linux/drivers/iio/accel/bma180.c

677 lines
16 KiB
C

/*
* bma180.c - IIO driver for Bosch BMA180 triaxial acceleration sensor
*
* Copyright 2013 Oleksandr Kravchenko <x0199363@ti.com>
*
* 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.
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/buffer.h>
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
#define BMA180_DRV_NAME "bma180"
#define BMA180_IRQ_NAME "bma180_event"
/* Register set */
#define BMA180_CHIP_ID 0x00 /* Need to distinguish BMA180 from other */
#define BMA180_ACC_X_LSB 0x02 /* First of 6 registers of accel data */
#define BMA180_CTRL_REG0 0x0d
#define BMA180_RESET 0x10
#define BMA180_BW_TCS 0x20
#define BMA180_CTRL_REG3 0x21
#define BMA180_TCO_Z 0x30
#define BMA180_OFFSET_LSB1 0x35
/* BMA180_CTRL_REG0 bits */
#define BMA180_DIS_WAKE_UP BIT(0) /* Disable wake up mode */
#define BMA180_SLEEP BIT(1) /* 1 - chip will sleep */
#define BMA180_EE_W BIT(4) /* Unlock writing to addr from 0x20 */
#define BMA180_RESET_INT BIT(6) /* Reset pending interrupts */
/* BMA180_CTRL_REG3 bits */
#define BMA180_NEW_DATA_INT BIT(1) /* Intr every new accel data is ready */
/* BMA180_OFFSET_LSB1 skipping mode bit */
#define BMA180_SMP_SKIP BIT(0)
/* Bit masks for registers bit fields */
#define BMA180_RANGE 0x0e /* Range of measured accel values*/
#define BMA180_BW 0xf0 /* Accel bandwidth */
#define BMA180_MODE_CONFIG 0x03 /* Config operation modes */
/* We have to write this value in reset register to do soft reset */
#define BMA180_RESET_VAL 0xb6
#define BMA_180_ID_REG_VAL 0x03
/* Chip power modes */
#define BMA180_LOW_NOISE 0x00
#define BMA180_LOW_POWER 0x03
#define BMA180_LOW_NOISE_STR "low_noise"
#define BMA180_LOW_POWER_STR "low_power"
/* Defaults values */
#define BMA180_DEF_PMODE 0
#define BMA180_DEF_BW 20
#define BMA180_DEF_SCALE 250
/* Available values for sysfs */
#define BMA180_FLP_FREQ_AVAILABLE \
"10 20 40 75 150 300"
#define BMA180_SCALE_AVAILABLE \
"0.000130 0.000190 0.000250 0.000380 0.000500 0.000990 0.001980"
struct bma180_data {
struct i2c_client *client;
struct iio_trigger *trig;
struct mutex mutex;
int sleep_state;
int scale;
int bw;
int pmode;
char *buff;
};
enum bma180_axis {
AXIS_X,
AXIS_Y,
AXIS_Z,
};
static int bw_table[] = { 10, 20, 40, 75, 150, 300 }; /* Hz */
static int scale_table[] = { 130, 190, 250, 380, 500, 990, 1980 };
static int bma180_get_acc_reg(struct bma180_data *data, enum bma180_axis axis)
{
u8 reg = BMA180_ACC_X_LSB + axis * 2;
int ret;
if (data->sleep_state)
return -EBUSY;
ret = i2c_smbus_read_word_data(data->client, reg);
if (ret < 0)
dev_err(&data->client->dev,
"failed to read accel_%c registers\n", 'x' + axis);
return ret;
}
static int bma180_set_bits(struct bma180_data *data, u8 reg, u8 mask, u8 val)
{
int ret = i2c_smbus_read_byte_data(data->client, reg);
u8 reg_val = (ret & ~mask) | (val << (ffs(mask) - 1));
if (ret < 0)
return ret;
return i2c_smbus_write_byte_data(data->client, reg, reg_val);
}
static int bma180_reset_intr(struct bma180_data *data)
{
int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_RESET_INT, 1);
if (ret)
dev_err(&data->client->dev, "failed to reset interrupt\n");
return ret;
}
static int bma180_set_new_data_intr_state(struct bma180_data *data, int state)
{
u8 reg_val = state ? BMA180_NEW_DATA_INT : 0x00;
int ret = i2c_smbus_write_byte_data(data->client, BMA180_CTRL_REG3,
reg_val);
if (ret)
goto err;
ret = bma180_reset_intr(data);
if (ret)
goto err;
return 0;
err:
dev_err(&data->client->dev,
"failed to set new data interrupt state %d\n", state);
return ret;
}
static int bma180_set_sleep_state(struct bma180_data *data, int state)
