// SPDX-License-Identifier: GPL-2.0-only
/*
* ADXL355 3-Axis Digital Accelerometer IIO core driver
*
* Copyright (c) 2021 Puranjay Mohan <puranjay12@gmail.com>
*
* Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adxl354_adxl355.pdf
*/
#include <linux/bits.h>
#include <linux/bitfield.h>
#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/limits.h>
#include <linux/math64.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/property.h>
#include <linux/regmap.h>
#include <linux/units.h>
#include <asm/unaligned.h>
#include "adxl355.h"
/* ADXL355 Register Definitions */
#define ADXL355_DEVID_AD_REG 0x00
#define ADXL355_DEVID_MST_REG 0x01
#define ADXL355_PARTID_REG 0x02
#define ADXL355_STATUS_REG 0x04
#define ADXL355_FIFO_ENTRIES_REG 0x05
#define ADXL355_TEMP2_REG 0x06
#define ADXL355_XDATA3_REG 0x08
#define ADXL355_YDATA3_REG 0x0B
#define ADXL355_ZDATA3_REG 0x0E
#define ADXL355_FIFO_DATA_REG 0x11
#define ADXL355_OFFSET_X_H_REG 0x1E
#define ADXL355_OFFSET_Y_H_REG 0x20
#define ADXL355_OFFSET_Z_H_REG 0x22
#define ADXL355_ACT_EN_REG 0x24
#define ADXL355_ACT_THRESH_H_REG 0x25
#define ADXL355_ACT_THRESH_L_REG 0x26
#define ADXL355_ACT_COUNT_REG 0x27
#define ADXL355_FILTER_REG 0x28
#define ADXL355_FILTER_ODR_MSK GENMASK(3, 0)
#define ADXL355_FILTER_HPF_MSK GENMASK(6, 4)
#define ADXL355_FIFO_SAMPLES_REG 0x29
#define ADXL355_INT_MAP_REG 0x2A
#define ADXL355_SYNC_REG 0x2B
#define ADXL355_RANGE_REG 0x2C
#define ADXL355_POWER_CTL_REG 0x2D
#define ADXL355_POWER_CTL_MODE_MSK GENMASK(1, 0)
#define ADXL355_POWER_CTL_DRDY_MSK BIT(2)
#define ADXL355_SELF_TEST_REG 0x2E
#define ADXL355_RESET_REG 0x2F
#define ADXL355_DEVID_AD_VAL 0xAD
#define ADXL355_DEVID_MST_VAL 0x1D
#define ADXL355_PARTID_VAL 0xED
#define ADXL355_RESET_CODE 0x52
static const struct regmap_range adxl355_read_reg_range[] = {
regmap_reg_range(ADXL355_DEVID_AD_REG, ADXL355_FIFO_DATA_REG),
regmap_reg_range(ADXL355_OFFSET_X_H_REG, ADXL355_SELF_TEST_REG),
};
const struct regmap_access_table adxl355_readable_regs_tbl = {
.yes_ranges = adxl355_read_reg_range,
.n_yes_ranges = ARRAY_SIZE(adxl355_read_reg_range),
};
EXPORT_SYMBOL_NS_GPL(adxl355_readable_regs_tbl, IIO_ADXL355);
static const struct regmap_range adxl355_write_reg_range[] = {
regmap_reg_range(ADXL355_OFFSET_X_H_REG, ADXL355_RESET_REG),
};
const struct regmap_access_table adxl355_writeable_regs_tbl = {
.yes_ranges = adxl355_write_reg_range,
.n_yes_ranges = ARRAY_SIZE(adxl355_write_reg_range),
};
EXPORT_SYMBOL_NS_GPL(adxl355_writeable_regs_tbl, IIO_ADXL355);
enum adxl355_op_mode {
ADXL355_MEASUREMENT,
ADXL355_STANDBY,
ADXL355_TEMP_OFF,
};
enum adxl355_odr {
ADXL355_ODR_4000HZ,
ADXL355_ODR_2000HZ,
ADXL355_ODR_1000HZ,
ADXL355_ODR_500HZ,
ADXL355_ODR_250HZ,
ADXL355_ODR_125HZ,
ADXL355_ODR_62_5HZ,
ADXL355_ODR_31_25HZ,
ADXL355_ODR_15_625HZ,
ADXL355_ODR_7_813HZ,
ADXL355_ODR_3_906HZ,
};
enum adxl355_hpf_3db {
ADXL355_HPF_OFF,
ADXL355_HPF_24_7,
ADXL355_HPF_6_2084,
ADXL355_HPF_1_5545,
ADXL355_HPF_0_3862,
ADXL355_HPF_0_0954,
ADXL355_HPF_0_0238,
};
static const int adxl355_odr_table[][2] = {
[0] = {4000, 0},
