[PATCH 1/4] ACPI / LPAT: Common table processing functions

[PATCH 1/4] ACPI / LPAT: Common table processing functions

[Srinivas Pandruvada]

Since LPAT table processing is also required for other thermal drivers,
moved LPAT table related functions from intel PMIC driver (intel_pmic.c)
to a stand alonge module with exported interfaces.
In this way there will be no code duplication.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/acpi/Makefile    |   1 +
 drivers/acpi/acpi_lpat.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++
 include/acpi/acpi_lpat.h |  65 +++++++++++++++++++
 3 files changed, 227 insertions(+)
 create mode 100644 drivers/acpi/acpi_lpat.c
 create mode 100644 include/acpi/acpi_lpat.h

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index f74317c..d22253d 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -55,6 +55,7 @@ acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
 ifdef CONFIG_ACPI_VIDEO
 acpi-y				+= video_detect.o
 endif
+acpi-y				+= acpi_lpat.o
 
 # These are (potentially) separate modules
 
diff --git a/drivers/acpi/acpi_lpat.c b/drivers/acpi/acpi_lpat.c
new file mode 100644
index 0000000..feb61c1
--- /dev/null
+++ b/drivers/acpi/acpi_lpat.c
@@ -0,0 +1,161 @@
+/*
+ * acpi_lpat.c - LPAT table processing functions
+ *
+ * Copyright (C) 2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_lpat.h>
+
+/**
+ * acpi_lpat_raw_to_temp(): Return temperature from raw value through
+ * LPAT conversion table
+ *
+ * @lpat_table: the temperature_raw mapping table structure
+ * @raw: the raw value, used as a key to get the temerature from the
+ *       above mapping table
+ *
+ * A positive converted temperarure value will be returned on success,
+ * a negative errno will be returned in error cases.
+ */
+int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
+			  int raw)
+{
+	int i, delta_temp, delta_raw, temp;
+	struct acpi_lpat *lpat = lpat_table->lpat;
+
+	for (i = 0; i < lpat_table->lpat_count - 1; i++) {
+		if ((raw >= lpat[i].raw && raw <= lpat[i+1].raw) ||
+		    (raw <= lpat[i].raw && raw >= lpat[i+1].raw))
+			break;
+	}
+
+	if (i == lpat_table->lpat_count - 1)
+		return -ENOENT;
+
+	delta_temp = lpat[i+1].temp - lpat[i].temp;
+	delta_raw = lpat[i+1].raw - lpat[i].raw;
+	temp = lpat[i].temp + (raw - lpat[i].raw) * delta_temp / delta_raw;
+
+	return temp;
+}
+EXPORT_SYMBOL_GPL(acpi_lpat_raw_to_temp);
+
+/**
+ * acpi_lpat_temp_to_raw(): Return raw value from temperature through
+ * LPAT conversion table
+ *
+ * @lpat: the temperature_raw mapping table
+ * @temp: the temperature, used as a key to get the raw value from the
+ *        above mapping table
+ *
+ * A positive converted temperature value will be returned on success,
+ * a negative errno will be returned in error cases.
+ */
+int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
+			  int temp)
+{
+	int i, delta_temp, delta_raw, raw;
+	struct acpi_lpat *lpat = lpat_table->lpat;
+
+	for (i = 0; i < lpat_table->lpat_count - 1; i++) {
+		if (temp >= lpat[i].temp && temp <= lpat[i+1].temp)
+			break;
+	}
+
+	if (i ==  lpat_table->lpat_count - 1)
+		return -ENOENT;
+
+	delta_temp = lpat[i+1].temp - lpat[i].temp;
+	delta_raw = lpat[i+1].raw - lpat[i].raw;
+	raw = lpat[i].raw + (temp - lpat[i].temp) * delta_raw / delta_temp;
+
+	return raw;
+}
