info_scale_avail,
+	{}
+};
+
+static const struct iio_chan_spec_ext_info pac1921_ext_info_current[] = {
+	pac1921_ext_info_scale_avail,
+	pac1921_ext_info_rshunt,
+	{}
+};
+
+static const struct iio_event_spec pac1921_overflow_event[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_shared_by_all = BIT(IIO_EV_INFO_VALUE),
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
+	},
+};
+
+static const struct iio_chan_spec pac1921_channels[] = {
+	{
+		.type = IIO_VOLTAGE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),
+		.info_mask_shared_by_all_available =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+		.channel = PAC1921_CHAN_VBUS,
+		.address = PAC1921_REG_VBUS,
+		.scan_index = PAC1921_CHAN_VBUS,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 10,
+			.storagebits = 16,
+			.endianness = IIO_CPU
+		},
+		.indexed = 1,
+		.event_spec = pac1921_overflow_event,
+		.num_event_specs = ARRAY_SIZE(pac1921_overflow_event),
+		.ext_info = pac1921_ext_info_voltage,
+	},
+	{
+		.type = IIO_VOLTAGE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),
+		.info_mask_shared_by_all_available =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+		.channel = PAC1921_CHAN_VSENSE,
+		.address = PAC1921_REG_VSENSE,
+		.scan_index = PAC1921_CHAN_VSENSE,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 10,
+			.storagebits = 16,
+			.endianness = IIO_CPU
+		},
+		.indexed = 1,
+		.event_spec = pac1921_overflow_event,
+		.num_event_specs = ARRAY_SIZE(pac1921_overflow_event),
+		.ext_info = pac1921_ext_info_voltage,
+	},
+	{
+		.type = IIO_CURRENT,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),
+		.info_mask_shared_by_all_available =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+		.channel = PAC1921_CHAN_CURRENT,
+		.address = PAC1921_REG_VSENSE,
+		.scan_index = PAC1921_CHAN_CURRENT,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 10,
+			.storagebits = 16,
+			.endianness = IIO_CPU
+		},
+		.event_spec = pac1921_overflow_event,
+		.num_event_specs = ARRAY_SIZE(pac1921_overflow_event),
+		.ext_info = pac1921_ext_info_current,
+	},
+	{
+		.type = IIO_POWER,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+				      BIT(IIO_CHAN_INFO_SCALE),
+		.info_mask_shared_by_all =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) |
+			BIT(IIO_CHAN_INFO_SAMP_FREQ),
+		.info_mask_shared_by_all_available =
+			BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+		.channel = PAC1921_CHAN_POWER,
+		.address = PAC1921_REG_VPOWER,
+		.scan_index = PAC1921_CHAN_POWER,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 10,
+			.storagebits = 16,
+			.endianness = IIO_CPU
+		},
+		.event_spec = pac1921_overflow_event,
+		.num_event_specs = ARRAY_SIZE(pac1921_overflow_event),
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(PAC1921_NUM_MEAS_CHANS),
+};
+
+static irqreturn_t pac1921_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *idev = pf->indio_dev;
+	struct pac1921_priv *priv = iio_priv(idev);
+	int ret;
+	int bit;
+	int ch = 0;
+
+	guard(mutex)(&priv->lock);
+
+	if (!pac1921_data_ready(priv))
+		goto done;
+
+	ret = pac1921_check_push_overflow(idev, pf->timestamp);
+	if (ret)
+		goto done;
+
