// SPDX-License-Identifier: GPL-2.0-only
/*
* kxsd9.c simple support for the Kionix KXSD9 3D
* accelerometer.
*
* Copyright (c) 2008-2009 Jonathan Cameron <[email protected]>
*
* The i2c interface is very similar, so shouldn't be a problem once
* I have a suitable wire made up.
*
* TODO: Support the motion detector
*/
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/sysfs.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/regulator/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include "kxsd9.h"
#define KXSD9_REG_X 0x00
#define KXSD9_REG_Y 0x02
#define KXSD9_REG_Z 0x04
#define KXSD9_REG_AUX 0x06
#define KXSD9_REG_RESET 0x0a
#define KXSD9_REG_CTRL_C 0x0c
#define KXSD9_CTRL_C_FS_MASK 0x03
#define KXSD9_CTRL_C_FS_8G 0x00
#define KXSD9_CTRL_C_FS_6G 0x01
#define KXSD9_CTRL_C_FS_4G 0x02
#define KXSD9_CTRL_C_FS_2G 0x03
#define KXSD9_CTRL_C_MOT_LAT BIT(3)
#define KXSD9_CTRL_C_MOT_LEV BIT(4)
#define KXSD9_CTRL_C_LP_MASK 0xe0
#define KXSD9_CTRL_C_LP_NONE 0x00
#define KXSD9_CTRL_C_LP_2000HZC BIT(5)
#define KXSD9_CTRL_C_LP_2000HZB BIT(6)
#define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6))
#define KXSD9_CTRL_C_LP_1000HZ BIT(7)
#define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5))
#define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6))
#define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5))
#define KXSD9_REG_CTRL_B 0x0d
#define KXSD9_CTRL_B_CLK_HLD BIT(7)
#define KXSD9_CTRL_B_ENABLE BIT(6)
#define KXSD9_CTRL_B_ST BIT(5) /* Self-test */
#define KXSD9_REG_CTRL_A 0x0e
/**
* struct kxsd9_state - device related storage
* @dev: pointer to the parent device
* @map: regmap to the device
* @orientation: mounting matrix, flipped axis etc
* @regs: regulators for this device, VDD and IOVDD
* @scale: the current scaling setting
*/
struct kxsd9_state {
struct device *dev;
struct regmap *map;
struct iio_mount_matrix orientation;
struct regulator_bulk_data regs[2];
u8 scale;
};
#define KXSD9_SCALE_2G "0.011978"
#define KXSD9_SCALE_4G "0.023927"
#define KXSD9_SCALE_6G "0.035934"
#define KXSD9_SCALE_8G "0.047853"
/* reverse order */
static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 };
#define KXSD9_ZERO_G_OFFSET -2048
/*
* Regulator names
*/
static const char kxsd9_reg_vdd[] = "vdd";
static const char kxsd9_reg_iovdd[] = "iovdd";
static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro)
{
int ret, i;
struct kxsd9_state *st = iio_priv(indio_dev);
bool foundit = false;
for (i = 0; i < 4; i++)
if (micro == kxsd9_micro_scales[i]) {
foundit = true;
break;
}
if (!foundit)
return -EINVAL;
ret = regmap_update_bits(st->map,
KXSD9_REG_CTRL_C,
KXSD9_CTRL_C_FS_MASK,
i);
if (ret < 0)
goto error_ret;
/* Cached scale when the sensor is powered down */
st->scale = i;
error_ret:
return ret;
}
static IIO_CONST_ATTR(accel_scale_available,
KXSD9_SCALE_2G " "
KXSD9_SCALE_4G " "
KXSD9_SCALE_6G " "
KXSD9_SCALE_8G);
static struct attribute *kxsd9_attributes[] = {
&iio_const_attr_accel_scale_available.dev_attr.attr,
NULL,
};
static int kxsd9_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long mask)
{
int ret = -EINVAL;
struct kxsd9_state *st = iio_priv(indio_dev);
pm_runtime_get_sync(st->dev);
if (mask == IIO_CHAN_INFO_SCALE) {
/* Check no integer component */
if (val)
return -EINVAL;
ret = kxsd9_write_scale(indio_dev, val2);
}
pm_runtime_mark_last_busy(st->dev);
pm_runtime_put_autosuspend(st->dev);
return ret;
}
static int kxsd9_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret = -EINVAL;
struct kxsd9_state *st = iio_priv(indio_dev);
unsigned int regval;
__be16 raw_val;
u16 nval;
