[PATCH 2/2] iio: accel: Add driver support for ADXL355

From: Puranjay Mohan
Date: Sun Jul 18 2021 - 14:00:41 EST

ADXL355 is 3-axis MEMS Accelerometer. It offers low noise density,
low 0g offset drift, low power with selectable measurement ranges.
It also features programmable high-pass and low-pass filters.

Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adxl354_adxl355.pdf
Signed-off-by: Puranjay Mohan <puranjay12@xxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/iio/accel/Kconfig | 29 ++
drivers/iio/accel/Makefile | 3 +
drivers/iio/accel/adxl355.h | 83 +++++
drivers/iio/accel/adxl355_core.c | 544 +++++++++++++++++++++++++++++++
drivers/iio/accel/adxl355_i2c.c | 63 ++++
drivers/iio/accel/adxl355_spi.c | 66 ++++
7 files changed, 795 insertions(+)
create mode 100644 drivers/iio/accel/adxl355.h
create mode 100644 drivers/iio/accel/adxl355_core.c
create mode 100644 drivers/iio/accel/adxl355_i2c.c
create mode 100644 drivers/iio/accel/adxl355_spi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index bd7aff0c1..461f2a192 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -586,6 +586,13 @@ W: http://ez.analog.com/community/linux-device-drivers
F: Documentation/devicetree/bindings/iio/accel/adi,adxl345.yaml
F: drivers/input/misc/adxl34x.c

+ADXL355 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
+M: Puranjay Mohan <puranjay12@xxxxxxxxx>
+L: linux-iio@xxxxxxxxxxxxxxx
+S: Supported
+F: drivers/iio/accel/adxl34x.c
+F: Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml
+
ADXL372 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
M: Michael Hennerich <michael.hennerich@xxxxxxxxxx>
S: Supported
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index cceda3cec..9a65353a4 100644
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -61,6 +61,35 @@ config ADXL345_SPI
will be called adxl345_spi and you will also get adxl345_core
for the core module.

+config ADXL355
+ tristate
+
+config ADXL355_I2C
+ tristate "Analog Devices ADXL355 3-Axis Digital Accelerometer I2C Driver"
+ depends on I2C
+ select ADXL355
+ select REGMAP_I2C
+ help
+ Say Y here if you want to build support for the Analog Devices
+ ADXL355 3-axis digital accelerometer.
+
+ To compile this driver as a module, choose M here: the module
+ will be called adxl355_i2c and you will also get adxl355_core
+ for the core module.
+
+config ADXL355_SPI
+ tristate "Analog Devices ADXL355 3-Axis Digital Accelerometer SPI Driver"
+ depends on SPI
+ select ADXL355
+ select REGMAP_SPI
+ help
+ Say Y here if you want to build support for the Analog Devices
+ ADXL355 3-axis digital accelerometer.
+
+ To compile this driver as a module, choose M here: the module
+ will be called adxl355_spi and you will also get adxl355_core
+ for the core module.
