drivers/iio/common/hid-sensors/hid-sensor-attributes.c - kernel/bruno - Git at Google

 /*
  * 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_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},
 };

 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)
 		ret = -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)/value;
 		else
 			value = 0;
 	}
 	ret = sensor_hub_set_feature(st->hsdev, st->poll.report_id,
 				     st->poll.index, sizeof(value), &value);
 	if (ret < 0 || value < 0)
 		ret = -EINVAL;

 	return ret;
 }
 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);

 int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
 				int *val1, int *val2)
 {
 	s32 value;
 	int ret;

 	ret = sensor_hub_get_feature(st->hsdev,
 				     st->sensitivity.report_id,
 				     st->sensitivity.index, sizeof(value),
 				     &value);
 	if (ret < 0 || value < 0) {
 		*val1 = *val2 = 0;
 		return -EINVAL;
 	} else {
 		convert_from_vtf_format(value, st->sensitivity.size,
 					st->sensitivity.unit_expo,
 					val1, val2);
 	}

 	return IIO_VAL_INT_PLUS_MICRO;
 }
 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);

 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
 					int val1, int val2)
 {
 	s32 value;
 	int ret;

 	value = convert_to_vtf_format(st->sensitivity.size,
 				st->sensitivity.unit_expo,
 				val1, val2);
 	ret = sensor_hub_set_feature(st->hsdev, st->sensitivity.report_id,
 				     st->sensitivity.index, sizeof(value),
 				     &value);
 	if (ret < 0 || value < 0)
 		ret = -EINVAL;

 	return ret;
 }
 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);

 /*
  * This fuction applies the unit exponent to the scale.
  * For example:
  * 9.806650000 ->exp:2-> val0[980]val1[665000000]
  * 9.000806000 ->exp:2-> val0[900]val1[80600000]
  * 0.174535293 ->exp:2-> val0[17]val1[453529300]
  * 1.001745329 ->exp:0-> val0[1]val1[1745329]
  * 1.001745329 ->exp:2-> val0[100]val1[174532900]
  * 1.001745329 ->exp:4-> val0[10017]val1[453290000]
  * 9.806650000 ->exp:-2-> val0[0]val1[98066500]
  */
 static void adjust_exponent_nano(int *val0, int *val1, int scale0,
 				  int scale1, int exp)
 {
 	int i;
 	int x;
 	int res;
 	int rem;

 	if (exp > 0) {
 		*val0 = scale0 * pow_10(exp);
 		res = 0;
 		if (exp > 9) {
 			*val1 = 0;
 			return;
 		}
 		for (i = 0; i < exp; ++i) {
 			x = scale1 / pow_10(8 - i);
 			res += (pow_10(exp - 1 - i) * x);
 			scale1 = scale1 % pow_10(8 - i);
 		}
 		*val0 += res;
 			*val1 = scale1 * pow_10(exp);
 	} else if (exp < 0) {
 		exp = abs(exp);
 		if (exp > 9) {
 			*val0 = *val1 = 0;
 			return;
 		}
 		*val0 = scale0 / pow_10(exp);
 		rem = scale0 % pow_10(exp);
 		res = 0;
 		for (i = 0; i < (9 - exp); ++i) {
 			x = scale1 / pow_10(8 - i);
 			res += (pow_10(8 - exp - i) * x);
 			scale1 = scale1 % pow_10(8 - i);
 		}
 		*val1 = rem * pow_10(9 - exp) + res;
 	} else {
 		*val0 = scale0;
 		*val1 = scale1;
 	}
 }

 int hid_sensor_format_scale(u32 usage_id,
 			struct hid_sensor_hub_attribute_info *attr_info,
 			int *val0, int *val1)
 {
 	int i;
 	int exp;

 	*val0 = 1;
 	*val1 = 0;

 	for (i = 0; i < ARRAY_SIZE(unit_conversion); ++i) {
 		if (unit_conversion[i].usage_id == usage_id &&
 			unit_conversion[i].unit == attr_info->units) {
 			exp  = hid_sensor_convert_exponent(
 						attr_info->unit_expo);
 			adjust_exponent_nano(val0, val1,
 					unit_conversion[i].scale_val0,
 					unit_conversion[i].scale_val1, exp);
 			break;
 		}
 	}

 	return IIO_VAL_INT_PLUS_NANO;
 }
 EXPORT_SYMBOL(hid_sensor_format_scale);

 static
 int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
 					u32 usage_id,
 					struct hid_sensor_common *st)
 {
 	sensor_hub_input_get_attribute_info(hsdev,
 					HID_FEATURE_REPORT, usage_id,
 					HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
 					&st->poll);
 	/* Default unit of measure is milliseconds */
 	if (st->poll.units == 0)
 		st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
 	return 0;

 }

 int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 					u32 usage_id,
 					struct hid_sensor_common *st)
 {


 	hid_sensor_get_reporting_interval(hsdev, usage_id, st);

 	sensor_hub_input_get_attribute_info(hsdev,
 					HID_FEATURE_REPORT, usage_id,
 					HID_USAGE_SENSOR_PROP_REPORT_STATE,
 					&st->report_state);

 	sensor_hub_input_get_attribute_info(hsdev,
 					HID_FEATURE_REPORT, usage_id,
 					HID_USAGE_SENSOR_PROY_POWER_STATE,
 					&st->power_state);

 	sensor_hub_input_get_attribute_info(hsdev,
 			HID_FEATURE_REPORT, usage_id,
 			HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
 			 &st->sensitivity);

 	hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x\n",
 			st->poll.index, st->poll.report_id,
 			st->report_state.index, st->report_state.report_id,
 			st->power_state.index, st->power_state.report_id,
 			st->sensitivity.index, st->sensitivity.report_id);

 	return 0;
 }
 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);

