[PATCH 0/3] iio: accel: adxl372: add ADXL371 support

[PATCH 0/3] iio: accel: adxl372: add ADXL371 support

[Antoniu Miclaus]

Add support for the Analog Devices ADXL371, a +-200g 3-axis MEMS
accelerometer that shares the same register map as the ADXL372 but
differs in ODR/bandwidth values (320-5120 Hz vs 400-6400 Hz) and
timer scale factors.

The first patch introduces a chip_info structure to parameterize
device-specific properties, replacing hardcoded values with per-chip
lookups. The second patch adds the ADXL371 compatible string to the
dt-binding. The third patch adds the ADXL371 chip_info and disables
FIFO support due to a silicon anomaly (er001) that causes FIFO data
misalignment on all current ADXL371 silicon.

Antoniu Miclaus (3):
  iio: accel: adxl372: introduce chip_info structure
  dt-bindings: iio: accel: adi,adxl372: add ADXL371 compatible
  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                   | 220 ++++++++++++------
 drivers/iio/accel/adxl372.h                   |  20 +-
 drivers/iio/accel/adxl372_i2c.c               |  19 +-
 drivers/iio/accel/adxl372_spi.c               |  19 +-
 7 files changed, 205 insertions(+), 99 deletions(-)

-- 
2.43.0

[PATCH 1/3] 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_available sysfs attribute is changed from a
static const string to a dynamic callback that reads from chip_info,
and 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>
---
 drivers/iio/accel/adxl372.c     | 94 ++++++++++++++++++++++-----------
 drivers/iio/accel/adxl372.h     | 16 +++++-
 drivers/iio/accel/adxl372_i2c.c | 12 +++--
 drivers/iio/accel/adxl372_spi.c | 12 +++--
 4 files changed, 93 insertions(+), 41 deletions(-)

diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
index 28a8793a53b6..d1f957adea64 100644
--- a/drivers/iio/accel/adxl372.c
+++ b/drivers/iio/accel/adxl372.c
@@ -222,6 +222,19 @@ static const int adxl372_bw_freq_tbl[5] = {
 	200, 400, 800, 1600, 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;
@@ -279,6 +292,7 @@ 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 +485,14 @@ 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 +516,14 @@ 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 +733,7 @@ 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 +793,10 @@ 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 +812,17 @@ 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 +835,9 @@ 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;
@@ -968,7 +978,7 @@ static ssize_t adxl372_show_filter_freq_avail(struct device *dev,
 
 	for (i = 0; i <= st->odr; i++)
 		len += scnprintf(buf + len, PAGE_SIZE - len,
-				 "%d ", adxl372_bw_freq_tbl[i]);
+				 "%d ", st->chip_info->bw_freq_tbl[i]);
 
 	buf[len - 1] = '\n';
 
@@ -1142,12 +1152,31 @@ 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 ssize_t adxl372_show_samp_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->chip_info->num_freqs; i++)
+		len += scnprintf(buf + len, PAGE_SIZE - len,
+				 "%d ", st->chip_info->samp_freq_tbl[i]);
+
+	buf[len - 1] = '\n';
+
+	return len;
+}
+
+static IIO_DEVICE_ATTR(sampling_frequency_available,
+		       0444, adxl372_show_samp_freq_avail, NULL, 0);
 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_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,
 	NULL,
 };
@@ -1176,7 +1205,7 @@ 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 +1221,14 @@ 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 2/3] 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.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
---
 .../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 3/3] 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>
---
 drivers/iio/accel/Kconfig       |  12 +--
 drivers/iio/accel/adxl372.c     | 126 +++++++++++++++++++++-----------
 drivers/iio/accel/adxl372.h     |   4 +-
 drivers/iio/accel/adxl372_i2c.c |   7 +-
 drivers/iio/accel/adxl372_spi.c |   7 +-
 5 files changed, 102 insertions(+), 54 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 d1f957adea64..10eb5bf14dad 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.
  */
@@ -182,6 +182,14 @@ enum adxl372_odr {
 	ADXL372_ODR_6400HZ,
 };
 
+enum adxl371_odr {
+	ADXL371_ODR_320HZ,
+	ADXL371_ODR_640HZ,
+	ADXL371_ODR_1280HZ,
+	ADXL371_ODR_2560HZ,
+	ADXL371_ODR_5120HZ,
+};
+
 enum adxl372_bandwidth {
 	ADXL372_BW_200HZ,
 	ADXL372_BW_400HZ,
@@ -222,6 +230,29 @@ static const int adxl372_bw_freq_tbl[5] = {
 	200, 400, 800, 1600, 3200,
 };
 
+static const int adxl371_samp_freq_tbl[5] = {
+	320, 640, 1280, 2560, 5120,
+};
+
+static const int adxl371_bw_freq_tbl[5] = {
+	160, 320, 640, 1280, 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,
@@ -232,6 +263,7 @@ 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");
 
@@ -1227,10 +1259,15 @@ 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) {
@@ -1238,50 +1275,52 @@ 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);
-	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 (chip_info->fifo_supported) {
+		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;
 
-		ret = devm_iio_trigger_register(dev, st->peak_datardy_trig);
-		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)
+				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);
+			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;
+			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);
@@ -1289,5 +1328,6 @@ int adxl372_probe(struct device *dev, struct regmap *regmap,
 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 1/3] iio: accel: adxl372: introduce chip_info structure

[Andy Shevchenko]

On Mon, Mar 02, 2026 at 02:20:57PM +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_available sysfs attribute is changed from a
> static const string to a dynamic callback that reads from chip_info,
> and the SPI/I2C probe functions are updated to pass a chip_info
> pointer instead of a device name string.
> 
> No functional change intended.

