2021-08-10 18:46:57

by Puranjay Mohan

[permalink] [raw]
Subject: [PATCH v10 0/2] iio: accel: add support for ADXL355

Add the dt-bindings and the driver for ADXL355 3-axis MEMS Accelerometer.

Changes since v9:
1. Fix white space issues, remove extra lines.
2. Include bits.h and device.h
3. Add commas to non-terminal lines in structs etc.

Changes since v8:
1. Make scale and offset defines inline and remove them.
2. Change dt-binding doc to state interrupt polarity only for DRDY pin.
3. Remove triggered buffer support from this patch series.

Changes since v7:
1. Update MAINTAINERS to show all driver files.
2. Set CONFIGS for buffered support in Kconfig.

Changes since v6:
1. Use interrupt-names property in device tree document.
2. Add triggered buffer support.
3. Use a static table for offset and data registers.
4. Fix coding style issues.
5. move defines from header to c file.

Changes since v5:
1. Used get_unaligned_be24() and get_unaligned_be16() to parse
acceleration and temperature data. This solves sparse errors and also
make the code more understandable.

Changes since v4:
1. Fix errors reported by sparse.

Changes since v3:
1. Fix errors in yaml DT doc.
2. Change SPDX-License-Identifier to GPL-2.0-only OR BSD-2-Clause

Changes since v2:
1. Add separate DT binding doc in yaml.
2. Use ____cacheline_aligned buffer for regmap_bulk_read/write calls.
3. Make code consistent by using same style in switch case.
4. Use FIELD_PREP in place of custom macros.
5. Make Kconfig description more informative.

Changes since v1:
1. Remove the declarations for static regmap structures from adxl355.h.
This was missed in the v1 and caused errors.
2. Make switch case statements consistent by directly returning from
each case rather than saving the return in a variable.
3. Some coding style changes.

Changes since v0:
1. Move adxl355_hpf_3db_table to adxl355_data structure. This is done to make
sure that each device gets its own table.
2. Make local regmap definitions private to adxl355_core.c.
3. Other minor coding style changes.

Puranjay Mohan (2):
dt-bindings: iio: accel: Add DT binding doc for ADXL355
iio: accel: Add driver support for ADXL355

.../bindings/iio/accel/adi,adxl355.yaml | 88 +++
MAINTAINERS | 10 +
drivers/iio/accel/Kconfig | 29 +
drivers/iio/accel/Makefile | 3 +
drivers/iio/accel/adxl355.h | 20 +
drivers/iio/accel/adxl355_core.c | 582 ++++++++++++++++++
drivers/iio/accel/adxl355_i2c.c | 62 ++
drivers/iio/accel/adxl355_spi.c | 65 ++
8 files changed, 859 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml
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

--
2.30.1


2021-08-10 18:47:24

by Puranjay Mohan

[permalink] [raw]
Subject: [PATCH v10 2/2] iio: accel: Add driver support for ADXL355