+	for_each_set_bit(bit, idev->active_scan_mask, idev->masklength) {
+		u16 val;
+
+		ret = pac1921_read_res(priv, idev->channels[ch].address, &val);
+		if (ret)
+			goto done;
+
+		priv->scan.chan[ch++] = val;
+	}
+
+	iio_push_to_buffers_with_timestamp(idev, &priv->scan, pf->timestamp);
+
+done:
+	iio_trigger_notify_done(idev->trig);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Initialize device by writing initial configuration and putting it into
+ * integration state.
+ *
+ * Must be called with lock held when called after first initialization
+ * (e.g. from pm resume)
+ */
+static int pac1921_init(struct pac1921_priv *priv)
+{
+	unsigned int val;
+	int ret;
+
+	/* Enter READ state before configuration */
+	ret = regmap_update_bits(priv->regmap, PAC1921_REG_INT_CFG,
+				 PAC1921_INT_CFG_INTEN, 0);
+	if (ret)
+		return ret;
+
+	/* Configure gains, use 14-bits measurement resolution (HW default) */
+	val = (u8)FIELD_PREP(PAC1921_GAIN_DI_GAIN_MASK, priv->di_gain) |
+	      (u8)FIELD_PREP(PAC1921_GAIN_DV_GAIN_MASK, priv->dv_gain);
+	ret = regmap_write(priv->regmap, PAC1921_REG_GAIN_CFG, val);
+	if (ret)
+		return ret;
+
+	/*
+	 * Configure integration:
+	 * - num of integration samples
+	 * - filters enabled (HW default)
+	 * - set READ/INT pin override (RIOV) to control operation mode via
+	 *   register instead of pin
+	 */
+	val = (u8)FIELD_PREP(PAC1921_INT_CFG_SMPL_MASK, priv->n_samples) |
+	      PAC1921_INT_CFG_VSFEN | PAC1921_INT_CFG_VBFEN |
+	      PAC1921_INT_CFG_RIOV;
+	ret = regmap_write(priv->regmap, PAC1921_REG_INT_CFG, val);
+	if (ret)
+		return ret;
+
+	/*
+	 * Init control register:
+	 * - VPower free run integration mode
+	 * - OUT pin full scale range: 3V (HW detault)
+	 * - no timeout, no sleep, no sleep override, no recalc (HW defaults)
+	 */
+	val = (u8)FIELD_PREP(PAC1921_CONTROL_MXSL_MASK,
+			     PAC1921_MXSL_VPOWER_FREE_RUN);
+	ret = regmap_write(priv->regmap, PAC1921_REG_CONTROL, val);
+	if (ret)
+		return ret;
+
+	/* Enable integration */
+	ret = regmap_update_bits(priv->regmap, PAC1921_REG_INT_CFG,
+				 PAC1921_INT_CFG_INTEN, PAC1921_INT_CFG_INTEN);
+	if (ret)
+		return ret;
+
+	priv->first_integr_started = true;
+	priv->integr_started_time_jiffies = jiffies;
+	priv->integr_period_usecs = pac1921_int_periods_usecs[priv->n_samples];
+
+	return 0;
+}
+
+static int pac1921_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	int ret;
+
+	guard(mutex)(&priv->lock);
+
+	priv->first_integr_started = false;
+	priv->first_integr_done = false;
+
+	ret = regmap_update_bits(priv->regmap, PAC1921_REG_INT_CFG,
+				     PAC1921_INT_CFG_INTEN, 0);
+	if (ret)
+		return ret;
+
+	ret = regmap_update_bits(priv->regmap, PAC1921_REG_CONTROL,
+				 PAC1921_CONTROL_SLEEP, PAC1921_CONTROL_SLEEP);
+	if (ret)
+		return ret;
+
+	return regulator_disable(priv->vdd);
+
+}
+
+static int pac1921_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct pac1921_priv *priv = iio_priv(indio_dev);
+	int ret;
+
+	guard(mutex)(&priv->lock);
+
+	ret = regulator_enable(priv->vdd);
+	if (ret)
+		return ret;
+
+	msleep(PAC1921_POWERUP_TIME_MS);
+
+	return pac1921_init(priv);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(pac1921_pm_ops, pac1921_suspend,
+				pac1921_resume);
+
