/*
* 3-axis accelerometer driver for MXC4005XC Memsic sensor
*
* Copyright (c) 2014, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/acpi.h>
#include <linux/regmap.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/trigger.h>
#include <linux/iio/buffer.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#define MXC4005_DRV_NAME "mxc4005"
#define MXC4005_IRQ_NAME "mxc4005_event"
#define MXC4005_REGMAP_NAME "mxc4005_regmap"
#define MXC4005_REG_XOUT_UPPER 0x03
#define MXC4005_REG_XOUT_LOWER 0x04
#define MXC4005_REG_YOUT_UPPER 0x05
#define MXC4005_REG_YOUT_LOWER 0x06
#define MXC4005_REG_ZOUT_UPPER 0x07
#define MXC4005_REG_ZOUT_LOWER 0x08
#define MXC4005_REG_INT_MASK1 0x0B
#define MXC4005_REG_INT_MASK1_BIT_DRDYE 0x01
#define MXC4005_REG_INT_CLR1 0x01
#define MXC4005_REG_INT_CLR1_BIT_DRDYC 0x01
#define MXC4005_REG_CONTROL 0x0D
#define MXC4005_REG_CONTROL_MASK_FSR GENMASK(6, 5)
#define MXC4005_CONTROL_FSR_SHIFT 5
#define MXC4005_REG_DEVICE_ID 0x0E
enum mxc4005_axis {
AXIS_X,
AXIS_Y,
AXIS_Z,
};
enum mxc4005_range {
MXC4005_RANGE_2G,
MXC4005_RANGE_4G,
MXC4005_RANGE_8G,
};
struct mxc4005_data {
struct device *dev;
struct mutex mutex;
struct regmap *regmap;
struct iio_trigger *dready_trig;
__be16 buffer[8];
bool trigger_enabled;
};
/*
* MXC4005 can operate in the following ranges:
* +/- 2G, 4G, 8G (the default +/-2G)
*
* (2 + 2) * 9.81 / (2^12 - 1) = 0.009582
* (4 + 4) * 9.81 / (2^12 - 1) = 0.019164
* (8 + 8) * 9.81 / (2^12 - 1) = 0.038329
*/
static const struct {
u8 range;
int scale;
} mxc4005_scale_table[] = {
{MXC4005_RANGE_2G, 9582},
{MXC4005_RANGE_4G, 19164},
{MXC4005_RANGE_8G, 38329},
};
static IIO_CONST_ATTR(in_accel_scale_available, "0.009582 0.019164 0.038329");
static struct attribute *mxc4005_attributes[] = {
&iio_const_attr_in_accel_scale_available.dev_attr.attr,
NULL,
};
static const struct attribute_group mxc4005_attrs_group = {
.attrs = mxc4005_attributes,
};
static bool mxc4005_is_readable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case MXC4005_REG_XOUT_UPPER:
case MXC4005_REG_XOUT_LOWER:
case MXC4005_REG_YOUT_UPPER:
case MXC4005_REG_YOUT_LOWER:
case MXC4005_REG_ZOUT_UPPER:
case MXC4005_REG_ZOUT_LOWER:
case MXC4005_REG_DEVICE_ID:
case MXC4005_REG_CONTROL:
return true;
default:
return false;
}
}
static bool mxc4005_is_writeable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case MXC4005_REG_INT_CLR1:
case MXC4005_REG_INT_MASK1:
case MXC4005_REG_CONTROL:
return true;
default:
return false;
}
}
static const struct regmap_config mxc4005_regmap_config = {
.name = MXC4005_REGMAP_NAME,
.reg_bits = 8,
.val_bits = 8,
.max_register = MXC4005_REG_DEVICE_ID,
.readable_reg = mxc4005_is_readable_reg,
.writeable_reg = mxc4005_is_writeable_reg,
};
static int mxc4005_read_xyz(struct mxc4005_data *data)
{
int ret;
ret = regmap_bulk_read(data->regmap, MXC4005_REG_XOUT_UPPER,
(u8 *) data->buffer, sizeof(data->buffer));
if (ret < 0) {
dev_err(data->dev, "failed to read axes\n");
return ret;
}
return 0;
}
static int mxc4005_read_axis(struct mxc4005_data *data,
unsigned int addr)
{
__be16 reg;
int ret;
ret = regmap_bulk_read(data->regmap, addr, (u8 *) ®, sizeof(reg));
if (ret < 0) {
dev_err(data->dev, "failed to read reg %02x\n", addr);
return ret;
}
return be16_to_cpu(reg);
}
static int mxc4005_read_scale(struct mxc4005_data *data)
{
unsigned int reg;
int ret;
int i;
ret = regmap_read(data->regmap, MXC4005_REG_CONTROL, ®);
if (ret < 0) {
dev_err(data->dev, "failed to read reg_control\n");
return ret;
}
