Re: [PATCH v4 2/3] iio: accel: Support Kionix/ROHM KX022A accelerometer
From: Andy Shevchenko
Date: Fri Oct 21 2022 - 08:42:23 EST
On Fri, Oct 21, 2022 at 02:22:49PM +0300, Matti Vaittinen wrote:
> KX022A is a 3-axis accelerometer from ROHM/Kionix. The sensor features
> include variable ODRs, I2C and SPI control, FIFO/LIFO with watermark IRQ,
> tap/motion detection, wake-up & back-to-sleep events, four acceleration
> ranges (2, 4, 8 and 16g), and probably some other cool features.
>
> Add support for the basic accelerometer features such as getting the
> acceleration data via IIO. (raw reads, triggered buffer [data-ready] or
> using the WMI IRQ).
>
> Important things to be added include the double-tap, motion
> detection and wake-up as well as the runtime power management.
While I have some disagreements on some code
pieces, this version is okay to go I think.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Below a few nit-picks in case it needs to be a v5.
> Signed-off-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
>
> ---
> v3 => v4 fixes suggested by Andy:
> - styling changes
> - use str_on_off()
> - drop check for !dev
> - drop adding return value to print printed using dev_err_probe()
> - use dev_err_probe() in SPI/I2C drivers too
> - fix IRQ thread return value
>
> v2 => v3 Mostly fixes suggested by Andy
> - styling issues
> - spell-checks
> - use namespaces for exported symbols
> - drop module param
> - document the lock
> - change value written when clearing fifo
> - drop WARN_ON()
> - correctly check the return value from fwnode_irq_get_byname()
> - do not emphasize config Y over M
> - reorder struct kx022a_data from potential optimization
> - IIO_DEVICE_ATTR_RO instead of IIO_DEVICE_ATTR where applicable
> - directly include bits.h for BIT()
> - use sysfs_emit() for sysfs
> - use unique name for IRQ
> - convert read_raw() values to CPU endianess
> - fix HW-fifo size to 258 bytes
> - kx022a-spi, Fix kconfig dependency
> - disable irq (to protect timestamp / sample amount calculation) when the
> fifo flush is iniriated by user-space
>
> RFCv1 => v2 (mostly based on feedback from Jonathan):
> - Fix bunch of typos from the commit message.
> - Add missing break; to the kx022a_write_raw()
> - Fix SPI driver to use of_match_table
> - Fix indentiation in I2C driver
> - Drop struct kx022a_trigger
> - Drop cross references from Kconfig
> - Use /* */ also in file header comments
> - Misc minor styling
> - Do sensor-reset at probe
> - Support both IRQ pins
> - Implement read_avail callback
> - Use dma aligned buffers for bulk-reads
> - Use iio_trigger_poll_chained()
> - Use devm consistently
> - Drop inclusion of device.h
> - Add SPI device ID for module loading
> - Add module param for hw fifo / watermark IRQ usage
> - Fix io-vdd-supply name to match one in the bindings
> ---
> drivers/iio/accel/Kconfig | 21 +
> drivers/iio/accel/Makefile | 3 +
> drivers/iio/accel/kionix-kx022a-i2c.c | 51 ++
> drivers/iio/accel/kionix-kx022a-spi.c | 58 ++
> drivers/iio/accel/kionix-kx022a.c | 1145 +++++++++++++++++++++++++
> drivers/iio/accel/kionix-kx022a.h | 82 ++
> 6 files changed, 1360 insertions(+)
> create mode 100644 drivers/iio/accel/kionix-kx022a-i2c.c
> create mode 100644 drivers/iio/accel/kionix-kx022a-spi.c
> create mode 100644 drivers/iio/accel/kionix-kx022a.c
> create mode 100644 drivers/iio/accel/kionix-kx022a.h
>
> diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
> index ffac66db7ac9..b7fd054819d2 100644
> --- a/drivers/iio/accel/Kconfig
> +++ b/drivers/iio/accel/Kconfig
> @@ -409,6 +409,27 @@ config IIO_ST_ACCEL_SPI_3AXIS
> To compile this driver as a module, choose M here. The module
> will be called st_accel_spi.
>
> +config IIO_KX022A
> + tristate
> +
> +config IIO_KX022A_SPI
> + tristate "Kionix KX022A tri-axis digital accelerometer"
> + depends on SPI
> + select IIO_KX022A
> + select REGMAP_SPI
> + help
> + Enable support for the Kionix KX022A digital tri-axis
> + accelerometer connected to I2C interface.
> +
> +config IIO_KX022A_I2C
> + tristate "Kionix KX022A tri-axis digital accelerometer"
> + depends on I2C
> + select IIO_KX022A
> + select REGMAP_I2C
> + help
> + Enable support for the Kionix KX022A digital tri-axis
> + accelerometer connected to I2C interface.
