[PATCH v3 0/4] iio: accel: adxl372: add ADXL371 support

[PATCH v3 0/4] iio: accel: adxl372: add ADXL371 support

[Antoniu Miclaus]

Add support for the Analog Devices ADXL371 3-axis, +-200g MEMS
accelerometer to the existing ADXL372 IIO driver. The ADXL371 shares
the same register map as the ADXL372 but differs in ODR/bandwidth
values, timer scale factors, and has a known silicon anomaly (er001)
that prevents reliable FIFO operation.

Changes in v3:
 - [Patch 1/4] Use designated initializers for adxl372_bw_freq_tbl[]
   for consistency with other frequency tables.
 - [Patch 4/4] Add ADXL371_ODR_NUM to adxl371_odr enum and use it to
   size the ADXL371 frequency tables.

Antoniu Miclaus (4):
  iio: accel: adxl372: introduce chip_info structure
  dt-bindings: iio: accel: adi,adxl372: add ADXL371 compatible
  iio: accel: adxl372: factor out buffer and trigger setup
  iio: accel: adxl372: add support for ADXL371

 .../bindings/iio/accel/adi,adxl372.yaml       |   9 +-
 MAINTAINERS                                   |   5 +-
 drivers/iio/accel/Kconfig                     |  12 +-
 drivers/iio/accel/adxl372.c                   | 295 +++++++++++-------
 drivers/iio/accel/adxl372.h                   |  20 +-
 drivers/iio/accel/adxl372_i2c.c               |  19 +-
 drivers/iio/accel/adxl372_spi.c               |  19 +-
 7 files changed, 245 insertions(+), 134 deletions(-)

-- 
2.43.0

[PATCH v3 1/4] iio: accel: adxl372: introduce chip_info structure

[Antoniu Miclaus]

Introduce a chip_info structure to parameterize device-specific
properties such as ODR/bandwidth frequency tables, activity/inactivity
timer scale factors, and the maximum ODR value. This refactors the
driver to use chip_info lookups instead of hardcoded values, preparing
the driver to support multiple device variants.

The sampling_frequency and filter_low_pass_3db_frequency available
attributes are switched from custom sysfs callbacks to read_avail()
based handling via info_mask_shared_by_type_available. This enforces
consistent formatting through the IIO framework and makes the values
accessible to in-kernel consumers.

The SPI/I2C probe functions are updated to pass a chip_info pointer
instead of a device name string.

No functional change intended.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
Changes in v3:
 - Use designated initializers for adxl372_bw_freq_tbl[] for
   consistency with the other frequency tables.

Changes in v2:
 - Switch sampling_frequency and filter_low_pass_3db_frequency available
   attributes from custom sysfs callbacks to read_avail() with
   info_mask_shared_by_type_available.

 drivers/iio/accel/adxl372.c     | 146 ++++++++++++++++++--------------
 drivers/iio/accel/adxl372.h     |  16 +++-
 drivers/iio/accel/adxl372_i2c.c |  12 ++-
 drivers/iio/accel/adxl372_spi.c |  12 ++-
 4 files changed, 113 insertions(+), 73 deletions(-)

diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
index 28a8793a53b6..d7c580bc9e49 100644
--- a/drivers/iio/accel/adxl372.c
+++ b/drivers/iio/accel/adxl372.c
@@ -180,6 +180,7 @@ enum adxl372_odr {
 	ADXL372_ODR_1600HZ,
 	ADXL372_ODR_3200HZ,
 	ADXL372_ODR_6400HZ,
+	ADXL372_ODR_NUM,
 };
 
 enum adxl372_bandwidth {
@@ -214,14 +215,35 @@ enum adxl372_fifo_mode {
 	ADXL372_FIFO_OLD_SAVED
 };
 
-static const int adxl372_samp_freq_tbl[5] = {
-	400, 800, 1600, 3200, 6400,
+static const int adxl372_samp_freq_tbl[ADXL372_ODR_NUM] = {
+	[ADXL372_ODR_400HZ] = 400,
+	[ADXL372_ODR_800HZ] = 800,
+	[ADXL372_ODR_1600HZ] = 1600,
+	[ADXL372_ODR_3200HZ] = 3200,
+	[ADXL372_ODR_6400HZ] = 6400,
 };
 
-static const int adxl372_bw_freq_tbl[5] = {
-	200, 400, 800, 1600, 3200,
+static const int adxl372_bw_freq_tbl[ADXL372_ODR_NUM] = {
+	[ADXL372_BW_200HZ] = 200,
+	[ADXL372_BW_400HZ] = 400,
+	[ADXL372_BW_800HZ] = 800,
+	[ADXL372_BW_1600HZ] = 1600,
+	[ADXL372_BW_3200HZ] = 3200,
 };
 
+const struct adxl372_chip_info adxl372_chip_info = {
+	.name = "adxl372",
+	.samp_freq_tbl = adxl372_samp_freq_tbl,
+	.bw_freq_tbl = adxl372_bw_freq_tbl,
+	.num_freqs = ARRAY_SIZE(adxl372_samp_freq_tbl),
+	.act_time_scale_us = 3300,
+	.act_time_scale_low_us = 6600,
+	.inact_time_scale_ms = 13,
+	.inact_time_scale_low_ms = 26,
+	.max_odr = ADXL372_ODR_6400HZ,
+};
+EXPORT_SYMBOL_NS_GPL(adxl372_chip_info, "IIO_ADXL372");
+
 struct adxl372_axis_lookup {
 	unsigned int bits;
 	enum adxl372_fifo_format fifo_format;
@@ -260,6 +282,9 @@ static const struct iio_event_spec adxl372_events[] = {
 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
 				    BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
 		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),	\
+	.info_mask_shared_by_type_available =				\
+		BIT(IIO_CHAN_INFO_SAMP_FREQ) |				\
+		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),	\
 	.scan_index = index,						\
 	.scan_type = {							\
 		.sign = 's',						\
@@ -279,6 +304,7 @@ static const struct iio_chan_spec adxl372_channels[] = {
 };
 
 struct adxl372_state {
+	const struct adxl372_chip_info	*chip_info;
 	int				irq;
 	struct device			*dev;
 	struct regmap			*regmap;
@@ -471,13 +497,14 @@ static int adxl372_set_activity_time_ms(struct adxl372_state *st,
 	int ret;
 