[1] = {2000, 0},
[2] = {1000, 0},
[3] = {500, 0},
[4] = {250, 0},
[5] = {125, 0},
[6] = {62, 500000},
[7] = {31, 250000},
[8] = {15, 625000},
[9] = {7, 813000},
[10] = {3, 906000},
};
static const int adxl355_hpf_3db_multipliers[] = {
0,
247000,
62084,
15545,
3862,
954,
238,
};
enum adxl355_chans {
chan_x, chan_y, chan_z,
};
struct adxl355_chan_info {
u8 data_reg;
u8 offset_reg;
};
static const struct adxl355_chan_info adxl355_chans[] = {
[chan_x] = {
.data_reg = ADXL355_XDATA3_REG,
.offset_reg = ADXL355_OFFSET_X_H_REG
},
[chan_y] = {
.data_reg = ADXL355_YDATA3_REG,
.offset_reg = ADXL355_OFFSET_Y_H_REG
},
[chan_z] = {
.data_reg = ADXL355_ZDATA3_REG,
.offset_reg = ADXL355_OFFSET_Z_H_REG
},
};
struct adxl355_data {
struct regmap *regmap;
struct device *dev;
struct mutex lock; /* lock to protect op_mode */
enum adxl355_op_mode op_mode;
enum adxl355_odr odr;
enum adxl355_hpf_3db hpf_3db;
int calibbias[3];
int adxl355_hpf_3db_table[7][2];
struct iio_trigger *dready_trig;
union {
u8 transf_buf[3];
struct {
u8 buf[14];
s64 ts;
} buffer;
} __aligned(IIO_DMA_MINALIGN);
};
static int adxl355_set_op_mode(struct adxl355_data *data,
enum adxl355_op_mode op_mode)
{
int ret;
if (data->op_mode == op_mode)
return 0;
ret = regmap_update_bits(data->regmap, ADXL355_POWER_CTL_REG,
ADXL355_POWER_CTL_MODE_MSK, op_mode);
if (ret)
return ret;
data->op_mode = op_mode;
return ret;
}
static int adxl355_data_rdy_trigger_set_state(struct iio_trigger *trig,
bool state)
{
struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
struct adxl355_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->lock);
ret = regmap_update_bits(data->regmap, ADXL355_POWER_CTL_REG,
ADXL355_POWER_CTL_DRDY_MSK,
FIELD_PREP(ADXL355_POWER_CTL_DRDY_MSK,
state ? 0 : 1));
mutex_unlock(&data->lock);
return ret;
}
static void adxl355_fill_3db_frequency_table(struct adxl355_data *data)
{
u32 multiplier;
u64 div, rem;
u64 odr;
int i;
odr = mul_u64_u32_shr(adxl355_odr_table[data->odr][0], MEGA, 0) +
adxl355_odr_table[data->odr][1];
for (i = 0; i < ARRAY_SIZE(adxl355_hpf_3db_multipliers); i++) {
multiplier = adxl355_hpf_3db_multipliers[i];
div = div64_u64_rem(mul_u64_u32_shr(odr, multiplier, 0),
TERA * 100, &rem);
data->adxl355_hpf_3db_table[i][0] = div;
data->adxl355_hpf_3db_table[i][1] = div_u64(rem, MEGA * 100);
}
}
static int adxl355_setup(struct adxl355_data *data)
{
unsigned int regval;
int ret;
ret = regmap_read(data->regmap, ADXL355_DEVID_AD_REG, ®val);
if (ret)
return ret;
if (regval != ADXL355_DEVID_AD_VAL) {
dev_err(data->dev, "Invalid ADI ID 0x%02x\n", regval);
return -ENODEV;
}
ret = regmap_read(data->regmap, ADXL355_DEVID_MST_REG, ®val);
if (ret)
return ret;
if (regval != ADXL355_DEVID_MST_VAL) {
dev_err(data->dev, "Invalid MEMS ID 0x%02x\n", regval);
return -ENODEV;
}
ret = regmap_read(data->regmap, ADXL355_PARTID_REG, ®val);
if (ret)
return ret;
if (regval != ADXL355_PARTID_VAL) {
dev_err(data->dev, "Invalid DEV ID 0x%02x\n", regval);
return -ENODEV;
}
/*
* Perform a software reset to make sure the device is in a consistent
* state after start-up.