i = reg >> MXC4005_CONTROL_FSR_SHIFT;
if (i < 0 || i >= ARRAY_SIZE(mxc4005_scale_table))
return -EINVAL;
return mxc4005_scale_table[i].scale;
}
static int mxc4005_set_scale(struct mxc4005_data *data, int val)
{
unsigned int reg;
int i;
int ret;
for (i = 0; i < ARRAY_SIZE(mxc4005_scale_table); i++) {
if (mxc4005_scale_table[i].scale == val) {
reg = i << MXC4005_CONTROL_FSR_SHIFT;
ret = regmap_update_bits(data->regmap,
MXC4005_REG_CONTROL,
MXC4005_REG_CONTROL_MASK_FSR,
reg);
if (ret < 0)
dev_err(data->dev,
"failed to write reg_control\n");
return ret;
}
}
return -EINVAL;
}
static int mxc4005_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct mxc4005_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_ACCEL:
if (iio_buffer_enabled(indio_dev))
return -EBUSY;
ret = mxc4005_read_axis(data, chan->address);
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:
ret = mxc4005_read_scale(data);
if (ret < 0)
return ret;
*val = 0;
*val2 = ret;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int mxc4005_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct mxc4005_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_SCALE:
if (val != 0)
return -EINVAL;
return mxc4005_set_scale(data, val2);
default:
return -EINVAL;
}
}
static const struct iio_info mxc4005_info = {
.driver_module = THIS_MODULE,
.read_raw = mxc4005_read_raw,
.write_raw = mxc4005_write_raw,
.attrs = &mxc4005_attrs_group,
};
static const unsigned long mxc4005_scan_masks[] = {
BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
0
};
#define MXC4005_CHANNEL(_axis, _addr) { \
.type = IIO_ACCEL, \
.modified = 1, \
.channel2 = IIO_MOD_##_axis, \
.address = _addr, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = AXIS_##_axis, \
.scan_type = { \
.sign = 's', \
.realbits = 12, \
.storagebits = 16, \
.shift = 4, \
.endianness = IIO_BE, \
}, \
}
static const struct iio_chan_spec mxc4005_channels[] = {
MXC4005_CHANNEL(X, MXC4005_REG_XOUT_UPPER),
MXC4005_CHANNEL(Y, MXC4005_REG_YOUT_UPPER),
MXC4005_CHANNEL(Z, MXC4005_REG_ZOUT_UPPER),
IIO_CHAN_SOFT_TIMESTAMP(3),
};
static irqreturn_t mxc4005_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = private;
struct iio_dev *indio_dev = pf->indio_dev;
struct mxc4005_data *data = iio_priv(indio_dev);
int ret;
ret = mxc4005_read_xyz(data);
if (ret < 0)
goto err;
iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
pf->timestamp);
err:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int mxc4005_clr_intr(struct mxc4005_data *data)
{
int ret;
/* clear interrupt */
ret = regmap_write(data->regmap, MXC4005_REG_INT_CLR1,
MXC4005_REG_INT_CLR1_BIT_DRDYC);
if (ret < 0) {
dev_err(data->dev, "failed to write to reg_int_clr1\n");
return ret;
}
return 0;
}
static int mxc4005_set_trigger_state(struct iio_trigger *trig,
bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mxc4005_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
if (state) {
ret = regmap_write(data->regmap, MXC4005_REG_INT_MASK1,
MXC4005_REG_INT_MASK1_BIT_DRDYE);
} else {
ret = regmap_write(data->regmap, MXC4005_REG_INT_MASK1,
~MXC4005_REG_INT_MASK1_BIT_DRDYE);
}
if (ret < 0) {
mutex_unlock(&data->mutex);
dev_err(data->dev, "failed to update reg_int_mask1");
return ret;
}
data->trigger_enabled = state;
mutex_unlock(&data->mutex);
return 0;
}
static int mxc4005_trigger_try_reen(struct iio_trigger *trig)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct mxc4005_data *data = iio_priv(indio_dev);
if (!data->dready_trig)
return 0;
return mxc4005_clr_intr(data);
}
