[PATCH 0/3] iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[PATCH 0/3] iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[Roan van Dijk]

This series adds support for the Sensirion SCD4x sensor. 

The driver supports continuous reads of temperature, relative humdity and CO2 
concentration. There is an interval of 5 seconds between readings. During
this interval the drivers checks if the sensor has new data available.

The driver is based on the scd30 driver. However, The scd4x has become too 
different to just expand the scd30 driver. I made a new driver instead of
expanding the scd30 driver. I hope I made the right choice by doing so?

Roan van Dijk (3):
  dt-bindings: iio: chemical: sensirion,scd4x: Add yaml description
  MAINTAINERS: Add myself as maintainer of the scd4x driver
  drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

 .../iio/chemical/sensirion,scd4x.yaml         |  45 ++
 MAINTAINERS                                   |   6 +
 drivers/iio/chemical/Kconfig                  |  13 +
 drivers/iio/chemical/Makefile                 |   1 +
 drivers/iio/chemical/scd4x.c                  | 707 ++++++++++++++++++
 5 files changed, 772 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
 create mode 100644 drivers/iio/chemical/scd4x.c

-- 
2.30.2

[PATCH 1/3] dt-bindings: iio: chemical: sensirion,scd4x: Add yaml description

[Roan van Dijk]

Add documentation for the SCD4x carbon dioxide sensor from Sensirion.

Signed-off-by: Roan van Dijk <roan@protonic.nl>
---
 .../iio/chemical/sensirion,scd4x.yaml         | 45 +++++++++++++++++++
 1 file changed, 45 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml

diff --git a/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml b/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
new file mode 100644
index 000000000000..119356933b86
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/chemical/sensirion,scd4x.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Sensirion SCD4X carbon dioxide sensor
+
+maintainers:
+  - Roan van Dijk <roan@protonic.nl>
+
+description: |
+  Air quality sensor capable of measuring co2 concentration, temperature
+  and relative humidity.
+
+properties:
+  compatible:
+    enum:
+      - sensirion,scd4x
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  vdd-supply: true
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    i2c {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      co2-sensor@62 {
+        compatible = "sensirion,scd4x";
+        reg = <0x62>;
+      };
+    };
-- 
2.30.2

[PATCH 2/3] MAINTAINERS: Add myself as maintainer of the scd4x driver

[Roan van Dijk]

Signed-off-by: Roan van Dijk <roan@protonic.nl>
---
 MAINTAINERS | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index c6b8a720c0bc..7398ee8fda22 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16732,6 +16732,12 @@ F:	drivers/iio/chemical/scd30_core.c
 F:	drivers/iio/chemical/scd30_i2c.c
 F:	drivers/iio/chemical/scd30_serial.c
 
+SENSIRION SCD4X CARBON DIOXIDE SENSOR DRIVER
+M:	Roan van Dijk <roan@protonic.nl>
+S:	Maintained
+F:	Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
+F:	drivers/iio/chemical/scd4x.c
+
 SENSIRION SPS30 AIR POLLUTION SENSOR DRIVER
 M:	Tomasz Duszynski <tduszyns@gmail.com>
 S:	Maintained
-- 
2.30.2

[PATCH 3/3] drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[Roan van Dijk]

This is a driver for the SCD4x CO2 sensor from Sensirion. The sensor is
able to measure CO2 concentration, temperature and relative humdity.
The sensor uses a photoacoustic principle for measuring CO2 concentration.
An I2C interface is supported by this driver in order to communicate with
the sensor.

Signed-off-by: Roan van Dijk <roan@protonic.nl>
---
 drivers/iio/chemical/Kconfig  |  13 +
 drivers/iio/chemical/Makefile |   1 +
 drivers/iio/chemical/scd4x.c  | 707 ++++++++++++++++++++++++++++++++++
 3 files changed, 721 insertions(+)
 create mode 100644 drivers/iio/chemical/scd4x.c

diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
index a4920646e9be..ce9ec81d4993 100644
--- a/drivers/iio/chemical/Kconfig
+++ b/drivers/iio/chemical/Kconfig
@@ -118,6 +118,19 @@ config SCD30_SERIAL
 	  To compile this driver as a module, choose M here: the module will
 	  be called scd30_serial.
 