*/
ret = regmap_write(data->regmap, ADXL355_RESET_REG, ADXL355_RESET_CODE);
if (ret)
return ret;
ret = regmap_update_bits(data->regmap, ADXL355_POWER_CTL_REG,
ADXL355_POWER_CTL_DRDY_MSK,
FIELD_PREP(ADXL355_POWER_CTL_DRDY_MSK, 1));
if (ret)
return ret;
adxl355_fill_3db_frequency_table(data);
return adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
}
static int adxl355_get_temp_data(struct adxl355_data *data, u8 addr)
{
return regmap_bulk_read(data->regmap, addr, data->transf_buf, 2);
}
static int adxl355_read_axis(struct adxl355_data *data, u8 addr)
{
int ret;
ret = regmap_bulk_read(data->regmap, addr, data->transf_buf,
ARRAY_SIZE(data->transf_buf));
if (ret)
return ret;
return get_unaligned_be24(data->transf_buf);
}
static int adxl355_find_match(const int (*freq_tbl)[2], const int n,
const int val, const int val2)
{
int i;
for (i = 0; i < n; i++) {
if (freq_tbl[i][0] == val && freq_tbl[i][1] == val2)
return i;
}
return -EINVAL;
}
static int adxl355_set_odr(struct adxl355_data *data,
enum adxl355_odr odr)
{
int ret;
mutex_lock(&data->lock);
if (data->odr == odr) {
mutex_unlock(&data->lock);
return 0;
}
ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
if (ret)
goto err_unlock;
ret = regmap_update_bits(data->regmap, ADXL355_FILTER_REG,
ADXL355_FILTER_ODR_MSK,
FIELD_PREP(ADXL355_FILTER_ODR_MSK, odr));
if (ret)
goto err_set_opmode;
data->odr = odr;
adxl355_fill_3db_frequency_table(data);
ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
if (ret)
goto err_set_opmode;
mutex_unlock(&data->lock);
return 0;
err_set_opmode:
adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
err_unlock:
mutex_unlock(&data->lock);
return ret;
}
static int adxl355_set_hpf_3db(struct adxl355_data *data,
enum adxl355_hpf_3db hpf)
{
int ret;
mutex_lock(&data->lock);
if (data->hpf_3db == hpf) {
mutex_unlock(&data->lock);
return 0;
}
ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
if (ret)
goto err_unlock;
ret = regmap_update_bits(data->regmap, ADXL355_FILTER_REG,
ADXL355_FILTER_HPF_MSK,
FIELD_PREP(ADXL355_FILTER_HPF_MSK, hpf));
if (ret)
goto err_set_opmode;
data->hpf_3db = hpf;
ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
if (ret)
goto err_set_opmode;
mutex_unlock(&data->lock);
return 0;
err_set_opmode:
adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
err_unlock:
mutex_unlock(&data->lock);
return ret;
}
static int adxl355_set_calibbias(struct adxl355_data *data,
enum adxl355_chans chan, int calibbias)
{
int ret;
mutex_lock(&data->lock);
ret = adxl355_set_op_mode(data, ADXL355_STANDBY);
if (ret)
goto err_unlock;
put_unaligned_be16(calibbias, data->transf_buf);
ret = regmap_bulk_write(data->regmap,
adxl355_chans[chan].offset_reg,
data->transf_buf, 2);
if (ret)
goto err_set_opmode;
data->calibbias[chan] = calibbias;
ret = adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
if (ret)
goto err_set_opmode;
mutex_unlock(&data->lock);
return 0;
err_set_opmode:
adxl355_set_op_mode(data, ADXL355_MEASUREMENT);
err_unlock:
mutex_unlock(&data->lock);
return ret;
}
static int adxl355_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct adxl355_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_TEMP:
ret = adxl355_get_temp_data(data, chan->address);
if (ret < 0)
return ret;
*val = get_unaligned_be16(data->transf_buf);
return IIO_VAL_INT;
case IIO_ACCEL:
ret = adxl355_read_axis(data, adxl355_chans[
chan->address].data_reg);
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:
switch (chan->type) {
/*
* The datasheet defines an intercept of 1885 LSB at 25 degC
* and a slope of -9.05 LSB/C. The following formula can be used
* to find the temperature:
* Temp = ((RAW - 1885)/(-9.05)) + 25 but this doesn't follow
* the format of the IIO which is Temp = (RAW + OFFSET) * SCALE.
