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/*
* HID Sensors Driver
* Copyright (c) 2012, 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.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/hid-sensor-hub.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
static struct {
u32 usage_id;
int unit; /* 0 for default others from HID sensor spec */
int scale_val0; /* scale, whole number */
int scale_val1; /* scale, fraction in nanos */
} unit_conversion[] = {
{HID_USAGE_SENSOR_ACCEL_3D, 0, 9, 806650000},
{HID_USAGE_SENSOR_ACCEL_3D,
HID_USAGE_SENSOR_UNITS_METERS_PER_SEC_SQRD, 1, 0},
{HID_USAGE_SENSOR_ACCEL_3D,
HID_USAGE_SENSOR_UNITS_G, 9, 806650000},
{HID_USAGE_SENSOR_GRAVITY_VECTOR, 0, 9, 806650000},
{HID_USAGE_SENSOR_GRAVITY_VECTOR,
HID_USAGE_SENSOR_UNITS_METERS_PER_SEC_SQRD, 1, 0},
{HID_USAGE_SENSOR_GRAVITY_VECTOR,
HID_USAGE_SENSOR_UNITS_G, 9, 806650000},
{HID_USAGE_SENSOR_GYRO_3D, 0, 0, 17453293},
{HID_USAGE_SENSOR_GYRO_3D,
HID_USAGE_SENSOR_UNITS_RADIANS_PER_SECOND, 1, 0},
{HID_USAGE_SENSOR_GYRO_3D,
HID_USAGE_SENSOR_UNITS_DEGREES_PER_SECOND, 0, 17453293},
{HID_USAGE_SENSOR_COMPASS_3D, 0, 0, 1000000},
{HID_USAGE_SENSOR_COMPASS_3D, HID_USAGE_SENSOR_UNITS_GAUSS, 1, 0},
{HID_USAGE_SENSOR_INCLINOMETER_3D, 0, 0, 17453293},
{HID_USAGE_SENSOR_INCLINOMETER_3D,
HID_USAGE_SENSOR_UNITS_DEGREES, 0, 17453293},
{HID_USAGE_SENSOR_INCLINOMETER_3D,
HID_USAGE_SENSOR_UNITS_RADIANS, 1, 0},
{HID_USAGE_SENSOR_ALS, 0, 1, 0},
{HID_USAGE_SENSOR_ALS, HID_USAGE_SENSOR_UNITS_LUX, 1, 0},
{HID_USAGE_SENSOR_PRESSURE, 0, 100, 0},
{HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 0, 1000000},
{HID_USAGE_SENSOR_TIME_TIMESTAMP, 0, 1000000000, 0},
{HID_USAGE_SENSOR_TIME_TIMESTAMP, HID_USAGE_SENSOR_UNITS_MILLISECOND,
1000000, 0},
{HID_USAGE_SENSOR_TEMPERATURE, 0, 1000, 0},
{HID_USAGE_SENSOR_TEMPERATURE, HID_USAGE_SENSOR_UNITS_DEGREES, 1000, 0},
{HID_USAGE_SENSOR_HUMIDITY, 0, 1000, 0},
};
static int pow_10(unsigned power)
{
int i;
int ret = 1;
for (i = 0; i < power; ++i)
ret = ret * 10;
return ret;
}
static void simple_div(int dividend, int divisor, int *whole,
int *micro_frac)
{
int rem;
int exp = 0;
*micro_frac = 0;
if (divisor == 0) {
*whole = 0;
return;
}
*whole = dividend/divisor;
rem = dividend % divisor;
if (rem) {
while (rem <= divisor) {
rem *= 10;
exp++;
}
*micro_frac = (rem / divisor) * pow_10(6-exp);
}
}
static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
{
*val1 = no/pow_10(exp);
*val2 = no%pow_10(exp) * pow_10(6-exp);
}
/*
VTF format uses exponent and variable size format.
For example if the size is 2 bytes
0x0067 with VTF16E14 format -> +1.03
To convert just change to 0x67 to decimal and use two decimal as E14 stands
for 10^-2.
Negative numbers are 2's complement
*/
static void convert_from_vtf_format(u32 value, int size, int exp,
int *val1, int *val2)
{
int sign = 1;
if (value & BIT(size*8 - 1)) {
value = ((1LL << (size * 8)) - value);
sign = -1;
}
exp = hid_sensor_convert_exponent(exp);
if (exp >= 0) {
*val1 = sign * value * pow_10(exp);
*val2 = 0;
} else {
split_micro_fraction(value, -exp, val1, val2);
if (*val1)
*val1 = sign * (*val1);
else
*val2 = sign * (*val2);
}
}
static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
{
u32 value;
int sign = 1;
if (val1 < 0 || val2 < 0)
sign = -1;
exp = hid_sensor_convert_exponent(exp);
if (exp < 0) {
value = abs(val1) * pow_10(-exp);
value += abs(val2) / pow_10(6+exp);
} else
value = abs(val1) / pow_10(exp);
if (sign < 0)
value = ((1LL << (size * 8)) - value);
return value;
}
s32 hid_sensor_read_poll_value(struct hid_sensor_common *st)
{
s32 value = 0;
int ret;
ret = sensor_hub_get_feature(st->hsdev,
st->poll.report_id,
st->poll.index, sizeof(value), &value);
if (ret < 0 || value < 0) {
return -EINVAL;
} else {
if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
value = value * 1000;
}
return value;
}
EXPORT_SYMBOL(hid_sensor_read_poll_value);
int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,
int *val1, int *val2)
{
s32 value;
int ret;
ret = sensor_hub_get_feature(st->hsdev,
st->poll.report_id,
st->poll.index, sizeof(value), &value);
if (ret < 0 || value < 0) {
*val1 = *val2 = 0;
return -EINVAL;
} else {
if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
simple_div(1000, value, val1, val2);
else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
simple_div(1, value, val1, val2);
else {
*val1 = *val2 = 0;
return -EINVAL;
}
}
return IIO_VAL_INT_PLUS_MICRO;
}
EXPORT_SYMBOL(hid_sensor_read_samp_freq_value);
int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
int val1, int val2)
{
s32 value;
int ret;
if (val1 < 0 || val2 < 0)
return -EINVAL;
value = val1 * pow_10(6) + val2;
if (value) {
if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
value = pow_10(9)/value;
else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
value = pow_10(6)/
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