> +
> config KXSD9
> tristate "Kionix KXSD9 Accelerometer Driver"
> select IIO_BUFFER
> diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
> index 5e45b5fa5ab5..311ead9c3ef1 100644
> --- a/drivers/iio/accel/Makefile
> +++ b/drivers/iio/accel/Makefile
> @@ -40,6 +40,9 @@ obj-$(CONFIG_FXLS8962AF) += fxls8962af-core.o
> obj-$(CONFIG_FXLS8962AF_I2C) += fxls8962af-i2c.o
> obj-$(CONFIG_FXLS8962AF_SPI) += fxls8962af-spi.o
> obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
> +obj-$(CONFIG_IIO_KX022A) += kionix-kx022a.o
> +obj-$(CONFIG_IIO_KX022A_I2C) += kionix-kx022a-i2c.o
> +obj-$(CONFIG_IIO_KX022A_SPI) += kionix-kx022a-spi.o
> obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
> obj-$(CONFIG_KXSD9) += kxsd9.o
> obj-$(CONFIG_KXSD9_SPI) += kxsd9-spi.o
> diff --git a/drivers/iio/accel/kionix-kx022a-i2c.c b/drivers/iio/accel/kionix-kx022a-i2c.c
> new file mode 100644
> index 000000000000..6510f8d62b85
> --- /dev/null
> +++ b/drivers/iio/accel/kionix-kx022a-i2c.c
> @@ -0,0 +1,51 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2022 ROHM Semiconductors
> + *
> + * ROHM/KIONIX KX022A accelerometer driver
> + */
> +
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +
> +#include "kionix-kx022a.h"
> +
> +static int kx022a_i2c_probe(struct i2c_client *i2c)
> +{
> + struct device *dev = &i2c->dev;
> + struct regmap *regmap;
> +
> + if (!i2c->irq) {
> + dev_err(dev, "No IRQ configured\n");
> + return -EINVAL;
> + }
> +
> + regmap = devm_regmap_init_i2c(i2c, &kx022a_regmap);
> + if (IS_ERR(regmap))
> + return dev_err_probe(dev, PTR_ERR(regmap),
> + "Failed to initialize Regmap\n");
> +
> + return kx022a_probe_internal(dev);
> +}
> +
> +static const struct of_device_id kx022a_of_match[] = {
> + { .compatible = "kionix,kx022a", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, kx022a_of_match);
> +
> +static struct i2c_driver kx022a_i2c_driver = {
> + .driver = {
> + .name = "kx022a-i2c",
> + .of_match_table = kx022a_of_match,
> + },
> + .probe_new = kx022a_i2c_probe,
> +};
> +module_i2c_driver(kx022a_i2c_driver);
> +
> +MODULE_DESCRIPTION("ROHM/Kionix KX022A accelerometer driver");
> +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS(KIONIX_ACCEL);
> diff --git a/drivers/iio/accel/kionix-kx022a-spi.c b/drivers/iio/accel/kionix-kx022a-spi.c
> new file mode 100644
> index 000000000000..7fe3b0aba1fe
> --- /dev/null
> +++ b/drivers/iio/accel/kionix-kx022a-spi.c
> @@ -0,0 +1,58 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2022 ROHM Semiconductors
> + *
> + * ROHM/KIONIX KX022A accelerometer driver
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/regmap.h>
> +#include <linux/spi/spi.h>
> +
> +#include "kionix-kx022a.h"
> +
> +static int kx022a_spi_probe(struct spi_device *spi)
> +{
> + struct device *dev = &spi->dev;
> + struct regmap *regmap;
> +
> + if (!spi->irq) {
> + dev_err(dev, "No IRQ configured\n");
> + return -EINVAL;
> + }
> +
> + regmap = devm_regmap_init_spi(spi, &kx022a_regmap);
> + if (IS_ERR(regmap))
> + return dev_err_probe(dev, PTR_ERR(regmap),
> + "Failed to initialize Regmap\n");
> +
> + return kx022a_probe_internal(dev);
> +}
> +
> +static const struct spi_device_id kx022a_id[] = {
> + { "kx022a" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, kx022a_id);
> +
> +static const struct of_device_id kx022a_of_match[] = {
> + { .compatible = "kionix,kx022a", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, kx022a_of_match);
> +
> +static struct spi_driver kx022a_spi_driver = {
> + .driver = {
> + .name = "kx022a-spi",
> + .of_match_table = kx022a_of_match,
> + },
> + .probe = kx022a_spi_probe,
> + .id_table = kx022a_id,
> +};
> +module_spi_driver(kx022a_spi_driver);
> +
> +MODULE_DESCRIPTION("ROHM/Kionix kx022A accelerometer driver");
> +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> +MODULE_IMPORT_NS(KIONIX_ACCEL);
> diff --git a/drivers/iio/accel/kionix-kx022a.c b/drivers/iio/accel/kionix-kx022a.c
> new file mode 100644
> index 000000000000..5a8622c8127b
> --- /dev/null
> +++ b/drivers/iio/accel/kionix-kx022a.c
> @@ -0,0 +1,1145 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2022 ROHM Semiconductors
> + *
> + * ROHM/KIONIX KX022A accelerometer driver
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/moduleparam.h>
> +#include <linux/mutex.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/slab.h>
> +#include <linux/string_helpers.h>
> +#include <linux/units.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +#include <linux/iio/trigger.h>
> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +#include "kionix-kx022a.h"
> +
> +/*
> + * The KX022A has FIFO which can store 43 samples of HiRes data from 2
> + * channels. This equals to 43 (samples) * 3 (channels) * 2 (bytes/sample) to
> + * 258 bytes of sample data. The quirk to know is that the amount of bytes in
> + * the FIFO is advertised via 8 bit register (max value 255). The thing to note
> + * is that full 258 bytes of data is indicated using the max value 255.
> + */
> +#define KX022A_FIFO_LENGTH 43
> +#define KX022A_FIFO_FULL_VALUE 255
> +#define KX022A_SOFT_RESET_WAIT_TIME_US (5 * USEC_PER_MSEC)
> +#define KX022A_SOFT_RESET_TOTAL_WAIT_TIME_US (500 * USEC_PER_MSEC)
> +
> +/* 3 axis, 2 bytes of data for each of the axis */
> +#define KX022A_FIFO_SAMPLES_SIZE_BYTES 6
> +#define KX022A_FIFO_MAX_BYTES \
> + (KX022A_FIFO_LENGTH * KX022A_FIFO_SAMPLES_SIZE_BYTES)
> +
> +enum {
> + KX022A_STATE_SAMPLE,
> + KX022A_STATE_FIFO,
> +};
> +
> +/* Regmap configs */
> +static const struct regmap_range kx022a_volatile_ranges[] = {
> + {
> + .range_min = KX022A_REG_XHP_L,
> + .range_max = KX022A_REG_COTR,
> + }, {
> + .range_min = KX022A_REG_TSCP,
> + .range_max = KX022A_REG_INT_REL,
> + }, {
> + /* The reset bit will be cleared by sensor */
> + .range_min = KX022A_REG_CNTL2,
> + .range_max = KX022A_REG_CNTL2,
> + }, {
> + .range_min = KX022A_REG_BUF_STATUS_1,
> + .range_max = KX022A_REG_BUF_READ,
> + },
> +};
> +
> +static const struct regmap_access_table kx022a_volatile_regs = {
> + .yes_ranges = &kx022a_volatile_ranges[0],
> + .n_yes_ranges = ARRAY_SIZE(kx022a_volatile_ranges),
> +};
> +
> +static const struct regmap_range kx022a_precious_ranges[] = {
> + {
> + .range_min = KX022A_REG_INT_REL,
> + .range_max = KX022A_REG_INT_REL,
> + },
> +};
> +
> +static const struct regmap_access_table kx022a_precious_regs = {
> + .yes_ranges = &kx022a_precious_ranges[0],
> + .n_yes_ranges = ARRAY_SIZE(kx022a_precious_ranges),
> +};
> +
> +/*
> + * The HW does not set WHO_AM_I reg as read-only but we don't want to write it
> + * so we still include it in the read-only ranges.
