569 строки
14 KiB
C
569 строки
14 KiB
C
/**
|
|
* Sensortek STK8BA50 3-Axis Accelerometer
|
|
*
|
|
* Copyright (c) 2015, Intel Corporation.
|
|
*
|
|
* This file is subject to the terms and conditions of version 2 of
|
|
* the GNU General Public License. See the file COPYING in the main
|
|
* directory of this archive for more details.
|
|
*
|
|
* STK8BA50 7-bit I2C address: 0x18.
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/iio/buffer.h>
|
|
#include <linux/iio/iio.h>
|
|
#include <linux/iio/sysfs.h>
|
|
#include <linux/iio/trigger.h>
|
|
#include <linux/iio/triggered_buffer.h>
|
|
#include <linux/iio/trigger_consumer.h>
|
|
|
|
#define STK8BA50_REG_XOUT 0x02
|
|
#define STK8BA50_REG_YOUT 0x04
|
|
#define STK8BA50_REG_ZOUT 0x06
|
|
#define STK8BA50_REG_RANGE 0x0F
|
|
#define STK8BA50_REG_BWSEL 0x10
|
|
#define STK8BA50_REG_POWMODE 0x11
|
|
#define STK8BA50_REG_SWRST 0x14
|
|
#define STK8BA50_REG_INTEN2 0x17
|
|
#define STK8BA50_REG_INTMAP2 0x1A
|
|
|
|
#define STK8BA50_MODE_NORMAL 0
|
|
#define STK8BA50_MODE_SUSPEND 1
|
|
#define STK8BA50_MODE_POWERBIT BIT(7)
|
|
#define STK8BA50_DATA_SHIFT 6
|
|
#define STK8BA50_RESET_CMD 0xB6
|
|
#define STK8BA50_SR_1792HZ_IDX 7
|
|
#define STK8BA50_DREADY_INT_MASK 0x10
|
|
#define STK8BA50_DREADY_INT_MAP 0x81
|
|
#define STK8BA50_ALL_CHANNEL_MASK 7
|
|
#define STK8BA50_ALL_CHANNEL_SIZE 6
|
|
|
|
#define STK8BA50_DRIVER_NAME "stk8ba50"
|
|
#define STK8BA50_IRQ_NAME "stk8ba50_event"
|
|
|
|
#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
|
|
|
|
/*
|
|
* The accelerometer has four measurement ranges:
|
|
* +/-2g; +/-4g; +/-8g; +/-16g
|
|
*
|
|
* Acceleration values are 10-bit, 2's complement.
|
|
* Scales are calculated as following:
|
|
*
|
|
* scale1 = (2 + 2) * 9.81 / (2^10 - 1) = 0.0384
|
|
* scale2 = (4 + 4) * 9.81 / (2^10 - 1) = 0.0767
|
|
* etc.
|
|
*
|
|
* Scales are stored in this format:
|
|
* { <register value>, <scale value> }
|
|
*
|
|
* Locally, the range is stored as a table index.
|
|
*/
|
|
static const struct {
|
|
u8 reg_val;
|
|
u32 scale_val;
|
|
} stk8ba50_scale_table[] = {
|
|
{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
|
|
};
|
|
|
|
/* Sample rates are stored as { <register value>, <Hz value> } */
|
|
static const struct {
|
|
u8 reg_val;
|
|
u16 samp_freq;
|
|
} stk8ba50_samp_freq_table[] = {
|
|
{0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
|
|
{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
|
|
};
|
|
|
|
/* Used to map scan mask bits to their corresponding channel register. */
|
|
static const int stk8ba50_channel_table[] = {
|
|
STK8BA50_REG_XOUT,
|
|
STK8BA50_REG_YOUT,
|
|
STK8BA50_REG_ZOUT
|
|
};
|
|
|
|
struct stk8ba50_data {
|
|
struct i2c_client *client;
|
|
struct mutex lock;
|
|
int range;
|
|
u8 sample_rate_idx;
|
|
struct iio_trigger *dready_trig;
|
|
bool dready_trigger_on;
|
|
/*
|
|
* 3 x 16-bit channels (10-bit data, 6-bit padding) +
|
|
* 1 x 16 padding +
|
|
* 4 x 16 64-bit timestamp
|
|
*/
|
|
s16 buffer[8];
|
|
};
|
|
|
|
#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
|
|
.type = IIO_ACCEL, \
|
|
.address = reg, \
|
|
.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), \
|
|
.scan_index = index, \
|
|
.scan_type = { \
|
|
.sign = 's', \
|
|
.realbits = 10, \
|
|
.storagebits = 16, \
|
|
.shift = STK8BA50_DATA_SHIFT, \
|
|
.endianness = IIO_CPU, \
|
|
}, \
|
|
}
|
|
|
|
static const struct iio_chan_spec stk8ba50_channels[] = {
|
|
STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
|
|
STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
|
|
STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
|
|
IIO_CHAN_SOFT_TIMESTAMP(3),
|
|
};
|
|
|
|