ADXL355 is a 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 <[email protected]>
---
MAINTAINERS | 10 +
drivers/iio/accel/Kconfig | 29 ++
drivers/iio/accel/Makefile | 3 +
drivers/iio/accel/adxl355.h | 20 ++
drivers/iio/accel/adxl355_core.c | 582 +++++++++++++++++++++++++++++++
drivers/iio/accel/adxl355_i2c.c | 62 ++++
drivers/iio/accel/adxl355_spi.c | 65 ++++
7 files changed, 771 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..104d22c83 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -586,6 +586,16 @@ 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 <[email protected]>
+L: [email protected]
+S: Supported
+F: Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml
+F: drivers/iio/accel/adxl355.h
+F: drivers/iio/accel/adxl355_core.c
+F: drivers/iio/accel/adxl355_i2c.c
+F: drivers/iio/accel/adxl355_spi.c
+
ADXL372 THREE-AXIS DIGITAL ACCELEROMETER DRIVER
M: Michael Hennerich <[email protected]>
S: Supported
diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index cceda3cec..d0c45c809 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 i2c 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 spi 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..d1d5cdb74
--- /dev/null
+++ b/drivers/iio/accel/adxl355.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * ADXL355 3-Axis Digital Accelerometer
+ *
+ * Copyright (c) 2021 Puranjay Mohan <[email protected]>
+ */
+
+#ifndef _ADXL355_H_
+#define _ADXL355_H_
+
+#include <linux/device.h>
+#include <linux/regmap.h>
+
+extern const struct regmap_access_table adxl355_readable_regs_tbl;
+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..474e7ee62
--- /dev/null
+++ b/drivers/iio/accel/adxl355_core.c
@@ -0,0 +1,582 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer IIO core driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <[email protected]>
+ *
+ * Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adxl354_adxl355.pdf
+ */
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/iio/iio.h>
+#include <linux/limits.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/regmap.h>
+#include <asm/unaligned.h>
+
+#include "adxl355.h"
+
+/* ADXL355 Register Definitions */
+#define ADXL355_DEVID_AD_REG 0x00
+#define ADXL355_DEVID_MST_REG 0x01
+#define ADXL355_PARTID_REG 0x02
+#define ADXL355_STATUS_REG 0x04
+#define ADXL355_FIFO_ENTRIES_REG 0x05
+#define ADXL355_TEMP2_REG 0x06
+#define ADXL355_XDATA3_REG 0x08
+#define ADXL355_YDATA3_REG 0x0B
+#define ADXL355_ZDATA3_REG 0x0E
+#define ADXL355_FIFO_DATA_REG 0x11
+#define ADXL355_OFFSET_X_H_REG 0x1E
+#define ADXL355_OFFSET_Y_H_REG 0x20
+#define ADXL355_OFFSET_Z_H_REG 0x22
+#define ADXL355_ACT_EN_REG 0x24
+#define ADXL355_ACT_THRESH_H_REG 0x25
+#define ADXL355_ACT_THRESH_L_REG 0x26
+#define ADXL355_ACT_COUNT_REG 0x27
+#define ADXL355_FILTER_REG 0x28
+#define ADXL355_FILTER_ODR_MSK GENMASK(3, 0)
+#define ADXL355_FILTER_HPF_MSK GENMASK(6, 4)
+#define ADXL355_FIFO_SAMPLES_REG 0x29
+#define ADXL355_INT_MAP_REG 0x2A
+#define ADXL355_SYNC_REG 0x2B
+#define ADXL355_RANGE_REG 0x2C
+#define ADXL355_POWER_CTL_REG 0x2D
+#define ADXL355_POWER_CTL_MODE_MSK GENMASK(1, 0)
+#define ADXL355_SELF_TEST_REG 0x2E
+#define ADXL355_RESET_REG 0x2F
+
+#define ADXL355_DEVID_AD_VAL 0xAD
+#define ADXL355_DEVID_MST_VAL 0x1D
+#define ADXL355_PARTID_VAL 0xED
+#define ADXL355_RESET_CODE 0x52
+
+static const struct regmap_range adxl355_read_reg_range[] = {
+ regmap_reg_range(ADXL355_DEVID_AD_REG, ADXL355_FIFO_DATA_REG),
+ regmap_reg_range(ADXL355_OFFSET_X_H_REG, ADXL355_SELF_TEST_REG),
+};
+
+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);
+
+static const struct regmap_range adxl355_write_reg_range[] = {
+ regmap_reg_range(ADXL355_OFFSET_X_H_REG, ADXL355_RESET_REG),
+};
+
+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 const int adxl355_hpf_3db_multipliers[] = {
+ 0,
+ 247000,
+ 62084,
+ 15545,
+ 3862,
+ 954,
+ 238,
+};
+
+enum adxl355_chans {
+ chan_x, chan_y, chan_z,
+};
+
+struct adxl355_chan_info {
+ u8 data_reg;
+ u8 offset_reg;
+};
+
+static const struct adxl355_chan_info adxl355_chans[] = {
+ [chan_x] = {
+ .data_reg = ADXL355_XDATA3_REG,
+ .offset_reg = ADXL355_OFFSET_X_H_REG
+ },
+ [chan_y] = {
+ .data_reg = ADXL355_YDATA3_REG,
+ .offset_reg = ADXL355_OFFSET_Y_H_REG
+ },
+ [chan_z] = {
+ .data_reg = ADXL355_ZDATA3_REG,
+ .offset_reg = ADXL355_OFFSET_Z_H_REG
+ },
+};
+
+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 calibbias[3];
+ int adxl355_hpf_3db_table[7][2];
+ u8 transf_buf[3] ____cacheline_aligned;
+};
+
+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_REG,
+ ADXL355_POWER_CTL_MODE_MSK, op_mode);
+ if (ret)
+ return ret;
+
+ data->op_mode = op_mode;
+
+ return ret;
+}
+
+static void adxl355_fill_3db_frequency_table(struct adxl355_data *data)
+{
+ u32 multiplier;
+ u64 div;
+ u64 odr;
+ u64 rem;
+ int i;
+
+ 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);
+
+ data->adxl355_hpf_3db_table[i][0] = div;
+ data->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_REG, &regval);
+ if (ret)
+ 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_REG, &regval);
+ if (ret)
+ 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_REG, &regval);
+ if (ret)
+ 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_REG, ADXL355_RESET_CODE);
