From 8fcfe088e21aa0db9d62eaf565757def673efba6 Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Thu, 20 Sep 2012 21:20:05 -0700 Subject: charger-manager: Support limit of maximum possible This patch check maximum possible duration of charging/discharging. If whole charging duration exceed 'desc->charging_max_duration_ms', cm stop charging to prevent overcharge/overheat. And if discharging duration exceed, charger cable is attached, after full-batt, cm start charging to maintain fully charged state for battery. Signed-off-by: Chanwoo Choi Signed-off-by: Myungjoo Ham Signed-off-by: Kyungmin Park Signed-off-by: Anton Vorontsov --- drivers/power/charger-manager.c | 80 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 79 insertions(+), 1 deletion(-) (limited to 'drivers/power/charger-manager.c') diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c index c701f5e6f327..e92ec55ced91 100644 --- a/drivers/power/charger-manager.c +++ b/drivers/power/charger-manager.c @@ -323,6 +323,14 @@ static int try_charger_enable(struct charger_manager *cm, bool enable) if (enable) { if (cm->emergency_stop) return -EAGAIN; + + /* + * Save start time of charging to limit + * maximum possible charging time. + */ + cm->charging_start_time = ktime_to_ms(ktime_get()); + cm->charging_end_time = 0; + for (i = 0 ; i < desc->num_charger_regulators ; i++) { err = regulator_enable(desc->charger_regulators[i].consumer); if (err < 0) { @@ -332,6 +340,13 @@ static int try_charger_enable(struct charger_manager *cm, bool enable) } } } else { + /* + * Save end time of charging to maintain fully charged state + * of battery after full-batt. + */ + cm->charging_start_time = 0; + cm->charging_end_time = ktime_to_ms(ktime_get()); + for (i = 0 ; i < desc->num_charger_regulators ; i++) { err = regulator_disable(desc->charger_regulators[i].consumer); if (err < 0) { @@ -474,8 +489,55 @@ static void fullbatt_vchk(struct work_struct *work) if (diff > desc->fullbatt_vchkdrop_uV) { try_charger_restart(cm); - uevent_notify(cm, "Recharge"); + uevent_notify(cm, "Recharging"); + } +} + +/** + * check_charging_duration - Monitor charging/discharging duration + * @cm: the Charger Manager representing the battery. + * + * If whole charging duration exceed 'charging_max_duration_ms', + * cm stop charging to prevent overcharge/overheat. If discharging + * duration exceed 'discharging _max_duration_ms', charger cable is + * attached, after full-batt, cm start charging to maintain fully + * charged state for battery. + */ +static int check_charging_duration(struct charger_manager *cm) +{ + struct charger_desc *desc = cm->desc; + u64 curr = ktime_to_ms(ktime_get()); + u64 duration; + int ret = false; + + if (!desc->charging_max_duration_ms && + !desc->discharging_max_duration_ms) + return ret; + + if (cm->charger_enabled) { + duration = curr - cm->charging_start_time; + + if (duration > desc->charging_max_duration_ms) { + dev_info(cm->dev, "Charging duration exceed %lldms", + desc->charging_max_duration_ms); + uevent_notify(cm, "Discharging"); + try_charger_enable(cm, false); + ret = true; + } + } else if (is_ext_pwr_online(cm) && !cm->charger_enabled) { + duration = curr - cm->charging_end_time; + + if (duration > desc->charging_max_duration_ms && + is_ext_pwr_online(cm)) { + dev_info(cm->dev, "DisCharging duration exceed %lldms", + desc->discharging_max_duration_ms); + uevent_notify(cm, "Recharing"); + try_charger_enable(cm, true); + ret = true; + } } + + return ret; } /** @@ -510,6 +572,13 @@ static bool _cm_monitor(struct charger_manager *cm) uevent_notify(cm, "COLD"); } + /* + * Check whole charging duration and discharing duration + * after full-batt. + */ + } else if (!cm->emergency_stop && check_charging_duration(cm)) { + dev_dbg(cm->dev, + "Charging/Discharging duration is out of range"); /* * Check dropped voltage of battery. If battery voltage is more * dropped than fullbatt_vchkdrop_uV after fully charged state, @@ -1271,6 +1340,15 @@ static int charger_manager_probe(struct platform_device *pdev) goto err_chg_stat; } + if (!desc->charging_max_duration_ms || + !desc->discharging_max_duration_ms) { + dev_info(&pdev->dev, "Cannot limit charging duration " + "checking mechanism to prevent overcharge/overheat " + "and control discharging duration"); + desc->charging_max_duration_ms = 0; + desc->discharging_max_duration_ms = 0; + } + platform_set_drvdata(pdev, cm); memcpy(&cm->charger_psy, &psy_default, sizeof(psy_default)); -- cgit v1.2.3