static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
|
|
|
|
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
|
|
|
|
static struct attribute *stk8ba50_attributes[] = {
|
|
&iio_const_attr_in_accel_scale_available.dev_attr.attr,
|
|
&iio_const_attr_sampling_frequency_available.dev_attr.attr,
|
|
NULL,
|
|
};
|
|
|
|
static const struct attribute_group stk8ba50_attribute_group = {
|
|
.attrs = stk8ba50_attributes
|
|
};
|
|
|
|
static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
|
|
{
|
|
int ret;
|
|
struct i2c_client *client = data->client;
|
|
|
|
ret = i2c_smbus_read_word_data(client, reg);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "register read failed\n");
|
|
return ret;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
|
|
bool state)
|
|
{
|
|
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
if (state)
|
|
ret = i2c_smbus_write_byte_data(data->client,
|
|
STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
|
|
else
|
|
ret = i2c_smbus_write_byte_data(data->client,
|
|
STK8BA50_REG_INTEN2, 0x00);
|
|
|
|
if (ret < 0)
|
|
dev_err(&data->client->dev, "failed to set trigger state\n");
|
|
else
|
|
data->dready_trigger_on = state;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct iio_trigger_ops stk8ba50_trigger_ops = {
|
|
.set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
|
|
};
|
|
|
|
static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
|
|
{
|
|
int ret;
|
|
u8 masked_reg;
|
|
struct i2c_client *client = data->client;
|
|
|
|
ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
|
|
if (ret < 0)
|
|
goto exit_err;
|
|
|
|
if (mode)
|
|
masked_reg = ret | STK8BA50_MODE_POWERBIT;
|
|
else
|
|
masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
|
|
|
|
ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
|
|
masked_reg);
|
|
if (ret < 0)
|
|
goto exit_err;
|
|
|
|
return ret;
|
|
|
|
exit_err:
|
|
dev_err(&client->dev, "failed to change sensor mode\n");
|
|
return ret;
|
|
}
|
|
|
|
static int stk8ba50_read_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int *val, int *val2, long mask)
|
|
{
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
int ret;
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_RAW:
|
|
if (iio_buffer_enabled(indio_dev))
|
|
return -EBUSY;
|
|
mutex_lock(&data->lock);
|
|
ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
|
|
if (ret < 0) {
|
|
mutex_unlock(&data->lock);
|
|
return -EINVAL;
|
|
}
|
|
ret = stk8ba50_read_accel(data, chan->address);
|
|
if (ret < 0) {
|
|
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
mutex_unlock(&data->lock);
|
|
return -EINVAL;
|
|
}
|
|
*val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
|
|
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
mutex_unlock(&data->lock);
|
|
return IIO_VAL_INT;
|
|
case IIO_CHAN_INFO_SCALE:
|
|
*val = 0;
|
|
*val2 = stk8ba50_scale_table[data->range].scale_val;
|
|
return IIO_VAL_INT_PLUS_MICRO;
|
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
|
*val = stk8ba50_samp_freq_table
|
|
[data->sample_rate_idx].samp_freq;
|
|
*val2 = 0;
|
|
return IIO_VAL_INT;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static int stk8ba50_write_raw(struct iio_dev *indio_dev,
|
|
struct iio_chan_spec const *chan,
|
|
int val, int val2, long mask)
|
|
{
|
|
int ret;
|
|
int i;
|
|
int index = -1;
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
|
|
switch (mask) {
|
|
case IIO_CHAN_INFO_SCALE:
|
|
if (val != 0)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
|
|
if (val2 == stk8ba50_scale_table[i].scale_val) {
|
|
index = i;
|
|
break;
|
|
}
|
|
if (index < 0)
|
|
return -EINVAL;
|
|
|
|
ret = i2c_smbus_write_byte_data(data->client,
