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 v4:
 - Drop trailing comma from ADXL371_ODR_NUM enum terminator.

 drivers/iio/accel/Kconfig       | 12 +++----
 drivers/iio/accel/adxl372.c     | 63 +++++++++++++++++++++++++++++----
 drivers/iio/accel/adxl372.h     |  4 ++-
 drivers/iio/accel/adxl372_i2c.c |  7 ++--
 drivers/iio/accel/adxl372_spi.c |  7 ++--
 5 files changed, 75 insertions(+), 18 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 6fd4fe0ec1d9..478ae68f0553 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");
 
@@ -1266,10 +1307,15 @@ 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) {
@@ -1277,14 +1323,17 @@ 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 5d135b1150c8..ca2cabf24938 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.
  */
@@ -44,12 +44,14 @@ 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 },
 	{ }
 };
@@ -67,6 +69,7 @@ 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 e96a355bfe67..1f9c1544e547 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.
  */
@@ -35,12 +35,14 @@ 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 },
 	{ }
 };
@@ -58,6 +60,7 @@ 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