 	/*
-	 * 3.3 ms per code is the scale factor of the TIME_ACT register for
-	 * ODR = 6400 Hz. It is 6.6 ms per code for ODR = 3200 Hz and below.
+	 * The scale factor of the TIME_ACT register depends on the ODR.
+	 * A higher scale factor is used at the maximum ODR and a lower
+	 * one at all other rates.
 	 */
-	if (st->odr == ADXL372_ODR_6400HZ)
-		scale_factor = 3300;
+	if (st->odr == st->chip_info->max_odr)
+		scale_factor = st->chip_info->act_time_scale_us;
 	else
-		scale_factor = 6600;
+		scale_factor = st->chip_info->act_time_scale_low_us;
 
 	reg_val = DIV_ROUND_CLOSEST(act_time_ms * 1000, scale_factor);
 
@@ -501,13 +528,14 @@ static int adxl372_set_inactivity_time_ms(struct adxl372_state *st,
 	int ret;
 
 	/*
-	 * 13 ms per code is the scale factor of the TIME_INACT register for
-	 * ODR = 6400 Hz. It is 26 ms per code for ODR = 3200 Hz and below.
+	 * The scale factor of the TIME_INACT register depends on the ODR.
+	 * A higher scale factor is used at the maximum ODR and a lower
+	 * one at all other rates.
 	 */
-	if (st->odr == ADXL372_ODR_6400HZ)
-		scale_factor = 13;
+	if (st->odr == st->chip_info->max_odr)
+		scale_factor = st->chip_info->inact_time_scale_ms;
 	else
-		scale_factor = 26;
+		scale_factor = st->chip_info->inact_time_scale_low_ms;
 
 	res = DIV_ROUND_CLOSEST(inact_time_ms, scale_factor);
 	reg_val_h = (res >> 8) & 0xFF;
@@ -717,7 +745,7 @@ static int adxl372_setup(struct adxl372_state *st)
 	if (ret < 0)
 		return ret;
 
-	ret = adxl372_set_odr(st, ADXL372_ODR_6400HZ);
+	ret = adxl372_set_odr(st, st->chip_info->max_odr);
 	if (ret < 0)
 		return ret;
 
@@ -777,10 +805,10 @@ static int adxl372_read_raw(struct iio_dev *indio_dev,
 		*val2 = ADXL372_USCALE;
 		return IIO_VAL_INT_PLUS_MICRO;
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		*val = adxl372_samp_freq_tbl[st->odr];
+		*val = st->chip_info->samp_freq_tbl[st->odr];
 		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
-		*val = adxl372_bw_freq_tbl[st->bw];
+		*val = st->chip_info->bw_freq_tbl[st->bw];
 		return IIO_VAL_INT;
 	}
 
@@ -796,23 +824,17 @@ static int adxl372_write_raw(struct iio_dev *indio_dev,
 
 	switch (info) {
 	case IIO_CHAN_INFO_SAMP_FREQ:
-		odr_index = adxl372_find_closest_match(adxl372_samp_freq_tbl,
-					ARRAY_SIZE(adxl372_samp_freq_tbl),
-					val);
+		odr_index = adxl372_find_closest_match(st->chip_info->samp_freq_tbl,
+						       st->chip_info->num_freqs,
+						       val);
 		ret = adxl372_set_odr(st, odr_index);
 		if (ret < 0)
 			return ret;
-		/*
-		 * The timer period depends on the ODR selected.
-		 * At 3200 Hz and below, it is 6.6 ms; at 6400 Hz, it is 3.3 ms
-		 */
+		/* Recalculate activity time as the timer period depends on ODR */
 		ret = adxl372_set_activity_time_ms(st, st->act_time_ms);
 		if (ret < 0)
 			return ret;
-		/*
-		 * The timer period depends on the ODR selected.
-		 * At 3200 Hz and below, it is 26 ms; at 6400 Hz, it is 13 ms
-		 */
+		/* Recalculate inactivity time as the timer period depends on ODR */
 		ret = adxl372_set_inactivity_time_ms(st, st->inact_time_ms);
 		if (ret < 0)
 			return ret;
@@ -825,9 +847,9 @@ static int adxl372_write_raw(struct iio_dev *indio_dev,
 
 		return ret;
 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
-		bw_index = adxl372_find_closest_match(adxl372_bw_freq_tbl,
-					ARRAY_SIZE(adxl372_bw_freq_tbl),
-					val);
+		bw_index = adxl372_find_closest_match(st->chip_info->bw_freq_tbl,
+						      st->chip_info->num_freqs,
+						      val);
 		return adxl372_set_bandwidth(st, bw_index);
 	default:
 		return -EINVAL;
@@ -957,24 +979,6 @@ static int adxl372_write_event_config(struct iio_dev *indio_dev, const struct ii
 	return adxl372_set_interrupts(st, st->int1_bitmask, 0);
 }
 
