---
ChangeLog v3->v4:
- Fix the code to really provide the same x index for both
   datapoints at the end of the table. Thanks again Baolin!
ChangeLog v2->v3:
- Actually implement the code as I say. Missed one occurence.
ChangeLog v1->v2:
- Break the table loop at table_len - 1 so we don't index
   past the end of the table. (Thanks Baolin!)

Chunyan: The sc27xx fuel gauge seems to be the only driver
using this, so it'd be great if you could test this to make
sure it works as intended.
---
  drivers/power/supply/power_supply_core.c | 61 ++++++++++++------------
  1 file changed, 31 insertions(+), 30 deletions(-)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index fc12a4f407f4..2907b84ceea9 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c

@@ -21,6 +21,7 @@
  #include <linux/power_supply.h>
  #include <linux/property.h>
  #include <linux/thermal.h>
+#include <linux/fixp-arith.h>
  #include "power_supply.h"
  
  /* exported for the APM Power driver, APM emulation */

@@ -783,26 +784,25 @@ EXPORT_SYMBOL_GPL(power_supply_put_battery_info);
  int power_supply_temp2resist_simple(struct power_supply_resistance_temp_table *table,
  				    int table_len, int temp)
  {
-	int i, resist;
+	int i, high, low;
  
-	for (i = 0; i < table_len; i++)
+	/* Break loop at table_len - 1 because that is the highest index */
+	for (i = 0; i < table_len - 1; i++)
  		if (temp > table[i].temp)
  			break;
  
-	if (i > 0 && i < table_len) {
-		int tmp;
-
-		tmp = (table[i - 1].resistance - table[i].resistance) *
-			(temp - table[i].temp);
-		tmp /= table[i - 1].temp - table[i].temp;
-		resist = tmp + table[i].resistance;
-	} else if (i == 0) {
-		resist = table[0].resistance;
-	} else {
-		resist = table[table_len - 1].resistance;
-	}
-
-	return resist;
+	/* The library function will deal with high == low */
+	if ((i == 0) || (i == (table_len - 1)))
+		high = i;
+	else
+		high = i - 1;
+	low = i;
+
+	return fixp_linear_interpolate(table[low].temp,
+				       table[low].resistance,
+				       table[high].temp,
+				       table[high].resistance,
+				       temp);
  }
  EXPORT_SYMBOL_GPL(power_supply_temp2resist_simple);
  

@@ -821,24 +821,25 @@ EXPORT_SYMBOL_GPL(power_supply_temp2resist_simple);
  int power_supply_ocv2cap_simple(struct power_supply_battery_ocv_table *table,
  				int table_len, int ocv)
  {
-	int i, cap, tmp;
+	int i, high, low;
  
-	for (i = 0; i < table_len; i++)
+	/* Break loop at table_len - 1 because that is the highest index */
+	for (i = 0; i < table_len - 1; i++)
  		if (ocv > table[i].ocv)
  			break;
  
-	if (i > 0 && i < table_len) {
-		tmp = (table[i - 1].capacity - table[i].capacity) *
-			(ocv - table[i].ocv);
-		tmp /= table[i - 1].ocv - table[i].ocv;
-		cap = tmp + table[i].capacity;
-	} else if (i == 0) {
-		cap = table[0].capacity;
-	} else {
-		cap = table[table_len - 1].capacity;
-	}
-
-	return cap;
+	/* The library function will deal with high == low */
+	if ((i == 0) || (i == (table_len - 1)))
+		high = i - 1;
+	else
+		high = i; /* i.e. i == 0 */
+	low = i;
+
+	return fixp_linear_interpolate(table[low].ocv,
+				       table[low].capacity,
+				       table[high].ocv,
+				       table[high].capacity,
+				       ocv);
  }
  EXPORT_SYMBOL_GPL(power_supply_ocv2cap_simple);