+EXPORT_SYMBOL_GPL(acpi_lpat_temp_to_raw);
+
+/**
+ * acpi_lpat_get_conversion_table(): Parse ACPI LPAT table if present.
+ *
+ * @handle: Handle to acpi device
+ *
+ * Parse LPAT table to a struct of type acpi_lpat_table. On success
+ * it returns a pointer to newly allocated table. This table must
+ * be freed by the caller when finished processing, using a call to
+ * acpi_lpat_free_conversion_table.
+ */
+struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(acpi_handle
+								  handle)
+{
+	struct acpi_lpat_conversion_table *lpat_table = NULL;
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj_p, *obj_e;
+	int *lpat, i;
+	acpi_status status;
+
+	status = acpi_evaluate_object(handle, "LPAT", NULL, &buffer);
+	if (ACPI_FAILURE(status))
+		return NULL;
+
+	obj_p = (union acpi_object *)buffer.pointer;
+	if (!obj_p || (obj_p->type != ACPI_TYPE_PACKAGE) ||
+	    (obj_p->package.count % 2) || (obj_p->package.count < 4))
+		goto out;
+
+	lpat = kcalloc(obj_p->package.count, sizeof(int), GFP_KERNEL);
+	if (!lpat)
+		goto out;
+
+	for (i = 0; i < obj_p->package.count; i++) {
+		obj_e = &obj_p->package.elements[i];
+		if (obj_e->type != ACPI_TYPE_INTEGER) {
+			kfree(lpat);
+			goto out;
+		}
+		lpat[i] = (s64)obj_e->integer.value;
+	}
+
+	lpat_table = kzalloc(sizeof(*lpat_table), GFP_KERNEL);
+	if (!lpat_table) {
+		kfree(lpat);
+		goto out;
+	}
+
+	lpat_table->lpat = (struct acpi_lpat *)lpat;
+	lpat_table->lpat_count = obj_p->package.count / 2;
+
+out:
+	kfree(buffer.pointer);
+	return lpat_table;
+}
+EXPORT_SYMBOL_GPL(acpi_lpat_get_conversion_table);
+
+/**
+ * acpi_lpat_free_conversion_table(): Free LPAT table.
+ *
+ * @lpat_table: the temperature_raw mapping table structure
+ *
+ * Frees the LPAT table previously allocated by a call to
+ * acpi_lpat_get_conversion_table.
+ */
+void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
+				     *lpat_table)
+{
+	if (lpat_table) {
+		kfree(lpat_table->lpat);
+		kfree(lpat_table);
+	}
+}
+EXPORT_SYMBOL_GPL(acpi_lpat_free_conversion_table);
+
+MODULE_LICENSE("GPL");
diff --git a/include/acpi/acpi_lpat.h b/include/acpi/acpi_lpat.h
new file mode 100644
index 0000000..da37e12
--- /dev/null
+++ b/include/acpi/acpi_lpat.h
@@ -0,0 +1,65 @@
+/*
+ * acpi_lpat.h - LPAT table processing functions
+ *
+ * Copyright (C) 2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#ifndef ACPI_LPAT_H
+#define ACPI_LPAT_H
+
+struct acpi_lpat {
+	int temp;
+	int raw;
+};
+
+struct acpi_lpat_conversion_table {
+	struct acpi_lpat *lpat;
+	int lpat_count;
+};
+
+#ifdef CONFIG_ACPI
+
+int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
+			  int raw);
+int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
+			  int temp);
+struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(acpi_handle
+								  handle);
+void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
+				     *lpat_table);
+
+#else
+static int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
+				 int raw)
+{
+	return 0;
+}
+
+static int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
+				 int temp)
+{
+	return 0;
+}
+
+static struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(
+							acpi_handle handle)
+{
+	return NULL;
+}
+
+static void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
+					    *lpat_table)
+{
+}
+
+#endif
+#endif
-- 
1.9.3