+
config ADXL372
tristate
select IIO_BUFFER
diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index 32cd1342a..0e4721d2d 100644
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -9,6 +9,9 @@ obj-$(CONFIG_ADIS16209) += adis16209.o
obj-$(CONFIG_ADXL345) += adxl345_core.o
obj-$(CONFIG_ADXL345_I2C) += adxl345_i2c.o
obj-$(CONFIG_ADXL345_SPI) += adxl345_spi.o
+obj-$(CONFIG_ADXL355) += adxl355_core.o
+obj-$(CONFIG_ADXL355_I2C) += adxl355_i2c.o
+obj-$(CONFIG_ADXL355_SPI) += adxl355_spi.o
obj-$(CONFIG_ADXL372) += adxl372.o
obj-$(CONFIG_ADXL372_I2C) += adxl372_i2c.o
obj-$(CONFIG_ADXL372_SPI) += adxl372_spi.o
diff --git a/drivers/iio/accel/adxl355.h b/drivers/iio/accel/adxl355.h
new file mode 100644
index 000000000..e52c294d8
--- /dev/null
+++ b/drivers/iio/accel/adxl355.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ADXL355 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Puranjay Mohan <puranjay12@xxxxxxxxx>
+ */
+
+#ifndef _ADXL355_H_
+#define _ADXL355_H_
+
+#include <linux/regmap.h>
+
+/* ADXL355 Register Definitions */
+#define ADXL355_DEVID_AD 0x00
+#define ADXL355_DEVID_MST 0x01
+#define ADXL355_PARTID 0x02
+#define ADXL355_REVID 0x03
+#define ADXL355_STATUS 0x04
+#define ADXL355_FIFO_ENTRIES 0x05
+#define ADXL355_TEMP2 0x06
+#define ADXL355_XDATA3 0x08
+#define ADXL355_YDATA3 0x0B
+#define ADXL355_ZDATA3 0x0E
+#define ADXL355_FIFO_DATA 0x11
+#define ADXL355_OFFSET_X_H 0x1E
+#define ADXL355_OFFSET_Y_H 0x20
+#define ADXL355_OFFSET_Z_H 0x22
+#define ADXL355_ACT_EN 0x24
+#define ADXL355_ACT_THRESH_H 0x25
+#define ADXL355_ACT_THRESH_L 0x26
+#define ADXL355_ACT_COUNT 0x27
+#define ADXL355_FILTER 0x28
+#define ADXL355_FIFO_SAMPLES 0x29
+#define ADXL355_INT_MAP 0x2A
+#define ADXL355_SYNC 0x2B
+#define ADXL355_RANGE 0x2C
+#define ADXL355_POWER_CTL 0x2D
+#define ADXL355_SELF_TEST 0x2E
+#define ADXL355_RESET 0x2F
+
+#define ADXL355_DEVID_AD_VAL 0xAD
+#define ADXL355_DEVID_MST_VAL 0x1D
+#define ADXL355_PARTID_VAL 0xED
+#define ADXL355_REVID_VAL 0x01
+#define ADXL355_RESET_CODE 0x52
+
+#define ADXL355_POWER_CTL_MODE_MSK GENMASK(1, 0)
+
+#define ADXL355_FILTER_ODR_MSK GENMASK(3, 0)
+#define ADXL355_FILTER_ODR_MODE(x) ((x) & 0xF)
+#define ADXL355_FILTER_HPF_MSK GENMASK(6, 4)
+#define ADXL355_FILTER_HPF_MODE(x) (((x) & 0x7) << 4)
+
+/*
+ * The datasheet defines an intercept of 1885 LSB at 25 degC
+ * and a slope of -9.05 LSB/C. The following formula can be used to find the
+ * temperature:
+ * Temp = ((RAW - 1885)/(-9.05)) + 25 but this doesn't follow the format of
+ * the IIO which is Temp = (RAW + OFFSET) * SCALE. Hence using some rearranging
+ * we get the scale as -110.49723 and offset as -2111.25
+ */
+#define TEMP_SCALE_VAL -110
+#define TEMP_SCALE_VAL2 497238
+#define TEMP_OFFSET_VAL -2111
+#define TEMP_OFFSET_VAL2 250000
+
+/*
+ * At +/- 2g with 20-bit resolution, scale is given in datasheet as
+ * 3.9ug/LSB = 0.0000039 * 9.80665 = 0.00003824593 m/s^2
+ */
+#define ADXL355_NSCALE 38245
+
+extern const struct regmap_range adxl355_read_reg_range[];
+
+extern const struct regmap_access_table adxl355_readable_regs_tbl;
+
+extern const struct regmap_range adxl355_write_reg_range[];
+