+ if (ret)
+ 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)
+{
+ return regmap_bulk_read(data->regmap, addr, data->transf_buf, 2);
+}
+
+static int adxl355_read_axis(struct adxl355_data *data, u8 addr)
+{
+ int ret;
+
+ ret = regmap_bulk_read(data->regmap, addr, data->transf_buf,
+ ARRAY_SIZE(data->transf_buf));
+ if (ret < 0)
+ return ret;
+
+ return get_unaligned_be24(data->transf_buf);
+}
+
+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_REG,
+ ADXL355_FILTER_ODR_MSK,
+ FIELD_PREP(ADXL355_FILTER_ODR_MSK, odr));
+ if (ret < 0)
+ goto out_unlock;
+
+ 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 unlock;
+
+ ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
+ if (ret < 0)
+ goto out_unlock;
+
+ ret = regmap_update_bits(data->regmap, ADXL355_FILTER_REG,
+ ADXL355_FILTER_HPF_MSK,
+ FIELD_PREP(ADXL355_FILTER_HPF_MSK, hpf));
+ if (!ret)
+ data->hpf_3db = hpf;
+
+out_unlock:
+ ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
+unlock:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int adxl355_set_calibbias(struct adxl355_data *data,
+ enum adxl355_chans chan, int calibbias)
+{
+ int ret = 0;
+
+ put_unaligned_be16(calibbias, data->transf_buf);
+
+ mutex_lock(&data->lock);
+
+ ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
+ if (ret < 0)
+ goto out_unlock;
+
+ ret = regmap_bulk_write(data->regmap,
+ adxl355_chans[chan].offset_reg,
+ data->transf_buf, 2);
+ if (ret)
+ goto out_unlock;
+
+ data->calibbias[chan] = calibbias;
+
+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;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ switch (chan->type) {
+ case IIO_TEMP:
+ ret = adxl355_get_temp_data(data, chan->address);
+ if (ret < 0)
+ return ret;
+ *val = get_unaligned_be16(data->transf_buf);
+
+ return IIO_VAL_INT;
+ case IIO_ACCEL:
+ ret = adxl355_read_axis(data, adxl355_chans[
+ chan->address].data_reg);
+ if (ret < 0)
+ return ret;
+ *val = sign_extend32(ret >> chan->scan_type.shift,
+ chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ default:
+ return -EINVAL;
+ }
+
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ /*
+ * 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 -110.497238
+ * and offset as -2111.25.
+ */
+ case IIO_TEMP:
+ *val = -110;
+ *val2 = 497238;
+ return IIO_VAL_INT_PLUS_MICRO;
+ /*
+ * At +/- 2g with 20-bit resolution, scale is given in datasheet
+ * as 3.9ug/LSB = 0.0000039 * 9.80665 = 0.00003824593 m/s^2.
+ */
+ case IIO_ACCEL:
+ *val = 0;
+ *val2 = 38245;
+ return IIO_VAL_INT_PLUS_NANO;
+ default:
+ return -EINVAL;
+ }
+ case IIO_CHAN_INFO_OFFSET:
+ *val = -2111;
+ *val2 = 250000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_CALIBBIAS:
+ *val = sign_extend32(data->calibbias[chan->address], 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 = data->adxl355_hpf_3db_table[data->hpf_3db][0];
+ *val2 = data->adxl355_hpf_3db_table[data->hpf_3db][1];
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ 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;
+
+ 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(data->adxl355_hpf_3db_table,
+ ARRAY_SIZE(data->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);
+
+ return adxl355_set_calibbias(data, chan->address, calibbias);
+ 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)
+{
+ struct adxl355_data *data = iio_priv(indio_dev);
+
+ 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 *)data->adxl355_hpf_3db_table;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ /* Values are stored in a 2D matrix */
+ *length = ARRAY_SIZE(data->adxl355_hpf_3db_table) * 2;
+
+ return IIO_AVAIL_LIST;
+ default:
+ return -EINVAL;
+ }
+}
+
+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_type = { \
+ .sign = 's', \
+ .realbits = 20, \
+ .storagebits = 32, \
+ .shift = 4, \
+ .endianness = IIO_BE, \
+ } \
+}
+
+static const struct iio_chan_spec adxl355_channels[] = {
+ ADXL355_ACCEL_CHANNEL(0, chan_x, X),
+ ADXL355_ACCEL_CHANNEL(1, chan_y, Y),
+ ADXL355_ACCEL_CHANNEL(2, chan_z, Z),
+ {
+ .type = IIO_TEMP,
+ .address = ADXL355_TEMP2_REG,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
+ .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->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);
+
+ 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 <[email protected]>");
+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..5a987bda9
--- /dev/null
+++ b/drivers/iio/accel/adxl355_i2c.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer I2C driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <[email protected]>
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.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 <[email protected]>");
+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..fb225aeb5
--- /dev/null
+++ b/drivers/iio/accel/adxl355_spi.c
@@ -0,0 +1,65 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ADXL355 3-Axis Digital Accelerometer SPI driver
+ *
+ * Copyright (c) 2021 Puranjay Mohan <[email protected]>
+ */
+
+#include <linux/module.h>
+#include <linux/mod_devicetable.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 <[email protected]>");
+MODULE_DESCRIPTION("ADXL355 3-Axis Digital Accelerometer SPI driver");
+MODULE_LICENSE("GPL v2");
--
2.30.1