...

> -static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("400 800 1600 3200 6400");
> +static ssize_t adxl372_show_samp_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->chip_info->num_freqs; i++)

> +		len += scnprintf(buf + len, PAGE_SIZE - len,
> +				 "%d ", st->chip_info->samp_freq_tbl[i]);

This is part of sysfs, use sysfs_emit_at().

> +	buf[len - 1] = '\n';
> +
> +	return len;
> +}
> +
> +static IIO_DEVICE_ATTR(sampling_frequency_available,
> +		       0444, adxl372_show_samp_freq_avail, NULL, 0);

What's wrong with IIO_DEVICE_ATTR_RO()?

>  static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available,
>  		       0444, adxl372_show_filter_freq_avail, NULL, 0);

Make sure this is closer to its callback(s).

...

>  static struct attribute *adxl372_attributes[] = {
> -	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
> +	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
>  	&iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,

>  	NULL,

Side note: At some point consider dropping trailing comma in the terminator.

>  };

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH 2/3] dt-bindings: iio: accel: adi,adxl372: add ADXL371 compatible

[Conor Dooley]

[-- Attachment #1: Type: text/plain, Size: 75 bytes --]

Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH 1/3] iio: accel: adxl372: introduce chip_info structure

[Jonathan Cameron]

On Mon, 2 Mar 2026 14:59:37 +0200
Andy Shevchenko <andriy.shevchenko@intel.com> wrote:

> On Mon, Mar 02, 2026 at 02:20:57PM +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_available sysfs attribute is changed from a
> > static const string to a dynamic callback that reads from chip_info,
> > and the SPI/I2C probe functions are updated to pass a chip_info
> > pointer instead of a device name string.
> > 
> > No functional change intended.  
> 
> ...
> 
> > -static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("400 800 1600 3200 6400");
> > +static ssize_t adxl372_show_samp_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->chip_info->num_freqs; i++)  
> 
> > +		len += scnprintf(buf + len, PAGE_SIZE - len,
> > +				 "%d ", st->chip_info->samp_freq_tbl[i]);  
> 
> This is part of sysfs, use sysfs_emit_at().

Instead can we switch this to read_avail() based handling?
That means setting info_mask_shared_by_all_available
bit for sampling frequency.

Looks superficially easy to do the same for the
filter_low_pass_3db_frequency_available.

The attributes go away entirely.
Advantage of this is it both enforces the formatting without us having
to read the functions carefully and it makes them available to in kernel
consumers.

Jonathan



> 
> > +	buf[len - 1] = '\n';
> > +
> > +	return len;
> > +}
> > +
> > +static IIO_DEVICE_ATTR(sampling_frequency_available,
> > +		       0444, adxl372_show_samp_freq_avail, NULL, 0);  
> 
> What's wrong with IIO_DEVICE_ATTR_RO()?
> 
> >  static IIO_DEVICE_ATTR(in_accel_filter_low_pass_3db_frequency_available,
> >  		       0444, adxl372_show_filter_freq_avail, NULL, 0);  
> 
> Make sure this is closer to its callback(s).
> 
> ...
> 
> >  static struct attribute *adxl372_attributes[] = {
> > -	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
> > +	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
> >  	&iio_dev_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,  
> 
> >  	NULL,  
> 
> Side note: At some point consider dropping trailing comma in the terminator.
> 
> >  };  
> 

Re: [PATCH 3/3] iio: accel: adxl372: add support for ADXL371

[Jonathan Cameron]

On Mon, 2 Mar 2026 14:20:59 +0200
Antoniu Miclaus <antoniu.miclaus@analog.com> 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.

Ouch.

> 

> diff --git a/drivers/iio/accel/adxl372.c b/drivers/iio/accel/adxl372.c
> index d1f957adea64..10eb5bf14dad 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.
>   */
> @@ -182,6 +182,14 @@ enum adxl372_odr {
>  	ADXL372_ODR_6400HZ,
>  };
>  
> +enum adxl371_odr {
> +	ADXL371_ODR_320HZ,
> +	ADXL371_ODR_640HZ,
> +	ADXL371_ODR_1280HZ,
> +	ADXL371_ODR_2560HZ,
> +	ADXL371_ODR_5120HZ,
> +};
> +
>  enum adxl372_bandwidth {
>  	ADXL372_BW_200HZ,
>  	ADXL372_BW_400HZ,
> @@ -222,6 +230,29 @@ static const int adxl372_bw_freq_tbl[5] = {
>  	200, 400, 800, 1600, 3200,
>  };
>  
> +static const int adxl371_samp_freq_tbl[5] = {
> +	320, 640, 1280, 2560, 5120,
It might be a good idea to make the association of ordering an element
explicit via
	[ADXL371_ODR_320HZ] = 320,
etc

> +};
> +
> +static const int adxl371_bw_freq_tbl[5] = {

I assume these are indexed off the odr enum. If so then
	[ADXL371_ODR_320HZ] = 160, 
etc here may make sense as well.

> +	160, 320, 640, 1280, 2560,
> +};

> +		if (st->irq) {
It might be worth factoring out this block (maybe the earlier bit as well)
as a helper function in a precursor patch.  
The indent is getting rather large for such long lines.

> +			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);
> +			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;
> +			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);