> + */
> +static const struct regmap_range kx022a_read_only_ranges[] = {
> + {
> + .range_min = KX022A_REG_XHP_L,
> + .range_max = KX022A_REG_INT_REL,
> + }, {
> + .range_min = KX022A_REG_BUF_STATUS_1,
> + .range_max = KX022A_REG_BUF_STATUS_2,
> + }, {
> + .range_min = KX022A_REG_BUF_READ,
> + .range_max = KX022A_REG_BUF_READ,
> + },
> +};
> +
> +static const struct regmap_access_table kx022a_ro_regs = {
> + .no_ranges = &kx022a_read_only_ranges[0],
> + .n_no_ranges = ARRAY_SIZE(kx022a_read_only_ranges),
> +};
> +
> +static const struct regmap_range kx022a_write_only_ranges[] = {
> + {
> + .range_min = KX022A_REG_BTS_WUF_TH,
> + .range_max = KX022A_REG_BTS_WUF_TH,
> + }, {
> + .range_min = KX022A_REG_MAN_WAKE,
> + .range_max = KX022A_REG_MAN_WAKE,
> + }, {
> + .range_min = KX022A_REG_SELF_TEST,
> + .range_max = KX022A_REG_SELF_TEST,
> + }, {
> + .range_min = KX022A_REG_BUF_CLEAR,
> + .range_max = KX022A_REG_BUF_CLEAR,
> + },
> +};
> +
> +static const struct regmap_access_table kx022a_wo_regs = {
> + .no_ranges = &kx022a_write_only_ranges[0],
> + .n_no_ranges = ARRAY_SIZE(kx022a_write_only_ranges),
> +};
> +
> +static const struct regmap_range kx022a_noinc_read_ranges[] = {
> + {
> + .range_min = KX022A_REG_BUF_READ,
> + .range_max = KX022A_REG_BUF_READ,
> + },
> +};
> +
> +static const struct regmap_access_table kx022a_nir_regs = {
> + .yes_ranges = &kx022a_noinc_read_ranges[0],
> + .n_yes_ranges = ARRAY_SIZE(kx022a_noinc_read_ranges),
> +};
> +
> +const struct regmap_config kx022a_regmap = {
> + .reg_bits = 8,
> + .val_bits = 8,
> + .volatile_table = &kx022a_volatile_regs,
> + .rd_table = &kx022a_wo_regs,
> + .wr_table = &kx022a_ro_regs,
> + .rd_noinc_table = &kx022a_nir_regs,
> + .precious_table = &kx022a_precious_regs,
> + .max_register = KX022A_MAX_REGISTER,
> + .cache_type = REGCACHE_RBTREE,
> +};
> +EXPORT_SYMBOL_NS_GPL(kx022a_regmap, KIONIX_ACCEL);
> +
> +struct kx022a_data {
> + struct regmap *regmap;
> + struct iio_trigger *trig;
> + struct device *dev;
> + struct iio_mount_matrix orientation;
> + int64_t timestamp, old_timestamp;
> +
> + int irq;
> + int inc_reg;
> + int ien_reg;
> +
> + unsigned int g_range;
> + unsigned int state;
> + unsigned int odr_ns;
> +
> + bool trigger_enabled;
> + /*
> + * Prevent toggling the sensor stby/active state (PC1 bit) in the
> + * middle of a configuration, or when the fifo is enabled. Also,
> + * protect the data stored/retrieved from this structure from
> + * concurrent accesses.
> + */
> + struct mutex mutex;
> + u8 watermark;
> +
> + /* 3 x 16bit accel data + timestamp */
> + __le16 buffer[8] __aligned(IIO_DMA_MINALIGN);
> + struct {
> + __le16 channels[3];
> + s64 ts __aligned(8);
> + } scan;
> +};
> +
> +static const struct iio_mount_matrix *
> +kx022a_get_mount_matrix(const struct iio_dev *idev,
> + const struct iio_chan_spec *chan)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> +
> + return &data->orientation;
> +}
> +
> +enum {
> + AXIS_X,
> + AXIS_Y,
> + AXIS_Z,
> + AXIS_MAX
> +};
> +
> +static const unsigned long kx022a_scan_masks[] = {
> + BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z), 0
> +};
> +
> +static const struct iio_chan_spec_ext_info kx022a_ext_info[] = {
> + IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kx022a_get_mount_matrix),
> + { }
> +};
> +
> +#define KX022A_ACCEL_CHAN(axis, index) \
> +{ \
> + .type = IIO_ACCEL, \
> + .modified = 1, \
> + .channel2 = IIO_MOD_##axis, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .info_mask_shared_by_type_available = \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> + .ext_info = kx022a_ext_info, \
> + .address = KX022A_REG_##axis##OUT_L, \
> + .scan_index = index, \
> + .scan_type = { \
> + .sign = 's', \
> + .realbits = 16, \
> + .storagebits = 16, \
> + .endianness = IIO_LE, \
> + }, \
> +}
> +
> +static const struct iio_chan_spec kx022a_channels[] = {
> + KX022A_ACCEL_CHAN(X, 0),
> + KX022A_ACCEL_CHAN(Y, 1),
> + KX022A_ACCEL_CHAN(Z, 2),
> + IIO_CHAN_SOFT_TIMESTAMP(3),
> +};
> +
> +/*
> + * The sensor HW can support ODR up to 1600 Hz, which is beyond what most of the
> + * Linux CPUs can handle without dropping samples. Also, the low power mode is
> + * not available for higher sample rates. Thus, the driver only supports 200 Hz
> + * and slower ODRs. The slowest is 0.78 Hz.
> + */
> +static const int kx022a_accel_samp_freq_table[][2] = {
> + { 0, 780000 },
> + { 1, 563000 },
> + { 3, 125000 },
> + { 6, 250000 },
> + { 12, 500000 },
> + { 25, 0 },
> + { 50, 0 },
> + { 100, 0 },
> + { 200, 0 },
> +};
> +
> +static const unsigned int kx022a_odrs[] = {
> + 1282051282,
> + 639795266,
> + 320 * MEGA,
> + 160 * MEGA,
> + 80 * MEGA,
> + 40 * MEGA,
> + 20 * MEGA,
> + 10 * MEGA,
> + 5 * MEGA,
> +};
> +
> +/*
> + * range is typically +-2G/4G/8G/16G, distributed over the amount of bits.