-static ssize_t adxl372_show_filter_freq_avail(struct device *dev,
-					      struct device_attribute *attr,
-					      char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct adxl372_state *st = iio_priv(indio_dev);
-	int i;
-	size_t len = 0;
-
-	for (i = 0; i <= st->odr; i++)
-		len += scnprintf(buf + len, PAGE_SIZE - len,
-				 "%d ", adxl372_bw_freq_tbl[i]);
-
-	buf[len - 1] = '\n';
-
-	return len;
-}
-
 static ssize_t adxl372_get_fifo_enabled(struct device *dev,
 					  struct device_attribute *attr,
 					  char *buf)
@@ -1142,25 +1146,38 @@ static const struct iio_trigger_ops adxl372_peak_data_trigger_ops = {
 	.set_trigger_state = adxl372_peak_dready_trig_set_state,
 };
 
-static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("400 800 1600 3200 6400");
-static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available,
-		       0444, adxl372_show_filter_freq_avail, NULL, 0);
-
-static struct attribute *adxl372_attributes[] = {
-	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
-	&iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,
-	NULL,
-};
+static int adxl372_read_avail(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      const int **vals, int *type, int *length,
+			      long mask)
+{
+	struct adxl372_state *st = iio_priv(indio_dev);
 
-static const struct attribute_group adxl372_attrs_group = {
-	.attrs = adxl372_attributes,
-};
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*vals = st->chip_info->samp_freq_tbl;
+		*type = IIO_VAL_INT;
+		*length = st->chip_info->num_freqs;
+		return IIO_AVAIL_LIST;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		*vals = st->chip_info->bw_freq_tbl;
+		*type = IIO_VAL_INT;
+		/*
+		 * Bandwidth cannot exceed half the sampling frequency
+		 * (Nyquist), so limit available values based on current ODR.
+		 */
+		*length = st->odr + 1;
+		return IIO_AVAIL_LIST;
+	default:
+		return -EINVAL;
+	}
+}
 
 static const struct iio_info adxl372_info = {
 	.validate_trigger = &adxl372_validate_trigger,
-	.attrs = &adxl372_attrs_group,
 	.read_raw = adxl372_read_raw,
 	.write_raw = adxl372_write_raw,
+	.read_avail = adxl372_read_avail,
 	.read_event_config = adxl372_read_event_config,
 	.write_event_config = adxl372_write_event_config,
 	.read_event_value = adxl372_read_event_value,
@@ -1176,7 +1193,7 @@ bool adxl372_readable_noinc_reg(struct device *dev, unsigned int reg)
 EXPORT_SYMBOL_NS_GPL(adxl372_readable_noinc_reg, "IIO_ADXL372");
 
 int adxl372_probe(struct device *dev, struct regmap *regmap,
-		  int irq, const char *name)
+		  int irq, const struct adxl372_chip_info *chip_info)
 {
 	struct iio_dev *indio_dev;
 	struct adxl372_state *st;
@@ -1192,13 +1209,14 @@ int adxl372_probe(struct device *dev, struct regmap *regmap,
 	st->dev = dev;
 	st->regmap = regmap;
 	st->irq = irq;
+	st->chip_info = chip_info;
 
 	mutex_init(&st->threshold_m);
 
 	indio_dev->channels = adxl372_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adxl372_channels);
 	indio_dev->available_scan_masks = adxl372_channel_masks;
-	indio_dev->name = name;
+	indio_dev->name = chip_info->name;
 	indio_dev->info = &adxl372_info;
 	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
 
diff --git a/drivers/iio/accel/adxl372.h b/drivers/iio/accel/adxl372.h
index 80a0aa9714fc..3ce06609446c 100644
--- a/drivers/iio/accel/adxl372.h
+++ b/drivers/iio/accel/adxl372.h
@@ -10,8 +10,22 @@
 
 #define ADXL372_REVID	0x03
 
+struct adxl372_chip_info {
+	const char *name;
+	const int *samp_freq_tbl;
+	const int *bw_freq_tbl;
+	unsigned int num_freqs;
+	unsigned int act_time_scale_us;
+	unsigned int act_time_scale_low_us;
+	unsigned int inact_time_scale_ms;
+	unsigned int inact_time_scale_low_ms;
+	unsigned int max_odr;
+};
+
+extern const struct adxl372_chip_info adxl372_chip_info;
+
 int adxl372_probe(struct device *dev, struct regmap *regmap,
-		  int irq, const char *name);
+		  int irq, const struct adxl372_chip_info *chip_info);
 bool adxl372_readable_noinc_reg(struct device *dev, unsigned int reg);
 
 #endif /* _ADXL372_H_ */
diff --git a/drivers/iio/accel/adxl372_i2c.c b/drivers/iio/accel/adxl372_i2c.c
index 186d4fe9a556..3f97126a87a1 100644
--- a/drivers/iio/accel/adxl372_i2c.c
+++ b/drivers/iio/accel/adxl372_i2c.c
@@ -20,11 +20,15 @@ static const struct regmap_config adxl372_regmap_config = {
 
 static int adxl372_i2c_probe(struct i2c_client *client)
 {
-	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	const struct adxl372_chip_info *chip_info;
 	struct regmap *regmap;
 	unsigned int regval;
 	int ret;
 
+	chip_info = i2c_get_match_data(client);
+	if (!chip_info)
+		return -ENODEV;
+
 	regmap = devm_regmap_init_i2c(client, &adxl372_regmap_config);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
@@ -38,17 +42,17 @@ static int adxl372_i2c_probe(struct i2c_client *client)
 		dev_warn(&client->dev,
 		"I2C might not work properly with other devices on the bus");
 
