Add relative hysteresis support for hid sensors

@@ -263,6 +263,30 @@ int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
 }
 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);
 
+int hid_sensor_read_raw_hyst_rel_value(struct hid_sensor_common *st, int *val1,
+				       int *val2)
+{
+	s32 value;
+	int ret;
+
+	ret = sensor_hub_get_feature(st->hsdev,
+				     st->sensitivity_rel.report_id,
+				     st->sensitivity_rel.index, sizeof(value),
+				     &value);
+	if (ret < 0 || value < 0) {
+		*val1 = *val2 = 0;
+		return -EINVAL;
+	} else {
+		convert_from_vtf_format(value, st->sensitivity_rel.size,
+					st->sensitivity_rel.unit_expo,
+					val1, val2);
+	}
+
+	return IIO_VAL_INT_PLUS_MICRO;
+}
+EXPORT_SYMBOL(hid_sensor_read_raw_hyst_rel_value);
+
+
 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
 					int val1, int val2)
 {

@@ -294,6 +318,37 @@ int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
 }
 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
 
+int hid_sensor_write_raw_hyst_rel_value(struct hid_sensor_common *st,
+					int val1, int val2)
+{
+	s32 value;
+	int ret;
+
+	if (val1 < 0 || val2 < 0)
+		return -EINVAL;
+
+	value = convert_to_vtf_format(st->sensitivity_rel.size,
+				st->sensitivity_rel.unit_expo,
+				val1, val2);
+	ret = sensor_hub_set_feature(st->hsdev, st->sensitivity_rel.report_id,
+				     st->sensitivity_rel.index, sizeof(value),
+				     &value);
+	if (ret < 0 || value < 0)
+		return -EINVAL;
+
+	ret = sensor_hub_get_feature(st->hsdev,
+				     st->sensitivity_rel.report_id,
+				     st->sensitivity_rel.index, sizeof(value),
+				     &value);
+	if (ret < 0 || value < 0)
+		return -EINVAL;
+
+	st->raw_hystersis = value;
+
+	return 0;
+}
+EXPORT_SYMBOL(hid_sensor_write_raw_hyst_rel_value);
+
 /*
  * This fuction applies the unit exponent to the scale.
  * For example:

@@ -478,16 +533,28 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 			HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
 			 &st->sensitivity);
 
+	sensor_hub_input_get_attribute_info(hsdev,
+			HID_FEATURE_REPORT, usage_id,
+			HID_USAGE_SENSOR_PROP_SENSITIVITY_REL_PCT,
+			&st->sensitivity_rel);
 	/*
 	 * Set Sensitivity field ids, when there is no individual modifier, will
-	 * check absolute sensitivity of data field
+	 * check absolute sensitivity and relative sensitivity of data field
 	 */
-	for (i = 0; i < sensitivity_addresses_len && st->sensitivity.index < 0; i++) {
-		sensor_hub_input_get_attribute_info(hsdev,
-				HID_FEATURE_REPORT, usage_id,
+	for (i = 0; i < sensitivity_addresses_len; i++) {
+		if (st->sensitivity.index < 0)
+			sensor_hub_input_get_attribute_info(
+				hsdev, HID_FEATURE_REPORT, usage_id,
 				HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS |
 					sensitivity_addresses[i],
 				&st->sensitivity);
+
+		if (st->sensitivity_rel.index < 0)
+			sensor_hub_input_get_attribute_info(
+				hsdev, HID_FEATURE_REPORT, usage_id,
+				HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_REL_PCT |
+					sensitivity_addresses[i],
+				&st->sensitivity_rel);
 	}
 
 	st->raw_hystersis = -1;

@@ -157,6 +157,7 @@ static const char * const iio_chan_info_postfix[] = {
 	[IIO_CHAN_INFO_PHASE] = "phase",
 	[IIO_CHAN_INFO_HARDWAREGAIN] = "hardwaregain",
 	[IIO_CHAN_INFO_HYSTERESIS] = "hysteresis",
+	[IIO_CHAN_INFO_HYSTERESIS_RELATIVE] = "hysteresis_relative",
 	[IIO_CHAN_INFO_INT_TIME] = "integration_time",
 	[IIO_CHAN_INFO_ENABLE] = "en",
 	[IIO_CHAN_INFO_CALIBHEIGHT] = "calibheight",