+extern const struct regmap_access_table adxl355_writeable_regs_tbl;
+
+int adxl355_core_probe(struct device *dev, struct regmap *regmap,
+ const char *name);
+#endif /* _ADXL355_H_ */
diff --git a/drivers/iio/accel/adxl355_core.c b/drivers/iio/accel/adxl355_core.c
new file mode 100644
index 000000000..5fdd3c73e
--- /dev/null
+++ b/drivers/iio/accel/adxl355_core.c
@@ -0,0 +1,544 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer IIO core driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <puranjay12@xxxxxxxxx>
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adxl354_adxl355.pdf
+ */
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/limits.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "adxl355.h"
+
+const struct regmap_range adxl355_read_reg_range[] = {
+ regmap_reg_range(ADXL355_DEVID_AD, ADXL355_FIFO_DATA),
+ regmap_reg_range(ADXL355_OFFSET_X_H, ADXL355_SELF_TEST)
+};
+EXPORT_SYMBOL_GPL(adxl355_read_reg_range);
+
+const struct regmap_access_table adxl355_readable_regs_tbl = {
+ .yes_ranges = adxl355_read_reg_range,
+ .n_yes_ranges = ARRAY_SIZE(adxl355_read_reg_range),
+};
+EXPORT_SYMBOL_GPL(adxl355_readable_regs_tbl);
+
+const struct regmap_range adxl355_write_reg_range[] = {
+ regmap_reg_range(ADXL355_OFFSET_X_H, ADXL355_RESET)
+};
+EXPORT_SYMBOL_GPL(adxl355_write_reg_range);
+
+const struct regmap_access_table adxl355_writeable_regs_tbl = {
+ .yes_ranges = adxl355_write_reg_range,
+ .n_yes_ranges = ARRAY_SIZE(adxl355_write_reg_range),
+};
+EXPORT_SYMBOL_GPL(adxl355_writeable_regs_tbl);
+
+enum adxl355_op_mode {
+ ADXL355_MEASUREMENT,
+ ADXL355_STANDBY,
+ ADXL355_TEMP_OFF
+};
+
+enum adxl355_odr {
+ ADXL355_ODR_4000HZ,
+ ADXL355_ODR_2000HZ,
+ ADXL355_ODR_1000HZ,
+ ADXL355_ODR_500HZ,
+ ADXL355_ODR_250HZ,
+ ADXL355_ODR_125HZ,
+ ADXL355_ODR_62_5HZ,
+ ADXL355_ODR_31_25HZ,
+ ADXL355_ODR_15_625HZ,
+ ADXL355_ODR_7_813HZ,
+ ADXL355_ODR_3_906HZ
+};
+
+enum adxl355_hpf_3db {
+ ADXL355_HPF_OFF,
+ ADXL355_HPF_24_7,
+ ADXL355_HPF_6_2084,
+ ADXL355_HPF_1_5545,
+ ADXL355_HPF_0_3862,
+ ADXL355_HPF_0_0954,
+ ADXL355_HPF_0_0238
+};
+
+static const int adxl355_odr_table[][2] = {
+ [0] = {4000, 0},
+ [1] = {2000, 0},
+ [2] = {1000, 0},
+ [3] = {500, 0},
+ [4] = {250, 0},
+ [5] = {125, 0},
+ [6] = {62, 500000},
+ [7] = {31, 250000},
+ [8] = {15, 625000},
+ [9] = {7, 813000},
+ [10] = {3, 906000}
+};
+
+static int adxl355_hpf_3db_table[7][2] = {0};
+
+static const int adxl355_hpf_3db_multipliers[] = {
+ 0,
+ 247000,
+ 62084,
+ 15545,
+ 3862,
+ 954,
+ 238
+};
+
+struct adxl355_data {
+ struct regmap *regmap;
+ struct device *dev;
+ struct mutex lock; /* lock to protect op_mode */
+ enum adxl355_op_mode op_mode;
+ enum adxl355_odr odr;
+ enum adxl355_hpf_3db hpf_3db;
+ int x_calibbias;
+ int y_calibbias;
+ int z_calibbias;
+};
+
+static int adxl355_set_op_mode(struct adxl355_data *data,
+ enum adxl355_op_mode op_mode)
+{
+ int ret;
+
+ if (data->op_mode == op_mode)
+ return 0;
+
+ ret = regmap_update_bits(data->regmap, ADXL355_POWER_CTL,
+ ADXL355_POWER_CTL_MODE_MSK, op_mode);
+ if (ret < 0)
+ return ret;
+
+ data->op_mode = op_mode;
+
+ return ret;
+}
+
+static void adxl355_fill_3db_frequency_table(struct adxl355_data *data)