static const struct iio_trigger_ops mxc4005_trigger_ops = {
.set_trigger_state = mxc4005_set_trigger_state,
.try_reenable = mxc4005_trigger_try_reen,
.owner = THIS_MODULE,
};
static int mxc4005_chip_init(struct mxc4005_data *data)
{
int ret;
unsigned int reg;
ret = regmap_read(data->regmap, MXC4005_REG_DEVICE_ID, ®);
if (ret < 0) {
dev_err(data->dev, "failed to read chip id\n");
return ret;
}
dev_dbg(data->dev, "MXC4005 chip id %02x\n", reg);
return 0;
}
static int mxc4005_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct mxc4005_data *data;
struct iio_dev *indio_dev;
struct regmap *regmap;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
regmap = devm_regmap_init_i2c(client, &mxc4005_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&client->dev, "failed to initialize regmap\n");
return PTR_ERR(regmap);
}
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->dev = &client->dev;
data->regmap = regmap;
ret = mxc4005_chip_init(data);
if (ret < 0) {
dev_err(&client->dev, "failed to initialize chip\n");
return ret;
}
mutex_init(&data->mutex);
indio_dev->dev.parent = &client->dev;
indio_dev->channels = mxc4005_channels;
indio_dev->num_channels = ARRAY_SIZE(mxc4005_channels);
indio_dev->available_scan_masks = mxc4005_scan_masks;
indio_dev->name = MXC4005_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &mxc4005_info;
ret = iio_triggered_buffer_setup(indio_dev,
iio_pollfunc_store_time,
mxc4005_trigger_handler,
NULL);
if (ret < 0) {
dev_err(&client->dev,
"failed to setup iio triggered buffer\n");
return ret;
}
if (client->irq > 0) {
data->dready_trig = devm_iio_trigger_alloc(&client->dev,
"%s-dev%d",
indio_dev->name,
indio_dev->id);
if (!data->dready_trig)
return -ENOMEM;
ret = devm_request_threaded_irq(&client->dev, client->irq,
iio_trigger_generic_data_rdy_poll,
NULL,
IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
MXC4005_IRQ_NAME,
data->dready_trig);
if (ret) {
dev_err(&client->dev,
"failed to init threaded irq\n");
goto err_buffer_cleanup;
}
data->dready_trig->dev.parent = &client->dev;
data->dready_trig->ops = &mxc4005_trigger_ops;
iio_trigger_set_drvdata(data->dready_trig, indio_dev);
indio_dev->trig = data->dready_trig;
iio_trigger_get(indio_dev->trig);
ret = iio_trigger_register(data->dready_trig);
if (ret) {
dev_err(&client->dev,
"failed to register trigger\n");
goto err_trigger_unregister;
}
}
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev,
"unable to register iio device %d\n", ret);
goto err_buffer_cleanup;
}
return 0;
err_trigger_unregister:
iio_trigger_unregister(data->dready_trig);
err_buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
return ret;
}
static int mxc4005_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct mxc4005_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
if (data->dready_trig)
iio_trigger_unregister(data->dready_trig);
return 0;
}
static const struct acpi_device_id mxc4005_acpi_match[] = {
{"MXC4005", 0},
{ },
};
MODULE_DEVICE_TABLE(acpi, mxc4005_acpi_match);
static const struct i2c_device_id mxc4005_id[] = {
{"mxc4005", 0},
{ },
};
MODULE_DEVICE_TABLE(i2c, mxc4005_id);
static struct i2c_driver mxc4005_driver = {
.driver = {
.name = MXC4005_DRV_NAME,
.acpi_match_table = ACPI_PTR(mxc4005_acpi_match),
},
.probe = mxc4005_probe,
.remove = mxc4005_remove,
.id_table = mxc4005_id,
};
module_i2c_driver(mxc4005_driver);
MODULE_AUTHOR("Teodora Baluta <teodora.baluta@intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MXC4005 3-axis accelerometer driver");