[PATCH 2/4] ACPI / PMIC: Use common LPAT table handling functions

[Srinivas Pandruvada]

The LPAT table processing functions from this modules are moved to a
standalone module with exported interface functions.
Using new interface functions in this module.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/acpi/pmic/intel_pmic.c | 133 ++++++-----------------------------------
 1 file changed, 18 insertions(+), 115 deletions(-)

diff --git a/drivers/acpi/pmic/intel_pmic.c b/drivers/acpi/pmic/intel_pmic.c
index a732e5d..bd772cd 100644
--- a/drivers/acpi/pmic/intel_pmic.c
+++ b/drivers/acpi/pmic/intel_pmic.c
@@ -16,20 +16,15 @@
 #include <linux/module.h>
 #include <linux/acpi.h>
 #include <linux/regmap.h>
+#include <acpi/acpi_lpat.h>
 #include "intel_pmic.h"
 
 #define PMIC_POWER_OPREGION_ID		0x8d
 #define PMIC_THERMAL_OPREGION_ID	0x8c
 
-struct acpi_lpat {
-	int temp;
-	int raw;
-};
-
 struct intel_pmic_opregion {
 	struct mutex lock;
-	struct acpi_lpat *lpat;
-	int lpat_count;
+	struct acpi_lpat_conversion_table *lpat_table;
 	struct regmap *regmap;
 	struct intel_pmic_opregion_data *data;
 };
@@ -50,105 +45,6 @@ static int pmic_get_reg_bit(int address, struct pmic_table *table,
 	return -ENOENT;
 }
 
-/**
- * raw_to_temp(): Return temperature from raw value through LPAT table
- *
- * @lpat: the temperature_raw mapping table
- * @count: the count of the above mapping table
- * @raw: the raw value, used as a key to get the temerature from the
- *       above mapping table
- *
- * A positive value will be returned on success, a negative errno will
- * be returned in error cases.
- */
-static int raw_to_temp(struct acpi_lpat *lpat, int count, int raw)
-{
-	int i, delta_temp, delta_raw, temp;
-
-	for (i = 0; i < count - 1; i++) {
-		if ((raw >= lpat[i].raw && raw <= lpat[i+1].raw) ||
-		    (raw <= lpat[i].raw && raw >= lpat[i+1].raw))
-			break;
-	}
-
-	if (i == count - 1)
-		return -ENOENT;
-
-	delta_temp = lpat[i+1].temp - lpat[i].temp;
-	delta_raw = lpat[i+1].raw - lpat[i].raw;
-	temp = lpat[i].temp + (raw - lpat[i].raw) * delta_temp / delta_raw;
-
-	return temp;
-}
-
-/**
- * temp_to_raw(): Return raw value from temperature through LPAT table
- *
- * @lpat: the temperature_raw mapping table
- * @count: the count of the above mapping table
- * @temp: the temperature, used as a key to get the raw value from the
- *        above mapping table
- *
- * A positive value will be returned on success, a negative errno will
- * be returned in error cases.
- */
-static int temp_to_raw(struct acpi_lpat *lpat, int count, int temp)
-{
-	int i, delta_temp, delta_raw, raw;
-
-	for (i = 0; i < count - 1; i++) {
-		if (temp >= lpat[i].temp && temp <= lpat[i+1].temp)
-			break;
-	}
-
-	if (i == count - 1)
-		return -ENOENT;
-
-	delta_temp = lpat[i+1].temp - lpat[i].temp;
-	delta_raw = lpat[i+1].raw - lpat[i].raw;
-	raw = lpat[i].raw + (temp - lpat[i].temp) * delta_raw / delta_temp;
-
-	return raw;
-}
-
-static void pmic_thermal_lpat(struct intel_pmic_opregion *opregion,
-			      acpi_handle handle, struct device *dev)
-{
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object *obj_p, *obj_e;
-	int *lpat, i;
-	acpi_status status;
-
-	status = acpi_evaluate_object(handle, "LPAT", NULL, &buffer);
-	if (ACPI_FAILURE(status))
-		return;
-
-	obj_p = (union acpi_object *)buffer.pointer;
-	if (!obj_p || (obj_p->type != ACPI_TYPE_PACKAGE) ||
-	    (obj_p->package.count % 2) || (obj_p->package.count < 4))
-		goto out;
-
-	lpat = devm_kmalloc(dev, sizeof(int) * obj_p->package.count,
-			    GFP_KERNEL);
-	if (!lpat)
-		goto out;
-
-	for (i = 0; i < obj_p->package.count; i++) {
-		obj_e = &obj_p->package.elements[i];
-		if (obj_e->type != ACPI_TYPE_INTEGER) {
-			devm_kfree(dev, lpat);
-			goto out;
-		}
-		lpat[i] = (s64)obj_e->integer.value;
-	}
-
-	opregion->lpat = (struct acpi_lpat *)lpat;
-	opregion->lpat_count = obj_p->package.count / 2;
-
-out:
-	kfree(buffer.pointer);
-}
-
 static acpi_status intel_pmic_power_handler(u32 function,
 		acpi_physical_address address, u32 bits, u64 *value64,
 		void *handler_context, void *region_context)
@@ -192,12 +88,12 @@ static int pmic_read_temp(struct intel_pmic_opregion *opregion,
 	if (raw_temp < 0)
 		return raw_temp;
 