-	return adxl372_probe(&client->dev, regmap, client->irq, id->name);
+	return adxl372_probe(&client->dev, regmap, client->irq, chip_info);
 }
 
 static const struct i2c_device_id adxl372_i2c_id[] = {
-	{ "adxl372" },
+	{ "adxl372", (kernel_ulong_t)&adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adxl372_i2c_id);
 
 static const struct of_device_id adxl372_of_match[] = {
-	{ .compatible = "adi,adxl372" },
+	{ .compatible = "adi,adxl372", .data = &adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adxl372_of_match);
diff --git a/drivers/iio/accel/adxl372_spi.c b/drivers/iio/accel/adxl372_spi.c
index 39941b519c3b..0e199feb405e 100644
--- a/drivers/iio/accel/adxl372_spi.c
+++ b/drivers/iio/accel/adxl372_spi.c
@@ -22,24 +22,28 @@ static const struct regmap_config adxl372_spi_regmap_config = {
 
 static int adxl372_spi_probe(struct spi_device *spi)
 {
-	const struct spi_device_id *id = spi_get_device_id(spi);
+	const struct adxl372_chip_info *chip_info;
 	struct regmap *regmap;
 
+	chip_info = spi_get_device_match_data(spi);
+	if (!chip_info)
+		return -ENODEV;
+
 	regmap = devm_regmap_init_spi(spi, &adxl372_spi_regmap_config);
 	if (IS_ERR(regmap))
 		return PTR_ERR(regmap);
 
-	return adxl372_probe(&spi->dev, regmap, spi->irq, id->name);
+	return adxl372_probe(&spi->dev, regmap, spi->irq, chip_info);
 }
 
 static const struct spi_device_id adxl372_spi_id[] = {
-	{ "adxl372", 0 },
+	{ "adxl372", (kernel_ulong_t)&adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, adxl372_spi_id);
 
 static const struct of_device_id adxl372_of_match[] = {
-	{ .compatible = "adi,adxl372" },
+	{ .compatible = "adi,adxl372", .data = &adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(of, adxl372_of_match);
-- 
2.43.0

[PATCH v3 2/4] dt-bindings: iio: accel: adi,adxl372: add ADXL371 compatible

[Antoniu Miclaus]

Add the adi,adxl371 compatible string to the ADXL372 binding. The
ADXL371 is a +-200g 3-axis MEMS accelerometer nearly identical to
the ADXL372 in register layout, differing only in ODR/bandwidth
values, timer scale factors, and a silicon anomaly affecting FIFO
operation.

Update the title and description to reflect both devices.

Acked-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
Changes in v3:
 - None.

 .../devicetree/bindings/iio/accel/adi,adxl372.yaml       | 9 ++++++---
 MAINTAINERS                                              | 5 ++++-
 2 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/iio/accel/adi,adxl372.yaml b/Documentation/devicetree/bindings/iio/accel/adi,adxl372.yaml
index 0ba0df46c3a9..02e734946f44 100644
--- a/Documentation/devicetree/bindings/iio/accel/adi,adxl372.yaml
+++ b/Documentation/devicetree/bindings/iio/accel/adi,adxl372.yaml
@@ -4,20 +4,23 @@
 $id: http://devicetree.org/schemas/iio/accel/adi,adxl372.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: Analog Devices ADXL372 3-Axis, +/-(200g) Digital Accelerometer
+title: Analog Devices ADXL371/ADXL372 3-Axis, +/-(200g) Digital Accelerometer
 
 maintainers:
   - Marcelo Schmitt <marcelo.schmitt@analog.com>
   - Nuno Sá <nuno.sa@analog.com>
+  - Antoniu Miclaus <antoniu.miclaus@analog.com>
 
 description: |
-  Analog Devices ADXL372 3-Axis, +/-(200g) Digital Accelerometer that supports
-  both I2C & SPI interfaces
+  Analog Devices ADXL371/ADXL372 3-Axis, +/-(200g) Digital Accelerometer that
+  supports both I2C & SPI interfaces
+    https://www.analog.com/en/products/adxl371.html
     https://www.analog.com/en/products/adxl372.html
 
 properties:
   compatible:
     enum:
+      - adi,adxl371
       - adi,adxl372
 
   reg:
diff --git a/MAINTAINERS b/MAINTAINERS
index dc82a6bd1a61..34a1e1386b66 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -651,8 +651,11 @@ W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/iio/accel/adi,adxl367.yaml
 F:	drivers/iio/accel/adxl367*
 
-ADXL372 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
+ADXL371/ADXL372 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
 M:	Michael Hennerich <michael.hennerich@analog.com>
+M:	Marcelo Schmitt <marcelo.schmitt@analog.com>
+M:	Nuno Sá <nuno.sa@analog.com>
+M:	Antoniu Miclaus <antoniu.miclaus@analog.com>
 S:	Supported
 W:	https://ez.analog.com/linux-software-drivers
 F:	Documentation/devicetree/bindings/iio/accel/adi,adxl372.yaml
-- 
2.43.0

[PATCH v3 3/4] iio: accel: adxl372: factor out buffer and trigger setup

[Antoniu Miclaus]

Extract the triggered buffer, trigger allocation, and IRQ request
logic from adxl372_probe() into a dedicated adxl372_buffer_setup()
helper. This reduces the probe function complexity and prepares for
conditionally disabling buffer support on device variants with
known FIFO issues.

No functional change intended.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
Changes in v3:
 - None.