+static void pac1921_regulator_disable(void *data)
+{
+	struct regulator *regulator = data;
+
+	regulator_disable(regulator);
+}
+
+static int pac1921_probe(struct i2c_client *client)
+{
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	struct device *dev = &client->dev;
+	struct pac1921_priv *priv;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	priv = iio_priv(indio_dev);
+	priv->client = client;
+	i2c_set_clientdata(client, indio_dev);
+
+	priv->regmap = devm_regmap_init_i2c(client, &pac1921_regmap_config);
+	if (IS_ERR(priv->regmap))
+		dev_err_probe(dev, (int)PTR_ERR(priv->regmap),
+			      "Cannot initialize register map\n");
+
+	devm_mutex_init(dev, &priv->lock);
+
+	priv->dv_gain = PAC1921_DEFAULT_DV_GAIN;
+	priv->di_gain = PAC1921_DEFAULT_DI_GAIN;
+	priv->n_samples = PAC1921_DEFAULT_NUM_SAMPLES;
+
+	ret = device_property_read_u32(dev, "shunt-resistor-micro-ohms",
+				       &priv->rshunt_uohm);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Cannot read shunt resistor property\n");
+	if (priv->rshunt_uohm == 0 || priv->rshunt_uohm > INT_MAX)
+		return dev_err_probe(dev, -EINVAL,
+				     "Invalid shunt resistor: %u\n",
+				     priv->rshunt_uohm);
+
+	pac1921_calc_current_scales(priv);
+
+	priv->vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(priv->vdd))
+		return dev_err_probe(dev, (int)PTR_ERR(priv->vdd),
+				     "Cannot get vdd regulator\n");
+
+	ret = regulator_enable(priv->vdd);
+	if (ret)
+		return dev_err_probe(dev, ret, "Cannot enable vdd regulator\n");
+
+	ret = devm_add_action_or_reset(dev, pac1921_regulator_disable,
+				       priv->vdd);
+	if (ret)
+		return dev_err_probe(
+			dev, ret,
+			"Cannot add action for vdd regulator disposal\n");
+
+	msleep(PAC1921_POWERUP_TIME_MS);
+
+	ret = pac1921_init(priv);
+	if (ret)
+		return dev_err_probe(dev, ret, "Cannot initialize device\n");
+
+	priv->iio_info = pac1921_iio;
+
+	indio_dev->name = id->name;
+	indio_dev->info = &priv->iio_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels = pac1921_channels;
+	indio_dev->num_channels = ARRAY_SIZE(pac1921_channels);
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
+					      &iio_pollfunc_store_time,
+					      &pac1921_trigger_handler, NULL);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Cannot setup IIO triggered buffer\n");
+
+	ret = devm_iio_device_register(dev, indio_dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Cannot register IIO device\n");
+
+	return 0;
+}
+
+static const struct i2c_device_id pac1921_id[] = {
+	{ .name = "pac1921", 0 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, pac1921_id);
+
+static const struct of_device_id pac1921_of_match[] = {
+	{ .compatible = "microchip,pac1921" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, pac1921_of_match);
+
+static struct i2c_driver pac1921_driver = {
+	.driver	 = {
+		.name = "pac1921",
+		.pm = pm_sleep_ptr(&pac1921_pm_ops),
+		.of_match_table = pac1921_of_match,
+	},
+	.probe = pac1921_probe,
+	.id_table = pac1921_id,
+};
+
+module_i2c_driver(pac1921_driver);
+
+MODULE_AUTHOR("Matteo Martelli <matteomartelli3@gmail.com>");
+MODULE_DESCRIPTION("IIO driver for PAC1921 High-Side Power/Current Monitor");
+MODULE_LICENSE("GPL");