-	if (!opregion->lpat) {
+	if (!opregion->lpat_table) {
 		*value = raw_temp;
 		return 0;
 	}
 
-	temp = raw_to_temp(opregion->lpat, opregion->lpat_count, raw_temp);
+	temp = acpi_lpat_raw_to_temp(opregion->lpat_table, raw_temp);
 	if (temp < 0)
 		return temp;
 
@@ -223,9 +119,8 @@ static int pmic_thermal_aux(struct intel_pmic_opregion *opregion, int reg,
 	if (!opregion->data->update_aux)
 		return -ENXIO;
 
-	if (opregion->lpat) {
-		raw_temp = temp_to_raw(opregion->lpat, opregion->lpat_count,
-				       *value);
+	if (opregion->lpat_table) {
+		raw_temp = acpi_lpat_temp_to_raw(opregion->lpat_table, *value);
 		if (raw_temp < 0)
 			return raw_temp;
 	} else {
@@ -314,6 +209,7 @@ int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle,
 {
 	acpi_status status;
 	struct intel_pmic_opregion *opregion;
+	int ret;
 
 	if (!dev || !regmap || !d)
 		return -EINVAL;
@@ -327,14 +223,16 @@ int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle,
 
 	mutex_init(&opregion->lock);
 	opregion->regmap = regmap;
-	pmic_thermal_lpat(opregion, handle, dev);
+	opregion->lpat_table = acpi_lpat_get_conversion_table(handle);
 
 	status = acpi_install_address_space_handler(handle,
 						    PMIC_POWER_OPREGION_ID,
 						    intel_pmic_power_handler,
 						    NULL, opregion);
-	if (ACPI_FAILURE(status))
-		return -ENODEV;
+	if (ACPI_FAILURE(status)) {
+		ret = -ENODEV;
+		goto out_error;
+	}
 
 	status = acpi_install_address_space_handler(handle,
 						    PMIC_THERMAL_OPREGION_ID,
@@ -343,11 +241,16 @@ int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle,
 	if (ACPI_FAILURE(status)) {
 		acpi_remove_address_space_handler(handle, PMIC_POWER_OPREGION_ID,
 						  intel_pmic_power_handler);
-		return -ENODEV;
+		ret = -ENODEV;
+		goto out_error;
 	}
 
 	opregion->data = d;
 	return 0;
+
+out_error:
+	acpi_lpat_free_conversion_table(opregion->lpat_table);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(intel_pmic_install_opregion_handler);
 
-- 
1.9.3

[PATCH 3/4] Thermal/int340x: LPAT conversion for temperature

[Srinivas Pandruvada]

When LPAT table is present, we need to convert raw temperature to
real temp using LPAT.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 .../thermal/int340x_thermal/int340x_thermal_zone.c   | 20 +++++++++++++++++---
 .../thermal/int340x_thermal/int340x_thermal_zone.h   |  3 +++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/thermal/int340x_thermal/int340x_thermal_zone.c b/drivers/thermal/int340x_thermal/int340x_thermal_zone.c
index 162e545..f88b088 100644
--- a/drivers/thermal/int340x_thermal/int340x_thermal_zone.c
+++ b/drivers/thermal/int340x_thermal/int340x_thermal_zone.c
@@ -33,8 +33,17 @@ static int int340x_thermal_get_zone_temp(struct thermal_zone_device *zone,
 	if (ACPI_FAILURE(status))
 		return -EIO;
 
-	/* _TMP returns the temperature in tenths of degrees Kelvin */
-	*temp = DECI_KELVIN_TO_MILLICELSIUS(tmp);
+	if (d->lpat_table) {
+		int conv_temp;
+
+		conv_temp = acpi_lpat_raw_to_temp(d->lpat_table, (int)tmp);
+		if (conv_temp < 0)
+			return conv_temp;
+
+		*temp = (unsigned long)conv_temp * 10;
+	} else
+		/* _TMP returns the temperature in tenths of degrees Kelvin */
+		*temp = DECI_KELVIN_TO_MILLICELSIUS(tmp);
 
 	return 0;
 }
@@ -227,6 +236,8 @@ struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *adev,
 		int34x_thermal_zone->act_trips[i].id = trip_cnt++;
 		int34x_thermal_zone->act_trips[i].valid = true;
 	}
+	int34x_thermal_zone->lpat_table = acpi_lpat_get_conversion_table(
+								adev->handle);
 
 	int34x_thermal_zone->zone = thermal_zone_device_register(
 						acpi_device_bid(adev),
@@ -237,11 +248,13 @@ struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *adev,
 						0, 0);
 	if (IS_ERR(int34x_thermal_zone->zone)) {
 		ret = PTR_ERR(int34x_thermal_zone->zone);
-		goto free_mem;
+		goto free_lpat;
 	}
 
 	return int34x_thermal_zone;
 