|
|
STK8BA50_REG_RANGE,
|
|
stk8ba50_scale_table[index].reg_val);
|
|
if (ret < 0)
|
|
dev_err(&data->client->dev,
|
|
"failed to set measurement range\n");
|
|
else
|
|
data->range = index;
|
|
|
|
return ret;
|
|
case IIO_CHAN_INFO_SAMP_FREQ:
|
|
for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
|
|
if (val == stk8ba50_samp_freq_table[i].samp_freq) {
|
|
index = i;
|
|
break;
|
|
}
|
|
if (index < 0)
|
|
return -EINVAL;
|
|
|
|
ret = i2c_smbus_write_byte_data(data->client,
|
|
STK8BA50_REG_BWSEL,
|
|
stk8ba50_samp_freq_table[index].reg_val);
|
|
if (ret < 0)
|
|
dev_err(&data->client->dev,
|
|
"failed to set sampling rate\n");
|
|
else
|
|
data->sample_rate_idx = index;
|
|
|
|
return ret;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static const struct iio_info stk8ba50_info = {
|
|
.read_raw = stk8ba50_read_raw,
|
|
.write_raw = stk8ba50_write_raw,
|
|
.attrs = &stk8ba50_attribute_group,
|
|
};
|
|
|
|
static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
|
|
{
|
|
struct iio_poll_func *pf = p;
|
|
struct iio_dev *indio_dev = pf->indio_dev;
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
int bit, ret, i = 0;
|
|
|
|
mutex_lock(&data->lock);
|
|
/*
|
|
* Do a bulk read if all channels are requested,
|
|
* from 0x02 (XOUT1) to 0x07 (ZOUT2)
|
|
*/
|
|
if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
|
|
ret = i2c_smbus_read_i2c_block_data(data->client,
|
|
STK8BA50_REG_XOUT,
|
|
STK8BA50_ALL_CHANNEL_SIZE,
|
|
(u8 *)data->buffer);
|
|
if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
|
|
dev_err(&data->client->dev, "register read failed\n");
|
|
goto err;
|
|
}
|
|
} else {
|
|
for_each_set_bit(bit, indio_dev->active_scan_mask,
|
|
indio_dev->masklength) {
|
|
ret = stk8ba50_read_accel(data,
|
|
stk8ba50_channel_table[bit]);
|
|
if (ret < 0)
|
|
goto err;
|
|
|
|
data->buffer[i++] = ret;
|
|
}
|
|
}
|
|
iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
|
|
pf->timestamp);
|
|
err:
|
|
mutex_unlock(&data->lock);
|
|
iio_trigger_notify_done(indio_dev->trig);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
|
|
{
|
|
struct iio_dev *indio_dev = private;
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
|
|
if (data->dready_trigger_on)
|
|
iio_trigger_poll(data->dready_trig);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
|
|
{
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
|
|
}
|
|
|
|
static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
|
|
{
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
}
|
|
|
|
static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
|
|
.preenable = stk8ba50_buffer_preenable,
|
|
.postenable = iio_triggered_buffer_postenable,
|
|
.predisable = iio_triggered_buffer_predisable,
|
|
.postdisable = stk8ba50_buffer_postdisable,
|
|
};
|
|
|
|
static int stk8ba50_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
int ret;
|
|
struct iio_dev *indio_dev;
|
|
struct stk8ba50_data *data;
|
|
|
|
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
|
|
if (!indio_dev) {
|
|
dev_err(&client->dev, "iio allocation failed!\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
data = iio_priv(indio_dev);
|
|
data->client = client;
|
|
i2c_set_clientdata(client, indio_dev);
|
|
mutex_init(&data->lock);
|
|
|
|
indio_dev->dev.parent = &client->dev;
|
|
indio_dev->info = &stk8ba50_info;
|
|
indio_dev->name = STK8BA50_DRIVER_NAME;
|
|
indio_dev->modes = INDIO_DIRECT_MODE;
|
|
indio_dev->channels = stk8ba50_channels;
|
|
indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
|
|
|
|
/* Reset all registers on startup */
|
|
ret = i2c_smbus_write_byte_data(client,
|
|
STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "failed to reset sensor\n");
