diff options
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/common/hid-sensors/hid-sensor-attributes.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c index 75b54730a963..e61b1faa1e06 100644 --- a/drivers/iio/common/hid-sensors/hid-sensor-attributes.c +++ b/drivers/iio/common/hid-sensors/hid-sensor-attributes.c @@ -26,6 +26,40 @@ #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> +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 micros */ +} static unit_conversion[] = { + {HID_USAGE_SENSOR_ACCEL_3D, 0, 9, 806650}, + {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, 806650}, + + {HID_USAGE_SENSOR_GYRO_3D, 0, 0, 17453}, + {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, 17453}, + + {HID_USAGE_SENSOR_COMPASS_3D, 0, 0, 1000}, + {HID_USAGE_SENSOR_COMPASS_3D, HID_USAGE_SENSOR_UNITS_GAUSS, 1, 0}, + + {HID_USAGE_SENSOR_INCLINOMETER_3D, 0, 0, 17453}, + {HID_USAGE_SENSOR_INCLINOMETER_3D, + HID_USAGE_SENSOR_UNITS_DEGREES, 0, 17453}, + {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, 100000, 0}, + {HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 1, 0}, +}; + static int pow_10(unsigned power) { int i; @@ -209,6 +243,86 @@ int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st, } EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value); +/* + * This fuction applies the unit exponent to the scale. + * For example: + * 9.806650 ->exp:2-> val0[980]val1[665000] + * 9.000806 ->exp:2-> val0[900]val1[80600] + * 0.174535 ->exp:2-> val0[17]val1[453500] + * 1.001745 ->exp:0-> val0[1]val1[1745] + * 1.001745 ->exp:2-> val0[100]val1[174500] + * 1.001745 ->exp:4-> val0[10017]val1[450000] + * 9.806650 ->exp:-2-> val0[0]val1[98066] + */ +static void adjust_exponent_micro(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 > 6) { + *val1 = 0; + return; + } + for (i = 0; i < exp; ++i) { + x = scale1 / pow_10(5 - i); + res += (pow_10(exp - 1 - i) * x); + scale1 = scale1 % pow_10(5 - i); + } + *val0 += res; + *val1 = scale1 * pow_10(exp); + } else if (exp < 0) { + exp = abs(exp); + if (exp > 6) { + *val0 = *val1 = 0; + return; + } + *val0 = scale0 / pow_10(exp); + rem = scale0 % pow_10(exp); + res = 0; + for (i = 0; i < (6 - exp); ++i) { + x = scale1 / pow_10(5 - i); + res += (pow_10(5 - exp - i) * x); + scale1 = scale1 % pow_10(5 - i); + } + *val1 = rem * pow_10(6 - 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; 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_micro(val0, val1, + unit_conversion[i].scale_val0, + unit_conversion[i].scale_val1, exp); + break; + } + } + + return IIO_VAL_INT_PLUS_MICRO; +} +EXPORT_SYMBOL(hid_sensor_format_scale); + int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev, u32 usage_id, struct hid_sensor_common *st) |