* Hence using some rearranging we get the scale as -110.497238
* and offset as -2111.25.
*/
case IIO_TEMP:
*val = -110;
*val2 = 497238;
return IIO_VAL_INT_PLUS_MICRO;
/*
* At +/- 2g with 20-bit resolution, scale is given in datasheet
* as 3.9ug/LSB = 0.0000039 * 9.80665 = 0.00003824593 m/s^2.
*/
case IIO_ACCEL:
*val = 0;
*val2 = 38245;
return IIO_VAL_INT_PLUS_NANO;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_OFFSET:
*val = -2111;
*val2 = 250000;
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_CALIBBIAS:
*val = sign_extend32(data->calibbias[chan->address], 15);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SAMP_FREQ:
*val = adxl355_odr_table[data->odr][0];
*val2 = adxl355_odr_table[data->odr][1];
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
*val = data->adxl355_hpf_3db_table[data->hpf_3db][0];
*val2 = data->adxl355_hpf_3db_table[data->hpf_3db][1];
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int adxl355_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct adxl355_data *data = iio_priv(indio_dev);
int odr_idx, hpf_idx, calibbias;
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
odr_idx = adxl355_find_match(adxl355_odr_table,
ARRAY_SIZE(adxl355_odr_table),
val, val2);
if (odr_idx < 0)
return odr_idx;
return adxl355_set_odr(data, odr_idx);
case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
hpf_idx = adxl355_find_match(data->adxl355_hpf_3db_table,
ARRAY_SIZE(data->adxl355_hpf_3db_table),
val, val2);
if (hpf_idx < 0)
return hpf_idx;
return adxl355_set_hpf_3db(data, hpf_idx);
case IIO_CHAN_INFO_CALIBBIAS:
calibbias = clamp_t(int, val, S16_MIN, S16_MAX);
return adxl355_set_calibbias(data, chan->address, calibbias);
default:
return -EINVAL;
}
}
static int adxl355_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type, int *length,
long mask)
{
struct adxl355_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_SAMP_FREQ:
*vals = (const int *)adxl355_odr_table;
*type = IIO_VAL_INT_PLUS_MICRO;
/* Values are stored in a 2D matrix */
*length = ARRAY_SIZE(adxl355_odr_table) * 2;
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
*vals = (const int *)data->adxl355_hpf_3db_table;
*type = IIO_VAL_INT_PLUS_MICRO;
/* Values are stored in a 2D matrix */
*length = ARRAY_SIZE(data->adxl355_hpf_3db_table) * 2;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static const unsigned long adxl355_avail_scan_masks[] = {
GENMASK(3, 0),
0
};
static const struct iio_info adxl355_info = {
.read_raw = adxl355_read_raw,
.write_raw = adxl355_write_raw,
.read_avail = &adxl355_read_avail,
};
static const struct iio_trigger_ops adxl355_trigger_ops = {
.set_trigger_state = &adxl355_data_rdy_trigger_set_state,
.validate_device = &iio_trigger_validate_own_device,
};
static irqreturn_t adxl355_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct adxl355_data *data = iio_priv(indio_dev);
int ret;
mutex_lock(&data->lock);
/*
* data->buffer is used both for triggered buffer support
* and read/write_raw(), hence, it has to be zeroed here before usage.
*/
data->buffer.buf[0] = 0;
/*
* The acceleration data is 24 bits and big endian. It has to be saved
* in 32 bits, hence, it is saved in the 2nd byte of the 4 byte buffer.
* The buf array is 14 bytes as it includes 3x4=12 bytes for
* accelaration data of x, y, and z axis. It also includes 2 bytes for
* temperature data.