Changes in v2:
 - Use adxl372_buffer_setup() helper instead of inlining buffer/trigger
   conditional logic in probe.

 drivers/iio/accel/adxl372.c | 94 ++++++++++++++++++++-----------------
 1 file changed, 51 insertions(+), 43 deletions(-)

diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
index d7c580bc9e49..b1d611619e16 100644
--- a/drivers/iio/accel/adxl372.c
+++ b/drivers/iio/accel/adxl372.c
@@ -1192,6 +1192,56 @@ bool adxl372_readable_noinc_reg(struct device *dev, unsigned int reg)
 }
 EXPORT_SYMBOL_NS_GPL(adxl372_readable_noinc_reg, "IIO_ADXL372");
 
+static int adxl372_buffer_setup(struct iio_dev *indio_dev)
+{
+	struct adxl372_state *st = iio_priv(indio_dev);
+	struct device *dev = st->dev;
+	int ret;
+
+	ret = devm_iio_triggered_buffer_setup_ext(dev,
+						  indio_dev, NULL,
+						  adxl372_trigger_handler,
+						  IIO_BUFFER_DIRECTION_IN,
+						  &adxl372_buffer_ops,
+						  adxl372_fifo_attributes);
+	if (ret < 0)
+		return ret;
+
+	if (!st->irq)
+		return 0;
+
+	st->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+						 indio_dev->name,
+						 iio_device_id(indio_dev));
+	if (!st->dready_trig)
+		return -ENOMEM;
+
+	st->peak_datardy_trig = devm_iio_trigger_alloc(dev, "%s-dev%d-peak",
+							indio_dev->name,
+							iio_device_id(indio_dev));
+	if (!st->peak_datardy_trig)
+		return -ENOMEM;
+
+	st->dready_trig->ops = &adxl372_trigger_ops;
+	st->peak_datardy_trig->ops = &adxl372_peak_data_trigger_ops;
+	iio_trigger_set_drvdata(st->dready_trig, indio_dev);
+	iio_trigger_set_drvdata(st->peak_datardy_trig, indio_dev);
+	ret = devm_iio_trigger_register(dev, st->dready_trig);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_iio_trigger_register(dev, st->peak_datardy_trig);
+	if (ret < 0)
+		return ret;
+
+	indio_dev->trig = iio_trigger_get(st->dready_trig);
+
+	return devm_request_irq(dev, st->irq,
+				iio_trigger_generic_data_rdy_poll,
+				IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
+				indio_dev->name, st->dready_trig);
+}
+
 int adxl372_probe(struct device *dev, struct regmap *regmap,
 		  int irq, const struct adxl372_chip_info *chip_info)
 {
@@ -1226,52 +1276,10 @@ int adxl372_probe(struct device *dev, struct regmap *regmap,
 		return ret;
 	}
 
-	ret = devm_iio_triggered_buffer_setup_ext(dev,
-						  indio_dev, NULL,
-						  adxl372_trigger_handler,
-						  IIO_BUFFER_DIRECTION_IN,
-						  &adxl372_buffer_ops,
-						  adxl372_fifo_attributes);
+	ret = adxl372_buffer_setup(indio_dev);
 	if (ret < 0)
 		return ret;
 
-	if (st->irq) {
-		st->dready_trig = devm_iio_trigger_alloc(dev,
-							 "%s-dev%d",
-							 indio_dev->name,
-							 iio_device_id(indio_dev));
-		if (st->dready_trig == NULL)
-			return -ENOMEM;
-
-		st->peak_datardy_trig = devm_iio_trigger_alloc(dev,
-							       "%s-dev%d-peak",
-							       indio_dev->name,
-							       iio_device_id(indio_dev));
-		if (!st->peak_datardy_trig)
-			return -ENOMEM;
-
-		st->dready_trig->ops = &adxl372_trigger_ops;
-		st->peak_datardy_trig->ops = &adxl372_peak_data_trigger_ops;
-		iio_trigger_set_drvdata(st->dready_trig, indio_dev);
-		iio_trigger_set_drvdata(st->peak_datardy_trig, indio_dev);
-		ret = devm_iio_trigger_register(dev, st->dready_trig);
-		if (ret < 0)
-			return ret;
-
-		ret = devm_iio_trigger_register(dev, st->peak_datardy_trig);
-		if (ret < 0)
-			return ret;
-
-		indio_dev->trig = iio_trigger_get(st->dready_trig);
-
-		ret = devm_request_irq(dev, st->irq,
-				       iio_trigger_generic_data_rdy_poll,
-				       IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
-				       indio_dev->name, st->dready_trig);
-		if (ret < 0)
-			return ret;
-	}
-
 	return devm_iio_device_register(dev, indio_dev);
 }
 EXPORT_SYMBOL_NS_GPL(adxl372_probe, "IIO_ADXL372");
-- 
2.43.0

[PATCH v3 4/4] iio: accel: adxl372: add support for ADXL371

[Antoniu Miclaus]

Add support for the Analog Devices ADXL371, a +-200g 3-axis MEMS
accelerometer sharing the same register map as the ADXL372 but with
different ODR values (320/640/1280/2560/5120 Hz vs 400/800/1600/3200/
6400 Hz), different bandwidth values, and different timer scale
factors for activity/inactivity detection.

Due to a silicon anomaly (er001) causing FIFO data misalignment on
all current ADXL371 silicon, FIFO and triggered buffer support is
disabled for the ADXL371 - only direct mode reads are supported.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
Changes in v3:
 - Add ADXL371_ODR_NUM to adxl371_odr enum and use it to size the
   ADXL371 frequency tables.