+free_lpat:
+	acpi_lpat_free_conversion_table(int34x_thermal_zone->lpat_table);
 free_mem:
 	kfree(int34x_thermal_zone);
 	return ERR_PTR(ret);
@@ -252,6 +265,7 @@ void int340x_thermal_zone_remove(struct int34x_thermal_zone
 				 *int34x_thermal_zone)
 {
 	thermal_zone_device_unregister(int34x_thermal_zone->zone);
+	acpi_lpat_free_conversion_table(int34x_thermal_zone->lpat_table);
 	kfree(int34x_thermal_zone);
 }
 EXPORT_SYMBOL_GPL(int340x_thermal_zone_remove);
diff --git a/drivers/thermal/int340x_thermal/int340x_thermal_zone.h b/drivers/thermal/int340x_thermal/int340x_thermal_zone.h
index 11f2f52..9f38ab7 100644
--- a/drivers/thermal/int340x_thermal/int340x_thermal_zone.h
+++ b/drivers/thermal/int340x_thermal/int340x_thermal_zone.h
@@ -16,6 +16,8 @@
 #ifndef __INT340X_THERMAL_ZONE_H__
 #define __INT340X_THERMAL_ZONE_H__
 
+#include <acpi/acpi_lpat.h>
+
 #define INT340X_THERMAL_MAX_ACT_TRIP_COUNT	10
 
 struct active_trip {
@@ -38,6 +40,7 @@ struct int34x_thermal_zone {
 	struct thermal_zone_device *zone;
 	struct thermal_zone_device_ops *override_ops;
 	void *priv_data;
+	struct acpi_lpat_conversion_table *lpat_table;
 };
 
 struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *,
-- 
1.9.3

[PATCH 4/4] Thermal/int340x/int3403: Support for thermistor and IR sensor

[Srinivas Pandruvada]

Added two more sensor types: Thermistor and IR sensor. Each of these
sensors have unique ptyp value.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 drivers/thermal/int340x_thermal/int3403_thermal.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/thermal/int340x_thermal/int3403_thermal.c b/drivers/thermal/int340x_thermal/int3403_thermal.c
index 50a7a08..2b5b140 100644
--- a/drivers/thermal/int340x_thermal/int3403_thermal.c
+++ b/drivers/thermal/int340x_thermal/int3403_thermal.c
@@ -24,6 +24,9 @@
 #define INT3403_TYPE_SENSOR		0x03
 #define INT3403_TYPE_CHARGER		0x0B
 #define INT3403_TYPE_BATTERY		0x0C
+#define INT3403_TYPE_SENSOR_THERMISTOR	0x12
+#define INT3403_TYPE_SENSOR_IR		0x13
+
 #define INT3403_PERF_CHANGED_EVENT	0x80
 #define INT3403_THERMAL_EVENT		0x90
 
@@ -238,6 +241,8 @@ static int int3403_add(struct platform_device *pdev)
 	platform_set_drvdata(pdev, priv);
 	switch (priv->type) {
 	case INT3403_TYPE_SENSOR:
+	case INT3403_TYPE_SENSOR_THERMISTOR:
+	case INT3403_TYPE_SENSOR_IR:
 		result = int3403_sensor_add(priv);
 		break;
 	case INT3403_TYPE_CHARGER:
@@ -262,6 +267,8 @@ static int int3403_remove(struct platform_device *pdev)
 
 	switch (priv->type) {
 	case INT3403_TYPE_SENSOR:
+	case INT3403_TYPE_SENSOR_THERMISTOR:
+	case INT3403_TYPE_SENSOR_IR:
 		int3403_sensor_remove(priv);
 		break;
 	case INT3403_TYPE_CHARGER:
-- 
1.9.3

Re: [PATCH 1/4] ACPI / LPAT: Common table processing functions

[Rafael J. Wysocki]

