power: pm8921-bms: add capacitive resistance
The current code only accounts for the series resistance via a lookup
table. Add a configurable parameter to account for capacitive resistance.
Change-Id: I6a844b51970a6bdf40cfc1340fa31f580efc1c9e
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
diff --git a/arch/arm/mach-msm/bms-batterydata-desay.c b/arch/arm/mach-msm/bms-batterydata-desay.c
index 5b72a3f..dd3f346 100644
--- a/arch/arm/mach-msm/bms-batterydata-desay.c
+++ b/arch/arm/mach-msm/bms-batterydata-desay.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2011-2013, The Linux Foundation. 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 and
@@ -83,4 +83,5 @@
.pc_temp_ocv_lut = &desay_5200_pc_temp_ocv,
.pc_sf_lut = &desay_5200_pc_sf,
.default_rbatt_mohm = 156,
+ .rbatt_capacitive_mohm = 50,
};
diff --git a/arch/arm/mach-msm/bms-batterydata.c b/arch/arm/mach-msm/bms-batterydata.c
index 824cf6b..0c39df6 100644
--- a/arch/arm/mach-msm/bms-batterydata.c
+++ b/arch/arm/mach-msm/bms-batterydata.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2011-2012, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2011-2013, The Linux Foundation. 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 and
@@ -105,4 +105,5 @@
.pc_temp_ocv_lut = &pc_temp_ocv,
.rbatt_sf_lut = &rbatt_sf,
.default_rbatt_mohm = 236,
+ .rbatt_capacitive_mohm = 50,
};
diff --git a/drivers/power/pm8921-bms.c b/drivers/power/pm8921-bms.c
index 82d58ef..72c763e 100644
--- a/drivers/power/pm8921-bms.c
+++ b/drivers/power/pm8921-bms.c
@@ -136,6 +136,7 @@
int amux_2_trim_delta;
uint16_t prev_last_good_ocv_raw;
int rconn_mohm;
+ int rbatt_capacitive_mohm;
struct mutex last_ocv_uv_mutex;
int last_ocv_uv;
int last_ocv_temp_decidegc;
@@ -847,8 +848,8 @@
{
int ibat_ua, vbat_uv, ocv_est_uv;
int rc;
-
- int rbatt_mohm = chip->default_rbatt_mohm + chip->rconn_mohm;
+ int rbatt_mohm = chip->default_rbatt_mohm + chip->rconn_mohm
+ + chip->rbatt_capacitive_mohm;
rc = pm8921_bms_get_simultaneous_battery_voltage_and_current(
&ibat_ua,
@@ -917,7 +918,10 @@
rc = pm8921_bms_get_simultaneous_battery_voltage_and_current(
&ibat_ua,
&vbat_uv);
-
+ /*
+ * don't include rbatt and rbatt_capacitve since we expect this to
+ * be used with a fake battery which does not have internal resistnaces
+ */
ocv_est_uv = vbat_uv + (ibat_ua * the_chip->rconn_mohm) / 1000;
pr_debug("forcing ocv to be %d due to bms reset mode\n", ocv_est_uv);
the_chip->last_ocv_uv = ocv_est_uv;
@@ -1072,6 +1076,10 @@
pr_debug("adding rconn_mohm = %d rbatt = %d\n",
the_chip->rconn_mohm, rbatt);
+ rbatt += the_chip->rbatt_capacitive_mohm;
+ pr_debug("adding rbatt_capacitive_mohm = %d rbatt = %d\n",
+ the_chip->rbatt_capacitive_mohm, rbatt);
+
if (is_between(20, 10, soc_rbatt))
rbatt = rbatt
+ ((20 - soc_rbatt) * chip->delta_rbatt_mohm) / 10;
@@ -2869,6 +2877,8 @@
chip->default_rbatt_mohm
= palladium_1500_data.default_rbatt_mohm;
chip->delta_rbatt_mohm = palladium_1500_data.delta_rbatt_mohm;
+ chip->rbatt_capacitive_mohm
+ = palladium_1500_data.rbatt_capacitive_mohm;
return 0;
desay:
chip->fcc = desay_5200_data.fcc;
@@ -2878,6 +2888,8 @@
chip->rbatt_sf_lut = desay_5200_data.rbatt_sf_lut;
chip->default_rbatt_mohm = desay_5200_data.default_rbatt_mohm;
chip->delta_rbatt_mohm = desay_5200_data.delta_rbatt_mohm;
+ chip->rbatt_capacitive_mohm
+ = desay_5200_data.rbatt_capacitive_mohm;
return 0;
}
diff --git a/include/linux/mfd/pm8xxx/batterydata-lib.h b/include/linux/mfd/pm8xxx/batterydata-lib.h
index 5ff1cfb..f27ceca 100644
--- a/include/linux/mfd/pm8xxx/batterydata-lib.h
+++ b/include/linux/mfd/pm8xxx/batterydata-lib.h
@@ -89,6 +89,8 @@
* readings from bms are not available.
* @delta_rbatt_mohm: the resistance to be added towards lower soc to
* compensate for battery capacitance.
+ * @rbatt_capacitve_mohm: the resistance to be added to compensate for
+ * battery capacitance
*/
struct bms_battery_data {
@@ -100,6 +102,7 @@
struct sf_lut *rbatt_sf_lut;
int default_rbatt_mohm;
int delta_rbatt_mohm;
+ int rbatt_capacitive_mohm;
};
#if defined(CONFIG_PM8921_BMS) || \