+config SCD4X
+	tristate "SCD4X carbon dioxide sensor driver"
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	depends on I2C
+	select CRC8
+	help
+	  Say Y here to build support for the Sensirion SCD4X sensor with cabon
+	  dioxide, relative humidity and temperature sensing capabilities
+
+	  To compile this driver as a module, choose M here: the module will
+	  be called scd4x.
+
 config SENSIRION_SGP30
 	tristate "Sensirion SGPxx gas sensors"
 	depends on I2C
diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
index 4898690cc155..3a766dd23020 100644
--- a/drivers/iio/chemical/Makefile
+++ b/drivers/iio/chemical/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_PMS7003) += pms7003.o
 obj-$(CONFIG_SCD30_CORE) += scd30_core.o
 obj-$(CONFIG_SCD30_I2C) += scd30_i2c.o
 obj-$(CONFIG_SCD30_SERIAL) += scd30_serial.o
+obj-$(CONFIG_SCD4X) += scd4x.o
 obj-$(CONFIG_SENSIRION_SGP30)	+= sgp30.o
 obj-$(CONFIG_SPS30) += sps30.o
 obj-$(CONFIG_SPS30_I2C) += sps30_i2c.o
diff --git a/drivers/iio/chemical/scd4x.c b/drivers/iio/chemical/scd4x.c
new file mode 100644
index 000000000000..3e3ff62922f6
--- /dev/null
+++ b/drivers/iio/chemical/scd4x.c
@@ -0,0 +1,707 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sensirion SCD4X carbon dioxide sensor i2c driver
+ *
+ * Copyright (C) 2021 Protonic Holland
+ * Author: Roan van Dijk <roan@protonic.nl>
+ *
+ * I2C slave address: 0x62
+ *
+ * Datasheets:
+ * https://www.sensirion.com/file/datasheet_scd4x
+ */
+
+#include <asm/unaligned.h>
+#include <linux/crc8.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/types.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#define SCD4X_CRC8_POLYNOMIAL 0x31
+#define SCD4X_TIMEOUT_ERR 1000
+#define SCD4X_READ_BUF_SIZE 9
+#define SCD4X_COMMAND_BUF_SIZE 2
+#define SCD4X_WRITE_BUF_SIZE 5
+#define SCD4X_FRC_MIN_PPM 400
+#define SCD4X_FRC_MAX_PPM 2000
+
+/*Commands SCD4X*/
+enum scd4x_cmd {
+	CMD_START_MEAS          = 0x21b1,
+	CMD_READ_MEAS           = 0xec05,
+	CMD_STOP_MEAS           = 0x3f86,
+	CMD_SET_TEMP_OFFSET     = 0x241d,
+	CMD_GET_TEMP_OFFSET     = 0x2318,
+	CMD_FRC                 = 0x362f,
+	CMD_SET_ASC             = 0x2416,
+	CMD_GET_ASC             = 0x2313,
+	CMD_GET_DATA_READY      = 0xe4b8,
+};
+
+enum scd4x_channel_idx {
+	SCD4X_CO2,
+	SCD4X_TEMP,
+	SCD4X_HR,
+};
+
+struct scd4x_state {
+	struct i2c_client *client;
+	struct mutex lock;
+	struct device *dev;
+	struct regulator *vdd;
+
+	int irq;
+	uint16_t meas[3];
+};
+
+DECLARE_CRC8_TABLE(scd4x_crc8_table);
+
+static int scd4x_i2c_xfer(struct scd4x_state *state, char *txbuf, int txsize,
+				char *rxbuf, int rxsize)
+{
+	struct i2c_client *client = to_i2c_client(state->dev);
+	int ret;
+
+	ret = i2c_master_send(client, txbuf, txsize);
+
+	if (ret < 0)
+		return ret;
+	if (ret != txsize)
+		return -EIO;
+
+	if (rxsize == 0)
+		return 0;
+
+	ret = i2c_master_recv(client, rxbuf, rxsize);
+	if (ret < 0)
+		return ret;
+	if (ret != rxsize)
+		return -EIO;
+
+	return 0;
+}
+
+static int scd4x_send_command(struct scd4x_state *state, enum scd4x_cmd cmd)
+{
+	char buf[SCD4X_COMMAND_BUF_SIZE];
+	int ret;
+
+	/*
+	 * Measurement needs to be stopped before sending commands.
+	 * Except stop and start command.
+	 */
+	if ((cmd != CMD_STOP_MEAS) & (cmd != CMD_START_MEAS)) {
+
+		ret = scd4x_send_command(state, CMD_STOP_MEAS);
+		if (ret)
+			return ret;
+
+		/* execution time for stopping measurement */
+		msleep_interruptible(500);
+	}
+
+	put_unaligned_be16(cmd, buf);
+	ret = scd4x_i2c_xfer(state, buf, 2, buf, 0);
+	if (ret)
+		return ret;
+
+	if ((cmd != CMD_STOP_MEAS) & (cmd != CMD_START_MEAS)) {
+		ret = scd4x_send_command(state, CMD_START_MEAS);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int scd4x_read(struct scd4x_state *state, enum scd4x_cmd cmd,
+			void *response, int byte_cnt)
+{
+	char buf[SCD4X_READ_BUF_SIZE];
+	char *rsp = response;
+	int i, ret;
+	char crc;
+
+	/*
+	 * Measurement needs to be stopped before sending commands.
+	 * Except for reading measurement and data ready command.
+	 */
+	if ((cmd != CMD_GET_DATA_READY) & (cmd != CMD_READ_MEAS)) {
+		ret = scd4x_send_command(state, CMD_STOP_MEAS);
+		if (ret)
+			return ret;
+
+		/* execution time for stopping measurement */
+		msleep_interruptible(500);
+	}
+
+	put_unaligned_be16(cmd, buf);
+	ret = scd4x_i2c_xfer(state, buf, 2, buf, byte_cnt);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < byte_cnt; i += 3) {
+		crc = crc8(scd4x_crc8_table, buf + i, 2, CRC8_INIT_VALUE);
+		if (crc != buf[i + 2]) {
+			dev_err(state->dev, "CRC error\n");
+			return -EIO;
+		}
+
+		*rsp++ = buf[i];
+		*rsp++ = buf[i + 1];
+	}
+
+	/* start measurement */
+	if ((cmd != CMD_GET_DATA_READY) & (cmd != CMD_READ_MEAS)) {
+		ret = scd4x_send_command(state, CMD_START_MEAS);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int scd4x_write(struct scd4x_state *state, enum scd4x_cmd cmd, uint16_t arg)
+{
+	char buf[SCD4X_WRITE_BUF_SIZE];
+	int ret;
+	char crc;
+
+	put_unaligned_be16(cmd, buf);
+	put_unaligned_be16(arg, buf + 2);
+
+	crc = crc8(scd4x_crc8_table, buf + 2, 2, CRC8_INIT_VALUE);
+	buf[4] = crc;
+
+	/* measurement needs to be stopped before sending commands */
+	ret = scd4x_send_command(state, CMD_STOP_MEAS);
+	if (ret)
+		return ret;
+
+	/* execution time */
+	msleep_interruptible(500);
+
+	ret = scd4x_i2c_xfer(state, buf, SCD4X_WRITE_BUF_SIZE, buf, 0);
+	if (ret)
+		return ret;
+
+	/* start measurement, except for forced calibration command */
+	if (cmd != CMD_FRC) {
+		ret = scd4x_send_command(state, CMD_START_MEAS);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int scd4x_write_and_fetch(struct scd4x_state *state, enum scd4x_cmd cmd,