 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 MODULE_DESCRIPTION("HID Sensor common attribute processing");
 MODULE_LICENSE("GPL");
	/*
	* 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_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},
	};

	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)
	ret = -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)/value;
	else
	value = 0;
	}
	ret = sensor_hub_set_feature(st->hsdev, st->poll.report_id,
	st->poll.index, sizeof(value), &value);
	if (ret < 0 \|\| value < 0)
	ret = -EINVAL;

	return ret;
	}
	EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);

	int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
	int val1, int val2)
	{
	s32 value;
	int ret;

	ret = sensor_hub_get_feature(st->hsdev,
	st->sensitivity.report_id,
	st->sensitivity.index, sizeof(value),
	&value);
	if (ret < 0 \|\| value < 0) {
	val1 = val2 = 0;
	return -EINVAL;
	} else {
	convert_from_vtf_format(value, st->sensitivity.size,
	st->sensitivity.unit_expo,
	val1, val2);
	}

	return IIO_VAL_INT_PLUS_MICRO;
	}
	EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);

	int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
	int val1, int val2)
	{
	s32 value;
	int ret;

	value = convert_to_vtf_format(st->sensitivity.size,
	st->sensitivity.unit_expo,
	val1, val2);
	ret = sensor_hub_set_feature(st->hsdev, st->sensitivity.report_id,
	st->sensitivity.index, sizeof(value),
	&value);
	if (ret < 0 \|\| value < 0)
	ret = -EINVAL;

	return ret;
	}
	EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);

	/*
	* This fuction applies the unit exponent to the scale.
	* For example:
	* 9.806650000 ->exp:2-> val0[980]val1[665000000]
	* 9.000806000 ->exp:2-> val0[900]val1[80600000]
	* 0.174535293 ->exp:2-> val0[17]val1[453529300]
	* 1.001745329 ->exp:0-> val0[1]val1[1745329]
	* 1.001745329 ->exp:2-> val0[100]val1[174532900]
	* 1.001745329 ->exp:4-> val0[10017]val1[453290000]
	* 9.806650000 ->exp:-2-> val0[0]val1[98066500]
	*/
	static void adjust_exponent_nano(int val0, int val1, int scale0,
	int scale1, int exp)
	{
	int i;
	int x;
	int res;
	int rem;

	if (exp > 0) {
	val0 = scale0 pow_10(exp);
	res = 0;
	if (exp > 9) {
	*val1 = 0;
	return;
	}
	for (i = 0; i < exp; ++i) {
	x = scale1 / pow_10(8 - i);
	res += (pow_10(exp - 1 - i) * x);
	scale1 = scale1 % pow_10(8 - i);
	}
	*val0 += res;
	val1 = scale1 pow_10(exp);
	} else if (exp < 0) {
	exp = abs(exp);
	if (exp > 9) {
	val0 = val1 = 0;
	return;
	}
	*val0 = scale0 / pow_10(exp);
	rem = scale0 % pow_10(exp);
	res = 0;
	for (i = 0; i < (9 - exp); ++i) {
	x = scale1 / pow_10(8 - i);
	res += (pow_10(8 - exp - i) * x);
	scale1 = scale1 % pow_10(8 - i);
	}
	val1 = rem pow_10(9 - exp) + res;
	} else {
	*val0 = scale0;
	*val1 = scale1;
	}
	}

	int hid_sensor_format_scale(u32 usage_id,
	struct hid_sensor_hub_attribute_info *attr_info,
	int val0, int val1)
	{
	int i;
	int exp;

	*val0 = 1;
	*val1 = 0;

	for (i = 0; i < ARRAY_SIZE(unit_conversion); ++i) {
	if (unit_conversion[i].usage_id == usage_id &&
	unit_conversion[i].unit == attr_info->units) {
	exp = hid_sensor_convert_exponent(
	attr_info->unit_expo);
	adjust_exponent_nano(val0, val1,
	unit_conversion[i].scale_val0,
	unit_conversion[i].scale_val1, exp);
	break;
	}
	}

	return IIO_VAL_INT_PLUS_NANO;
	}
	EXPORT_SYMBOL(hid_sensor_format_scale);

	static
	int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
	u32 usage_id,
	struct hid_sensor_common *st)
	{
	sensor_hub_input_get_attribute_info(hsdev,
	HID_FEATURE_REPORT, usage_id,
	HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
	&st->poll);
	/* Default unit of measure is milliseconds */
	if (st->poll.units == 0)
	st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
	return 0;

	}

	int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
	u32 usage_id,
	struct hid_sensor_common *st)
	{


	hid_sensor_get_reporting_interval(hsdev, usage_id, st);

	sensor_hub_input_get_attribute_info(hsdev,
	HID_FEATURE_REPORT, usage_id,
	HID_USAGE_SENSOR_PROP_REPORT_STATE,
	&st->report_state);

	sensor_hub_input_get_attribute_info(hsdev,
	HID_FEATURE_REPORT, usage_id,
	HID_USAGE_SENSOR_PROY_POWER_STATE,
	&st->power_state);

	sensor_hub_input_get_attribute_info(hsdev,
	HID_FEATURE_REPORT, usage_id,
	HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
	&st->sensitivity);

	hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x\n",
	st->poll.index, st->poll.report_id,
	st->report_state.index, st->report_state.report_id,
	st->power_state.index, st->power_state.report_id,
	st->sensitivity.index, st->sensitivity.report_id);

	return 0;
	}
	EXPORT_SYMBOL(hid_sensor_parse_common_attributes);

	MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
	MODULE_DESCRIPTION("HID Sensor common attribute processing");
	MODULE_LICENSE("GPL");