*/
ret = regmap_bulk_read(data->regmap, ADXL355_XDATA3_REG,
&data->buffer.buf[1], 3);
if (ret)
goto out_unlock_notify;
ret = regmap_bulk_read(data->regmap, ADXL355_YDATA3_REG,
&data->buffer.buf[5], 3);
if (ret)
goto out_unlock_notify;
ret = regmap_bulk_read(data->regmap, ADXL355_ZDATA3_REG,
&data->buffer.buf[9], 3);
if (ret)
goto out_unlock_notify;
ret = regmap_bulk_read(data->regmap, ADXL355_TEMP2_REG,
&data->buffer.buf[12], 2);
if (ret)
goto out_unlock_notify;
iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
pf->timestamp);
out_unlock_notify:
mutex_unlock(&data->lock);
iio_trigger_notify_done(indio_dev->trig);
return IRQ_HANDLED;
}
#define ADXL355_ACCEL_CHANNEL(index, reg, axis) { \
.type = IIO_ACCEL, \
.address = reg, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_CALIBBIAS), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
.info_mask_shared_by_type_available = \
BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY), \
.scan_index = index, \
.scan_type = { \
.sign = 's', \
.realbits = 20, \
.storagebits = 32, \
.shift = 4, \
.endianness = IIO_BE, \
} \
}
static const struct iio_chan_spec adxl355_channels[] = {
ADXL355_ACCEL_CHANNEL(0, chan_x, X),
ADXL355_ACCEL_CHANNEL(1, chan_y, Y),
ADXL355_ACCEL_CHANNEL(2, chan_z, Z),
{
.type = IIO_TEMP,
.address = ADXL355_TEMP2_REG,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE) |
BIT(IIO_CHAN_INFO_OFFSET),
.scan_index = 3,
.scan_type = {
.sign = 's',
.realbits = 12,
.storagebits = 16,
.endianness = IIO_BE,
},
},
IIO_CHAN_SOFT_TIMESTAMP(4),
};
static int adxl355_probe_trigger(struct iio_dev *indio_dev, int irq)
{
struct adxl355_data *data = iio_priv(indio_dev);
int ret;
data->dready_trig = devm_iio_trigger_alloc(data->dev, "%s-dev%d",
indio_dev->name,
iio_device_id(indio_dev));
if (!data->dready_trig)
return -ENOMEM;
data->dready_trig->ops = &adxl355_trigger_ops;
iio_trigger_set_drvdata(data->dready_trig, indio_dev);
ret = devm_request_irq(data->dev, irq,
&iio_trigger_generic_data_rdy_poll,
IRQF_ONESHOT, "adxl355_irq", data->dready_trig);
if (ret)
return dev_err_probe(data->dev, ret, "request irq %d failed\n",
irq);
ret = devm_iio_trigger_register(data->dev, data->dready_trig);
if (ret) {
dev_err(data->dev, "iio trigger register failed\n");
return ret;
}
indio_dev->trig = iio_trigger_get(data->dready_trig);
return 0;
}
int adxl355_core_probe(struct device *dev, struct regmap *regmap,
const char *name)
{
struct adxl355_data *data;
struct iio_dev *indio_dev;
int ret;
int irq;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->regmap = regmap;
data->dev = dev;
data->op_mode = ADXL355_STANDBY;
mutex_init(&data->lock);
indio_dev->name = name;
indio_dev->info = &adxl355_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = adxl355_channels;
indio_dev->num_channels = ARRAY_SIZE(adxl355_channels);
indio_dev->available_scan_masks = adxl355_avail_scan_masks;
ret = adxl355_setup(data);
if (ret) {
dev_err(dev, "ADXL355 setup failed\n");
return ret;
}
ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
&iio_pollfunc_store_time,
&adxl355_trigger_handler, NULL);
if (ret) {
dev_err(dev, "iio triggered buffer setup failed\n");
return ret;
}
irq = fwnode_irq_get_byname(dev_fwnode(dev), "DRDY");
if (irq > 0) {
ret = adxl355_probe_trigger(indio_dev, irq);
if (ret)
return ret;
}
return devm_iio_device_register(dev, indio_dev);
}
EXPORT_SYMBOL_NS_GPL(adxl355_core_probe, IIO_ADXL355);
MODULE_AUTHOR("Puranjay Mohan <puranjay12@gmail.com>");
MODULE_DESCRIPTION("ADXL355 3-Axis Digital Accelerometer core driver");
MODULE_LICENSE("GPL v2");