+				uint16_t arg, void *response, int byte_cnt)
+{
+	struct i2c_client *client = to_i2c_client(state->dev);
+	char buf[SCD4X_READ_BUF_SIZE];
+	char *rsp = response;
+	int i, ret;
+	char crc;
+
+	ret = scd4x_write(state, CMD_FRC, arg);
+	if (ret) {
+		scd4x_send_command(state, CMD_START_MEAS);
+		return ret;
+	}
+
+	/* Execution time */
+	msleep_interruptible(400);
+
+	ret = i2c_master_recv(client, buf, byte_cnt);
+	if (ret < 0)
+		return ret;
+	if (ret != byte_cnt)
+		return -EIO;
+
+	for (i = 0; i < byte_cnt; i += 3) {
+		crc = crc8(scd4x_crc8_table, buf + i, 2, CRC8_INIT_VALUE);
+		if (crc != buf[i + 2]) {
+			dev_err(state->dev, "CRC error\n");
+			scd4x_send_command(state, CMD_START_MEAS);
+			return -EIO;
+		}
+
+		*rsp++ = buf[i];
+		*rsp++ = buf[i + 1];
+	}
+
+	ret = scd4x_send_command(state, CMD_START_MEAS);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int scd4x_read_meas(struct scd4x_state *state)
+{
+	int i, ret;
+
+	ret = scd4x_read(state, CMD_READ_MEAS, state->meas, 9);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(state->meas); i++)
+		state->meas[i] = be16_to_cpu(state->meas[i]);
+	/*
+	 * Temperature and humidity values are convertered and scaled to
+	 * milli deg C and milli percent.
+	 */
+	state->meas[SCD4X_TEMP] = ((175 * state->meas[SCD4X_TEMP]/65536) - 45)*1000;
+	state->meas[SCD4X_HR] = ((100 * state->meas[SCD4X_HR]/65536))*1000;
+
+	return 0;
+}
+
+static int scd4x_wait_meas_poll(struct scd4x_state *state)
+{
+	int tries = 6;
+	int ret;
+
+	do {
+		uint16_t val;
+
+		ret = scd4x_read(state, CMD_GET_DATA_READY, &val, 3);
+		if (ret)
+			return -EIO;
+		val = be16_to_cpu(val);
+
+		/* new measurement available */
+		if (val & 0x7FF)
+			break;
+
+		msleep_interruptible(1000);
+	} while (--tries);
+
+	if (tries == 0) {
+		/* try to start sensor on timeout */
+		ret = scd4x_send_command(state, CMD_START_MEAS);
+		if (ret)
+			dev_err(state->dev, "failed to start measurement: %d\n", ret);
+	}
+
+	return tries ? 0 : -ETIMEDOUT;
+}
+
+static int scd4x_read_poll(struct scd4x_state *state)
+{
+	int ret;
+
+	ret = scd4x_wait_meas_poll(state);
+	if (ret)
+		return ret;
+
+	return scd4x_read_meas(state);
+}
+
+static int scd4x_read_raw(struct iio_dev *indio_dev,
+			struct iio_chan_spec const *chan, int *val,
+			int *val2, long mask)
+{
+	struct scd4x_state *state = iio_priv(indio_dev);
+	int ret;
+	uint16_t tmp;
+
+	mutex_lock(&state->lock);
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+	case IIO_CHAN_INFO_PROCESSED:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			break;
+
+		ret = scd4x_read_poll(state);
+		if (ret) {
+			iio_device_release_direct_mode(indio_dev);
+			break;
+		}
+		*val = state->meas[chan->address];
+		iio_device_release_direct_mode(indio_dev);
+		ret = IIO_VAL_INT;
+		break;
+	case IIO_CHAN_INFO_CALIBBIAS:
+		ret = scd4x_read(state, CMD_GET_TEMP_OFFSET, &tmp, 3);
+		if (ret)
+			break;
+		*val = 175000 * be16_to_cpu(tmp) / 65536;
+		ret = IIO_VAL_INT;
+		break;
+	}
+	mutex_unlock(&state->lock);
+
+	return ret;
+}
+
+static int scd4x_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan,
+				int val, int val2, long mask)
+{
+	struct scd4x_state *state = iio_priv(indio_dev);
+	int ret = 0;
+
+	mutex_lock(&state->lock);
+	switch (mask) {
+	case IIO_CHAN_INFO_CALIBBIAS:
+		val = val * 65536 / 175000;
+		ret = scd4x_write(state, CMD_SET_TEMP_OFFSET, val);
+		if (ret)
+			break;
+	}
+	mutex_unlock(&state->lock);
+
+	return ret;
+}
+
+static ssize_t calibration_auto_enable_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct scd4x_state *state = iio_priv(indio_dev);
+	int ret;
+	uint16_t val;
+
+	mutex_lock(&state->lock);
+	ret = scd4x_read(state, CMD_GET_ASC, &val, 3);
+	mutex_unlock(&state->lock);
+	if (ret)
+		dev_err(dev, "failed to read automatic calibration");
+
+	val = be16_to_cpu(val);
+
+	return ret ?: sprintf(buf, "%d\n", val);
+}
+
+static ssize_t calibration_auto_enable_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct scd4x_state *state = iio_priv(indio_dev);
+	bool val;
+	int ret;
+	uint16_t value;
+
+	ret = kstrtobool(buf, &val);
+	if (ret)
+		return ret;
+
+	value = val;
+
+	mutex_lock(&state->lock);
+	ret = scd4x_write(state, CMD_SET_ASC, value);
+	mutex_unlock(&state->lock);
+	if (ret)
+		dev_err(dev, "failed to set automatic calibration");
+
+	return ret ?: len;
+}
+
+static ssize_t calibration_forced_value_store(struct device *dev,
+					struct device_attribute *attr,
+					const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+	struct scd4x_state *state = iio_priv(indio_dev);
+	uint16_t val, arg;
+	int ret;
+
+	ret = kstrtou16(buf, 0, &arg);
+	if (ret)
+		return ret;
+
+	if (arg < SCD4X_FRC_MIN_PPM || arg > SCD4X_FRC_MAX_PPM)
+		return -EINVAL;
+
+	mutex_lock(&state->lock);
+	ret = scd4x_write_and_fetch(state, CMD_FRC, arg, &val, 3);
+	mutex_unlock(&state->lock);
+
+	if (val == 0xff) {
+		dev_err(state->dev, "forced calibration has failed");
+		return -EINVAL;
+	}
+
+	return ret ?: len;
+}
+
+static IIO_DEVICE_ATTR_RW(calibration_auto_enable, 0);
+static IIO_DEVICE_ATTR_WO(calibration_forced_value, 0);
+
+static struct attribute *scd4x_attrs[] = {
+	&iio_dev_attr_calibration_auto_enable.dev_attr.attr,
+	&iio_dev_attr_calibration_forced_value.dev_attr.attr,
+	NULL
+};
+
+static const struct attribute_group scd4x_attr_group = {
+	.attrs = scd4x_attrs,
+};
+static const struct iio_info scd4x_info = {
+	.attrs = &scd4x_attr_group,
+	.read_raw = scd4x_read_raw,
+	.write_raw = scd4x_write_raw,
