diff options
Diffstat (limited to 'drivers/power/charger-manager.c')
| -rw-r--r-- | drivers/power/charger-manager.c | 779 |
1 files changed, 779 insertions, 0 deletions
diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c new file mode 100644 index 00000000000..727a259ea46 --- /dev/null +++ b/drivers/power/charger-manager.c @@ -0,0 +1,779 @@ +/* + * Copyright (C) 2011 Samsung Electronics Co., Ltd. + * MyungJoo Ham <myungjoo.ham@samsung.com> + * + * This driver enables to monitor battery health and control charger + * during suspend-to-mem. + * Charger manager depends on other devices. register this later than + * the depending devices. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +**/ + +#include <linux/io.h> +#include <linux/module.h> +#include <linux/irq.h> +#include <linux/interrupt.h> +#include <linux/rtc.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/platform_device.h> +#include <linux/power/charger-manager.h> +#include <linux/regulator/consumer.h> + +/* + * Regard CM_JIFFIES_SMALL jiffies is small enough to ignore for + * delayed works so that we can run delayed works with CM_JIFFIES_SMALL + * without any delays. + */ +#define CM_JIFFIES_SMALL (2) + +/* If y is valid (> 0) and smaller than x, do x = y */ +#define CM_MIN_VALID(x, y) x = (((y > 0) && ((x) > (y))) ? (y) : (x)) + +/* + * Regard CM_RTC_SMALL (sec) is small enough to ignore error in invoking + * rtc alarm. It should be 2 or larger + */ +#define CM_RTC_SMALL (2) + +#define UEVENT_BUF_SIZE 32 + +static LIST_HEAD(cm_list); +static DEFINE_MUTEX(cm_list_mtx); + +/* About in-suspend (suspend-again) monitoring */ +static struct rtc_device *rtc_dev; +/* + * Backup RTC alarm + * Save the wakeup alarm before entering suspend-to-RAM + */ +static struct rtc_wkalrm rtc_wkalarm_save; +/* Backup RTC alarm time in terms of seconds since 01-01-1970 00:00:00 */ +static unsigned long rtc_wkalarm_save_time; +static bool cm_suspended; +static bool cm_rtc_set; +static unsigned long cm_suspend_duration_ms; + +/* Global charger-manager description */ +static struct charger_global_desc *g_desc; /* init with setup_charger_manager */ + +/** + * is_batt_present - See if the battery presents in place. + * @cm: the Charger Manager representing the battery. + */ +static bool is_batt_present(struct charger_manager *cm) +{ + union power_supply_propval val; + bool present = false; + int i, ret; + + switch (cm->desc->battery_present) { + case CM_FUEL_GAUGE: + ret = cm->fuel_gauge->get_property(cm->fuel_gauge, + POWER_SUPPLY_PROP_PRESENT, &val); + if (ret == 0 && val.intval) + present = true; + break; + case CM_CHARGER_STAT: + for (i = 0; cm->charger_stat[i]; i++) { + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_PRESENT, &val); + if (ret == 0 && val.intval) { + present = true; + break; + } + } + break; + } + + return present; +} + +/** + * is_ext_pwr_online - See if an external power source is attached to charge + * @cm: the Charger Manager representing the battery. + * + * Returns true if at least one of the chargers of the battery has an external + * power source attached to charge the battery regardless of whether it is + * actually charging or not. + */ +static bool is_ext_pwr_online(struct charger_manager *cm) +{ + union power_supply_propval val; + bool online = false; + int i, ret; + + /* If at least one of them has one, it's yes. */ + for (i = 0; cm->charger_stat[i]; i++) { + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_ONLINE, &val); + if (ret == 0 && val.intval) { + online = true; + break; + } + } + + return online; +} + +/** + * is_charging - Returns true if the battery is being charged. + * @cm: the Charger Manager representing the battery. + */ +static bool is_charging(struct charger_manager *cm) +{ + int i, ret; + bool charging = false; + union power_supply_propval val; + + /* If there is no battery, it cannot be charged */ + if (!is_batt_present(cm)) + return false; + + /* If at least one of the charger is charging, return yes */ + for (i = 0; cm->charger_stat[i]; i++) { + /* 1. The charger sholuld not be DISABLED */ + if (cm->emergency_stop) + continue; + if (!cm->charger_enabled) + continue; + + /* 2. The charger should be online (ext-power) */ + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_ONLINE, &val); + if (ret) { + dev_warn(cm->dev, "Cannot read ONLINE value from %s.\n", + cm->desc->psy_charger_stat[i]); + continue; + } + if (val.intval == 0) + continue; + + /* + * 3. The charger should not be FULL, DISCHARGING, + * or NOT_CHARGING. + */ + ret = cm->charger_stat[i]->get_property( + cm->charger_stat[i], + POWER_SUPPLY_PROP_STATUS, &val); + if (ret) { + dev_warn(cm->dev, "Cannot read STATUS value from %s.