+{
+ int i;
+ u64 rem;
+ u64 div;
+ u32 multiplier;
+ u64 odr = mul_u64_u32_shr(adxl355_odr_table[data->odr][0], 1000000, 0) +
+ adxl355_odr_table[data->odr][1];
+
+ for (i = 0; i < ARRAY_SIZE(adxl355_hpf_3db_multipliers); i++) {
+ multiplier = adxl355_hpf_3db_multipliers[i];
+ div = div64_u64_rem(mul_u64_u32_shr(odr, multiplier, 0),
+ 100000000000000UL, &rem);
+
+ adxl355_hpf_3db_table[i][0] = div;
+ adxl355_hpf_3db_table[i][1] = div_u64(rem, 100000000);
+ }
+}
+
+static int adxl355_setup(struct adxl355_data *data)
+{
+ unsigned int regval;
+ int ret;
+
+ ret = regmap_read(data->regmap, ADXL355_DEVID_AD, &regval);
+ if (ret < 0)
+ return ret;
+
+ if (regval != ADXL355_DEVID_AD_VAL) {
+ dev_err(data->dev, "Invalid ADI ID 0x%02x\n", regval);
+ return -ENODEV;
+ }
+
+ ret = regmap_read(data->regmap, ADXL355_DEVID_MST, &regval);
+ if (ret < 0)
+ return ret;
+
+ if (regval != ADXL355_DEVID_MST_VAL) {
+ dev_err(data->dev, "Invalid MEMS ID 0x%02x\n", regval);
+ return -ENODEV;
+ }
+
+ ret = regmap_read(data->regmap, ADXL355_PARTID, &regval);
+ if (ret < 0)
+ return ret;
+
+ if (regval != ADXL355_PARTID_VAL) {
+ dev_err(data->dev, "Invalid DEV ID 0x%02x\n", regval);
+ return -ENODEV;
+ }
+
+ /*
+ * Perform a software reset to make sure the device is in a consistent
+ * state after start up.
+ */
+ ret = regmap_write(data->regmap, ADXL355_RESET, ADXL355_RESET_CODE);
+ if (ret < 0)
+ return ret;
+
+ adxl355_fill_3db_frequency_table(data);
+
+ return adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
+}
+
+static int adxl355_get_temp_data(struct adxl355_data *data,
+ u8 addr, __be16 *out)
+{
+ return regmap_bulk_read(data->regmap, addr, out, sizeof(*out));
+}
+
+static int adxl355_read_axis(struct adxl355_data *data, u8 addr)
+{
+ __be32 regval;
+ int ret;
+
+ ret = regmap_bulk_read(data->regmap, addr, &regval, 3);
+ if (ret < 0)
+ return ret;
+
+ return be32_to_cpu(regval) >> 8;
+}
+
+static int adxl355_find_match(const int (*freq_tbl)[2], const int n,
+ const int val, const int val2)
+{
+ int i;
+
+ for (i = 0; i < n; i++) {
+ if (freq_tbl[i][0] == val && freq_tbl[i][1] == val2)
+ return i;
+ }
+
+ return -EINVAL;
+}
+
+static int adxl355_set_odr(struct adxl355_data *data,
+ enum adxl355_odr odr)
+{
+ int ret = 0;
+
+ mutex_lock(&data->lock);
+
+ if (data->odr == odr)
+ goto out_unlock;
+
+ ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
+ if (ret < 0)
+ goto out_unlock;
+
+ ret = regmap_update_bits(data->regmap, ADXL355_FILTER,
+ ADXL355_FILTER_ODR_MSK,
+ ADXL355_FILTER_ODR_MODE(odr));
+ if (!ret) {
+ data->odr = odr;
+ adxl355_fill_3db_frequency_table(data);
+ }
+
+out_unlock:
+ ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int adxl355_set_hpf_3db(struct adxl355_data *data,
+ enum adxl355_hpf_3db hpf)
+{
+ int ret = 0;
+
+ mutex_lock(&data->lock);
+
+ if (data->hpf_3db == hpf)
+ goto out_unlock;
+
+ ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
+ if (ret < 0)
+ goto out_unlock;
+
+ ret = regmap_update_bits(data->regmap, ADXL355_FILTER,
+ ADXL355_FILTER_HPF_MSK,
+ ADXL355_FILTER_HPF_MODE(hpf));
+ if (!ret)
+ data->hpf_3db = hpf;
+
+out_unlock:
+ ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int adxl355_set_calibbias(struct adxl355_data *data,
+ int scan_index, int calibbias)
+{
+ int ret = 0;
+ __be16 reg = cpu_to_be16(calibbias);
+
+ mutex_lock(&data->lock);
+
+ ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
+ if (ret < 0)
+ goto out_unlock;
+
+ switch (scan_index) {
+ case 0:
+ ret = regmap_bulk_write(data->regmap, ADXL355_OFFSET_X_H,
+ &reg, 2);
+ if (ret < 0)
+ goto out_unlock;
+ data->x_calibbias = calibbias;
+ break;
+ case 1:
+ ret = regmap_bulk_write(data->regmap, ADXL355_OFFSET_Y_H,
+ &reg, 2);
+ if (ret < 0)
+ goto out_unlock;
+ data->y_calibbias = calibbias;
+ break;
+ case 2:
+ ret = regmap_bulk_write(data->regmap, ADXL355_OFFSET_Z_H,
+ &reg, 2);
+ if (ret < 0)
+ goto out_unlock;
+ data->z_calibbias = calibbias;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out_unlock:
+ ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int adxl355_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct adxl355_data *data = iio_priv(indio_dev);
+ int ret;
+ __be16 out;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_TEMP:
+ ret = adxl355_get_temp_data(data, chan->address, &out);
+ if (ret < 0)
+ break;
+ *val = be16_to_cpu(out);
+ ret = IIO_VAL_INT;
+ break;
+
+ case IIO_ACCEL:
+ ret = adxl355_read_axis(data, chan->address);
+ if (ret < 0)
+ break;
+ *val = sign_extend32(ret >> (chan->scan_type.shift),
+ chan->scan_type.realbits - 1);
+ ret = IIO_VAL_INT;
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ return ret;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_TEMP:
+ *val = TEMP_SCALE_VAL;
+ *val2 = TEMP_SCALE_VAL2;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_ACCEL:
+ *val = 0;
+ *val2 = ADXL355_NSCALE;
+ return IIO_VAL_INT_PLUS_NANO;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_OFFSET:
+ *val = TEMP_OFFSET_VAL;
+ *val2 = TEMP_OFFSET_VAL2;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ if (chan->scan_index == 0)
+ *val = data->x_calibbias;
+ else if (chan->scan_index == 1)
+ *val = data->y_calibbias;
+ else
+ *val = data->z_calibbias;
+ *val = sign_extend32(*val, 15);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = adxl355_odr_table[data->odr][0];
+ *val2 = adxl355_odr_table[data->odr][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+ *val = adxl355_hpf_3db_table[data->hpf_3db][0];
+ *val2 = adxl355_hpf_3db_table[data->hpf_3db][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ return -EINVAL;
+}
+
+static int adxl355_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct adxl355_data *data = iio_priv(indio_dev);
+ int odr_idx, hpf_idx, calibbias, ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ odr_idx = adxl355_find_match(adxl355_odr_table,
+ ARRAY_SIZE(adxl355_odr_table),
+ val, val2);
+ if (odr_idx < 0)
+ return odr_idx;
+
+ return adxl355_set_odr(data, odr_idx);
+ case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+ hpf_idx = adxl355_find_match(adxl355_hpf_3db_table,
+ ARRAY_SIZE(adxl355_hpf_3db_table),
+ val, val2);
+ if (hpf_idx < 0)
+ return hpf_idx;
+
+ return adxl355_set_hpf_3db(data, hpf_idx);
+ case IIO_CHAN_INFO_CALIBBIAS:
+ calibbias = clamp_t(int, val, S16_MIN, S16_MAX);