|
|
goto err_power_off;
|
|
}
|
|
|
|
/* The default range is +/-2g */
|
|
data->range = 0;
|
|
|
|
/* The default sampling rate is 1792 Hz (maximum) */
|
|
data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
|
|
|
|
/* Set up interrupts */
|
|
ret = i2c_smbus_write_byte_data(client,
|
|
STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "failed to set up interrupts\n");
|
|
goto err_power_off;
|
|
}
|
|
ret = i2c_smbus_write_byte_data(client,
|
|
STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "failed to set up interrupts\n");
|
|
goto err_power_off;
|
|
}
|
|
|
|
if (client->irq > 0) {
|
|
ret = devm_request_threaded_irq(&client->dev, client->irq,
|
|
stk8ba50_data_rdy_trig_poll,
|
|
NULL,
|
|
IRQF_TRIGGER_RISING |
|
|
IRQF_ONESHOT,
|
|
STK8BA50_IRQ_NAME,
|
|
indio_dev);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "request irq %d failed\n",
|
|
client->irq);
|
|
goto err_power_off;
|
|
}
|
|
|
|
data->dready_trig = devm_iio_trigger_alloc(&client->dev,
|
|
"%s-dev%d",
|
|
indio_dev->name,
|
|
indio_dev->id);
|
|
if (!data->dready_trig) {
|
|
ret = -ENOMEM;
|
|
goto err_power_off;
|
|
}
|
|
|
|
data->dready_trig->dev.parent = &client->dev;
|
|
data->dready_trig->ops = &stk8ba50_trigger_ops;
|
|
iio_trigger_set_drvdata(data->dready_trig, indio_dev);
|
|
ret = iio_trigger_register(data->dready_trig);
|
|
if (ret) {
|
|
dev_err(&client->dev, "iio trigger register failed\n");
|
|
goto err_power_off;
|
|
}
|
|
}
|
|
|
|
ret = iio_triggered_buffer_setup(indio_dev,
|
|
iio_pollfunc_store_time,
|
|
stk8ba50_trigger_handler,
|
|
&stk8ba50_buffer_setup_ops);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "iio triggered buffer setup failed\n");
|
|
goto err_trigger_unregister;
|
|
}
|
|
|
|
ret = iio_device_register(indio_dev);
|
|
if (ret < 0) {
|
|
dev_err(&client->dev, "device_register failed\n");
|
|
goto err_buffer_cleanup;
|
|
}
|
|
|
|
return ret;
|
|
|
|
err_buffer_cleanup:
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
err_trigger_unregister:
|
|
if (data->dready_trig)
|
|
iio_trigger_unregister(data->dready_trig);
|
|
err_power_off:
|
|
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
return ret;
|
|
}
|
|
|
|
static int stk8ba50_remove(struct i2c_client *client)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct stk8ba50_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 stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int stk8ba50_suspend(struct device *dev)
|
|
{
|
|
struct stk8ba50_data *data;
|
|
|
|
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
}
|
|
|
|
static int stk8ba50_resume(struct device *dev)
|
|
{
|
|
struct stk8ba50_data *data;
|
|
|
|
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend, stk8ba50_resume);
|
|
|
|
#define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
|
|
#else
|
|
#define STK8BA50_PM_OPS NULL
|
|
#endif
|
|
|
|
static const struct i2c_device_id stk8ba50_i2c_id[] = {
|
|
{"stk8ba50", 0},
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
|
|
|
|
static const struct acpi_device_id stk8ba50_acpi_id[] = {
|
|
{"STK8BA50", 0},
|
|
{}
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
|
|
|
|
static struct i2c_driver stk8ba50_driver = {
|
|
.driver = {
|
|
.name = "stk8ba50",
|
|
.pm = STK8BA50_PM_OPS,
|
|
.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
|
|
},
|
|
.probe = stk8ba50_probe,
|
|
.remove = stk8ba50_remove,
|
|
.id_table = stk8ba50_i2c_id,
|
|
};
|
|
|
|
module_i2c_driver(stk8ba50_driver);
|
|
|
|
MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
|
|
MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
|
|
MODULE_LICENSE("GPL v2");
|