> + * The scale table can be calculated using
> + * (range / 2^bits) * g = (range / 2^bits) * 9.80665 m/s^2
> + * => KX022A uses 16 bit (HiRes mode - assume the low 8 bits are zeroed
> + * in low-power mode(?) )
> + * => +/-2G => 4 / 2^16 * 9,80665 * 10^6 (to scale to micro)
> + * => +/-2G - 598.550415
> + * +/-4G - 1197.10083
> + * +/-8G - 2394.20166
> + * +/-16G - 4788.40332
> + */
> +static const int kx022a_scale_table[][2] = {
> + { 598, 550415 },
> + { 1197, 100830 },
> + { 2394, 201660 },
> + { 4788, 403320 },
> +};
> +
> +static int kx022a_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 *)kx022a_accel_samp_freq_table;
> + *length = ARRAY_SIZE(kx022a_accel_samp_freq_table) *
> + ARRAY_SIZE(kx022a_accel_samp_freq_table[0]);
> + *type = IIO_VAL_INT_PLUS_MICRO;
> + return IIO_AVAIL_LIST;
> + case IIO_CHAN_INFO_SCALE:
> + *vals = (const int *)kx022a_scale_table;
> + *length = ARRAY_SIZE(kx022a_scale_table) *
> + ARRAY_SIZE(kx022a_scale_table[0]);
> + *type = IIO_VAL_INT_PLUS_MICRO;
> + return IIO_AVAIL_LIST;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +#define KX022A_DEFAULT_PERIOD_NS (20 * NSEC_PER_MSEC)
> +
> +static void kx022a_reg2freq(unsigned int val, int *val1, int *val2)
> +{
> + *val1 = kx022a_accel_samp_freq_table[val & KX022A_MASK_ODR][0];
> + *val2 = kx022a_accel_samp_freq_table[val & KX022A_MASK_ODR][1];
> +}
> +
> +static void kx022a_reg2scale(unsigned int val, unsigned int *val1,
> + unsigned int *val2)
> +{
> + val &= KX022A_MASK_GSEL;
> + val >>= KX022A_GSEL_SHIFT;
> +
> + *val1 = kx022a_scale_table[val][0];
> + *val2 = kx022a_scale_table[val][1];
> +}
> +
> +static int kx022a_turn_on_off_unlocked(struct kx022a_data *data, bool on)
> +{
> + int ret;
> +
> + if (on)
> + ret = regmap_set_bits(data->regmap, KX022A_REG_CNTL,
> + KX022A_MASK_PC1);
> + else
> + ret = regmap_clear_bits(data->regmap, KX022A_REG_CNTL,
> + KX022A_MASK_PC1);
> + if (ret)
> + dev_err(data->dev, "Turn %s fail %d\n", str_on_off(on), ret);
> +
> + return ret;
> +
> +}
> +
> +static int kx022a_turn_off_lock(struct kx022a_data *data)
> +{
> + int ret;
> +
> + mutex_lock(&data->mutex);
> + ret = kx022a_turn_on_off_unlocked(data, false);
> + if (ret)
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static int kx022a_turn_on_unlock(struct kx022a_data *data)
> +{
> + int ret;
> +
> + ret = kx022a_turn_on_off_unlocked(data, true);
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static int kx022a_write_raw(struct iio_dev *idev,
> + struct iio_chan_spec const *chan,
> + int val, int val2, long mask)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> + int ret, n;
> +
> + /*
> + * We should not allow changing scale or frequency when FIFO is running
> + * as it will mess the timestamp/scale for samples existing in the
> + * buffer. If this turns out to be an issue we can later change logic
> + * to internally flush the fifo before reconfiguring so the samples in
> + * fifo keep matching the freq/scale settings. (Such setup could cause
> + * issues if users trust the watermark to be reached within known
> + * time-limit).
> + */
> + ret = iio_device_claim_direct_mode(idev);
> + if (ret)
> + return ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + n = ARRAY_SIZE(kx022a_accel_samp_freq_table);
> +
> + while (n--)
> + if (val == kx022a_accel_samp_freq_table[n][0] &&
> + val2 == kx022a_accel_samp_freq_table[n][1])
> + break;
> + if (n < 0) {
> + ret = -EINVAL;
> + goto unlock_out;
> + }
> + ret = kx022a_turn_off_lock(data);
> + if (ret)
> + break;
> +
> + ret = regmap_update_bits(data->regmap,
> + KX022A_REG_ODCNTL,
> + KX022A_MASK_ODR, n);
> + data->odr_ns = kx022a_odrs[n];
> + kx022a_turn_on_unlock(data);
> + break;
> + case IIO_CHAN_INFO_SCALE:
> + n = ARRAY_SIZE(kx022a_scale_table);
> +
> + while (n-- > 0)
> + if (val == kx022a_scale_table[n][0] &&
> + val2 == kx022a_scale_table[n][1])
> + break;
> + if (n < 0) {
> + ret = -EINVAL;
> + goto unlock_out;
> + }
> +
> + ret = kx022a_turn_off_lock(data);
> + if (ret)
> + break;
> +
> + ret = regmap_update_bits(data->regmap, KX022A_REG_CNTL,
> + KX022A_MASK_GSEL,
> + n << KX022A_GSEL_SHIFT);
> + kx022a_turn_on_unlock(data);
> + break;
> + default:
> + ret = -EINVAL;
> + break;
> + }
> +
> +unlock_out:
> + iio_device_release_direct_mode(idev);
> +
> + return ret;
> +}
> +
> +static int kx022a_fifo_set_wmi(struct kx022a_data *data)
> +{
> + u8 threshold;
> +
> + threshold = data->watermark;
> +
> + return regmap_update_bits(data->regmap, KX022A_REG_BUF_CNTL1,
> + KX022A_MASK_WM_TH, threshold);
> +}
> +
> +static int kx022a_get_axis(struct kx022a_data *data,
> + struct iio_chan_spec const *chan,
> + int *val)
> +{
> + int ret;
> +
> + ret = regmap_bulk_read(data->regmap, chan->address, &data->buffer[0],
> + sizeof(__le16));
> + if (ret)
> + return ret;
> +
> + *val = le16_to_cpu(data->buffer[0]);
> +
> + return IIO_VAL_INT;
> +}
> +
> +static int kx022a_read_raw(struct iio_dev *idev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2, long mask)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> + unsigned int regval;
> + int ret;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + ret = iio_device_claim_direct_mode(idev);
> + if (ret)
> + return ret;
> +
> + mutex_lock(&data->mutex);
> + ret = kx022a_get_axis(data, chan, val);
> + mutex_unlock(&data->mutex);
> +
> + iio_device_release_direct_mode(idev);
> +
> + return ret;
> +
> + case IIO_CHAN_INFO_SAMP_FREQ:
> + ret = regmap_read(data->regmap, KX022A_REG_ODCNTL, ®val);
> + if (ret)
