From d829dc75bafb10754f35fb8895e5143d20267b04 Mon Sep 17 00:00:00 2001 From: Chanwoo Choi Date: Sat, 5 May 2012 06:24:10 -0700 Subject: charger-manager: Poll battery health in normal state Charger-Manager needs to check battery health in normal state as well as suspend-to-RAM state. When the battery is fully charged, Charger-Manager needs to determine when the chargers restart charging. This patch allows Charger-Manager to monitor battery health in normal state and handle operation for chargers after battery is fully charged. Signed-off-by: MyungJoo Ham Signed-off-by: Donggeun Kim Signed-off-by: Kyungmin Park Signed-off-by: Anton Vorontsov --- Documentation/power/charger-manager.txt | 25 +++- drivers/power/charger-manager.c | 229 ++++++++++++++++++++++++++++++++ include/linux/power/charger-manager.h | 25 ++++ 3 files changed, 278 insertions(+), 1 deletion(-) diff --git a/Documentation/power/charger-manager.txt b/Documentation/power/charger-manager.txt index fdcca991df30..9b3863386e54 100644 --- a/Documentation/power/charger-manager.txt +++ b/Documentation/power/charger-manager.txt @@ -44,6 +44,12 @@ Charger Manager supports the following: Normally, the platform will need to resume and suspend some devices that are used by Charger Manager. +* Support for premature full-battery event handling + If the battery voltage drops by "fullbatt_vchkdrop_uV" after + "fullbatt_vchkdrop_ms" from the full-battery event, the framework + restarts charging. This check is also performed while suspended by + setting wakeup time accordingly and using suspend_again. + 2. Global Charger-Manager Data related with suspend_again ======================================================== In order to setup Charger Manager with suspend-again feature @@ -55,7 +61,7 @@ if there are multiple batteries. If there are multiple batteries, the multiple instances of Charger Manager share the same charger_global_desc and it will manage in-suspend monitoring for all instances of Charger Manager. -The user needs to provide all the two entries properly in order to activate +The user needs to provide all the three entries properly in order to activate in-suspend monitoring: struct charger_global_desc { @@ -74,6 +80,11 @@ bool (*rtc_only_wakeup)(void); same struct. If there is any other wakeup source triggered the wakeup, it should return false. If the "rtc" is the only wakeup reason, it should return true. + +bool assume_timer_stops_in_suspend; + : if true, Charger Manager assumes that + the timer (CM uses jiffies as timer) stops during suspend. Then, CM + assumes that the suspend-duration is same as the alarm length. }; 3. How to setup suspend_again @@ -111,6 +122,16 @@ enum polling_modes polling_mode; CM_POLL_CHARGING_ONLY: poll this battery if and only if the battery is being charged. +unsigned int fullbatt_vchkdrop_ms; +unsigned int fullbatt_vchkdrop_uV; + : If both have non-zero values, Charger Manager will check the + battery voltage drop fullbatt_vchkdrop_ms after the battery is fully + charged. If the voltage drop is over fullbatt_vchkdrop_uV, Charger + Manager will try to recharge the battery by disabling and enabling + chargers. Recharge with voltage drop condition only (without delay + condition) is needed to be implemented with hardware interrupts from + fuel gauges or charger devices/chips. + unsigned int fullbatt_uV; : If specified with a non-zero value, Charger Manager assumes that the battery is full (capacity = 100) if the battery is not being @@ -122,6 +143,8 @@ unsigned int polling_interval_ms; this battery every polling_interval_ms or more frequently. enum data_source battery_present; + : CM_BATTERY_PRESENT: assume that the battery exists. + CM_NO_BATTERY: assume that the battery does not exists. CM_FUEL_GAUGE: get battery presence information from fuel gauge. CM_CHARGER_STAT: get battery presence from chargers. diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c index 9eca9f1ff0ea..959062d16bac 100644 --- a/drivers/power/charger-manager.c +++ b/drivers/power/charger-manager.c @@ -57,6 +57,12 @@ static bool