-- 
2.45.2

Re: [PATCH v3 1/3] dt-bindings: iio: adc: add binding for pac1921

[Conor Dooley]

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On Mon, Jul 22, 2024 at 12:03:18PM +0200, Matteo Martelli wrote:
> Add binging for Microchip PAC1921 Power/Current monitor
> 
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
> ---
>  .../bindings/iio/adc/microchip,pac1921.yaml        | 71 ++++++++++++++++++++++
>  1 file changed, 71 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
> new file mode 100644
> index 000000000000..b6f01b79b91d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
> @@ -0,0 +1,71 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/microchip,pac1921.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip PAC1921 High-Side Power/Current Monitor with Anaog Output
> +
> +maintainers:
> +  - Matteo Martelli <matteomartelli3@gmail.com>
> +
> +description: |
> +  The PAC1921 is a power/current monitoring device with an analog output
> +  and I2C/SMBus interface.
> +
> +  Datasheet can be found here:
> +  https://ww1.microchip.com/downloads/en/DeviceDoc/PAC1921-Data-Sheet-DS20005293E.pdf
> +
> +properties:
> +  compatible:
> +    const: microchip,pac1921
> +
> +  reg:
> +    maxItems: 1
> +
> +  vdd-supply: true
> +
> +  "#io-channel-cells":
> +    const: 1
> +
> +  shunt-resistor-micro-ohms:
> +    description:
> +      Value in micro Ohms of the shunt resistor connected between
> +      the SENSE+ and SENSE- inputs, across which the current is measured.
> +      Value is needed to compute the scaling of the measured current.
> +
> +  label:
> +    description: Unique name to identify which device this is.
> +
> +  microchip,read-int-gpios:

IIRC, it is not required to have vendor prefixes on -gpios properties.
Otherwise, this all seems pretty reasonable to me.
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Cheers,
Conor.

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Re: [PATCH v3 1/3] dt-bindings: iio: adc: add binding for pac1921

[Jonathan Cameron]

On Mon, 22 Jul 2024 12:03:18 +0200
Matteo Martelli <matteomartelli3@gmail.com> wrote:

> Add binging for Microchip PAC1921 Power/Current monitor
> 
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
> ---
>  .../bindings/iio/adc/microchip,pac1921.yaml        | 71 ++++++++++++++++++++++
>  1 file changed, 71 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
> new file mode 100644
> index 000000000000..b6f01b79b91d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/microchip,pac1921.yaml
> @@ -0,0 +1,71 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/microchip,pac1921.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Microchip PAC1921 High-Side Power/Current Monitor with Anaog Output
> +
> +maintainers:
> +  - Matteo Martelli <matteomartelli3@gmail.com>
> +
> +description: |
> +  The PAC1921 is a power/current monitoring device with an analog output
> +  and I2C/SMBus interface.
> +
> +  Datasheet can be found here:
> +  https://ww1.microchip.com/downloads/en/DeviceDoc/PAC1921-Data-Sheet-DS20005293E.pdf
> +
> +properties:
> +  compatible:
> +    const: microchip,pac1921
> +
> +  reg:
> +    maxItems: 1
> +
> +  vdd-supply: true
> +
> +  "#io-channel-cells":
> +    const: 1
> +
> +  shunt-resistor-micro-ohms:
> +    description:
> +      Value in micro Ohms of the shunt resistor connected between
> +      the SENSE+ and SENSE- inputs, across which the current is measured.
> +      Value is needed to compute the scaling of the measured current.
> +
> +  label:
> +    description: Unique name to identify which device this is.
> +
> +  microchip,read-int-gpios:
Given I agree with Conor about not needing a vendor prefix for gpios
so you'll be respinning anyway:
Would you mind renaming this to longer form: read-integrate-gpios?

I was briefly assuming it was a INTerrupt pin.

