power: ab8500_bm: Removal of maintenance charging

This patch makes it possible to remove the maintenance A and B
charging states and replaces them with a state that restarts the
charging when the battery voltage level dropped below a certain
level. The maintenance charging can now be turned of by setting
a flag in the board configuration.

ST-Ericsson Linux Next: -
ST-Ericsson ID: CR333019
ST-Ericsson FOSS-OUT ID: Trivial

Change-Id: Ie5e8ab20a3b57a1028d544371b10ffbb1fd77660
Signed-off-by: Kalle Komierowski <kalle.komierowski@gmail.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/19916
Reviewed-by: Johan GARDSMARK <johan.gardsmark@stericsson.com>
Reviewed-by: Johan PALSSON <johan.palsson@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Tested-by: Karl KOMIEROWSKI <karl.komierowski@stericsson.com>

4 files changed, 67 insertions, 5 deletions

diff --git a/arch/arm/mach-ux500/board-mop500-bm.c b/arch/arm/mach-ux500/board-mop500-bm.c
index 945964f3300..66ced8e088e 100644
--- a/arch/arm/mach-ux500/board-mop500-bm.c
+++ b/arch/arm/mach-ux500/board-mop500-bm.c
@@ -160,6 +160,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3700,
 		.termination_vol = 4050,
 		.termination_curr = 200,
+		.recharge_vol = 3990,
 		.normal_cur_lvl = 400,
 		.normal_vol_lvl = 4100,
 		.maint_a_cur_lvl = 400,
@@ -186,6 +187,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3600,
 		.termination_vol = 4150,
 		.termination_curr = 80,
+		.recharge_vol = 4130,
 		.normal_cur_lvl = 700,
 		.normal_vol_lvl = 4200,
 		.maint_a_cur_lvl = 600,
@@ -211,6 +213,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3600,
 		.termination_vol = 4150,
 		.termination_curr = 80,
+		.recharge_vol = 4130,
 		.normal_cur_lvl = 700,
 		.normal_vol_lvl = 4200,
 		.maint_a_cur_lvl = 600,
@@ -241,6 +244,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3700,
 		.termination_vol = 4150,
 		.termination_curr = 100,
+		.recharge_vol = 4130,
 		.normal_cur_lvl = 700,
 		.normal_vol_lvl = 4200,
 		.maint_a_cur_lvl = 600,
@@ -265,6 +269,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3700,
 		.termination_vol = 4150,
 		.termination_curr = 100,
+		.recharge_vol = 4130,
 		.normal_cur_lvl = 700,
 		.normal_vol_lvl = 4200,
 		.maint_a_cur_lvl = 600,
@@ -289,6 +294,7 @@ static const struct battery_type bat_type[] = {
 		.nominal_voltage = 3700,
 		.termination_vol = 4150,
 		.termination_curr = 100,
+		.recharge_vol = 4130,
 		.normal_cur_lvl = 700,
 		.normal_vol_lvl = 4200,
 		.maint_a_cur_lvl = 600,
@@ -390,6 +396,7 @@ struct ab8500_bm_data ab8500_bm_data = {
 	.usb_safety_tmr_h	= 4,
 	.bkup_bat_v		= BUP_VCH_SEL_2P6V,
 	.bkup_bat_i		= BUP_ICH_SEL_150UA,
+	.no_maintenance		= false,
 #ifdef CONFIG_AB8500_BATTERY_THERM_ON_BATCTRL
 	.adc_therm		= ADC_THERM_BATCTRL,
 #else
diff --git a/drivers/power/ab8500_chargalg.c b/drivers/power/ab8500_chargalg.c
index 788d81aa7cd..cb56c67475c 100644
--- a/drivers/power/ab8500_chargalg.c
+++ b/drivers/power/ab8500_chargalg.c
@@ -30,6 +30,9 @@
 /* End-of-charge criteria counter */
 #define EOC_COND_CNT			10
 
+/* Recharge criteria counter */
+#define RCH_COND_CNT			3
+
 #define to_ab8500_chargalg_device_info(x) container_of((x), \
 	struct ab8500_chargalg, chargalg_psy);
 
@@ -80,6 +83,8 @@ enum ab8500_chargalg_states {
 	STATE_HW_TEMP_PROTECT,
 	STATE_NORMAL_INIT,
 	STATE_NORMAL,
+	STATE_WAIT_FOR_RECHARGE_INIT,
+	STATE_WAIT_FOR_RECHARGE,
 	STATE_MAINTENANCE_A_INIT,
 	STATE_MAINTENANCE_A,
 	STATE_MAINTENANCE_B_INIT,
@@ -109,6 +114,8 @@ static const char *states[] = {
 	"HW_TEMP_PROTECT",
 	"NORMAL_INIT",
 	"NORMAL",
+	"WAIT_FOR_RECHARGE_INIT",
+	"WAIT_FOR_RECHARGE",
 	"MAINTENANCE_A_INIT",
 	"MAINTENANCE_A",
 	"MAINTENANCE_B_INIT",
@@ -186,6 +193,7 @@ enum maxim_ret {
  * @dev:		pointer to the structure device
  * @charge_status:	battery operating status
  * @eoc_cnt:		counter used to determine end-of_charge
+ * @rch_cnt:		counter used to determine start of recharge
  * @maintenance_chg:	indicate if maintenance charge is active
  * @t_hyst_norm		temperature hysteresis when the temperature has	been
  *			over or under normal limits
@@ -214,6 +222,7 @@ struct ab8500_chargalg {
 	struct device *dev;
 	int charge_status;
 	int eoc_cnt;
+	int rch_cnt;
 	bool maintenance_chg;
 	int t_hyst_norm;
 	int t_hyst_lowhigh;
@@ -569,6 +578,26 @@ static void ab8500_chargalg_stop_charging(struct ab8500_chargalg *di)
 }
 