+ ret = adxl355_set_calibbias(data, chan->scan_index, calibbias);
+
+ return ret;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int adxl355_read_avail(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ const int **vals, int *type, int *length,
+ long mask)
+{
+ switch (mask) {
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *vals = (const int *)adxl355_odr_table;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ /* Values are stored in a 2D matrix */
+ *length = ARRAY_SIZE(adxl355_odr_table) * 2;
+
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
+ *vals = (const int *)adxl355_hpf_3db_table;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ /* Values are stored in a 2D matrix */
+ *length = ARRAY_SIZE(adxl355_hpf_3db_table) * 2;
+
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const unsigned long adxl355_avail_scan_masks[] = {
+ GENMASK(3, 0),
+ 0
+};
+
+static const struct iio_info adxl355_info = {
+ .read_raw = adxl355_read_raw,
+ .write_raw = adxl355_write_raw,
+ .read_avail = &adxl355_read_avail
+};
+
+#define ADXL355_ACCEL_CHANNEL(index, reg, axis) { \
+ .type = IIO_ACCEL, \
+ .address = reg, \
+ .modified = 1, \
+ .channel2 = IIO_MOD_##axis, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
+ BIT(IIO_CHAN_INFO_CALIBBIAS), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+ BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
+ .info_mask_shared_by_type_available = \
+ BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
+ BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 20, \
+ .storagebits = 32, \
+ .shift = 4, \
+ .endianness = IIO_BE, \
+ } \
+}
+
+static const struct iio_chan_spec adxl355_channels[] = {
+ ADXL355_ACCEL_CHANNEL(0, ADXL355_XDATA3, X),
+ ADXL355_ACCEL_CHANNEL(1, ADXL355_YDATA3, Y),
+ ADXL355_ACCEL_CHANNEL(2, ADXL355_ZDATA3, Z),
+ {
+ .type = IIO_TEMP,
+ .address = ADXL355_TEMP2,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .scan_index = 3,
+ .scan_type = {
+ .sign = 's',
+ .realbits = 12,
+ .storagebits = 16,
+ .endianness = IIO_BE,
+ },
+ }
+};
+
+int adxl355_core_probe(struct device *dev, struct regmap *regmap,
+ const char *name)
+{
+ struct adxl355_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ data = iio_priv(indio_dev);
+ data->regmap = regmap;
+ data->dev = dev;
+ data->op_mode = ADXL355_STANDBY;
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = dev;
+ indio_dev->name = name;
+ indio_dev->info = &adxl355_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = adxl355_channels;
+ indio_dev->num_channels = ARRAY_SIZE(adxl355_channels);
+ indio_dev->available_scan_masks = adxl355_avail_scan_masks;
+
+ ret = adxl355_setup(data);
+ if (ret < 0) {
+ dev_err(dev, "ADXL355 setup failed\n");
+ return ret;
+ }
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+EXPORT_SYMBOL_GPL(adxl355_core_probe);
+
+MODULE_AUTHOR("Puranjay Mohan <puranjay12@xxxxxxxxx>");
+MODULE_DESCRIPTION("ADXL355 3-Axis Digital Accelerometer core driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/adxl355_i2c.c b/drivers/iio/accel/adxl355_i2c.c
new file mode 100644
index 000000000..1c9764129
--- /dev/null