+};
+
+static const struct iio_chan_spec scd4x_channels[] = {
+	{
+		.type = IIO_CONCENTRATION,
+		.channel2 = IIO_MOD_CO2,
+		.modified = 1,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.address = SCD4X_CO2,
+		.scan_index = SCD4X_CO2,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_TEMP,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED)|
+				      BIT(IIO_CHAN_INFO_CALIBBIAS),
+		.address = SCD4X_TEMP,
+		.scan_index = SCD4X_TEMP,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+	{
+		.type = IIO_HUMIDITYRELATIVE,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+		.address = SCD4X_HR,
+		.scan_index = SCD4X_HR,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+			.endianness = IIO_BE,
+		},
+	},
+};
+
+int __maybe_unused scd4x_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct scd4x_state *state  = iio_priv(indio_dev);
+	int ret;
+
+	ret = scd4x_send_command(state, CMD_STOP_MEAS);
+	if (ret)
+		return ret;
+
+	return regulator_disable(state->vdd);
+}
+EXPORT_SYMBOL(scd4x_suspend);
+
+int __maybe_unused scd4x_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct scd4x_state *state = iio_priv(indio_dev);
+	int ret;
+
+	ret = regulator_enable(state->vdd);
+	if (ret)
+		return ret;
+
+	return scd4x_send_command(state, CMD_START_MEAS);
+}
+EXPORT_SYMBOL(scd4x_resume);
+
+static void scd4x_stop_meas(void *data)
+{
+	struct scd4x_state *state = data;
+
+	scd4x_send_command(state, CMD_STOP_MEAS);
+}
+
+static void scd4x_disable_regulator(void *data)
+{
+	struct scd4x_state *state = data;
+
+	regulator_disable(state->vdd);
+}
+
+static irqreturn_t scd4x_trigger_handler(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct scd4x_state *state = iio_priv(indio_dev);
+	struct {
+		int data[3];
+		int64_t ts __aligned(8);
+	} scan;
+	int ret;
+
+	mutex_lock(&state->lock);
+	ret = scd4x_read_poll(state);
+	memset(&scan, 0, sizeof(scan));
+	memcpy(scan.data, state->meas, sizeof(state->meas));
+	mutex_unlock(&state->lock);
+	if (ret)
+		goto out;
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
+out:
+	iio_trigger_notify_done(indio_dev->trig);
+	return IRQ_HANDLED;
+}
+
+static int scd4x_set_trigger_state(struct iio_trigger *trig, bool state)
+{
+	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+	struct scd4x_state *st = iio_priv(indio_dev);
+
+	if (state)
+		enable_irq(st->irq);
+	else
+		disable_irq(st->irq);
+
+	return 0;
+}
+
+static const struct iio_trigger_ops scd4x_trigger_ops = {
+	.set_trigger_state = scd4x_set_trigger_state,
+	.validate_device = iio_trigger_validate_own_device,
+};
+
+static int scd4x_setup_trigger(struct iio_dev *indio_dev)
+{
+	struct device *dev = indio_dev->dev.parent;
+	struct iio_trigger *trig;
+	int ret;
+
+	trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
+				      iio_device_id(indio_dev));
+	if (!trig) {
+		dev_err(dev, "failed to allocate trigger\n");
+		return -ENOMEM;
+	}
+
+	trig->ops = &scd4x_trigger_ops;
+	iio_trigger_set_drvdata(trig, indio_dev);
+
+	ret = devm_iio_trigger_register(dev, trig);
+	if (ret)
+		return ret;
+
+	indio_dev->trig = iio_trigger_get(trig);
+
+	return ret;
+}
+
+int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	static const unsigned long scd4x_scan_masks[] = { 0x07, 0x00 };
+	struct device *dev = &client->dev;
+	struct iio_dev *indio_dev;
+	struct scd4x_state *state;
+	int ret;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
+	if (!indio_dev)
+		return -ENOMEM;
+
+	state = iio_priv(indio_dev);
+	mutex_init(&state->lock);
+	state->dev = dev;
+	crc8_populate_msb(scd4x_crc8_table, SCD4X_CRC8_POLYNOMIAL);
+
+	indio_dev->info = &scd4x_info;
+	indio_dev->name = client->name;
+	indio_dev->channels = scd4x_channels;
+	indio_dev->num_channels = ARRAY_SIZE(scd4x_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
+	indio_dev->available_scan_masks = scd4x_scan_masks;
+
+	state->vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(state->vdd))
+		return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
+
+	ret = regulator_enable(state->vdd);
+	if (ret)
+		return ret;
+
+	ret = devm_add_action_or_reset(dev, scd4x_disable_regulator, state);
+	if (ret)
+		return ret;
+
+	ret = scd4x_send_command(state, CMD_STOP_MEAS);
+	if (ret) {
+		dev_err(dev, "failed to stop measurement: %d\n", ret);
+		return ret;
+	}
+
+	/* execution time */
+	msleep_interruptible(500);
+
+	if (state->irq > 0) {
+		ret = scd4x_setup_trigger(indio_dev);
+		if (ret) {
+			dev_err(dev, "failed to setup trigger: %d\n", ret);
+			return ret;
+		}
+	}
+
+	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd4x_trigger_handler, NULL);
+	if (ret)
+		return ret;
+
+	ret = devm_iio_device_register(dev, indio_dev);
+	if (ret) {
+		dev_err(dev, "failed to register iio device\n");
+		return ret;
+	}
+
+	ret = scd4x_send_command(state, CMD_START_MEAS);
+	if (ret) {
+		dev_err(dev, "failed to start measurement: %d\n", ret);
+		return ret;
+	}
+
+	ret = devm_add_action_or_reset(dev, scd4x_stop_meas, state);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL(scd4x_probe);
+
+static const struct of_device_id scd4x_dt_ids[] = {
+	{ .compatible = "sensirion,scd4x" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, scd4x_dt_ids);
+
+static struct i2c_driver scd4x_i2c_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+		.of_match_table = scd4x_dt_ids,
+	},
+	.probe = scd4x_probe,
+};
+module_i2c_driver(scd4x_i2c_driver);
+
+MODULE_AUTHOR("Roan van Dijk <roan@protonic.nl>");
+MODULE_DESCRIPTION("Sensirion SCD4X carbon dioxide sensor core driver");
+MODULE_LICENSE("GPL v2");
-- 
2.30.2