pm_runtime_get_sync(st->dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = regmap_bulk_read(st->map, chan->address, &raw_val,
sizeof(raw_val));
if (ret)
goto error_ret;
nval = be16_to_cpu(raw_val);
/* Only 12 bits are valid */
nval >>= 4;
*val = nval;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_OFFSET:
/* This has a bias of -2048 */
*val = KXSD9_ZERO_G_OFFSET;
ret = IIO_VAL_INT;
break;
case IIO_CHAN_INFO_SCALE:
ret = regmap_read(st->map,
KXSD9_REG_CTRL_C,
®val);
if (ret < 0)
goto error_ret;
*val = 0;
*val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK];
ret = IIO_VAL_INT_PLUS_MICRO;
break;
}
error_ret:
pm_runtime_mark_last_busy(st->dev);
pm_runtime_put_autosuspend(st->dev);
return ret;
};
static irqreturn_t kxsd9_trigger_handler(int irq, void *p)
{
const struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct kxsd9_state *st = iio_priv(indio_dev);
/*
* Ensure correct positioning and alignment of timestamp.
* No need to zero initialize as all elements written.
*/
struct {
__be16 chan[4];
s64 ts __aligned(8);
} hw_values;
int ret;
ret = regmap_bulk_read(st->map,
KXSD9_REG_X,
hw_values.chan,
sizeof(hw_values.chan));
if (ret) {
dev_err(st->dev, "error reading data: %d\n", ret);
goto out;
}
iio_push_to_buffers_with_timestamp(indio_dev,
&hw_values,
iio_get_time_ns(indio_dev));
out:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int kxsd9_buffer_preenable(struct iio_dev *indio_dev)
{
struct kxsd9_state *st = iio_priv(indio_dev);
pm_runtime_get_sync(st->dev);
return 0;
}
static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev)
{
struct kxsd9_state *st = iio_priv(indio_dev);
pm_runtime_mark_last_busy(st->dev);
pm_runtime_put_autosuspend(st->dev);
return 0;
}
static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = {
.preenable = kxsd9_buffer_preenable,
.postdisable = kxsd9_buffer_postdisable,
};
static const struct iio_mount_matrix *
kxsd9_get_mount_matrix(const struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct kxsd9_state *st = iio_priv(indio_dev);
return &st->orientation;
}
static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = {
IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix),
{ },
};
#define KXSD9_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_OFFSET), \
.ext_info = kxsd9_ext_info, \
.address = KXSD9_REG_##axis, \
.scan_index = index, \
.scan_type = { \
.sign = 'u', \
.realbits = 12, \
.storagebits = 16, \
.shift = 4, \
.endianness = IIO_BE, \
}, \
}
static const struct iio_chan_spec kxsd9_channels[] = {
KXSD9_ACCEL_CHAN(X, 0),
KXSD9_ACCEL_CHAN(Y, 1),
KXSD9_ACCEL_CHAN(Z, 2),
{
.type = IIO_VOLTAGE,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.indexed = 1,
.address = KXSD9_REG_AUX,
.scan_index = 3,
.scan_type = {
.sign = 'u',
.realbits = 12,
.storagebits = 16,
.shift = 4,
.endianness = IIO_BE,
},
},
IIO_CHAN_SOFT_TIMESTAMP(4),
};
static const struct attribute_group kxsd9_attribute_group = {
.attrs = kxsd9_attributes,
};
static int kxsd9_power_up(struct kxsd9_state *st)
{
int ret;
/* Enable the regulators */
ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs);
if (ret) {
dev_err(st->dev, "Cannot enable regulators\n");
return ret;
}
/* Power up */
ret = regmap_write(st->map,
KXSD9_REG_CTRL_B,
KXSD9_CTRL_B_ENABLE);
if (ret)
return ret;
/*
* Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g,
* latched wakeup
*/
ret = regmap_write(st->map,
KXSD9_REG_CTRL_C,
KXSD9_CTRL_C_LP_1000HZ |
KXSD9_CTRL_C_MOT_LEV |
KXSD9_CTRL_C_MOT_LAT |
st->scale);
if (ret)
return ret;
/*
* Power-up time depends on the LPF setting, but typ 15.9 ms, let's
* set 20 ms to allow for some slack.