+++ b/drivers/iio/accel/adxl355_i2c.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer I2C driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <puranjay12@xxxxxxxxx>
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+#include "adxl355.h"
+
+static const struct regmap_config adxl355_i2c_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0x2F,
+ .rd_table = &adxl355_readable_regs_tbl,
+ .wr_table = &adxl355_writeable_regs_tbl
+};
+
+static int adxl355_i2c_probe(struct i2c_client *client)
+{
+ struct regmap *regmap;
+
+ regmap = devm_regmap_init_i2c(client, &adxl355_i2c_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "Error initializing i2c regmap: %ld\n",
+ PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ return adxl355_core_probe(&client->dev, regmap, client->name);
+}
+
+static const struct i2c_device_id adxl355_i2c_id[] = {
+ { "adxl355", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(i2c, adxl355_i2c_id);
+
+static const struct of_device_id adxl355_of_match[] = {
+ { .compatible = "adi,adxl355" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, adxl355_of_match);
+
+static struct i2c_driver adxl355_i2c_driver = {
+ .driver = {
+ .name = "adxl355_i2c",
+ .of_match_table = adxl355_of_match,
+ },
+ .probe_new = adxl355_i2c_probe,
+ .id_table = adxl355_i2c_id,
+};
+
+module_i2c_driver(adxl355_i2c_driver);
+
+MODULE_AUTHOR("Puranjay Mohan <puranjay12@xxxxxxxxx>");
+MODULE_DESCRIPTION("ADXL355 3-Axis Digital Accelerometer I2C driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/accel/adxl355_spi.c b/drivers/iio/accel/adxl355_spi.c
new file mode 100644
index 000000000..ae02cbfad
--- /dev/null
+++ b/drivers/iio/accel/adxl355_spi.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer SPI driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <puranjay12@xxxxxxxxx>
+ */
+
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+#include "adxl355.h"
+
+static const struct regmap_config adxl355_spi_regmap_config = {
+ .reg_bits = 7,
+ .pad_bits = 1,
+ .val_bits = 8,
+ .read_flag_mask = BIT(0),
+ .max_register = 0x2F,
+ .rd_table = &adxl355_readable_regs_tbl,
+ .wr_table = &adxl355_writeable_regs_tbl
+};
+
+static int adxl355_spi_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ struct regmap *regmap;
+
+ regmap = devm_regmap_init_spi(spi, &adxl355_spi_regmap_config);
+ if (IS_ERR(regmap)) {
+ dev_err(&spi->dev, "Error initializing spi regmap: %ld\n",
+ PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ return adxl355_core_probe(&spi->dev, regmap, id->name);
+}
+
+static const struct spi_device_id adxl355_spi_id[] = {
+ { "adxl355", 0 },
+ { }
+};
+
+MODULE_DEVICE_TABLE(spi, adxl355_spi_id);
+
+static const struct of_device_id adxl355_of_match[] = {
+ { .compatible = "adi,adxl355" },
+ { },
+};
+
+MODULE_DEVICE_TABLE(of, adxl355_of_match);
+
+static struct spi_driver adxl355_spi_driver = {
+ .driver = {
+ .name = "adxl355_spi",
+ .of_match_table = adxl355_of_match,
+ },
+ .probe = adxl355_spi_probe,
+ .id_table = adxl355_spi_id,
+};
+
+module_spi_driver(adxl355_spi_driver);
+
+MODULE_AUTHOR("Puranjay Mohan <puranjay12@xxxxxxxxx>");
+MODULE_DESCRIPTION("ADXL355 3-Axis Digital Accelerometer SPI driver");
+MODULE_LICENSE("GPL v2");
--
2.30.1