{
int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_SLEEP, state);
if (ret) {
dev_err(&data->client->dev,
"failed to set sleep state %d\n", state);
return ret;
}
data->sleep_state = state;
return 0;
}
static int bma180_set_ee_writing_state(struct bma180_data *data, int state)
{
int ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_EE_W, state);
if (ret)
dev_err(&data->client->dev,
"failed to set ee writing state %d\n", state);
return ret;
}
static int bma180_set_bw(struct bma180_data *data, int val)
{
int ret, i;
if (data->sleep_state)
return -EBUSY;
for (i = 0; i < ARRAY_SIZE(bw_table); ++i) {
if (bw_table[i] == val) {
ret = bma180_set_bits(data,
BMA180_BW_TCS, BMA180_BW, i);
if (ret) {
dev_err(&data->client->dev,
"failed to set bandwidth\n");
return ret;
}
data->bw = val;
return 0;
}
}
return -EINVAL;
}
static int bma180_set_scale(struct bma180_data *data, int val)
{
int ret, i;
if (data->sleep_state)
return -EBUSY;
for (i = 0; i < ARRAY_SIZE(scale_table); ++i)
if (scale_table[i] == val) {
ret = bma180_set_bits(data,
BMA180_OFFSET_LSB1, BMA180_RANGE, i);
if (ret) {
dev_err(&data->client->dev,
"failed to set scale\n");
return ret;
}
data->scale = val;
return 0;
}
return -EINVAL;
}
static int bma180_set_pmode(struct bma180_data *data, int mode)
{
u8 reg_val = mode ? BMA180_LOW_POWER : BMA180_LOW_NOISE;
int ret = bma180_set_bits(data, BMA180_TCO_Z, BMA180_MODE_CONFIG,
reg_val);
if (ret) {
dev_err(&data->client->dev, "failed to set power mode\n");
return ret;
}
data->pmode = mode;
return 0;
}
static int bma180_soft_reset(struct bma180_data *data)
{
int ret = i2c_smbus_write_byte_data(data->client,
BMA180_RESET, BMA180_RESET_VAL);
if (ret)
dev_err(&data->client->dev, "failed to reset the chip\n");
return ret;
}
static int bma180_chip_init(struct bma180_data *data)
{
/* Try to read chip_id register. It must return 0x03. */
int ret = i2c_smbus_read_byte_data(data->client, BMA180_CHIP_ID);
if (ret < 0)
goto err;
if (ret != BMA_180_ID_REG_VAL) {
ret = -ENODEV;
goto err;
}
ret = bma180_soft_reset(data);
if (ret)
goto err;
/*
* No serial transaction should occur within minimum 10 us
* after soft_reset command
*/
msleep(20);
ret = bma180_set_bits(data, BMA180_CTRL_REG0, BMA180_DIS_WAKE_UP, 1);
if (ret)
goto err;
ret = bma180_set_ee_writing_state(data, 1);
if (ret)
goto err;
ret = bma180_set_new_data_intr_state(data, 0);
if (ret)
goto err;
ret = bma180_set_bits(data, BMA180_OFFSET_LSB1, BMA180_SMP_SKIP, 1);
if (ret)
goto err;
ret = bma180_set_pmode(data, BMA180_DEF_PMODE);
if (ret)
goto err;
ret = bma180_set_bw(data, BMA180_DEF_BW);
if (ret)
goto err;
ret = bma180_set_scale(data, BMA180_DEF_SCALE);
if (ret)
goto err;
return 0;
err:
dev_err(&data->client->dev, "failed to init the chip\n");
return ret;
}
static void bma180_chip_disable(struct bma180_data *data)
{
if (bma180_set_new_data_intr_state(data, 0))
goto err;
if (bma180_set_ee_writing_state(data, 0))
goto err;
if (bma180_set_sleep_state(data, 1))
goto err;
return;
err:
dev_err(&data->client->dev, "failed to disable the chip\n");
}
static IIO_CONST_ATTR(in_accel_filter_low_pass_3db_frequency_available,
BMA180_FLP_FREQ_AVAILABLE);
static IIO_CONST_ATTR(in_accel_scale_available, BMA180_SCALE_AVAILABLE);
static struct attribute *bma180_attributes[] = {
&iio_const_attr_in_accel_filter_low_pass_3db_frequency_available.dev_attr.attr,
&iio_const_attr_in_accel_scale_available.dev_attr.attr,
NULL,
};
static const struct attribute_group bma180_attrs_group = {
.attrs = bma180_attributes,
};
static int bma180_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int *val, int *val2,