On Wednesday, January 28, 2015 11:56:46 AM Srinivas Pandruvada wrote:
> Since LPAT table processing is also required for other thermal drivers,
> moved LPAT table related functions from intel PMIC driver (intel_pmic.c)
> to a stand alonge module with exported interfaces.
> In this way there will be no code duplication.
> 
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/Makefile    |   1 +
>  drivers/acpi/acpi_lpat.c | 161 +++++++++++++++++++++++++++++++++++++++++++++++
>  include/acpi/acpi_lpat.h |  65 +++++++++++++++++++
>  3 files changed, 227 insertions(+)
>  create mode 100644 drivers/acpi/acpi_lpat.c
>  create mode 100644 include/acpi/acpi_lpat.h
> 
> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
> index f74317c..d22253d 100644
> --- a/drivers/acpi/Makefile
> +++ b/drivers/acpi/Makefile
> @@ -55,6 +55,7 @@ acpi-$(CONFIG_ACPI_PROCFS_POWER) += cm_sbs.o
>  ifdef CONFIG_ACPI_VIDEO
>  acpi-y				+= video_detect.o
>  endif
> +acpi-y				+= acpi_lpat.o
>  
>  # These are (potentially) separate modules
>  
> diff --git a/drivers/acpi/acpi_lpat.c b/drivers/acpi/acpi_lpat.c
> new file mode 100644
> index 0000000..feb61c1
> --- /dev/null
> +++ b/drivers/acpi/acpi_lpat.c
> @@ -0,0 +1,161 @@
> +/*
> + * acpi_lpat.c - LPAT table processing functions
> + *
> + * Copyright (C) 2015 Intel Corporation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License version
> + * 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that 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.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/acpi.h>
> +#include <acpi/acpi_lpat.h>
> +
> +/**
> + * acpi_lpat_raw_to_temp(): Return temperature from raw value through
> + * LPAT conversion table
> + *
> + * @lpat_table: the temperature_raw mapping table structure
> + * @raw: the raw value, used as a key to get the temerature from the
> + *       above mapping table
> + *
> + * A positive converted temperarure value will be returned on success,
> + * a negative errno will be returned in error cases.
> + */
> +int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
> +			  int raw)
> +{
> +	int i, delta_temp, delta_raw, temp;
> +	struct acpi_lpat *lpat = lpat_table->lpat;
> +
> +	for (i = 0; i < lpat_table->lpat_count - 1; i++) {
> +		if ((raw >= lpat[i].raw && raw <= lpat[i+1].raw) ||
> +		    (raw <= lpat[i].raw && raw >= lpat[i+1].raw))
> +			break;
> +	}
> +
> +	if (i == lpat_table->lpat_count - 1)
> +		return -ENOENT;
> +
> +	delta_temp = lpat[i+1].temp - lpat[i].temp;
> +	delta_raw = lpat[i+1].raw - lpat[i].raw;
> +	temp = lpat[i].temp + (raw - lpat[i].raw) * delta_temp / delta_raw;
> +
> +	return temp;
> +}
> +EXPORT_SYMBOL_GPL(acpi_lpat_raw_to_temp);
> +
> +/**
> + * acpi_lpat_temp_to_raw(): Return raw value from temperature through
> + * LPAT conversion table
> + *
> + * @lpat: the temperature_raw mapping table
> + * @temp: the temperature, used as a key to get the raw value from the
> + *        above mapping table
> + *
> + * A positive converted temperature value will be returned on success,
> + * a negative errno will be returned in error cases.
> + */
> +int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
> +			  int temp)
> +{
> +	int i, delta_temp, delta_raw, raw;
> +	struct acpi_lpat *lpat = lpat_table->lpat;
> +
> +	for (i = 0; i < lpat_table->lpat_count - 1; i++) {
> +		if (temp >= lpat[i].temp && temp <= lpat[i+1].temp)
> +			break;
> +	}
> +
> +	if (i ==  lpat_table->lpat_count - 1)
> +		return -ENOENT;
> +
> +	delta_temp = lpat[i+1].temp - lpat[i].temp;
> +	delta_raw = lpat[i+1].raw - lpat[i].raw;
> +	raw = lpat[i].raw + (temp - lpat[i].temp) * delta_raw / delta_temp;
> +
> +	return raw;
> +}
> +EXPORT_SYMBOL_GPL(acpi_lpat_temp_to_raw);
> +
> +/**
> + * acpi_lpat_get_conversion_table(): Parse ACPI LPAT table if present.