Re: [PATCH 3/3] drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 8016 bytes --]

Hi Roan,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on linux/master linus/master v5.14]
[cannot apply to iio/togreg next-20210831]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: mips-allyesconfig (attached as .config)
compiler: mips-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/605896bbee687d465d4ae58d910878e9b85f0035
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
        git checkout 605896bbee687d465d4ae58d910878e9b85f0035
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/iio/chemical/scd4x.c:503:20: warning: no previous prototype for 'scd4x_suspend' [-Wmissing-prototypes]
     503 | int __maybe_unused scd4x_suspend(struct device *dev)
         |                    ^~~~~~~~~~~~~
>> drivers/iio/chemical/scd4x.c:517:20: warning: no previous prototype for 'scd4x_resume' [-Wmissing-prototypes]
     517 | int __maybe_unused scd4x_resume(struct device *dev)
         |                    ^~~~~~~~~~~~
>> drivers/iio/chemical/scd4x.c:613:5: warning: no previous prototype for 'scd4x_probe' [-Wmissing-prototypes]
     613 | int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
         |     ^~~~~~~~~~~


vim +/scd4x_suspend +503 drivers/iio/chemical/scd4x.c

   502	
 > 503	int __maybe_unused scd4x_suspend(struct device *dev)
   504	{
   505		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   506		struct scd4x_state *state  = iio_priv(indio_dev);
   507		int ret;
   508	
   509		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   510		if (ret)
   511			return ret;
   512	
   513		return regulator_disable(state->vdd);
   514	}
   515	EXPORT_SYMBOL(scd4x_suspend);
   516	
 > 517	int __maybe_unused scd4x_resume(struct device *dev)
   518	{
   519		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   520		struct scd4x_state *state = iio_priv(indio_dev);
   521		int ret;
   522	
   523		ret = regulator_enable(state->vdd);
   524		if (ret)
   525			return ret;
   526	
   527		return scd4x_send_command(state, CMD_START_MEAS);
   528	}
   529	EXPORT_SYMBOL(scd4x_resume);
   530	
   531	static void scd4x_stop_meas(void *data)
   532	{
   533		struct scd4x_state *state = data;
   534	
   535		scd4x_send_command(state, CMD_STOP_MEAS);
   536	}
   537	
   538	static void scd4x_disable_regulator(void *data)
   539	{
   540		struct scd4x_state *state = data;
   541	
   542		regulator_disable(state->vdd);
   543	}
   544	
   545	static irqreturn_t scd4x_trigger_handler(int irq, void *p)
   546	{
   547		struct iio_poll_func *pf = p;
   548		struct iio_dev *indio_dev = pf->indio_dev;
   549		struct scd4x_state *state = iio_priv(indio_dev);
   550		struct {
   551			int data[3];
   552			int64_t ts __aligned(8);
   553		} scan;
   554		int ret;
   555	
   556		mutex_lock(&state->lock);
   557		ret = scd4x_read_poll(state);
   558		memset(&scan, 0, sizeof(scan));
   559		memcpy(scan.data, state->meas, sizeof(state->meas));
   560		mutex_unlock(&state->lock);
   561		if (ret)
   562			goto out;
   563	
   564		iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
   565	out:
   566		iio_trigger_notify_done(indio_dev->trig);
   567		return IRQ_HANDLED;
   568	}
   569	
   570	static int scd4x_set_trigger_state(struct iio_trigger *trig, bool state)
   571	{
   572		struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
   573		struct scd4x_state *st = iio_priv(indio_dev);
   574	
   575		if (state)
   576			enable_irq(st->irq);
   577		else
   578			disable_irq(st->irq);
   579	
   580		return 0;
   581	}
   582	
   583	static const struct iio_trigger_ops scd4x_trigger_ops = {
   584		.set_trigger_state = scd4x_set_trigger_state,
   585		.validate_device = iio_trigger_validate_own_device,
   586	};
   587	
   588	static int scd4x_setup_trigger(struct iio_dev *indio_dev)
   589	{
   590		struct device *dev = indio_dev->dev.parent;
   591		struct iio_trigger *trig;
   592		int ret;
   593	
   594		trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
   595					      iio_device_id(indio_dev));
   596		if (!trig) {
   597			dev_err(dev, "failed to allocate trigger\n");
   598			return -ENOMEM;
   599		}
   600	
   601		trig->ops = &scd4x_trigger_ops;
   602		iio_trigger_set_drvdata(trig, indio_dev);
   603	
   604		ret = devm_iio_trigger_register(dev, trig);
   605		if (ret)
   606			return ret;
   607	
   608		indio_dev->trig = iio_trigger_get(trig);
   609	
   610		return ret;
   611	}
   612	
 > 613	int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   614	{
   615		static const unsigned long scd4x_scan_masks[] = { 0x07, 0x00 };
   616		struct device *dev = &client->dev;
   617		struct iio_dev *indio_dev;
   618		struct scd4x_state *state;
   619		int ret;
   620	
   621		indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
   622		if (!indio_dev)
   623			return -ENOMEM;
   624	
   625		state = iio_priv(indio_dev);
   626		mutex_init(&state->lock);
   627		state->dev = dev;
   628		crc8_populate_msb(scd4x_crc8_table, SCD4X_CRC8_POLYNOMIAL);
   629	
   630		indio_dev->info = &scd4x_info;
   631		indio_dev->name = client->name;
   632		indio_dev->channels = scd4x_channels;
   633		indio_dev->num_channels = ARRAY_SIZE(scd4x_channels);
   634		indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
   635		indio_dev->available_scan_masks = scd4x_scan_masks;
   636	
   637		state->vdd = devm_regulator_get(dev, "vdd");
   638		if (IS_ERR(state->vdd))
   639			return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
   640	
   641		ret = regulator_enable(state->vdd);
   642		if (ret)
   643			return ret;
   644	
   645		ret = devm_add_action_or_reset(dev, scd4x_disable_regulator, state);
   646		if (ret)
   647			return ret;
   648	
   649		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   650		if (ret) {
   651			dev_err(dev, "failed to stop measurement: %d\n", ret);
   652			return ret;
   653		}
   654	
   655		/* execution time */
   656		msleep_interruptible(500);
   657	
   658		if (state->irq > 0) {
   659			ret = scd4x_setup_trigger(indio_dev);
   660			if (ret) {
   661				dev_err(dev, "failed to setup trigger: %d\n", ret);
   662				return ret;
   663			}
   664		}
   665	
   666		ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd4x_trigger_handler, NULL);
   667		if (ret)
   668			return ret;
   669	
   670		ret = devm_iio_device_register(dev, indio_dev);
   671		if (ret) {
   672			dev_err(dev, "failed to register iio device\n");
   673			return ret;
   674		}
   675	
   676		ret = scd4x_send_command(state, CMD_START_MEAS);
   677		if (ret) {
   678			dev_err(dev, "failed to start measurement: %d\n", ret);
   679			return ret;
   680		}
   681	
   682		ret = devm_add_action_or_reset(dev, scd4x_stop_meas, state);
   683		if (ret)
   684			return ret;
   685	
   686		return 0;
   687	}
   688	EXPORT_SYMBOL(scd4x_probe);
   689	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 71019 bytes --]

Re: [PATCH 3/3] drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 8253 bytes --]

Hi Roan,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on linux/master linus/master v5.14]
[cannot apply to iio/togreg next-20210831]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: mips-allyesconfig (attached as .config)
compiler: mips-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/605896bbee687d465d4ae58d910878e9b85f0035
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
        git checkout 605896bbee687d465d4ae58d910878e9b85f0035
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/iio/chemical/scd4x.c:503:20: warning: no previous prototype for 'scd4x_suspend' [-Wmissing-prototypes]
     503 | int __maybe_unused scd4x_suspend(struct device *dev)
         |                    ^~~~~~~~~~~~~
>> drivers/iio/chemical/scd4x.c:517:20: warning: no previous prototype for 'scd4x_resume' [-Wmissing-prototypes]
     517 | int __maybe_unused scd4x_resume(struct device *dev)
         |                    ^~~~~~~~~~~~
>> drivers/iio/chemical/scd4x.c:613:5: warning: no previous prototype for 'scd4x_probe' [-Wmissing-prototypes]
     613 | int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
         |     ^~~~~~~~~~~