> +    description:
> +      READ/INT input pin to control the current state of the device, either in
> +      the INTEGRATE state when driven high, or in the READ state when driven low.
> +      When not connected the pin is floating and it can be overridden by the
> +      INT_EN register bit after asserting the READ/INT_OVR register bit.
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +  - vdd-supply
> +  - shunt-resistor-micro-ohms
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        adc@4c {
> +            compatible = "microchip,pac1921";
> +            reg = <0x4c>;
> +            vdd-supply = <&vdd>;
> +            #io-channel-cells = <1>;
> +            label = "vbat";
> +            shunt-resistor-micro-ohms = <10000>;
> +        };
> +    };
> +...
> 

Re: [PATCH v3 2/3] iio: ABI: generalize shunt_resistor attribute

[Jonathan Cameron]

On Mon, 22 Jul 2024 12:03:19 +0200
Matteo Martelli <matteomartelli3@gmail.com> wrote:

> Move ABI documentation for custom shunt resistor attributes into the
> generic iio documentation file. Exception for pac1934: leave it
> untouched since it does not comply with common iio ABI generalization.
> 
> Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
This stands on it's own even if the driver needs a minor tweak or two yet.
Hence in the interests of not having to remember I've read it before,
I've queued this patch up;


Applied to the testing branch of iio.git. That will be rebased on rc1 once
available and pushed out as togreg for linux-next to pick it up.

Thanks,

Jonathan

> ---
>  Documentation/ABI/testing/sysfs-bus-iio             |  8 ++++++++
>  Documentation/ABI/testing/sysfs-bus-iio-adc-max9611 | 17 -----------------
>  Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc  |  9 ---------
>  3 files changed, 8 insertions(+), 26 deletions(-)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index 7cee78ad4108..935d67fd1a43 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -2289,3 +2289,11 @@ KernelVersion:	6.7
>  Contact:	linux-iio@vger.kernel.org
>  Description:
>  		List of available timeout value for tap gesture confirmation.
> +
> +What:		/sys/.../iio:deviceX/in_shunt_resistor
> +What:		/sys/.../iio:deviceX/in_current_shunt_resistor
> +What:		/sys/.../iio:deviceX/in_power_shunt_resistor
> +KernelVersion:	6.10
> +Contact:	linux-iio@vger.kernel.org
> +Description:
> +		The value of current sense resistor in Ohms.
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611 b/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611
> deleted file mode 100644
> index 6d2d2b094941..000000000000
> --- a/Documentation/ABI/testing/sysfs-bus-iio-adc-max9611
> +++ /dev/null
> @@ -1,17 +0,0 @@
> -What:		/sys/bus/iio/devices/iio:deviceX/in_power_shunt_resistor
> -Date:		March 2017
> -KernelVersion:	4.12
> -Contact:	linux-iio@vger.kernel.org
> -Description: 	The value of the shunt resistor used to compute power drain on
> -                common input voltage pin (RS+). In Ohms.
> -
> -What:		/sys/bus/iio/devices/iio:deviceX/in_current_shunt_resistor
> -Date:		March 2017
> -KernelVersion:	4.12
> -Contact:	linux-iio@vger.kernel.org
> -Description: 	The value of the shunt resistor used to compute current flowing
> -                between RS+ and RS- voltage sense inputs. In Ohms.
> -
> -These attributes describe a single physical component, exposed as two distinct
> -attributes as it is used to calculate two different values: power load and
> -current flowing between RS+ and RS- inputs.
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc b/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
> index 8916f7ec6507..8dbca113112d 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-ina2xx-adc
> @@ -13,12 +13,3 @@ Description:
>  		available for reading data. However, samples can be occasionally skipped
>  		or repeated, depending on the beat between the capture and conversion
>  		rates.
> -
> -What:		/sys/bus/iio/devices/iio:deviceX/in_shunt_resistor
> -Date:		December 2015
> -KernelVersion:	4.4
> -Contact:	linux-iio@vger.kernel.org
> -Description:
> -		The value of the shunt resistor may be known only at runtime fom an
> -		eeprom content read by a client application. This attribute allows to
> -		set its value in ohms.
> 

Re: [PATCH v3 2/3] iio: ABI: generalize shunt_resistor attribute

[Matteo Martelli]