> + return ret;
> +
> + if ((regval & KX022A_MASK_ODR) >
> + ARRAY_SIZE(kx022a_accel_samp_freq_table)) {
> + dev_err(data->dev, "Invalid ODR\n");
> + return -EINVAL;
> + }
> +
> + kx022a_reg2freq(regval, val, val2);
> +
> + return IIO_VAL_INT_PLUS_MICRO;
> +
> + case IIO_CHAN_INFO_SCALE:
> + ret = regmap_read(data->regmap, KX022A_REG_CNTL, ®val);
> + if (ret < 0)
> + return ret;
> +
> + kx022a_reg2scale(regval, val, val2);
> +
> + return IIO_VAL_INT_PLUS_MICRO;
> + }
> +
> + return -EINVAL;
> +};
> +
> +static int kx022a_validate_trigger(struct iio_dev *idev,
> + struct iio_trigger *trig)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> +
> + if (data->trig != trig)
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int kx022a_set_watermark(struct iio_dev *idev, unsigned int val)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> +
> + if (val > KX022A_FIFO_LENGTH)
> + val = KX022A_FIFO_LENGTH;
> +
> + mutex_lock(&data->mutex);
> + data->watermark = val;
> + mutex_unlock(&data->mutex);
> +
> + return 0;
> +}
> +
> +static ssize_t hwfifo_enabled_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct iio_dev *idev = dev_to_iio_dev(dev);
> + struct kx022a_data *data = iio_priv(idev);
> + bool state;
> +
> + mutex_lock(&data->mutex);
> + state = data->state;
> + mutex_unlock(&data->mutex);
> +
> + return sysfs_emit(buf, "%d\n", state);
> +}
> +
> +static ssize_t hwfifo_watermark_show(struct device *dev,
> + struct device_attribute *attr,
> + char *buf)
> +{
> + struct iio_dev *idev = dev_to_iio_dev(dev);
> + struct kx022a_data *data = iio_priv(idev);
> + int wm;
> +
> + mutex_lock(&data->mutex);
> + wm = data->watermark;
> + mutex_unlock(&data->mutex);
> +
> + return sysfs_emit(buf, "%d\n", wm);
> +}
> +
> +static IIO_DEVICE_ATTR_RO(hwfifo_enabled, 0);
> +static IIO_DEVICE_ATTR_RO(hwfifo_watermark, 0);
> +
> +static const struct attribute *kx022a_fifo_attributes[] = {
> + &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
> + &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
> + NULL
> +};
> +
> +static int kx022a_drop_fifo_contents(struct kx022a_data *data)
> +{
> + /*
> + * We must clear the old time-stamp to avoid computing the timestamps
> + * based on samples acquired when buffer was last enabled.
> + *
> + * We don't need to protect the timestamp as long as we are only
> + * called from fifo-disable where we can guarantee the sensor is not
> + * triggering interrupts and where the mutex is locked to prevent the
> + * user-space access.
> + */
> + data->timestamp = 0;
> +
> + return regmap_write(data->regmap, KX022A_REG_BUF_CLEAR, 0x0);
> +}
> +
> +static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
> + bool irq)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> + struct device *dev = regmap_get_device(data->regmap);
> + u16 buffer[KX022A_FIFO_LENGTH * 3];
> + uint64_t sample_period;
> + int count, fifo_bytes;
> + bool renable = false;
> + int64_t tstamp;
> + int ret, i;
> +
> + ret = regmap_read(data->regmap, KX022A_REG_BUF_STATUS_1, &fifo_bytes);
> + if (ret) {
> + dev_err(dev, "Error reading buffer status\n");
> + return ret;
> + }
> +
> + /* Let's not overflow if we for some reason get bogus value from i2c */
> + if (fifo_bytes == KX022A_FIFO_FULL_VALUE)
> + fifo_bytes = KX022A_FIFO_MAX_BYTES;
> +
> + if (fifo_bytes % KX022A_FIFO_SAMPLES_SIZE_BYTES)
> + dev_warn(data->dev, "Bad FIFO alignment. Data may be corrupt\n");
> +
> + count = fifo_bytes / KX022A_FIFO_SAMPLES_SIZE_BYTES;
> + if (!count)
> + return 0;
> +
> + /*
> + * If we are being called from IRQ handler we know the stored timestamp
> + * is fairly accurate for the last stored sample. Otherwise, if we are
> + * called as a result of a read operation from userspace and hence
> + * before the watermark interrupt was triggered, take a timestamp
> + * now. We can fall anywhere in between two samples so the error in this
> + * case is at most one sample period.
> + */
> + if (!irq) {
> + /*
> + * We need to have the IRQ disabled or we risk of messing-up
> + * the timestamps. If we are ran from IRQ, then the
> + * IRQF_ONESHOT has us covered - but if we are ran by the
> + * user-space read we need to disable the IRQ to be on a safe
> + * side. We do this usng synchronous disable so that if the
> + * IRQ thread is being ran on other CPU we wait for it to be
> + * finished.
> + */
> + disable_irq(data->irq);
> + renable = true;
> +
> + data->old_timestamp = data->timestamp;
> + data->timestamp = iio_get_time_ns(idev);
> + }
> +
> + /*
> + * Approximate timestamps for each of the sample based on the sampling
> + * frequency, timestamp for last sample and number of samples.
> + *
> + * We'd better not use the current bandwidth settings to compute the
> + * sample period. The real sample rate varies with the device and
> + * small variation adds when we store a large number of samples.
> + *
> + * To avoid this issue we compute the actual sample period ourselves
> + * based on the timestamp delta between the last two flush operations.
> + */
> + if (data->old_timestamp) {
> + sample_period = data->timestamp - data->old_timestamp;
> + do_div(sample_period, count);
> + } else {
> + sample_period = data->odr_ns;
> + }
> + tstamp = data->timestamp - (count - 1) * sample_period;
> +
> + if (samples && count > samples) {
> + /*
> + * Here we leave some old samples to the buffer. We need to
> + * adjust the timestamp to match the first sample in the buffer
> + * or we will miscalculate the sample_period at next round.