vim +/scd4x_suspend +503 drivers/iio/chemical/scd4x.c

   502	
 > 503	int __maybe_unused scd4x_suspend(struct device *dev)
   504	{
   505		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   506		struct scd4x_state *state  = iio_priv(indio_dev);
   507		int ret;
   508	
   509		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   510		if (ret)
   511			return ret;
   512	
   513		return regulator_disable(state->vdd);
   514	}
   515	EXPORT_SYMBOL(scd4x_suspend);
   516	
 > 517	int __maybe_unused scd4x_resume(struct device *dev)
   518	{
   519		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   520		struct scd4x_state *state = iio_priv(indio_dev);
   521		int ret;
   522	
   523		ret = regulator_enable(state->vdd);
   524		if (ret)
   525			return ret;
   526	
   527		return scd4x_send_command(state, CMD_START_MEAS);
   528	}
   529	EXPORT_SYMBOL(scd4x_resume);
   530	
   531	static void scd4x_stop_meas(void *data)
   532	{
   533		struct scd4x_state *state = data;
   534	
   535		scd4x_send_command(state, CMD_STOP_MEAS);
   536	}
   537	
   538	static void scd4x_disable_regulator(void *data)
   539	{
   540		struct scd4x_state *state = data;
   541	
   542		regulator_disable(state->vdd);
   543	}
   544	
   545	static irqreturn_t scd4x_trigger_handler(int irq, void *p)
   546	{
   547		struct iio_poll_func *pf = p;
   548		struct iio_dev *indio_dev = pf->indio_dev;
   549		struct scd4x_state *state = iio_priv(indio_dev);
   550		struct {
   551			int data[3];
   552			int64_t ts __aligned(8);
   553		} scan;
   554		int ret;
   555	
   556		mutex_lock(&state->lock);
   557		ret = scd4x_read_poll(state);
   558		memset(&scan, 0, sizeof(scan));
   559		memcpy(scan.data, state->meas, sizeof(state->meas));
   560		mutex_unlock(&state->lock);
   561		if (ret)
   562			goto out;
   563	
   564		iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
   565	out:
   566		iio_trigger_notify_done(indio_dev->trig);
   567		return IRQ_HANDLED;
   568	}
   569	
   570	static int scd4x_set_trigger_state(struct iio_trigger *trig, bool state)
   571	{
   572		struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
   573		struct scd4x_state *st = iio_priv(indio_dev);
   574	
   575		if (state)
   576			enable_irq(st->irq);
   577		else
   578			disable_irq(st->irq);
   579	
   580		return 0;
   581	}
   582	
   583	static const struct iio_trigger_ops scd4x_trigger_ops = {
   584		.set_trigger_state = scd4x_set_trigger_state,
   585		.validate_device = iio_trigger_validate_own_device,
   586	};
   587	
   588	static int scd4x_setup_trigger(struct iio_dev *indio_dev)
   589	{
   590		struct device *dev = indio_dev->dev.parent;
   591		struct iio_trigger *trig;
   592		int ret;
   593	
   594		trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
   595					      iio_device_id(indio_dev));
   596		if (!trig) {
   597			dev_err(dev, "failed to allocate trigger\n");
   598			return -ENOMEM;
   599		}
   600	
   601		trig->ops = &scd4x_trigger_ops;
   602		iio_trigger_set_drvdata(trig, indio_dev);
   603	
   604		ret = devm_iio_trigger_register(dev, trig);
   605		if (ret)
   606			return ret;
   607	
   608		indio_dev->trig = iio_trigger_get(trig);
   609	
   610		return ret;
   611	}
   612	
 > 613	int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   614	{
   615		static const unsigned long scd4x_scan_masks[] = { 0x07, 0x00 };
   616		struct device *dev = &client->dev;
   617		struct iio_dev *indio_dev;
   618		struct scd4x_state *state;
   619		int ret;
   620	
   621		indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
   622		if (!indio_dev)
   623			return -ENOMEM;
   624	
   625		state = iio_priv(indio_dev);
   626		mutex_init(&state->lock);
   627		state->dev = dev;
   628		crc8_populate_msb(scd4x_crc8_table, SCD4X_CRC8_POLYNOMIAL);
   629	
   630		indio_dev->info = &scd4x_info;
   631		indio_dev->name = client->name;
   632		indio_dev->channels = scd4x_channels;
   633		indio_dev->num_channels = ARRAY_SIZE(scd4x_channels);
   634		indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
   635		indio_dev->available_scan_masks = scd4x_scan_masks;
   636	
   637		state->vdd = devm_regulator_get(dev, "vdd");
   638		if (IS_ERR(state->vdd))
   639			return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
   640	
   641		ret = regulator_enable(state->vdd);
   642		if (ret)
   643			return ret;
   644	
   645		ret = devm_add_action_or_reset(dev, scd4x_disable_regulator, state);
   646		if (ret)
   647			return ret;
   648	
   649		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   650		if (ret) {
   651			dev_err(dev, "failed to stop measurement: %d\n", ret);
   652			return ret;
   653		}
   654	
   655		/* execution time */
   656		msleep_interruptible(500);
   657	
   658		if (state->irq > 0) {
   659			ret = scd4x_setup_trigger(indio_dev);
   660			if (ret) {
   661				dev_err(dev, "failed to setup trigger: %d\n", ret);
   662				return ret;
   663			}
   664		}
   665	
   666		ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd4x_trigger_handler, NULL);
   667		if (ret)
   668			return ret;
   669	
   670		ret = devm_iio_device_register(dev, indio_dev);
   671		if (ret) {
   672			dev_err(dev, "failed to register iio device\n");
   673			return ret;
   674		}
   675	
   676		ret = scd4x_send_command(state, CMD_START_MEAS);
   677		if (ret) {
   678			dev_err(dev, "failed to start measurement: %d\n", ret);
   679			return ret;
   680		}
   681	
   682		ret = devm_add_action_or_reset(dev, scd4x_stop_meas, state);
   683		if (ret)
   684			return ret;
   685	
   686		return 0;
   687	}
   688	EXPORT_SYMBOL(scd4x_probe);
   689	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
[-- Type: application/gzip, Size: 71019 bytes --]

Re: [PATCH 3/3] drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 8724 bytes --]

Hi Roan,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on linux/master linus/master v5.14]
[cannot apply to iio/togreg next-20210831]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: hexagon-randconfig-r036-20210901 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4b1fde8a2b681dad2ce0c082a5d6422caa06b0bc)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/605896bbee687d465d4ae58d910878e9b85f0035
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
        git checkout 605896bbee687d465d4ae58d910878e9b85f0035
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=hexagon 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/iio/chemical/scd4x.c:503:20: warning: no previous prototype for function 'scd4x_suspend' [-Wmissing-prototypes]
   int __maybe_unused scd4x_suspend(struct device *dev)
                      ^
   drivers/iio/chemical/scd4x.c:503:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int __maybe_unused scd4x_suspend(struct device *dev)
   ^
   static 
>> drivers/iio/chemical/scd4x.c:517:20: warning: no previous prototype for function 'scd4x_resume' [-Wmissing-prototypes]
   int __maybe_unused scd4x_resume(struct device *dev)
                      ^
   drivers/iio/chemical/scd4x.c:517:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int __maybe_unused scd4x_resume(struct device *dev)
   ^
   static 
>> drivers/iio/chemical/scd4x.c:613:5: warning: no previous prototype for function 'scd4x_probe' [-Wmissing-prototypes]
   int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
       ^
   drivers/iio/chemical/scd4x.c:613:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   ^
   static 
   3 warnings generated.