Jonathan Cameron wrote:
> On Mon, 22 Jul 2024 12:03:19 +0200
> Matteo Martelli <matteomartelli3@gmail.com> wrote:
> 
> > Move ABI documentation for custom shunt resistor attributes into the
> > generic iio documentation file. Exception for pac1934: leave it
> > untouched since it does not comply with common iio ABI generalization.
> > 
> > Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>
> This stands on it's own even if the driver needs a minor tweak or two yet.
> Hence in the interests of not having to remember I've read it before,
> I've queued this patch up;
> 
> 
> Applied to the testing branch of iio.git. That will be rebased on rc1 once
> available and pushed out as togreg for linux-next to pick it up.
> 
> Thanks,
> 
> Jonathan
> 
Thanks Jonathan, should I remove this commit from next version of this patch
series or should I keep posting it?

Best regards,
Matteo

Re: [PATCH v3 3/3] iio: adc: add support for pac1921

[kernel test robot]

Hi Matteo,

kernel test robot noticed the following build errors:

[auto build test ERROR on 1ebab783647a9e3bf357002d5c4ff060c8474a0a]

url:    https://github.com/intel-lab-lkp/linux/commits/Matteo-Martelli/dt-bindings-iio-adc-add-binding-for-pac1921/20240722-183406
base:   1ebab783647a9e3bf357002d5c4ff060c8474a0a
patch link:    https://lore.kernel.org/r/20240722-iio-pac1921-v3-3-05dc9916cb33%40gmail.com
patch subject: [PATCH v3 3/3] iio: adc: add support for pac1921
config: um-randconfig-r051-20240723 (https://download.01.org/0day-ci/archive/20240724/202407240123.tjObpf49-lkp@intel.com/config)
compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240724/202407240123.tjObpf49-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407240123.tjObpf49-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/iio/adc/pac1921.c:892:2: error: initializer element is not constant
     pac1921_ext_info_scale_avail,
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/iio/adc/pac1921.c:892:2: note: (near initialization for 'pac1921_ext_info_voltage[0]')
   drivers/iio/adc/pac1921.c:897:2: error: initializer element is not constant
     pac1921_ext_info_scale_avail,
     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/iio/adc/pac1921.c:897:2: note: (near initialization for 'pac1921_ext_info_current[0]')
   drivers/iio/adc/pac1921.c:898:2: error: initializer element is not constant
     pac1921_ext_info_rshunt,
     ^~~~~~~~~~~~~~~~~~~~~~~
   drivers/iio/adc/pac1921.c:898:2: note: (near initialization for 'pac1921_ext_info_current[1]')


vim +892 drivers/iio/adc/pac1921.c

   890	
   891	static const struct iio_chan_spec_ext_info pac1921_ext_info_voltage[] = {
 > 892		pac1921_ext_info_scale_avail,
   893		{}
   894	};
   895	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH v3 2/3] iio: ABI: generalize shunt_resistor attribute

[Jonathan Cameron]

On Tue, 23 Jul 2024 11:09:11 +0200
Matteo Martelli <matteomartelli3@gmail.com> wrote:

> Jonathan Cameron wrote:
> > On Mon, 22 Jul 2024 12:03:19 +0200
> > Matteo Martelli <matteomartelli3@gmail.com> wrote:
> >   
> > > Move ABI documentation for custom shunt resistor attributes into the
> > > generic iio documentation file. Exception for pac1934: leave it
> > > untouched since it does not comply with common iio ABI generalization.
> > > 
> > > Signed-off-by: Matteo Martelli <matteomartelli3@gmail.com>  
> > This stands on it's own even if the driver needs a minor tweak or two yet.
> > Hence in the interests of not having to remember I've read it before,
> > I've queued this patch up;
> > 
> > 
> > Applied to the testing branch of iio.git. That will be rebased on rc1 once
> > available and pushed out as togreg for linux-next to pick it up.
> > 
> > Thanks,
> > 
> > Jonathan
> >   
> Thanks Jonathan, should I remove this commit from next version of this patch
> series or should I keep posting it?

Please drop it from future versions.

> 
> Best regards,
> Matteo