> + *
> + * @handle: Handle to acpi device
> + *
> + * Parse LPAT table to a struct of type acpi_lpat_table. On success
> + * it returns a pointer to newly allocated table. This table must
> + * be freed by the caller when finished processing, using a call to
> + * acpi_lpat_free_conversion_table.
> + */
> +struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(acpi_handle
> +								  handle)
> +{
> +	struct acpi_lpat_conversion_table *lpat_table = NULL;
> +	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
> +	union acpi_object *obj_p, *obj_e;
> +	int *lpat, i;
> +	acpi_status status;
> +
> +	status = acpi_evaluate_object(handle, "LPAT", NULL, &buffer);
> +	if (ACPI_FAILURE(status))
> +		return NULL;
> +
> +	obj_p = (union acpi_object *)buffer.pointer;
> +	if (!obj_p || (obj_p->type != ACPI_TYPE_PACKAGE) ||
> +	    (obj_p->package.count % 2) || (obj_p->package.count < 4))
> +		goto out;
> +
> +	lpat = kcalloc(obj_p->package.count, sizeof(int), GFP_KERNEL);
> +	if (!lpat)
> +		goto out;
> +
> +	for (i = 0; i < obj_p->package.count; i++) {
> +		obj_e = &obj_p->package.elements[i];
> +		if (obj_e->type != ACPI_TYPE_INTEGER) {
> +			kfree(lpat);
> +			goto out;
> +		}
> +		lpat[i] = (s64)obj_e->integer.value;
> +	}
> +
> +	lpat_table = kzalloc(sizeof(*lpat_table), GFP_KERNEL);
> +	if (!lpat_table) {
> +		kfree(lpat);
> +		goto out;
> +	}
> +
> +	lpat_table->lpat = (struct acpi_lpat *)lpat;
> +	lpat_table->lpat_count = obj_p->package.count / 2;
> +
> +out:
> +	kfree(buffer.pointer);
> +	return lpat_table;
> +}
> +EXPORT_SYMBOL_GPL(acpi_lpat_get_conversion_table);
> +
> +/**
> + * acpi_lpat_free_conversion_table(): Free LPAT table.
> + *
> + * @lpat_table: the temperature_raw mapping table structure
> + *
> + * Frees the LPAT table previously allocated by a call to
> + * acpi_lpat_get_conversion_table.
> + */
> +void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
> +				     *lpat_table)
> +{
> +	if (lpat_table) {
> +		kfree(lpat_table->lpat);
> +		kfree(lpat_table);
> +	}
> +}
> +EXPORT_SYMBOL_GPL(acpi_lpat_free_conversion_table);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/include/acpi/acpi_lpat.h b/include/acpi/acpi_lpat.h
> new file mode 100644
> index 0000000..da37e12
> --- /dev/null
> +++ b/include/acpi/acpi_lpat.h
> @@ -0,0 +1,65 @@
> +/*
> + * acpi_lpat.h - LPAT table processing functions
> + *
> + * Copyright (C) 2015 Intel Corporation. All rights reserved.
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License version
> + * 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that 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.
> + */
> +
> +#ifndef ACPI_LPAT_H
> +#define ACPI_LPAT_H
> +
> +struct acpi_lpat {
> +	int temp;
> +	int raw;
> +};
> +
> +struct acpi_lpat_conversion_table {
> +	struct acpi_lpat *lpat;
> +	int lpat_count;
> +};
> +
> +#ifdef CONFIG_ACPI
> +
> +int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
> +			  int raw);
> +int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
> +			  int temp);
> +struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(acpi_handle
> +								  handle);
> +void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
> +				     *lpat_table);
> +
> +#else
> +static int acpi_lpat_raw_to_temp(struct acpi_lpat_conversion_table *lpat_table,
> +				 int raw)
> +{
> +	return 0;
> +}
> +
> +static int acpi_lpat_temp_to_raw(struct acpi_lpat_conversion_table *lpat_table,
> +				 int temp)
> +{
> +	return 0;
> +}
> +
> +static struct acpi_lpat_conversion_table *acpi_lpat_get_conversion_table(
> +							acpi_handle handle)
> +{
> +	return NULL;
> +}
> +
> +static void acpi_lpat_free_conversion_table(struct acpi_lpat_conversion_table
> +					    *lpat_table)
> +{
> +}
> +
> +#endif
> +#endif
> 

-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.