vim +/scd4x_suspend +503 drivers/iio/chemical/scd4x.c

   502	
 > 503	int __maybe_unused scd4x_suspend(struct device *dev)
   504	{
   505		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   506		struct scd4x_state *state  = iio_priv(indio_dev);
   507		int ret;
   508	
   509		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   510		if (ret)
   511			return ret;
   512	
   513		return regulator_disable(state->vdd);
   514	}
   515	EXPORT_SYMBOL(scd4x_suspend);
   516	
 > 517	int __maybe_unused scd4x_resume(struct device *dev)
   518	{
   519		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   520		struct scd4x_state *state = iio_priv(indio_dev);
   521		int ret;
   522	
   523		ret = regulator_enable(state->vdd);
   524		if (ret)
   525			return ret;
   526	
   527		return scd4x_send_command(state, CMD_START_MEAS);
   528	}
   529	EXPORT_SYMBOL(scd4x_resume);
   530	
   531	static void scd4x_stop_meas(void *data)
   532	{
   533		struct scd4x_state *state = data;
   534	
   535		scd4x_send_command(state, CMD_STOP_MEAS);
   536	}
   537	
   538	static void scd4x_disable_regulator(void *data)
   539	{
   540		struct scd4x_state *state = data;
   541	
   542		regulator_disable(state->vdd);
   543	}
   544	
   545	static irqreturn_t scd4x_trigger_handler(int irq, void *p)
   546	{
   547		struct iio_poll_func *pf = p;
   548		struct iio_dev *indio_dev = pf->indio_dev;
   549		struct scd4x_state *state = iio_priv(indio_dev);
   550		struct {
   551			int data[3];
   552			int64_t ts __aligned(8);
   553		} scan;
   554		int ret;
   555	
   556		mutex_lock(&state->lock);
   557		ret = scd4x_read_poll(state);
   558		memset(&scan, 0, sizeof(scan));
   559		memcpy(scan.data, state->meas, sizeof(state->meas));
   560		mutex_unlock(&state->lock);
   561		if (ret)
   562			goto out;
   563	
   564		iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
   565	out:
   566		iio_trigger_notify_done(indio_dev->trig);
   567		return IRQ_HANDLED;
   568	}
   569	
   570	static int scd4x_set_trigger_state(struct iio_trigger *trig, bool state)
   571	{
   572		struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
   573		struct scd4x_state *st = iio_priv(indio_dev);
   574	
   575		if (state)
   576			enable_irq(st->irq);
   577		else
   578			disable_irq(st->irq);
   579	
   580		return 0;
   581	}
   582	
   583	static const struct iio_trigger_ops scd4x_trigger_ops = {
   584		.set_trigger_state = scd4x_set_trigger_state,
   585		.validate_device = iio_trigger_validate_own_device,
   586	};
   587	
   588	static int scd4x_setup_trigger(struct iio_dev *indio_dev)
   589	{
   590		struct device *dev = indio_dev->dev.parent;
   591		struct iio_trigger *trig;
   592		int ret;
   593	
   594		trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
   595					      iio_device_id(indio_dev));
   596		if (!trig) {
   597			dev_err(dev, "failed to allocate trigger\n");
   598			return -ENOMEM;
   599		}
   600	
   601		trig->ops = &scd4x_trigger_ops;
   602		iio_trigger_set_drvdata(trig, indio_dev);
   603	
   604		ret = devm_iio_trigger_register(dev, trig);
   605		if (ret)
   606			return ret;
   607	
   608		indio_dev->trig = iio_trigger_get(trig);
   609	
   610		return ret;
   611	}
   612	
 > 613	int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   614	{
   615		static const unsigned long scd4x_scan_masks[] = { 0x07, 0x00 };
   616		struct device *dev = &client->dev;
   617		struct iio_dev *indio_dev;
   618		struct scd4x_state *state;
   619		int ret;
   620	
   621		indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
   622		if (!indio_dev)
   623			return -ENOMEM;
   624	
   625		state = iio_priv(indio_dev);
   626		mutex_init(&state->lock);
   627		state->dev = dev;
   628		crc8_populate_msb(scd4x_crc8_table, SCD4X_CRC8_POLYNOMIAL);
   629	
   630		indio_dev->info = &scd4x_info;
   631		indio_dev->name = client->name;
   632		indio_dev->channels = scd4x_channels;
   633		indio_dev->num_channels = ARRAY_SIZE(scd4x_channels);
   634		indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
   635		indio_dev->available_scan_masks = scd4x_scan_masks;
   636	
   637		state->vdd = devm_regulator_get(dev, "vdd");
   638		if (IS_ERR(state->vdd))
   639			return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
   640	
   641		ret = regulator_enable(state->vdd);
   642		if (ret)
   643			return ret;
   644	
   645		ret = devm_add_action_or_reset(dev, scd4x_disable_regulator, state);
   646		if (ret)
   647			return ret;
   648	
   649		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   650		if (ret) {
   651			dev_err(dev, "failed to stop measurement: %d\n", ret);
   652			return ret;
   653		}
   654	
   655		/* execution time */
   656		msleep_interruptible(500);
   657	
   658		if (state->irq > 0) {
   659			ret = scd4x_setup_trigger(indio_dev);
   660			if (ret) {
   661				dev_err(dev, "failed to setup trigger: %d\n", ret);
   662				return ret;
   663			}
   664		}
   665	
   666		ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd4x_trigger_handler, NULL);
   667		if (ret)
   668			return ret;
   669	
   670		ret = devm_iio_device_register(dev, indio_dev);
   671		if (ret) {
   672			dev_err(dev, "failed to register iio device\n");
   673			return ret;
   674		}
   675	
   676		ret = scd4x_send_command(state, CMD_START_MEAS);
   677		if (ret) {
   678			dev_err(dev, "failed to start measurement: %d\n", ret);
   679			return ret;
   680		}
   681	
   682		ret = devm_add_action_or_reset(dev, scd4x_stop_meas, state);
   683		if (ret)
   684			return ret;
   685	
   686		return 0;
   687	}
   688	EXPORT_SYMBOL(scd4x_probe);
   689	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 26807 bytes --]

Re: [PATCH 3/3] drivers: iio: chemical: Add support for Sensirion SCD4x CO2 sensor

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 8974 bytes --]

Hi Roan,

I love your patch! Perhaps something to improve:

[auto build test WARNING on robh/for-next]
[also build test WARNING on linux/master linus/master v5.14]
[cannot apply to iio/togreg next-20210831]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
base:   https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
config: hexagon-randconfig-r036-20210901 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4b1fde8a2b681dad2ce0c082a5d6422caa06b0bc)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/605896bbee687d465d4ae58d910878e9b85f0035
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Roan-van-Dijk/iio-chemical-Add-support-for-Sensirion-SCD4x-CO2-sensor/20210831-202025
        git checkout 605896bbee687d465d4ae58d910878e9b85f0035
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=hexagon 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/iio/chemical/scd4x.c:503:20: warning: no previous prototype for function 'scd4x_suspend' [-Wmissing-prototypes]
   int __maybe_unused scd4x_suspend(struct device *dev)
                      ^
   drivers/iio/chemical/scd4x.c:503:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int __maybe_unused scd4x_suspend(struct device *dev)
   ^
   static 
>> drivers/iio/chemical/scd4x.c:517:20: warning: no previous prototype for function 'scd4x_resume' [-Wmissing-prototypes]
   int __maybe_unused scd4x_resume(struct device *dev)
                      ^
   drivers/iio/chemical/scd4x.c:517:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int __maybe_unused scd4x_resume(struct device *dev)
   ^
   static 
>> drivers/iio/chemical/scd4x.c:613:5: warning: no previous prototype for function 'scd4x_probe' [-Wmissing-prototypes]
   int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
       ^
   drivers/iio/chemical/scd4x.c:613:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   ^
   static 
   3 warnings generated.