Changes in v2:
 - Use adxl372_buffer_setup() helper instead of inlining buffer/trigger
   conditional logic in probe.
 - Use designated initializers for ADXL371 frequency tables.

 drivers/iio/accel/Kconfig       | 12 +++---
 drivers/iio/accel/adxl372.c     | 67 ++++++++++++++++++++++++++++-----
 drivers/iio/accel/adxl372.h     |  4 +-
 drivers/iio/accel/adxl372_i2c.c |  7 +++-
 drivers/iio/accel/adxl372_spi.c |  7 +++-
 5 files changed, 77 insertions(+), 20 deletions(-)

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 3d3f8d8673dd..4094299e2ed8 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -158,24 +158,24 @@ config ADXL372
 	select IIO_TRIGGERED_BUFFER
 
 config ADXL372_SPI
-	tristate "Analog Devices ADXL372 3-Axis Accelerometer SPI Driver"
+	tristate "Analog Devices ADXL371/ADXL372 3-Axis Accelerometer SPI Driver"
 	depends on SPI
 	select ADXL372
 	select REGMAP_SPI
 	help
-	  Say yes here to add support for the Analog Devices ADXL372 triaxial
-	  acceleration sensor.
+	  Say yes here to add support for the Analog Devices ADXL371/ADXL372
+	  triaxial acceleration sensor.
 	  To compile this driver as a module, choose M here: the
 	  module will be called adxl372_spi.
 
 config ADXL372_I2C
-	tristate "Analog Devices ADXL372 3-Axis Accelerometer I2C Driver"
+	tristate "Analog Devices ADXL371/ADXL372 3-Axis Accelerometer I2C Driver"
 	depends on I2C
 	select ADXL372
 	select REGMAP_I2C
 	help
-	  Say yes here to add support for the Analog Devices ADXL372 triaxial
-	  acceleration sensor.
+	  Say yes here to add support for the Analog Devices ADXL371/ADXL372
+	  triaxial acceleration sensor.
 	  To compile this driver as a module, choose M here: the
 	  module will be called adxl372_i2c.
 
diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
index b1d611619e16..c5eea32d81db 100644
--- a/drivers/iio/accel/adxl372.c
+++ b/drivers/iio/accel/adxl372.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * ADXL372 3-Axis Digital Accelerometer core driver
+ * ADXL371/ADXL372 3-Axis Digital Accelerometer core driver
  *
  * Copyright 2018 Analog Devices Inc.
  */
@@ -183,6 +183,15 @@ enum adxl372_odr {
 	ADXL372_ODR_NUM,
 };
 
+enum adxl371_odr {
+	ADXL371_ODR_320HZ,
+	ADXL371_ODR_640HZ,
+	ADXL371_ODR_1280HZ,
+	ADXL371_ODR_2560HZ,
+	ADXL371_ODR_5120HZ,
+	ADXL371_ODR_NUM,
+};
+
 enum adxl372_bandwidth {
 	ADXL372_BW_200HZ,
 	ADXL372_BW_400HZ,
@@ -231,6 +240,37 @@ static const int adxl372_bw_freq_tbl[ADXL372_ODR_NUM] = {
 	[ADXL372_BW_3200HZ] = 3200,
 };
 
+static const int adxl371_samp_freq_tbl[ADXL371_ODR_NUM] = {
+	[ADXL371_ODR_320HZ] = 320,
+	[ADXL371_ODR_640HZ] = 640,
+	[ADXL371_ODR_1280HZ] = 1280,
+	[ADXL371_ODR_2560HZ] = 2560,
+	[ADXL371_ODR_5120HZ] = 5120,
+};
+
+static const int adxl371_bw_freq_tbl[ADXL371_ODR_NUM] = {
+	[ADXL371_ODR_320HZ] = 160,
+	[ADXL371_ODR_640HZ] = 320,
+	[ADXL371_ODR_1280HZ] = 640,
+	[ADXL371_ODR_2560HZ] = 1280,
+	[ADXL371_ODR_5120HZ] = 2560,
+};
+
+const struct adxl372_chip_info adxl371_chip_info = {
+	.name = "adxl371",
+	.samp_freq_tbl = adxl371_samp_freq_tbl,
+	.bw_freq_tbl = adxl371_bw_freq_tbl,
+	.num_freqs = ARRAY_SIZE(adxl371_samp_freq_tbl),
+	.act_time_scale_us = 4125,
+	.act_time_scale_low_us = 8250,
+	.inact_time_scale_ms = 16,
+	.inact_time_scale_low_ms = 32,
+	.max_odr = ADXL371_ODR_5120HZ,
+	/* Silicon erratum (er001) causes FIFO data misalignment on ADXL371 */
+	.fifo_supported = false,
+};
+EXPORT_SYMBOL_NS_GPL(adxl371_chip_info, "IIO_ADXL372");
+
 const struct adxl372_chip_info adxl372_chip_info = {
 	.name = "adxl372",
 	.samp_freq_tbl = adxl372_samp_freq_tbl,
@@ -241,6 +281,7 @@ const struct adxl372_chip_info adxl372_chip_info = {
 	.inact_time_scale_ms = 13,
 	.inact_time_scale_low_ms = 26,
 	.max_odr = ADXL372_ODR_6400HZ,
+	.fifo_supported = true,
 };
 EXPORT_SYMBOL_NS_GPL(adxl372_chip_info, "IIO_ADXL372");
 