2021-08-10 18:48:17

by Puranjay Mohan

[permalink] [raw]
Subject: [PATCH v10 1/2] dt-bindings: iio: accel: Add DT binding doc for ADXL355

Add devicetree binding document for ADXL355, a 3-Axis MEMS Accelerometer.

Signed-off-by: Puranjay Mohan <[email protected]>
---
.../bindings/iio/accel/adi,adxl355.yaml | 88 +++++++++++++++++++
1 file changed, 88 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml

diff --git a/Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml b/Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml
new file mode 100644
index 000000000..ba54d6998
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/accel/adi,adxl355.yaml
@@ -0,0 +1,88 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/accel/adi,adxl355.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices ADXL355 3-Axis, Low noise MEMS Accelerometer
+
+maintainers:
+ - Puranjay Mohan <[email protected]>
+
+description: |
+ Analog Devices ADXL355 3-Axis, Low noise MEMS Accelerometer that supports
+ both I2C & SPI interfaces
+ https://www.analog.com/en/products/adxl355.html
+
+properties:
+ compatible:
+ enum:
+ - adi,adxl355
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ minItems: 1
+ maxItems: 3
+ description: |
+ Type for DRDY should be IRQ_TYPE_EDGE_RISING.
+ Three configurable interrupt lines exist.
+
+ interrupt-names:
+ description: Specify which interrupt line is in use.
+ items:
+ enum:
+ - INT1
+ - INT2
+ - DRDY
+ minItems: 1
+ maxItems: 3
+
+ vdd-supply:
+ description: Regulator that provides power to the sensor
+
+ vddio-supply:
+ description: Regulator that provides power to the bus
+
+ spi-max-frequency: true
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ /* Example for a I2C device node */
+ accelerometer@1d {
+ compatible = "adi,adxl355";
+ reg = <0x1d>;
+ interrupt-parent = <&gpio>;
+ interrupts = <25 IRQ_TYPE_EDGE_RISING>;
+ interrupt-names = "DRDY";
+ };
+ };
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ accelerometer@0 {
+ compatible = "adi,adxl355";
+ reg = <0>;
+ spi-max-frequency = <1000000>;
+ interrupt-parent = <&gpio>;
+ interrupts = <25 IRQ_TYPE_EDGE_RISING>;
+ interrupt-names = "DRDY";
+ };
+ };
--
2.30.1

2021-08-10 19:15:01

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v10 2/2] iio: accel: Add driver support for ADXL355

On Tue, Aug 10, 2021 at 9:45 PM Puranjay Mohan <[email protected]> wrote:
>
> ADXL355 is a 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.

Thanks for an update. Seems some of the comments left unaddressed.

...

> +#include <linux/device.h>

No need. There is no user for that.
A forward declaration is enough.

> +#include <linux/regmap.h>

...

> + u32 multiplier;
> + u64 div;
> + u64 odr;
> + u64 rem;

div and rem seems of the same nature, you may put them on one line.


> + int i;
> +
> + 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);
> +
> + data->adxl355_hpf_3db_table[i][0] = div;
> + data->adxl355_hpf_3db_table[i][1] = div_u64(rem, 100000000);
> + }

Here, I didn't get if those powers-of-two are some kind of units?
If no, we may have locally defined SI prefexes for them.

> +}

...

> +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 unlock;

This...

> + ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
> + if (ret < 0)
> + goto out_unlock;

...and this are kinda easy to confuse. Please, give them better names.

> + ret = regmap_update_bits(data->regmap, ADXL355_FILTER_REG,
> + ADXL355_FILTER_HPF_MSK,
> + FIELD_PREP(ADXL355_FILTER_HPF_MSK, hpf));
> + if (!ret)
> + data->hpf_3db = hpf;
> +
> +out_unlock:
> + ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
> +unlock:
> + mutex_unlock(&data->lock);
> + return ret;
> +}
> +
> +static int adxl355_set_calibbias(struct adxl355_data *data,
> + enum adxl355_chans chan, int calibbias)
> +{

> + int ret = 0;

Redundant assignment.

...

> +out_unlock:

And as per above function, this one does more than simple unlock.

> + ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
> + mutex_unlock(&data->lock);
> + return ret;
> +}

...

> +static const struct iio_info adxl355_info = {
> + .read_raw = adxl355_read_raw,
> + .write_raw = adxl355_write_raw,
> + .read_avail = &adxl355_read_avail

+ comma.

> +};

--
With Best Regards,
Andy Shevchenko