vim +/scd4x_suspend +503 drivers/iio/chemical/scd4x.c

   502	
 > 503	int __maybe_unused scd4x_suspend(struct device *dev)
   504	{
   505		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   506		struct scd4x_state *state  = iio_priv(indio_dev);
   507		int ret;
   508	
   509		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   510		if (ret)
   511			return ret;
   512	
   513		return regulator_disable(state->vdd);
   514	}
   515	EXPORT_SYMBOL(scd4x_suspend);
   516	
 > 517	int __maybe_unused scd4x_resume(struct device *dev)
   518	{
   519		struct iio_dev *indio_dev = dev_get_drvdata(dev);
   520		struct scd4x_state *state = iio_priv(indio_dev);
   521		int ret;
   522	
   523		ret = regulator_enable(state->vdd);
   524		if (ret)
   525			return ret;
   526	
   527		return scd4x_send_command(state, CMD_START_MEAS);
   528	}
   529	EXPORT_SYMBOL(scd4x_resume);
   530	
   531	static void scd4x_stop_meas(void *data)
   532	{
   533		struct scd4x_state *state = data;
   534	
   535		scd4x_send_command(state, CMD_STOP_MEAS);
   536	}
   537	
   538	static void scd4x_disable_regulator(void *data)
   539	{
   540		struct scd4x_state *state = data;
   541	
   542		regulator_disable(state->vdd);
   543	}
   544	
   545	static irqreturn_t scd4x_trigger_handler(int irq, void *p)
   546	{
   547		struct iio_poll_func *pf = p;
   548		struct iio_dev *indio_dev = pf->indio_dev;
   549		struct scd4x_state *state = iio_priv(indio_dev);
   550		struct {
   551			int data[3];
   552			int64_t ts __aligned(8);
   553		} scan;
   554		int ret;
   555	
   556		mutex_lock(&state->lock);
   557		ret = scd4x_read_poll(state);
   558		memset(&scan, 0, sizeof(scan));
   559		memcpy(scan.data, state->meas, sizeof(state->meas));
   560		mutex_unlock(&state->lock);
   561		if (ret)
   562			goto out;
   563	
   564		iio_push_to_buffers_with_timestamp(indio_dev, &scan, iio_get_time_ns(indio_dev));
   565	out:
   566		iio_trigger_notify_done(indio_dev->trig);
   567		return IRQ_HANDLED;
   568	}
   569	
   570	static int scd4x_set_trigger_state(struct iio_trigger *trig, bool state)
   571	{
   572		struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
   573		struct scd4x_state *st = iio_priv(indio_dev);
   574	
   575		if (state)
   576			enable_irq(st->irq);
   577		else
   578			disable_irq(st->irq);
   579	
   580		return 0;
   581	}
   582	
   583	static const struct iio_trigger_ops scd4x_trigger_ops = {
   584		.set_trigger_state = scd4x_set_trigger_state,
   585		.validate_device = iio_trigger_validate_own_device,
   586	};
   587	
   588	static int scd4x_setup_trigger(struct iio_dev *indio_dev)
   589	{
   590		struct device *dev = indio_dev->dev.parent;
   591		struct iio_trigger *trig;
   592		int ret;
   593	
   594		trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
   595					      iio_device_id(indio_dev));
   596		if (!trig) {
   597			dev_err(dev, "failed to allocate trigger\n");
   598			return -ENOMEM;
   599		}
   600	
   601		trig->ops = &scd4x_trigger_ops;
   602		iio_trigger_set_drvdata(trig, indio_dev);
   603	
   604		ret = devm_iio_trigger_register(dev, trig);
   605		if (ret)
   606			return ret;
   607	
   608		indio_dev->trig = iio_trigger_get(trig);
   609	
   610		return ret;
   611	}
   612	
 > 613	int scd4x_probe(struct i2c_client *client, const struct i2c_device_id *id)
   614	{
   615		static const unsigned long scd4x_scan_masks[] = { 0x07, 0x00 };
   616		struct device *dev = &client->dev;
   617		struct iio_dev *indio_dev;
   618		struct scd4x_state *state;
   619		int ret;
   620	
   621		indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
   622		if (!indio_dev)
   623			return -ENOMEM;
   624	
   625		state = iio_priv(indio_dev);
   626		mutex_init(&state->lock);
   627		state->dev = dev;
   628		crc8_populate_msb(scd4x_crc8_table, SCD4X_CRC8_POLYNOMIAL);
   629	
   630		indio_dev->info = &scd4x_info;
   631		indio_dev->name = client->name;
   632		indio_dev->channels = scd4x_channels;
   633		indio_dev->num_channels = ARRAY_SIZE(scd4x_channels);
   634		indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
   635		indio_dev->available_scan_masks = scd4x_scan_masks;
   636	
   637		state->vdd = devm_regulator_get(dev, "vdd");
   638		if (IS_ERR(state->vdd))
   639			return dev_err_probe(dev, PTR_ERR(state->vdd), "failed to get regulator\n");
   640	
   641		ret = regulator_enable(state->vdd);
   642		if (ret)
   643			return ret;
   644	
   645		ret = devm_add_action_or_reset(dev, scd4x_disable_regulator, state);
   646		if (ret)
   647			return ret;
   648	
   649		ret = scd4x_send_command(state, CMD_STOP_MEAS);
   650		if (ret) {
   651			dev_err(dev, "failed to stop measurement: %d\n", ret);
   652			return ret;
   653		}
   654	
   655		/* execution time */
   656		msleep_interruptible(500);
   657	
   658		if (state->irq > 0) {
   659			ret = scd4x_setup_trigger(indio_dev);
   660			if (ret) {
   661				dev_err(dev, "failed to setup trigger: %d\n", ret);
   662				return ret;
   663			}
   664		}
   665	
   666		ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, scd4x_trigger_handler, NULL);
   667		if (ret)
   668			return ret;
   669	
   670		ret = devm_iio_device_register(dev, indio_dev);
   671		if (ret) {
   672			dev_err(dev, "failed to register iio device\n");
   673			return ret;
   674		}
   675	
   676		ret = scd4x_send_command(state, CMD_START_MEAS);
   677		if (ret) {
   678			dev_err(dev, "failed to start measurement: %d\n", ret);
   679			return ret;
   680		}
   681	
   682		ret = devm_add_action_or_reset(dev, scd4x_stop_meas, state);
   683		if (ret)
   684			return ret;
   685	
   686		return 0;
   687	}
   688	EXPORT_SYMBOL(scd4x_probe);
   689	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org

[-- Attachment #2: config.gz --]
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Re: [PATCH 1/3] dt-bindings: iio: chemical: sensirion,scd4x: Add yaml description

[Rob Herring]

On Tue, Aug 31, 2021 at 09:48:26AM +0200, Roan van Dijk wrote:
> Add documentation for the SCD4x carbon dioxide sensor from Sensirion.
> 
> Signed-off-by: Roan van Dijk <roan@protonic.nl>
> ---
>  .../iio/chemical/sensirion,scd4x.yaml         | 45 +++++++++++++++++++
>  1 file changed, 45 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml b/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
> new file mode 100644
> index 000000000000..119356933b86
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/chemical/sensirion,scd4x.yaml
> @@ -0,0 +1,45 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/chemical/sensirion,scd4x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Sensirion SCD4X carbon dioxide sensor
> +
> +maintainers:
> +  - Roan van Dijk <roan@protonic.nl>
> +
> +description: |
> +  Air quality sensor capable of measuring co2 concentration, temperature
> +  and relative humidity.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - sensirion,scd4x

Looks like there's 2 parts with a s/w visible difference (low power 
single shot mode). So this should be 2 compatibles without wildcards.

> +
> +  reg:
> +    maxItems: 1
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  vdd-supply: true
> +
> +required:
> +  - compatible
> +  - reg
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    i2c {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      co2-sensor@62 {
> +        compatible = "sensirion,scd4x";
> +        reg = <0x62>;
> +      };
> +    };
> -- 
> 2.30.2
> 
>