@@ -1217,8 +1258,8 @@ static int adxl372_buffer_setup(struct iio_dev *indio_dev)
 		return -ENOMEM;
 
 	st->peak_datardy_trig = devm_iio_trigger_alloc(dev, "%s-dev%d-peak",
-							indio_dev->name,
-							iio_device_id(indio_dev));
+						       indio_dev->name,
+						       iio_device_id(indio_dev));
 	if (!st->peak_datardy_trig)
 		return -ENOMEM;
 
@@ -1265,10 +1306,15 @@ int adxl372_probe(struct device *dev, struct regmap *regmap,
 
 	indio_dev->channels = adxl372_channels;
 	indio_dev->num_channels = ARRAY_SIZE(adxl372_channels);
-	indio_dev->available_scan_masks = adxl372_channel_masks;
 	indio_dev->name = chip_info->name;
 	indio_dev->info = &adxl372_info;
-	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+
+	if (chip_info->fifo_supported) {
+		indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
+		indio_dev->available_scan_masks = adxl372_channel_masks;
+	} else {
+		indio_dev->modes = INDIO_DIRECT_MODE;
+	}
 
 	ret = adxl372_setup(st);
 	if (ret < 0) {
@@ -1276,14 +1322,17 @@ int adxl372_probe(struct device *dev, struct regmap *regmap,
 		return ret;
 	}
 
-	ret = adxl372_buffer_setup(indio_dev);
-	if (ret < 0)
-		return ret;
+	if (chip_info->fifo_supported) {
+		ret = adxl372_buffer_setup(indio_dev);
+		if (ret < 0)
+			return ret;
+	}
 
 	return devm_iio_device_register(dev, indio_dev);
 }
 EXPORT_SYMBOL_NS_GPL(adxl372_probe, "IIO_ADXL372");
 
 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
-MODULE_DESCRIPTION("Analog Devices ADXL372 3-axis accelerometer driver");
+MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com>");
+MODULE_DESCRIPTION("Analog Devices ADXL371/ADXL372 3-axis accelerometer driver");
 MODULE_LICENSE("GPL");
diff --git a/drivers/iio/accel/adxl372.h b/drivers/iio/accel/adxl372.h
index 3ce06609446c..353a8b3a9d76 100644
--- a/drivers/iio/accel/adxl372.h
+++ b/drivers/iio/accel/adxl372.h
@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0+ */
 /*
- * ADXL372 3-Axis Digital Accelerometer
+ * ADXL371/ADXL372 3-Axis Digital Accelerometer
  *
  * Copyright 2018 Analog Devices Inc.
  */
@@ -20,8 +20,10 @@ struct adxl372_chip_info {
 	unsigned int inact_time_scale_ms;
 	unsigned int inact_time_scale_low_ms;
 	unsigned int max_odr;
+	bool fifo_supported;
 };
 
+extern const struct adxl372_chip_info adxl371_chip_info;
 extern const struct adxl372_chip_info adxl372_chip_info;
 
 int adxl372_probe(struct device *dev, struct regmap *regmap,
diff --git a/drivers/iio/accel/adxl372_i2c.c b/drivers/iio/accel/adxl372_i2c.c
index 3f97126a87a1..40acfa611c83 100644
--- a/drivers/iio/accel/adxl372_i2c.c
+++ b/drivers/iio/accel/adxl372_i2c.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * ADXL372 3-Axis Digital Accelerometer I2C driver
+ * ADXL371/ADXL372 3-Axis Digital Accelerometer I2C driver
  *
  * Copyright 2018 Analog Devices Inc.
  */
@@ -46,12 +46,14 @@ static int adxl372_i2c_probe(struct i2c_client *client)
 }
 
 static const struct i2c_device_id adxl372_i2c_id[] = {
+	{ "adxl371", (kernel_ulong_t)&adxl371_chip_info },
 	{ "adxl372", (kernel_ulong_t)&adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adxl372_i2c_id);
 
 static const struct of_device_id adxl372_of_match[] = {
+	{ .compatible = "adi,adxl371", .data = &adxl371_chip_info },
 	{ .compatible = "adi,adxl372", .data = &adxl372_chip_info },
 	{ }
 };
@@ -69,6 +71,7 @@ static struct i2c_driver adxl372_i2c_driver = {
 module_i2c_driver(adxl372_i2c_driver);
 
 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
-MODULE_DESCRIPTION("Analog Devices ADXL372 3-axis accelerometer I2C driver");
+MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com>");
+MODULE_DESCRIPTION("Analog Devices ADXL371/ADXL372 3-axis accelerometer I2C driver");
 MODULE_LICENSE("GPL");
 MODULE_IMPORT_NS("IIO_ADXL372");
diff --git a/drivers/iio/accel/adxl372_spi.c b/drivers/iio/accel/adxl372_spi.c
index 0e199feb405e..438e2bef5b77 100644
--- a/drivers/iio/accel/adxl372_spi.c
+++ b/drivers/iio/accel/adxl372_spi.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * ADXL372 3-Axis Digital Accelerometer SPI driver
+ * ADXL371/ADXL372 3-Axis Digital Accelerometer SPI driver
  *
  * Copyright 2018 Analog Devices Inc.
  */
@@ -37,12 +37,14 @@ static int adxl372_spi_probe(struct spi_device *spi)
 }
 
 static const struct spi_device_id adxl372_spi_id[] = {
+	{ "adxl371", (kernel_ulong_t)&adxl371_chip_info },
 	{ "adxl372", (kernel_ulong_t)&adxl372_chip_info },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, adxl372_spi_id);
 
 static const struct of_device_id adxl372_of_match[] = {
+	{ .compatible = "adi,adxl371", .data = &adxl371_chip_info },
 	{ .compatible = "adi,adxl372", .data = &adxl372_chip_info },
 	{ }
 };
@@ -60,6 +62,7 @@ static struct spi_driver adxl372_spi_driver = {
 module_spi_driver(adxl372_spi_driver);
 