long mask)
{
struct bma180_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
mutex_lock(&data->mutex);
if (iio_buffer_enabled(indio_dev))
ret = -EBUSY;
else
ret = bma180_get_acc_reg(data, chan->scan_index);
mutex_unlock(&data->mutex);
if (ret < 0)
return ret;
*val = (s16)ret >> chan->scan_type.shift;
return IIO_VAL_INT;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
*val = data->bw;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = 0;
*val2 = data->scale;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int bma180_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan, int val, int val2, long mask)
{
struct bma180_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
if (val)
return -EINVAL;
mutex_lock(&data->mutex);
ret = bma180_set_scale(data, val2);
mutex_unlock(&data->mutex);
return ret;
case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
mutex_lock(&data->mutex);
ret = bma180_set_bw(data, val);
mutex_unlock(&data->mutex);
return ret;
default:
return -EINVAL;
}
}
static int bma180_update_scan_mode(struct iio_dev *indio_dev,
const unsigned long *scan_mask)
{
struct bma180_data *data = iio_priv(indio_dev);
if (data->buff)
devm_kfree(&indio_dev->dev, data->buff);
data->buff = devm_kzalloc(&indio_dev->dev,
indio_dev->scan_bytes, GFP_KERNEL);
if (!data->buff)
return -ENOMEM;
return 0;
}
static const struct iio_info bma180_info = {
.attrs = &bma180_attrs_group,
.read_raw = bma180_read_raw,
.write_raw = bma180_write_raw,
.update_scan_mode = bma180_update_scan_mode,
.driver_module = THIS_MODULE,
};
static const char * const bma180_power_modes[] = {
BMA180_LOW_NOISE_STR,
BMA180_LOW_POWER_STR,
};
static int bma180_get_power_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan)
{
struct bma180_data *data = iio_priv(indio_dev);
return data->pmode;
}
static int bma180_set_power_mode(struct iio_dev *indio_dev,
const struct iio_chan_spec *chan, unsigned int mode)
{
struct bma180_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
ret = bma180_set_pmode(data, mode);
mutex_unlock(&data->mutex);
return ret;
}
static const struct iio_enum bma180_power_mode_enum = {
.items = bma180_power_modes,
.num_items = ARRAY_SIZE(bma180_power_modes),
.get = bma180_get_power_mode,
.set = bma180_set_power_mode,
};
static const struct iio_chan_spec_ext_info bma180_ext_info[] = {
IIO_ENUM("power_mode", true, &bma180_power_mode_enum),
IIO_ENUM_AVAILABLE("power_mode", &bma180_power_mode_enum),
{ },
};
#define BMA180_CHANNEL(_index) { \
.type = IIO_ACCEL, \
.indexed = 1, \
.channel = (_index), \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
.scan_index = (_index), \
.scan_type = IIO_ST('s', 14, 16, 2), \
.ext_info = bma180_ext_info, \
}
static const struct iio_chan_spec bma180_channels[] = {
BMA180_CHANNEL(AXIS_X),
BMA180_CHANNEL(AXIS_Y),
BMA180_CHANNEL(AXIS_Z),
IIO_CHAN_SOFT_TIMESTAMP(4),
};
static irqreturn_t bma180_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct bma180_data *data = iio_priv(indio_dev);
int bit, ret, i = 0;
mutex_lock(&data->mutex);
if (indio_dev->scan_timestamp) {
ret = indio_dev->scan_bytes / sizeof(s64) - 1;
((s64 *)data->buff)[ret] = iio_get_time_ns();
}
for_each_set_bit(bit, indio_dev->buffer->scan_mask,
indio_dev->masklength) {
ret = bma180_get_acc_reg(data, bit);
if (ret < 0) {
mutex_unlock(&data->mutex);
goto err;
}
((s16 *)data->buff)[i++] = ret;
}
mutex_unlock(&data->mutex);
iio_push_to_buffers(indio_dev, (u8 *)data->buff);
err:
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
static int bma180_data_rdy_trigger_set_state(struct iio_trigger *trig,
bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct bma180_data *data = iio_priv(indio_dev);
return bma180_set_new_data_intr_state(data, state);
}
static int bma180_trig_try_reen(struct iio_trigger *trig)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct bma180_data *data = iio_priv(indio_dev);
return bma180_reset_intr(data);
}
static const struct iio_trigger_ops bma180_trigger_ops = {
.set_trigger_state = bma180_data_rdy_trigger_set_state,
.try_reenable = bma180_trig_try_reen,
.owner = THIS_MODULE,
};
static int bma180_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct bma180_data *data;
struct iio_dev *indio_dev;
struct iio_trigger *trig;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
ret = bma180_chip_init(data);
if (ret < 0)
goto err_chip_disable;
mutex_init(&data->mutex);
indio_dev->dev.parent = &client->dev;
indio_dev->channels = bma180_channels;
indio_dev->num_channels = ARRAY_SIZE(bma180_channels);
indio_dev->name = BMA180_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->info = &bma180_info;
trig = iio_trigger_alloc("%s-dev%d", indio_dev->name, indio_dev->id);
if (!trig) {
ret = -ENOMEM;
goto err_chip_disable;
}
ret = devm_request_irq(&client->dev, client->irq,
iio_trigger_generic_data_rdy_poll,
IRQF_TRIGGER_RISING, BMA180_IRQ_NAME, trig);
if (ret) {
dev_err(&client->dev, "unable to request IRQ\n");
goto err_trigger_free;
}
trig->dev.parent = &client->dev;
trig->ops = &bma180_trigger_ops;
iio_trigger_set_drvdata(trig, indio_dev);
data->trig = trig;
indio_dev->trig = trig;
ret = iio_trigger_register(trig);
if (ret)
goto err_trigger_free;
ret = iio_triggered_buffer_setup(indio_dev, NULL,
bma180_trigger_handler, NULL);
if (ret < 0) {
dev_err(&client->dev, "unable to setup iio triggered buffer\n");
goto err_trigger_unregister;
}
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev, "unable to register iio device\n");
goto err_buffer_cleanup;
}
return 0;
err_buffer_cleanup:
iio_triggered_buffer_cleanup(indio_dev);
err_trigger_unregister:
iio_trigger_unregister(trig);
err_trigger_free:
iio_trigger_free(trig);
err_chip_disable:
bma180_chip_disable(data);
return ret;
}
static int bma180_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
struct bma180_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
iio_trigger_unregister(data->trig);
iio_trigger_free(data->trig);
mutex_lock(&data->mutex);
bma180_chip_disable(data);
mutex_unlock(&data->mutex);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int bma180_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct bma180_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
ret = bma180_set_sleep_state(data, 1);
mutex_unlock(&data->mutex);
return ret;
}
static int bma180_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_to_iio_dev(dev);
struct bma180_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->mutex);
ret = bma180_set_sleep_state(data, 0);
mutex_unlock(&data->mutex);
return ret;
}
static SIMPLE_DEV_PM_OPS(bma180_pm_ops, bma180_suspend, bma180_resume);
#define BMA180_PM_OPS (&bma180_pm_ops)
#else
#define BMA180_PM_OPS NULL
#endif
static struct i2c_device_id bma180_id[] = {
{ BMA180_DRV_NAME, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, bma180_id);
static struct i2c_driver bma180_driver = {
.driver = {
.name = BMA180_DRV_NAME,
.owner = THIS_MODULE,
.pm = BMA180_PM_OPS,
},
.probe = bma180_probe,
.remove = bma180_remove,
.id_table = bma180_id,
};
module_i2c_driver(bma180_driver);
MODULE_AUTHOR("Kravchenko Oleksandr <x0199363@ti.com>");
MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_DESCRIPTION("Bosch BMA180 triaxial acceleration sensor");
MODULE_LICENSE("GPL");