cm_suspended; static bool cm_rtc_set; static unsigned long cm_suspend_duration_ms; +/* About normal (not suspended) monitoring */ +static unsigned long polling_jiffy = ULONG_MAX; /* ULONG_MAX: no polling */ +static unsigned long next_polling; /* Next appointed polling time */ +static struct workqueue_struct *cm_wq; /* init at driver add */ +static struct delayed_work cm_monitor_work; /* init at driver add */ + /* Global charger-manager description */ static struct charger_global_desc *g_desc; /* init with setup_charger_manager */ @@ -71,6 +77,11 @@ static bool is_batt_present(struct charger_manager *cm) int i, ret; switch (cm->desc->battery_present) { + case CM_BATTERY_PRESENT: + present = true; + break; + case CM_NO_BATTERY: + break; case CM_FUEL_GAUGE: ret = cm->fuel_gauge->get_property(cm->fuel_gauge, POWER_SUPPLY_PROP_PRESENT, &val); @@ -278,6 +289,26 @@ static int try_charger_enable(struct charger_manager *cm, bool enable) return err; } +/** + * try_charger_restart - Restart charging. + * @cm: the Charger Manager representing the battery. + * + * Restart charging by turning off and on the charger. + */ +static int try_charger_restart(struct charger_manager *cm) +{ + int err; + + if (cm->emergency_stop) + return -EAGAIN; + + err = try_charger_enable(cm, false); + if (err) + return err; + + return try_charger_enable(cm, true); +} + /** * uevent_notify - Let users know something has changed. * @cm: the Charger Manager representing the battery. @@ -333,6 +364,46 @@ static void uevent_notify(struct charger_manager *cm, const char *event) dev_info(cm->dev, event); } +/** + * fullbatt_vchk - Check voltage drop some times after "FULL" event. + * @work: the work_struct appointing the function + * + * If a user has designated "fullbatt_vchkdrop_ms/uV" values with + * charger_desc, Charger Manager checks voltage drop after the battery + * "FULL" event. It checks whether the voltage has dropped more than + * fullbatt_vchkdrop_uV by calling this function after fullbatt_vchkrop_ms. + */ +static void fullbatt_vchk(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct charger_manager *cm = container_of(dwork, + struct charger_manager, fullbatt_vchk_work); + struct charger_desc *desc = cm->desc; + int batt_uV, err, diff; + + /* remove the appointment for fullbatt_vchk */ + cm->fullbatt_vchk_jiffies_at = 0; + + if (!desc->fullbatt_vchkdrop_uV || !desc->fullbatt_vchkdrop_ms) + return; + + err = get_batt_uV(cm, &batt_uV); + if (err) { + dev_err(cm->dev, "%s: get_batt_uV error(%d).\n", __func__, err); + return; + } + + diff = cm->fullbatt_vchk_uV; + diff -= batt_uV; + + dev_dbg(cm->dev, "VBATT dropped %duV after full-batt.\n", diff); + + if (diff > desc->fullbatt_vchkdrop_uV) { + try_charger_restart(cm); + uevent_notify(cm, "Recharge"); + } +} + /** * _cm_monitor - Monitor the temperature and return true for exceptions. * @cm: the Charger Manager representing the battery. @@ -392,6 +463,68 @@ static bool cm_monitor(void) return stop; } +/** + * _setup_polling - Setup the next instance of polling. + * @work: work_struct of the function _setup_polling. + */ +static void _setup_polling(struct work_struct *work) +{ + unsigned long min = ULONG_MAX; + struct charger_manager *cm; + bool keep_polling = false; + unsigned long _next_polling; + + mutex_lock(&cm_list_mtx); + + list_for_each_entry(cm, &cm_list, entry) { + if (is_polling_required(cm) && cm->desc->polling_interval_ms) { + keep_polling = true; + + if (min > cm->desc->polling_interval_ms) + min = cm->desc->polling_interval_ms; + } + } + + polling_jiffy = msecs_to_jiffies(min); + if (polling_jiffy <= CM_JIFFIES_SMALL) + polling_jiffy = CM_JIFFIES_SMALL + 1; + + if (!keep_polling) + polling_jiffy = ULONG_MAX; + if (polling_jiffy == ULONG_MAX) + goto out; + + WARN(cm_wq == NULL, "charger-manager: workqueue not initialized" + ". try it later. %s\n", __func__); + + _next_polling = jiffies + polling_jiffy; + + if (!delayed_work_pending(&cm_monitor_work) || + (delayed_work_pending(&cm_monitor_work) && + time_after(next_polling, _next_polling))) { + cancel_delayed_work_sync(&cm_monitor_work); + next_polling = jiffies + polling_jiffy; + queue_delayed_work(cm_wq, &cm_monitor_work, polling_jiffy); + } + +out: + mutex_unlock(&cm_list_mtx); +} +static DECLARE_WORK(setup_polling, _setup_polling); + +/** + * cm_monitor_poller - The Monitor / Poller. + * @work: work_struct of the function cm_monitor_poller + * + * During non-suspended state, cm_monitor_poller is used to poll and monitor + * the batteries. + */ +static void cm_monitor_poller(struct work_struct *work) +{ + cm_monitor(); + schedule_work(&setup_polling); +} + static int charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) @@ -613,6 +746,21 @@ static bool cm_setup_timer(void) mutex_lock(&cm_list_mtx); list_for_each_entry(cm, &cm_list, entry) { + unsigned int fbchk_ms = 0; + + /* fullbatt_vchk is required. setup timer for that */ + if (cm->fullbatt_vchk_jiffies_at) { + fbchk_ms = jiffies_to_msecs(cm->fullbatt_vchk_jiffies_at + - jiffies); + if (time_is_before_eq_jiffies( + cm->fullbatt_vchk_jiffies_at) || + msecs_to_jiffies(fbchk_ms) < CM_JIFFIES_SMALL) { + fullbatt_vchk(&cm->fullbatt_vchk_work.work); + fbchk_ms = 0; + } + } + CM_MIN_VALID(wakeup_ms, fbchk_ms); + /* Skip if polling is not required for this CM */ if (!is_polling_required(cm) && !cm->emergency_stop) continue; @@ -672,6 +820,23 @@ static bool cm_setup_timer(void) return false; } +static void _cm_fbchk_in_suspend(struct charger_manager *cm) +{ + unsigned long jiffy_now = jiffies; + + if (!cm->fullbatt_vchk_jiffies_at) + return; + + if (g_desc && g_desc->assume_timer_stops_in_suspend) + jiffy_now += msecs_to_jiffies(cm_suspend_duration_ms); + + /* Execute now if it's going to be executed not too long after */ + jiffy_now += CM_JIFFIES_SMALL; + + if (time_after_eq(jiffy_now, cm->fullbatt_vchk_jiffies_at)) + fullbatt_vchk(&cm->fullbatt_vchk_work.work); +} + /** * cm_suspend_again - Determine whether suspend again or not * @@ -693,6 +858,8 @@ bool cm_suspend_again(void) ret = true; mutex_lock(&cm_list_mtx); list_for_each_entry(cm, &cm_list, entry) { + _cm_fbchk_in_suspend(cm); + if (cm->status_save_ext_pwr_inserted != is_ext_pwr_online(cm) || cm->status_save_batt != is_batt_present(cm)) { ret = false; @@ -796,6 +963,21 @@ static int charger_manager_probe(struct platform_device *pdev) memcpy(cm->desc, desc, sizeof(struct charger_desc)); cm->last_temp_mC = INT_MIN; /* denotes "unmeasured, yet" */ + /* + * The following two do not need to be errors. + * Users may intentionally ignore those two features. + */ + if (desc->fullbatt_uV == 0) { + dev_info(&pdev->dev, "Ignoring full-battery voltage threshold" + " as it is not supplied."); + } + if (!desc->fullbatt_vchkdrop_ms || !desc->fullbatt_vchkdrop_uV) { + dev_info(&pdev->dev, "Disabling full-battery voltage drop " + "checking mechanism as it is not supplied."); + desc->fullbatt_vchkdrop_ms = 0; + desc->fullbatt_vchkdrop_uV = 0; + } + if (!desc->charger_regulators || desc->num_charger_regulators < 1) { ret = -EINVAL; dev_err(&pdev->dev, "charger_regulators undefined.\n"); @@ -903,6 +1085,8 @@ static int charger_manager_probe(struct platform_device *pdev) cm->charger_psy.num_properties++; } + INIT_DELAYED_WORK(&cm->fullbatt_vchk_work, fullbatt_vchk); + ret = power_supply_register(NULL, &cm->charger_psy); if (ret) { dev_err(&pdev->dev, "Cannot register charger-manager with" @@ -928,6 +1112,8 @@ static int charger_manager_probe(struct platform_device *pdev) list_add(&cm->entry, &cm_list); mutex_unlock(&cm_list_mtx); + schedule_work(&setup_polling); + return 0; err_chg_enable: @@ -958,9 +1144,17 @@ static int __devexit charger_manager_remove(struct platform_device *pdev) list_del(&cm->entry); mutex_unlock(&cm_list_mtx); + if (work_pending(&setup_polling)) + cancel_work_sync(&setup_polling); + if (delayed_work_pending(&cm_monitor_work)) + cancel_delayed_work_sync(&cm_monitor_work); + regulator_bulk_free(desc->num_charger_regulators, desc->charger_regulators); power_supply_unregister(&cm->charger_psy); + + try_charger_enable(cm, false); + kfree(cm->charger_psy.properties); kfree(cm->charger_stat); kfree(cm->desc); @@ -1000,6 +1194,8 @@ static int cm_suspend_prepare(struct device *dev) cm_suspended = true; } + if (delayed_work_pending(&cm->fullbatt_vchk_work)) + cancel_delayed_work(&cm->fullbatt_vchk_work); cm->status_save_ext_pwr_inserted = is_ext_pwr_online(cm); cm->status_save_batt = is_batt_present(cm); @@ -1027,6 +1223,33 @@ static void cm_suspend_complete(struct device *dev) cm_rtc_set = false; } + /* Re-enqueue delayed work (fullbatt_vchk_work) */ + if (cm->fullbatt_vchk_jiffies_at) { + unsigned long delay = 0; + unsigned long now = jiffies + CM_JIFFIES_SMALL; + + if (time_after_eq(now, cm->fullbatt_vchk_jiffies_at)) { + delay = (unsigned long)((long)now + - (long)(cm->fullbatt_vchk_jiffies_at)); + delay = jiffies_to_msecs(delay); + } else { + delay = 0; + } + + /* + * Account for cm_suspend_duration_ms if + * assume_timer_stops_in_suspend is active + */ + if (g_desc && g_desc->assume_timer_stops_in_suspend) { + if (delay > cm_suspend_duration_ms) + delay -= cm_suspend_duration_ms; + else + delay = 0; + } + + queue_delayed_work(cm_wq, &cm->fullbatt_vchk_work, + msecs_to_jiffies(delay)); + } uevent_notify(cm, NULL); } @@ -1048,12 +1271,18 @@ static struct platform_driver charger_manager_driver = { static int __init charger_manager_init(void) { + cm_wq = create_freezable_workqueue("charger_manager"); + INIT_DELAYED_WORK(&cm_monitor_work, cm_monitor_poller); + return platform_driver_register(&charger_manager_driver); } late_initcall(charger_manager_init); static void __exit charger_manager_cleanup(void) { + destroy_workqueue(cm_wq); + cm_wq = NULL; + platform_driver_unregister(&charger_manager_driver); } module_exit(charger_manager_cleanup); diff --git a/include/linux/power/charger-manager.h b/include/linux/power/charger-manager.h index 4f75e531c112..baa299a95e13 100644 --- a/include/linux/power/charger-manager.h +++ b/include/linux/power/charger-manager.h @@ -18,6 +18,8 @@ #include enum data_source { + CM_BATTERY_PRESENT, + CM_NO_BATTERY, CM_FUEL_GAUGE, CM_CHARGER_STAT, }; @@ -38,11 +40,18 @@ enum polling_modes { * rtc_only_wakeup() returning false. * If the RTC given to CM is the only wakeup reason, * rtc_only_wakeup should return true. + * @assume_timer_stops_in_suspend: + * Assume that the jiffy timer stops in suspend-to-RAM. + * When enabled, CM does not rely on jiffies value in + * suspend_again and assumes that jiffies value does not + * change during suspend. */ struct charger_global_desc { char *rtc_name; bool (*rtc_only_wakeup)(void); + + bool assume_timer_stops_in_suspend; }; /** @@ -50,6 +59,11 @@ struct charger_global_desc { * @psy_name: the name of power-supply-class for charger manager * @polling_mode: * Determine which polling mode will be used + * @fullbatt_vchkdrop_ms: + * @fullbatt_vchkdrop_uV: + * Check voltage drop after the battery is fully charged. + * If it has dropped more than fullbatt_vchkdrop_uV after + * fullbatt_vchkdrop_ms, CM will restart charging. * @fullbatt_uV: voltage in microvolt * If it is not being charged and VBATT >= fullbatt_uV, * it is assumed to be full. @@ -76,6 +90,8 @@ struct charger_desc { enum polling_modes polling_mode; unsigned int polling_interval_ms; + unsigned int fullbatt_vchkdrop_ms; + unsigned int fullbatt_vchkdrop_uV; unsigned int fullbatt_uV; enum data_source battery_present; @@ -101,6 +117,11 @@ struct charger_desc { * @fuel_gauge: power_supply for fuel gauge * @charger_stat: array of power_supply for chargers * @charger_enabled: the state of charger + * @fullbatt_vchk_jiffies_at: + * jiffies at the time full battery check will occur. + * @fullbatt_vchk_uV: voltage in microvolt + * criteria for full battery + * @fullbatt_vchk_work: work queue for full battery check * @emergency_stop: * When setting true, stop charging * @last_temp_mC: the measured temperature in milli-Celsius @@ -121,6 +142,10 @@ struct charger_manager { bool charger_enabled; + unsigned long fullbatt_vchk_jiffies_at; + unsigned int fullbatt_vchk_uV; + struct delayed_work fullbatt_vchk_work; + int emergency_stop; int last_temp_mC; -- cgit