*/
msleep(20);
return 0;
};
static int kxsd9_power_down(struct kxsd9_state *st)
{
int ret;
/*
* Set into low power mode - since there may be more users of the
* regulators this is the first step of the power saving: it will
* make sure we conserve power even if there are others users on the
* regulators.
*/
ret = regmap_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE);
if (ret)
return ret;
/* Disable the regulators */
ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs);
if (ret) {
dev_err(st->dev, "Cannot disable regulators\n");
return ret;
}
return 0;
}
static const struct iio_info kxsd9_info = {
.read_raw = &kxsd9_read_raw,
.write_raw = &kxsd9_write_raw,
.attrs = &kxsd9_attribute_group,
};
/* Four channels apart from timestamp, scan mask = 0x0f */
static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 };
int kxsd9_common_probe(struct device *dev,
struct regmap *map,
const char *name)
{
struct iio_dev *indio_dev;
struct kxsd9_state *st;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
st = iio_priv(indio_dev);
st->dev = dev;
st->map = map;
indio_dev->channels = kxsd9_channels;
indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels);
indio_dev->name = name;
indio_dev->info = &kxsd9_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->available_scan_masks = kxsd9_scan_masks;
/* Read the mounting matrix, if present */
ret = iio_read_mount_matrix(dev, &st->orientation);
if (ret)
return ret;
/* Fetch and turn on regulators */
st->regs[0].supply = kxsd9_reg_vdd;
st->regs[1].supply = kxsd9_reg_iovdd;
ret = devm_regulator_bulk_get(dev,
ARRAY_SIZE(st->regs),
st->regs);
if (ret) {
dev_err(dev, "Cannot get regulators\n");
return ret;
}
/* Default scaling */
st->scale = KXSD9_CTRL_C_FS_2G;
kxsd9_power_up(st);
ret = iio_triggered_buffer_setup(indio_dev,
iio_pollfunc_store_time,
kxsd9_trigger_handler,
&kxsd9_buffer_setup_ops);
if (ret) {
dev_err(dev, "triggered buffer setup failed\n");
goto err_power_down;
}
ret = iio_device_register(indio_dev);
if (ret)
goto err_cleanup_buffer;
dev_set_drvdata(dev, indio_dev);
/* Enable runtime PM */
pm_runtime_get_noresume(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
/*
* Set autosuspend to two orders of magnitude larger than the
* start-up time. 20ms start-up time means 2000ms autosuspend,
* i.e. 2 seconds.
*/
pm_runtime_set_autosuspend_delay(dev, 2000);
pm_runtime_use_autosuspend(dev);
pm_runtime_put(dev);
return 0;
err_cleanup_buffer:
iio_triggered_buffer_cleanup(indio_dev);
err_power_down:
kxsd9_power_down(st);
return ret;
}
EXPORT_SYMBOL_NS(kxsd9_common_probe, IIO_KXSD9);
void kxsd9_common_remove(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct kxsd9_state *st = iio_priv(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
iio_device_unregister(indio_dev);
pm_runtime_get_sync(dev);
pm_runtime_put_noidle(dev);
pm_runtime_disable(dev);
kxsd9_power_down(st);
}
EXPORT_SYMBOL_NS(kxsd9_common_remove, IIO_KXSD9);
static int kxsd9_runtime_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct kxsd9_state *st = iio_priv(indio_dev);
return kxsd9_power_down(st);
}
static int kxsd9_runtime_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct kxsd9_state *st = iio_priv(indio_dev);
return kxsd9_power_up(st);
}
EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend,
kxsd9_runtime_resume, NULL, IIO_KXSD9);
MODULE_AUTHOR("Jonathan Cameron <[email protected]>");
MODULE_DESCRIPTION("Kionix KXSD9 driver");
MODULE_LICENSE("GPL v2");
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