 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
-MODULE_DESCRIPTION("Analog Devices ADXL372 3-axis accelerometer SPI driver");
+MODULE_AUTHOR("Antoniu Miclaus <antoniu.miclaus@analog.com>");
+MODULE_DESCRIPTION("Analog Devices ADXL371/ADXL372 3-axis accelerometer SPI driver");
 MODULE_LICENSE("GPL");
 MODULE_IMPORT_NS("IIO_ADXL372");
-- 
2.43.0

Re: [PATCH v3 1/4] iio: accel: adxl372: introduce chip_info structure

[Andy Shevchenko]

On Fri, Mar 13, 2026 at 01:54:54PM +0200, Antoniu Miclaus wrote:
> Introduce a chip_info structure to parameterize device-specific
> properties such as ODR/bandwidth frequency tables, activity/inactivity
> timer scale factors, and the maximum ODR value. This refactors the
> driver to use chip_info lookups instead of hardcoded values, preparing
> the driver to support multiple device variants.
> 
> The sampling_frequency and filter_low_pass_3db_frequency available
> attributes are switched from custom sysfs callbacks to read_avail()
> based handling via info_mask_shared_by_type_available. This enforces
> consistent formatting through the IIO framework and makes the values
> accessible to in-kernel consumers.
> 
> The SPI/I2C probe functions are updated to pass a chip_info pointer
> instead of a device name string.
> 
> No functional change intended.

...

> enum adxl372_odr {

>  	ADXL372_ODR_1600HZ,
>  	ADXL372_ODR_3200HZ,
>  	ADXL372_ODR_6400HZ,
> +	ADXL372_ODR_NUM,

No comma for the terminator entry.

>  };

...

> static const struct iio_event_spec adxl372_events[] = {

>  	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
>  				    BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
>  		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),	\

Consider at some point making the above consistent by style with the below

	.info_mask_shared_by_type =
		BIT(IIO_CHAN_INFO_SCALE) |				\
		BIT(IIO_CHAN_INFO_SAMP_FREQ) |				\
		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),	\

> +	.info_mask_shared_by_type_available =				\
> +		BIT(IIO_CHAN_INFO_SAMP_FREQ) |				\
> +		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),	\
>  	.scan_index = index,						\

>  };

...

> +	chip_info = i2c_get_match_data(client);

> +	if (!chip_info)
> +		return -ENODEV;

It is an agreement to avoid adding a dead code such as above check.

...

> +	chip_info = spi_get_device_match_data(spi);
> +	if (!chip_info)
> +		return -ENODEV;

Ditto.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 3/4] iio: accel: adxl372: factor out buffer and trigger setup

[Andy Shevchenko]

On Fri, Mar 13, 2026 at 01:54:56PM +0200, Antoniu Miclaus wrote:
> Extract the triggered buffer, trigger allocation, and IRQ request
> logic from adxl372_probe() into a dedicated adxl372_buffer_setup()
> helper. This reduces the probe function complexity and prepares for
> conditionally disabling buffer support on device variants with
> known FIFO issues.
> 
> No functional change intended.

...

> +	ret = devm_iio_trigger_register(dev, st->dready_trig);
> +	if (ret < 0)

Consider dropping ' < 0' parts where they are not required.

> +		return ret;
> +
> +	ret = devm_iio_trigger_register(dev, st->peak_datardy_trig);
> +	if (ret < 0)
> +		return ret;
> +
> +	indio_dev->trig = iio_trigger_get(st->dready_trig);

> +	return devm_request_irq(dev, st->irq,
> +				iio_trigger_generic_data_rdy_poll,
> +				IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
> +				indio_dev->name, st->dready_trig);

This left for the context as the last one doesn't have such a check.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v3 4/4] iio: accel: adxl372: add support for ADXL371

[Andy Shevchenko]

On Fri, Mar 13, 2026 at 01:54:57PM +0200, Antoniu Miclaus wrote:
> Add support for the Analog Devices ADXL371, a +-200g 3-axis MEMS
> accelerometer sharing the same register map as the ADXL372 but with
> different ODR values (320/640/1280/2560/5120 Hz vs 400/800/1600/3200/
> 6400 Hz), different bandwidth values, and different timer scale
> factors for activity/inactivity detection.
> 
> Due to a silicon anomaly (er001) causing FIFO data misalignment on
> all current ADXL371 silicon, FIFO and triggered buffer support is
> disabled for the ADXL371 - only direct mode reads are supported.

...

> +enum adxl371_odr {
> +	ADXL371_ODR_320HZ,
> +	ADXL371_ODR_640HZ,
> +	ADXL371_ODR_1280HZ,
> +	ADXL371_ODR_2560HZ,
> +	ADXL371_ODR_5120HZ,
> +	ADXL371_ODR_NUM,

No comma for the terminator entry.

> +};

...

> @@ -1217,8 +1258,8 @@ static int adxl372_buffer_setup(struct iio_dev *indio_dev)
>  		return -ENOMEM;
>  
>  	st->peak_datardy_trig = devm_iio_trigger_alloc(dev, "%s-dev%d-peak",
> -							indio_dev->name,
> -							iio_device_id(indio_dev));
> +						       indio_dev->name,
> +						       iio_device_id(indio_dev));
>  	if (!st->peak_datardy_trig)
>  		return -ENOMEM;

Stray change. It doesn't belong to this patch.

-- 
With Best Regards,
Andy Shevchenko