@@ -230,6 +230,7 @@ struct hid_sensor_common {
 	struct hid_sensor_hub_attribute_info report_state;
 	struct hid_sensor_hub_attribute_info power_state;
 	struct hid_sensor_hub_attribute_info sensitivity;
+	struct hid_sensor_hub_attribute_info sensitivity_rel;
 	struct hid_sensor_hub_attribute_info report_latency;
 	struct work_struct work;
 };

@@ -252,8 +253,12 @@ int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 					u32 sensitivity_addresses_len);
 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
 					int val1, int val2);
+int hid_sensor_write_raw_hyst_rel_value(struct hid_sensor_common *st, int val1,
+					int val2);
 int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
 					int *val1, int *val2);
+int hid_sensor_read_raw_hyst_rel_value(struct hid_sensor_common *st,
+				       int *val1, int *val2);
 int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
 					int val1, int val2);
 int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,

@@ -149,6 +149,7 @@
 /* Per data field properties */
 #define HID_USAGE_SENSOR_DATA_MOD_NONE					0x00
 #define HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_ABS		0x1000
+#define HID_USAGE_SENSOR_DATA_MOD_CHANGE_SENSITIVITY_REL_PCT            0xE000
 
 /* Power state enumerations */
 #define HID_USAGE_SENSOR_PROP_POWER_STATE_UNDEFINED_ENUM	0x200850

@@ -50,6 +50,7 @@ enum iio_chan_info_enum {
 	IIO_CHAN_INFO_PHASE,
 	IIO_CHAN_INFO_HARDWAREGAIN,
 	IIO_CHAN_INFO_HYSTERESIS,
+	IIO_CHAN_INFO_HYSTERESIS_RELATIVE,
 	IIO_CHAN_INFO_INT_TIME,
 	IIO_CHAN_INFO_ENABLE,
 	IIO_CHAN_INFO_CALIBHEIGHT,

@@ -54,7 +54,8 @@ static const struct iio_chan_spec als_channels[] = {
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
-		BIT(IIO_CHAN_INFO_HYSTERESIS),
+		BIT(IIO_CHAN_INFO_HYSTERESIS) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
 		.scan_index = CHANNEL_SCAN_INDEX_INTENSITY,
 	},
 	{

@@ -63,7 +64,8 @@ static const struct iio_chan_spec als_channels[] = {
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 		BIT(IIO_CHAN_INFO_SCALE) |
 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |
-		BIT(IIO_CHAN_INFO_HYSTERESIS),
+		BIT(IIO_CHAN_INFO_HYSTERESIS) |
+		BIT(IIO_CHAN_INFO_HYSTERESIS_RELATIVE),
 		.scan_index = CHANNEL_SCAN_INDEX_ILLUM,
 	},
 	IIO_CHAN_SOFT_TIMESTAMP(CHANNEL_SCAN_INDEX_TIMESTAMP)

@@ -141,6 +143,10 @@ static int als_read_raw(struct iio_dev *indio_dev,
 		ret_type = hid_sensor_read_raw_hyst_value(
 				&als_state->common_attributes, val, val2);
 		break;
+	case IIO_CHAN_INFO_HYSTERESIS_RELATIVE:
+		ret_type = hid_sensor_read_raw_hyst_rel_value(
+				&als_state->common_attributes, val, val2);
+		break;
 	default:
 		ret_type = -EINVAL;
 		break;

@@ -168,6 +174,10 @@ static int als_write_raw(struct iio_dev *indio_dev,
 		ret = hid_sensor_write_raw_hyst_value(
 				&als_state->common_attributes, val, val2);
 		break;
+	case IIO_CHAN_INFO_HYSTERESIS_RELATIVE:
+		ret = hid_sensor_write_raw_hyst_rel_value(
+				&als_state->common_attributes, val, val2);
+		break;
 	default:
 		ret = -EINVAL;
 	}

@@ -1823,3 +1823,11 @@ Description:
 		hinge, keyboard, screen. It means the three channels
 		each correspond respectively to hinge angle, keyboard angle,
 		and screen angle.
+
+What:		/sys/bus/iio/devices/iio:deviceX/in_Y_hysteresis_relative
+KernelVersion:	5.12
+Contact:	linux-iio@vger.kernel.org
+Description:
+		Specify the percent relative to the current sensor channel
+		Y absolute value that a data field should change before an event
+		is generated. Units are a percentage of the prior reading.