> + */
> + data->timestamp -= (count - samples) * sample_period;
> + count = samples;
> + }
> +
> + fifo_bytes = count * KX022A_FIFO_SAMPLES_SIZE_BYTES;
> + ret = regmap_noinc_read(data->regmap, KX022A_REG_BUF_READ,
> + buffer, fifo_bytes);
> + if (ret)
> + goto renable_out;
> +
> + for (i = 0; i < count; i++) {
> + u16 *sam = &buffer[i * 3];
> + __le16 *chs;
> + int bit;
> +
> + chs = &data->scan.channels[0];
> + for_each_set_bit(bit, idev->active_scan_mask, AXIS_MAX)
> + memcpy(&chs[bit], &sam[bit], sizeof(*chs));
> +
> + iio_push_to_buffers_with_timestamp(idev, &data->scan, tstamp);
> +
> + tstamp += sample_period;
> + }
> +
> + ret = count;
> +
> +renable_out:
> + if (renable)
> + enable_irq(data->irq);
> +
> + return ret;
> +}
> +
> +static int kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> + int ret;
> +
> + mutex_lock(&data->mutex);
> + ret = __kx022a_fifo_flush(idev, samples, false);
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static const struct iio_info kx022a_info = {
> + .read_raw = &kx022a_read_raw,
> + .write_raw = &kx022a_write_raw,
> + .read_avail = &kx022a_read_avail,
> +
> + .validate_trigger = kx022a_validate_trigger,
> + .hwfifo_set_watermark = kx022a_set_watermark,
> + .hwfifo_flush_to_buffer = kx022a_fifo_flush,
> +};
> +
> +static int kx022a_set_drdy_irq(struct kx022a_data *data, bool en)
> +{
> + if (en)
> + return regmap_set_bits(data->regmap, KX022A_REG_CNTL,
> + KX022A_MASK_DRDY);
> +
> + return regmap_clear_bits(data->regmap, KX022A_REG_CNTL,
> + KX022A_MASK_DRDY);
> +}
> +
> +static int kx022a_prepare_irq_pin(struct kx022a_data *data)
> +{
> + /* Enable IRQ1 pin. Set polarity to active low */
> + int mask = KX022A_MASK_IEN | KX022A_MASK_IPOL |
> + KX022A_MASK_ITYP;
> + int val = KX022A_MASK_IEN | KX022A_IPOL_LOW |
> + KX022A_ITYP_LEVEL;
> + int ret;
> +
> + ret = regmap_update_bits(data->regmap, data->inc_reg, mask, val);
> + if (ret)
> + return ret;
> +
> + /* We enable WMI to IRQ pin only at buffer_enable */
> + mask = KX022A_MASK_INS2_DRDY;
> +
> + return regmap_set_bits(data->regmap, data->ien_reg, mask);
> +}
> +
> +static int kx022a_fifo_disable(struct kx022a_data *data)
> +{
> + int ret = 0;
> +
> + ret = kx022a_turn_off_lock(data);
> + if (ret)
> + return ret;
> +
> + ret = regmap_clear_bits(data->regmap, data->ien_reg, KX022A_MASK_WMI);
> + if (ret)
> + goto unlock_out;
> +
> + ret = regmap_clear_bits(data->regmap, KX022A_REG_BUF_CNTL2,
> + KX022A_MASK_BUF_EN);
> + if (ret)
> + goto unlock_out;
> + data->state &= (~KX022A_STATE_FIFO);
Too many parentheses.
> + kx022a_drop_fifo_contents(data);
> +
> + return kx022a_turn_on_unlock(data);
> +
> +unlock_out:
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static int kx022a_buffer_predisable(struct iio_dev *idev)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> +
> + if (iio_device_get_current_mode(idev) == INDIO_BUFFER_TRIGGERED)
> + return 0;
> +
> + return kx022a_fifo_disable(data);
> +}
> +
> +static int kx022a_fifo_enable(struct kx022a_data *data)
> +{
> + int ret;
> +
> + ret = kx022a_turn_off_lock(data);
> + if (ret)
> + return ret;
> +
> + /* Update watermark to HW */
> + ret = kx022a_fifo_set_wmi(data);
> + if (ret)
> + goto unlock_out;
> +
> + /* Enable buffer */
> + ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2,
> + KX022A_MASK_BUF_EN);
> + if (ret)
> + goto unlock_out;
> +
> + data->state |= KX022A_STATE_FIFO;
> + ret = regmap_set_bits(data->regmap, data->ien_reg,
> + KX022A_MASK_WMI);
> + if (ret)
> + goto unlock_out;
> +
> + return kx022a_turn_on_unlock(data);
> +
> +unlock_out:
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static int kx022a_buffer_postenable(struct iio_dev *idev)
> +{
> + struct kx022a_data *data = iio_priv(idev);
> +
> + /*
> + * If we use data-ready trigger, then the IRQ masks should be handled by
> + * trigger enable and the hardware buffer is not used but we just update
> + * results to the IIO fifo when data-ready triggers.
> + */
> + if (iio_device_get_current_mode(idev) == INDIO_BUFFER_TRIGGERED)
> + return 0;
> +
> + return kx022a_fifo_enable(data);
> +}
> +
> +static const struct iio_buffer_setup_ops kx022a_buffer_ops = {
> + .postenable = kx022a_buffer_postenable,
> + .predisable = kx022a_buffer_predisable,
> +};
> +
> +static irqreturn_t kx022a_trigger_handler(int irq, void *p)
> +{
> + struct iio_poll_func *pf = p;
> + struct iio_dev *idev = pf->indio_dev;
> + struct kx022a_data *data = iio_priv(idev);
> + int ret;
> +
> + ret = regmap_bulk_read(data->regmap, KX022A_REG_XOUT_L, data->buffer,
> + KX022A_FIFO_SAMPLES_SIZE_BYTES);
> + if (ret < 0)
> + goto err_read;
> +
> + iio_push_to_buffers_with_timestamp(idev, data->buffer, pf->timestamp);
> +err_read:
> + iio_trigger_notify_done(idev->trig);
> +
> + return IRQ_HANDLED;
> +}
> +
> +/* Get timestamps and wake the thread if we need to read data */
> +static irqreturn_t kx022a_irq_handler(int irq, void *private)
> +{
> + struct iio_dev *idev = private;
> + struct kx022a_data *data = iio_priv(idev);
> +
> + data->old_timestamp = data->timestamp;
> + data->timestamp = iio_get_time_ns(idev);
> +
> + if (data->state & KX022A_STATE_FIFO || data->trigger_enabled)
> + return IRQ_WAKE_THREAD;
> +
> + return IRQ_NONE;
> +}
> +
> +/*
> + * WMI and data-ready IRQs are acked when results are read. If we add
> + * TILT/WAKE or other IRQs - then we may need to implement the acking
> + * (which is racy).