 /**
+ * ab8500_chargalg_hold_charging() - Pauses charging
+ * @di:		pointer to the ab8500_chargalg structure
+ *
+ * This function is called in the case where maintenance charging has been
+ * disabled and instead a battery voltage mode is entered to check when the
+ * battery voltage has reached a certain recharge voltage
+ */
+static void ab8500_chargalg_hold_charging(struct ab8500_chargalg *di)
+{
+	ab8500_chargalg_ac_en(di, false, 0, 0);
+	ab8500_chargalg_usb_en(di, false, 0, 0);
+	ab8500_chargalg_stop_safety_timer(di);
+	ab8500_chargalg_stop_maintenance_timer(di);
+	di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
+	di->maintenance_chg = false;
+	cancel_delayed_work(&di->chargalg_wd_work);
+	power_supply_changed(&di->chargalg_psy);
+}
+
+/**
  * ab8500_chargalg_start_charging() - Start the charger
  * @di:		pointer to the ab8500_chargalg structure
  * @vset:	requested charger output voltage
@@ -1384,11 +1413,31 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 
 	case STATE_NORMAL:
 		handle_maxim_chg_curr(di);
-
 		if (di->charge_status == POWER_SUPPLY_STATUS_FULL &&
-				di->maintenance_chg)
-			ab8500_chargalg_state_to(di, STATE_MAINTENANCE_A_INIT);
+			di->maintenance_chg) {
+			if (di->bat->no_maintenance)
+				ab8500_chargalg_state_to(di,
+					STATE_WAIT_FOR_RECHARGE_INIT);
+			else
+				ab8500_chargalg_state_to(di,
+					STATE_MAINTENANCE_A_INIT);
+		}
+		break;
 
+	/* This state will be used when the maintenance state is disabled */
+	case STATE_WAIT_FOR_RECHARGE_INIT:
+		ab8500_chargalg_hold_charging(di);
+		ab8500_chargalg_state_to(di, STATE_WAIT_FOR_RECHARGE);
+		di->rch_cnt = RCH_COND_CNT;
+		/* Intentional fallthrough */
+
+	case STATE_WAIT_FOR_RECHARGE:
+		if (di->batt_data.volt <=
+			di->bat->bat_type[di->bat->batt_id].recharge_vol) {
+			if (di->rch_cnt-- == 0)
+				ab8500_chargalg_state_to(di, STATE_NORMAL_INIT);
+		} else
+			di->rch_cnt = RCH_COND_CNT;
 		break;
 
 	case STATE_MAINTENANCE_A_INIT:
diff --git a/drivers/power/ab8500_fg.c b/drivers/power/ab8500_fg.c
index a42ce95d48f..8af5216b90b 100644
--- a/drivers/power/ab8500_fg.c
+++ b/drivers/power/ab8500_fg.c
@@ -590,8 +590,7 @@ static void ab8500_fg_acc_cur_work(struct work_struct *work)
 
 	mutex_unlock(&di->cc_lock);
 
-	queue_work(di->fg_wq,
-		&di->fg_work);
+	queue_work(di->fg_wq, &di->fg_work);
 
 	return;
 exit:
diff --git a/include/linux/mfd/ab8500/bm.h b/include/linux/mfd/ab8500/bm.h
index 068b63a93ce..2ca4d8779cb 100644
--- a/include/linux/mfd/ab8500/bm.h
+++ b/include/linux/mfd/ab8500/bm.h
@@ -312,6 +312,10 @@ struct ab8500_maxim_parameters {
  * @charge_full_design:		Maximum battery capacity in mAh
  * @nominal_voltage:		Nominal voltage of the battery in mV
  * @termination_vol:		max voltage upto which battery can be charged
+ * @termination_curr		battery charging termination current in mA
+ * @recharge_vol		battery voltage limit that will trigger a new
+ *				full charging cycle in the case where maintenan-
+ *				-ce charging has been disabled
  * @normal_cur_lvl:		charger current in normal state in mA
  * @normal_vol_lvl:		charger voltage in normal state in mV
  * @maint_a_cur_lvl:		charger current in maintenance A state in mA
@@ -336,6 +340,7 @@ struct battery_type {
 	int nominal_voltage;
 	int termination_vol;
 	int termination_curr;
+	int recharge_vol;
 	int normal_cur_lvl;
 	int normal_vol_lvl;
 	int maint_a_cur_lvl;
@@ -393,6 +398,7 @@ struct ab8500_bm_charger_parameters {
  * @usb_safety_tmr_h	safety timer for usb charger
  * @bkup_bat_v		voltage which we charge the backup battery with
  * @bkup_bat_i		current which we charge the backup battery with
+ * @no_maintenance	indicates that maintenance charging is disabled
  * @adc_therm		placement of thermistor, batctrl or battemp adc
  * @chg_unknown_bat	flag to enable charging of unknown batteries
  * @enable_overshoot	flag to enable VBAT overshoot control
@@ -417,6 +423,7 @@ struct ab8500_bm_data {
 	int usb_safety_tmr_h;
 	int bkup_bat_v;
 	int bkup_bat_i;
+	bool no_maintenance;
 	bool chg_unknown_bat;
 	bool enable_overshoot;
 	enum adc_therm adc_therm;