Commit 67acb291 authored by Linus Walleij's avatar Linus Walleij Committed by Sebastian Reichel
Browse files

power: supply: ab8500: Standardize temp res lookup 



The lookup from battery temperature to internal resistance was
using its own format. Rewrite this to use the table inside
struct power_supply_battery_info:s resist_table.

The supplied resistance table has to be rewritten to express
the resistance in percent of the factory resistance as a
side effect.

We can then rely on the library function
power_supply_temp2resist_simple() to interpolate the internal
resistance percent from the temperature.

Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
parent bc6e0287

drivers/power/supply/ab8500-bm.h

+0 −15
Original line number Diff line number Diff line
@@ -379,8 +379,6 @@ struct ab8500_maxim_parameters { 
 * @r_to_t_tbl:			table containing resistance to temp points

 * @n_v_cap_tbl_elements:	number of elements in v_to_cap_tbl

 * @v_to_cap_tbl:		Voltage to capacity (in %) table

 * @n_batres_tbl_elements	number of elements in the batres_tbl

 * @batres_tbl			battery internal resistance vs temperature table

 */

struct ab8500_battery_type {

	int resis_high;
@@ -397,8 +395,6 @@ struct ab8500_battery_type { 
	const struct ab8500_res_to_temp *r_to_t_tbl;

	int n_v_cap_tbl_elements;

	const struct ab8500_v_to_cap *v_to_cap_tbl;

	int n_batres_tbl_elements;

	const struct batres_vs_temp *batres_tbl;

};



/**
@@ -502,17 +498,6 @@ struct res_to_temp { 
	int resist;

};



/**

 * struct batres_vs_temp - defines one point in a temp vs battery internal

 * resistance curve.

 * @temp:			battery pack temperature in Celsius

 * @resist:			battery internal reistance in mOhm

 */

struct batres_vs_temp {

	int temp;

	int resist;

};



/* Forward declaration */

struct ab8500_fg;

drivers/power/supply/ab8500_bmdata.c

+19 −12
Original line number Diff line number Diff line
@@ -67,16 +67,17 @@ static const struct ab8500_res_to_temp temp_tbl[] = { 


/*

 * Note that the batres_vs_temp table must be strictly sorted by falling

 * temperature values to work.

 * temperature values to work. Factory resistance is 300 mOhm and the

 * resistance values to the right are percentages of 300 mOhm.

 */

static const struct batres_vs_temp temp_to_batres_tbl_thermistor[] = {

	{ 40, 120},

	{ 30, 135},

	{ 20, 165},

	{ 10, 230},

	{ 00, 325},

	{-10, 445},

	{-20, 595},

static struct power_supply_resistance_temp_table temp_to_batres_tbl_thermistor[] = {

	{ .temp = 40, .resistance = 40 /* 120 mOhm */ },

	{ .temp = 30, .resistance = 45 /* 135 mOhm */ },

	{ .temp = 20, .resistance = 55 /* 165 mOhm */ },

	{ .temp = 10, .resistance = 77 /* 230 mOhm */ },

	{ .temp = 00, .resistance = 108 /* 325 mOhm */ },

	{ .temp = -10, .resistance = 158 /* 445 mOhm */ },

	{ .temp = -20, .resistance = 198 /* 595 mOhm */ },

};



/* Default battery type for reference designs is the unknown type */
@@ -95,8 +96,6 @@ static struct ab8500_battery_type bat_type_thermistor_unknown = { 
	.r_to_t_tbl = temp_tbl,

	.n_v_cap_tbl_elements = ARRAY_SIZE(cap_tbl),

	.v_to_cap_tbl = cap_tbl,

	.n_batres_tbl_elements = ARRAY_SIZE(temp_to_batres_tbl_thermistor),

	.batres_tbl = temp_to_batres_tbl_thermistor,

};



static const struct ab8500_bm_capacity_levels cap_levels = {
@@ -209,8 +208,16 @@ int ab8500_bm_of_probe(struct power_supply *psy, 
		/* Charging stops when we drop below this current */

		bi->charge_term_current_ua = 200000;



	if (bi->factory_internal_resistance_uohm < 0)

	/*

	 * Internal resistance and factory resistance are tightly coupled

	 * so both MUST be defined or we fall back to defaults.

	 */

	if ((bi->factory_internal_resistance_uohm < 0) ||

	    !bi->resist_table) {

		bi->factory_internal_resistance_uohm = 300000;

		bi->resist_table = temp_to_batres_tbl_thermistor;

		bi->resist_table_size = ARRAY_SIZE(temp_to_batres_tbl_thermistor);

	}



	if (bi->temp_min == INT_MIN)

		bi->temp_min = AB8500_TEMP_UNDER;

drivers/power/supply/ab8500_fg.c

+19 −28
Original line number Diff line number Diff line
@@ -901,44 +901,35 @@ static int ab8500_fg_uncomp_volt_to_capacity(struct ab8500_fg *di) 
 * @di:		pointer to the ab8500_fg structure

 *

 * Returns battery inner resistance added with the fuel gauge resistor value

 * to get the total resistance in the whole link from gnd to bat+ node.

 * to get the total resistance in the whole link from gnd to bat+ node

 * in milliohm.

 */

static int ab8500_fg_battery_resistance(struct ab8500_fg *di)

{

	int i, tbl_size;

	const struct batres_vs_temp *tbl;

	int resist = 0;



	tbl = di->bm->bat_type->batres_tbl;

	tbl_size = di->bm->bat_type->n_batres_tbl_elements;



	for (i = 0; i < tbl_size; ++i) {

		if (di->bat_temp / 10 > tbl[i].temp)

			break;

	}

	struct power_supply_battery_info *bi = &di->bm->bi;

	int resistance_percent = 0;

	int resistance;



	if ((i > 0) && (i < tbl_size)) {

		resist = fixp_linear_interpolate(

			tbl[i].temp,

			tbl[i].resist,

			tbl[i-1].temp,

			tbl[i-1].resist,

	resistance_percent = power_supply_temp2resist_simple(bi->resist_table,

						 bi->resist_table_size,

						 di->bat_temp / 10);

	} else if (i == 0) {

		resist = tbl[0].resist;

	} else {

		resist = tbl[tbl_size - 1].resist;

	}

	/*

	 * We get a percentage of factory resistance here so first get

	 * the factory resistance in milliohms then calculate how much

	 * resistance we have at this temperature.

	 */

	resistance = (bi->factory_internal_resistance_uohm / 1000);

	resistance = resistance * resistance_percent / 100;



	dev_dbg(di->dev, "%s Temp: %d battery internal resistance: %d"

	    " fg resistance %d, total: %d (mOhm)\n",

		__func__, di->bat_temp, resist, di->bm->fg_res / 10,

		(di->bm->fg_res / 10) + resist);

		__func__, di->bat_temp, resistance, di->bm->fg_res / 10,

		(di->bm->fg_res / 10) + resistance);



	/* fg_res variable is in 0.1mOhm */

	resist += di->bm->fg_res / 10;

	resistance += di->bm->fg_res / 10;



	return resist;

	return resistance;

}



/**