> + */
> +static irqreturn_t kx022a_irq_thread_handler(int irq, void *private)
> +{
> + struct iio_dev *idev = private;
> + struct kx022a_data *data = iio_priv(idev);
> + int ret = IRQ_NONE;
Strictly speaking this should be
irqreturn_t ret = ...
> + mutex_lock(&data->mutex);
> +
> + if (data->trigger_enabled) {
> + iio_trigger_poll_chained(data->trig);
> + ret = IRQ_HANDLED;
> + }
> +
> + if (data->state & KX022A_STATE_FIFO) {
> + int ok;
> +
> + ok = __kx022a_fifo_flush(idev, KX022A_FIFO_LENGTH, true);
> + if (ok > 0)
> + ret = IRQ_HANDLED;
> + }
> +
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static int kx022a_trigger_set_state(struct iio_trigger *trig,
> + bool state)
> +{
> + struct kx022a_data *data = iio_trigger_get_drvdata(trig);
> + int ret = 0;
> +
> + mutex_lock(&data->mutex);
> +
> + if (data->trigger_enabled == state)
> + goto unlock_out;
> +
> + if (data->state & KX022A_STATE_FIFO) {
> + dev_warn(data->dev, "Can't set trigger when FIFO enabled\n");
> + ret = -EBUSY;
> + goto unlock_out;
> + }
> +
> + ret = kx022a_turn_on_off_unlocked(data, false);
> + if (ret)
> + goto unlock_out;
> +
> + data->trigger_enabled = state;
> + ret = kx022a_set_drdy_irq(data, state);
> + if (ret)
> + goto unlock_out;
> +
> + ret = kx022a_turn_on_off_unlocked(data, true);
> +
> +unlock_out:
> + mutex_unlock(&data->mutex);
> +
> + return ret;
> +}
> +
> +static const struct iio_trigger_ops kx022a_trigger_ops = {
> + .set_trigger_state = kx022a_trigger_set_state,
> +};
> +
> +static int kx022a_chip_init(struct kx022a_data *data)
> +{
> + int ret, val;
> +
> + /* Reset the senor */
> + ret = regmap_write(data->regmap, KX022A_REG_CNTL2, KX022A_MASK_SRST);
> + if (ret)
> + return ret;
> +
> + /*
> + * I've seen I2C read failures if we poll too fast after the sensor
> + * reset. Slight delay gives I2C block the time to recover.
> + */
> + msleep(1);
> +
> + ret = regmap_read_poll_timeout(data->regmap, KX022A_REG_CNTL2, val,
> + !(val & KX022A_MASK_SRST),
> + KX022A_SOFT_RESET_WAIT_TIME_US,
> + KX022A_SOFT_RESET_TOTAL_WAIT_TIME_US);
> + if (ret) {
> + dev_err(data->dev, "Sensor reset %s\n",
> + val & KX022A_MASK_SRST ? "timeout" : "fail#");
> + return ret;
> + }
> +
> + ret = regmap_reinit_cache(data->regmap, &kx022a_regmap);
> + if (ret) {
> + dev_err(data->dev, "Failed to reinit reg cache\n");
> + return ret;
> + }
> +
> + /* set data res 16bit */
> + ret = regmap_set_bits(data->regmap, KX022A_REG_BUF_CNTL2,
> + KX022A_MASK_BRES16);
> + if (ret) {
> + dev_err(data->dev, "Failed to set data resolution\n");
> + return ret;
> + }
> +
> + return kx022a_prepare_irq_pin(data);
> +}
> +
> +int kx022a_probe_internal(struct device *dev)
> +{
> + static const char * const regulator_names[] = {"io-vdd", "vdd"};
> + struct iio_trigger *indio_trig;
> + struct fwnode_handle *fwnode;
> + struct kx022a_data *data;
> + struct regmap *regmap;
> + unsigned int chip_id;
> + struct iio_dev *idev;
> + int ret, irq;
> + char *name;
> +
> + regmap = dev_get_regmap(dev, NULL);
> + if (!regmap) {
> + dev_err(dev, "no regmap\n");
> + return -EINVAL;
> + }
> +
> + idev = devm_iio_device_alloc(dev, sizeof(*data));
> + if (!idev)
> + return -ENOMEM;
> +
> + data = iio_priv(idev);
> +
> + /*
> + * VDD is the analog and digital domain voltage supply and
> + * IO_VDD is the digital I/O voltage supply.
> + */
> + ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(regulator_names),
> + regulator_names);
> + if (ret && ret != -ENODEV)
> + return dev_err_probe(dev, ret, "failed to enable regulator\n");
> +
> + ret = regmap_read(regmap, KX022A_REG_WHO, &chip_id);
> + if (ret)
> + return dev_err_probe(dev, ret, "Failed to access sensor\n");
> +
> + if (chip_id != KX022A_ID) {
> + dev_err(dev, "unsupported device 0x%x\n", chip_id);
> + return -EINVAL;
> + }
> + fwnode = dev_fwnode(dev);
> + if (!fwnode)
> + return -ENODEV;
You can do it before allocating any of the resources, so it will bail out
earlier with less potential issues.
> + irq = fwnode_irq_get_byname(fwnode, "INT1");
> + if (irq > 0) {
> + data->inc_reg = KX022A_REG_INC1;
> + data->ien_reg = KX022A_REG_INC4;
> +
> + if (fwnode_irq_get_byname(fwnode, "INT2") > 0)
> + dev_warn(dev, "Only one IRQ supported\n");
> + } else {
> + irq = fwnode_irq_get_byname(fwnode, "INT2");
> + if (irq <= 0)
> + return dev_err_probe(dev, irq, "No suitable IRQ\n");
> +
> + data->inc_reg = KX022A_REG_INC5;
> + data->ien_reg = KX022A_REG_INC6;
> + }
> +
> + data->regmap = regmap;
> + data->dev = dev;
> + data->irq = irq;
> + data->odr_ns = KX022A_DEFAULT_PERIOD_NS;
> + mutex_init(&data->mutex);
> +
> + idev->channels = kx022a_channels;
> + idev->num_channels = ARRAY_SIZE(kx022a_channels);
> + idev->name = "kx022-accel";
> + idev->info = &kx022a_info;
> + idev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> + idev->available_scan_masks = kx022a_scan_masks;
> +
> + /* Read the mounting matrix, if present */
> + ret = iio_read_mount_matrix(dev, &data->orientation);
> + if (ret)
> + return ret;
> +
> + /* The sensor must be turned off for configuration */
> + ret = kx022a_turn_off_lock(data);
> + if (ret)
> + return ret;
> +
> + ret = kx022a_chip_init(data);
> + if (ret) {
> + mutex_unlock(&data->mutex);
> + return ret;
> + }
> +
> + ret = kx022a_turn_on_unlock(data);
> + if (ret)
> + return ret;
Probably a comment that tells why you need an atomic delay.
> + udelay(100);
> + ret = devm_iio_triggered_buffer_setup_ext(dev, idev,
> + &iio_pollfunc_store_time,
> + kx022a_trigger_handler,
> + IIO_BUFFER_DIRECTION_IN,
> + &kx022a_buffer_ops,
> + kx022a_fifo_attributes);
> +
> + if (ret)
> + return dev_err_probe(data->dev, ret,
> + "iio_triggered_buffer_setup_ext FAIL\n");
> + indio_trig = devm_iio_trigger_alloc(dev, "%sdata-rdy-dev%d", idev->name,
> + iio_device_id(idev));
> + if (!indio_trig)
> + return -ENOMEM;
> +
> + data->trig = indio_trig;
> +
> + indio_trig->ops = &kx022a_trigger_ops;
> + iio_trigger_set_drvdata(indio_trig, data);
> +
> + ret = devm_iio_trigger_register(dev, indio_trig);
> + if (ret)
> + return dev_err_probe(data->dev, ret,
> + "Trigger registration failed\n");
> +
> + ret = devm_iio_device_register(data->dev, idev);
> + if (ret < 0)
> + return dev_err_probe(dev, ret,
> + "Unable to register iio device\n");
> +
> + /*
> + * No need to check for NULL. request_threadedI_irq() defaults to
> + * dev_name() should the alloc fail.
> + */
> + name = devm_kasprintf(data->dev, GFP_KERNEL, "%s-kx022a",
> + dev_name(data->dev));
> +
> + ret = devm_request_threaded_irq(data->dev, irq, kx022a_irq_handler,
> + &kx022a_irq_thread_handler,
> + IRQF_ONESHOT, name, idev);
> + if (ret)
> + return dev_err_probe(data->dev, ret, "Could not request IRQ\n");
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_NS_GPL(kx022a_probe_internal, KIONIX_ACCEL);
> +
> +MODULE_DESCRIPTION("ROHM/Kionix KX022A accelerometer driver");
> +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> diff --git a/drivers/iio/accel/kionix-kx022a.h b/drivers/iio/accel/kionix-kx022a.h
> new file mode 100644
> index 000000000000..12424649d438
> --- /dev/null
> +++ b/drivers/iio/accel/kionix-kx022a.h
> @@ -0,0 +1,82 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (C) 2022 ROHM Semiconductors
> + *
> + * ROHM/KIONIX KX022A accelerometer driver
> + */
> +
> +#ifndef _KX022A_H_
> +#define _KX022A_H_
> +
> +#include <linux/bits.h>
> +#include <linux/regmap.h>
> +
> +#define KX022A_REG_WHO 0x0f
> +#define KX022A_ID 0xc8
> +
> +#define KX022A_REG_CNTL2 0x19
> +#define KX022A_MASK_SRST BIT(7)
> +#define KX022A_REG_CNTL 0x18
> +#define KX022A_MASK_PC1 BIT(7)
> +#define KX022A_MASK_RES BIT(6)
> +#define KX022A_MASK_DRDY BIT(5)
> +#define KX022A_MASK_GSEL GENMASK(4, 3)
> +#define KX022A_GSEL_SHIFT 3
> +#define KX022A_GSEL_2 0x0
> +#define KX022A_GSEL_4 BIT(3)
> +#define KX022A_GSEL_8 BIT(4)
> +#define KX022A_GSEL_16 GENMASK(4, 3)
> +
> +#define KX022A_REG_INS2 0x13
> +#define KX022A_MASK_INS2_DRDY BIT(4)
> +#define KX122_MASK_INS2_WMI BIT(5)
> +
> +#define KX022A_REG_XHP_L 0x0
> +#define KX022A_REG_XOUT_L 0x06
> +#define KX022A_REG_YOUT_L 0x08
> +#define KX022A_REG_ZOUT_L 0x0a
> +#define KX022A_REG_COTR 0x0c
> +#define KX022A_REG_TSCP 0x10
> +#define KX022A_REG_INT_REL 0x17
> +
> +#define KX022A_REG_ODCNTL 0x1b
> +
> +#define KX022A_REG_BTS_WUF_TH 0x31
> +#define KX022A_REG_MAN_WAKE 0x2c
> +
> +#define KX022A_REG_BUF_CNTL1 0x3a
> +#define KX022A_MASK_WM_TH GENMASK(6, 0)
> +#define KX022A_REG_BUF_CNTL2 0x3b
> +#define KX022A_MASK_BUF_EN BIT(7)
> +#define KX022A_MASK_BRES16 BIT(6)
> +#define KX022A_REG_BUF_STATUS_1 0x3c
> +#define KX022A_REG_BUF_STATUS_2 0x3d
> +#define KX022A_REG_BUF_CLEAR 0x3e
> +#define KX022A_REG_BUF_READ 0x3f
> +#define KX022A_MASK_ODR GENMASK(3, 0)
> +#define KX022A_ODR_SHIFT 3
> +#define KX022A_FIFO_MAX_WMI_TH 41
> +
> +#define KX022A_REG_INC1 0x1c
> +#define KX022A_REG_INC5 0x20
> +#define KX022A_REG_INC6 0x21
> +#define KX022A_MASK_IEN BIT(5)
> +#define KX022A_MASK_IPOL BIT(4)
> +#define KX022A_IPOL_LOW 0
> +#define KX022A_IPOL_HIGH KX022A_MASK_IPOL1
> +#define KX022A_MASK_ITYP BIT(3)
> +#define KX022A_ITYP_PULSE KX022A_MASK_ITYP
> +#define KX022A_ITYP_LEVEL 0
> +
> +#define KX022A_REG_INC4 0x1f
> +#define KX022A_MASK_WMI BIT(5)
> +
> +#define KX022A_REG_SELF_TEST 0x60
> +#define KX022A_MAX_REGISTER 0x60
> +
> +struct device;
> +
> +int kx022a_probe_internal(struct device *dev);
> +extern const struct regmap_config kx022a_regmap;
> +
> +#endif
> --
> 2.37.3
--
With Best Regards,
Andy Shevchenko