\n", + cm->desc->psy_charger_stat[i]); + continue; + } + if (val.intval == POWER_SUPPLY_STATUS_FULL || + val.intval == POWER_SUPPLY_STATUS_DISCHARGING || + val.intval == POWER_SUPPLY_STATUS_NOT_CHARGING) + continue; + + /* Then, this is charging. */ + charging = true; + break; + } + + return charging; +} + +/** + * is_polling_required - Return true if need to continue polling for this CM. + * @cm: the Charger Manager representing the battery. + */ +static bool is_polling_required(struct charger_manager *cm) +{ + switch (cm->desc->polling_mode) { + case CM_POLL_DISABLE: + return false; + case CM_POLL_ALWAYS: + return true; + case CM_POLL_EXTERNAL_POWER_ONLY: + return is_ext_pwr_online(cm); + case CM_POLL_CHARGING_ONLY: + return is_charging(cm); + default: + dev_warn(cm->dev, "Incorrect polling_mode (%d)\n", + cm->desc->polling_mode); + } + + return false; +} + +/** + * try_charger_enable - Enable/Disable chargers altogether + * @cm: the Charger Manager representing the battery. + * @enable: true: enable / false: disable + * + * Note that Charger Manager keeps the charger enabled regardless whether + * the charger is charging or not (because battery is full or no external + * power source exists) except when CM needs to disable chargers forcibly + * bacause of emergency causes; when the battery is overheated or too cold. + */ +static int try_charger_enable(struct charger_manager *cm, bool enable) +{ + int err = 0, i; + struct charger_desc *desc = cm->desc; + + /* Ignore if it's redundent command */ + if (enable && cm->charger_enabled) + return 0; + if (!enable && !cm->charger_enabled) + return 0; + + if (enable) { + if (cm->emergency_stop) + return -EAGAIN; + err = regulator_bulk_enable(desc->num_charger_regulators, + desc->charger_regulators); + } else { + /* + * Abnormal battery state - Stop charging forcibly, + * even if charger was enabled at the other places + */ + err = regulator_bulk_disable(desc->num_charger_regulators, + desc->charger_regulators); + + for (i = 0; i < desc->num_charger_regulators; i++) { + if (regulator_is_enabled( + desc->charger_regulators[i].consumer)) { + regulator_force_disable( + desc->charger_regulators[i].consumer); + dev_warn(cm->dev, + "Disable regulator(%s) forcibly.\n", + desc->charger_regulators[i].supply); + } + } + } + + if (!err) + cm->charger_enabled = enable; + + return err; +} + +/** + * uevent_notify - Let users know something has changed. + * @cm: the Charger Manager representing the battery. + * @event: the event string. + * + * If @event is null, it implies that uevent_notify is called + * by resume function. When called in the resume function, cm_suspended + * should be already reset to false in order to let uevent_notify + * notify the recent event during the suspend to users. While + * suspended, uevent_notify does not notify users, but tracks + * events so that uevent_notify can notify users later after resumed. + */ +static void uevent_notify(struct charger_manager *cm, const char *event) +{ + static char env_str[UEVENT_BUF_SIZE + 1] = ""; + static char env_str_save[UEVENT_BUF_SIZE + 1] = ""; + + if (cm_suspended) { + /* Nothing in suspended-event buffer */ + if (env_str_save[0] == 0) { + if (!strncmp(env_str, event, UEVENT_BUF_SIZE)) + return; /* status not changed */ + strncpy(env_str_save, event, UEVENT_BUF_SIZE); + return; + } + + if (!strncmp(env_str_save, event, UEVENT_BUF_SIZE)) + return; /* Duplicated. */ + else + strncpy(env_str_save, event, UEVENT_BUF_SIZE); + + return; + } + + if (event == NULL) { + /* No messages pending */ + if (!env_str_save[0]) + return; + + strncpy(env_str, env_str_save, UEVENT_BUF_SIZE); + kobject_uevent(&cm->dev->kobj, KOBJ_CHANGE); + env_str_save[0] = 0; + + return; + } + + /* status not changed */ + if (!strncmp(env_str, event, UEVENT_BUF_SIZE)) + return; + + /* save the status and notify the update */ + strncpy(env_str, event, UEVENT_BUF_SIZE); + kobject_uevent(&cm->dev->kobj, KOBJ_CHANGE); + + dev_info(cm->dev, event); +} + +/** + * _cm_monitor - Monitor the temperature and return true for exceptions. + * @cm: the Charger Manager representing the battery. + * + * Returns true if there is an event to notify for the battery. + * (True if the status of "emergency_stop" changes) + */ +static bool _cm_monitor(struct charger_manager *cm) +{ + struct charger_desc *desc = cm->desc; + int temp = desc->temperature_out_of_range(&cm->last_temp_mC); + + dev_dbg(cm->dev, "monitoring (%2.2d.%3.3dC)\n", + cm->last_temp_mC / 1000, cm->last_temp_mC % 1000); + + /* It has been stopped or charging already */ + if (!!temp == !!cm->emergency_stop) + return false; + + if (temp) { + cm->emergency_stop = temp; + if (!try_charger_enable(cm, false)) { + if (temp > 0) + uevent_notify(cm, "OVERHEAT"); + else + uevent_notify(cm, "COLD"); + } + } else { + cm->emergency_stop = 0; + if (!try_charger_enable(cm, true)) + uevent_notify(cm, "CHARGING"); + } + + return true; +} + +/** + * cm_monitor - Monitor every battery. + * + * Returns true if there is an event to notify from any of the batteries. + * (True if the status of "emergency_stop" changes) + */ +static bool cm_monitor(void) +{ + bool stop = false; + struct charger_manager *cm; + + mutex_lock(&cm_list_mtx); + + list_for_each_entry(cm, &cm_list, entry) + stop = stop || _cm_monitor(cm); + + mutex_unlock(&cm_list_mtx); + + return stop; +} + +/** + * cm_setup_timer - For in-suspend monitoring setup wakeup alarm + * for suspend_again. + * + * Returns true if the alarm is set for Charger Manager to use. + * Returns false if + * cm_setup_timer fails to set an alarm, + * cm_setup_timer does not need to set an alarm for Charger Manager, + * or an alarm previously configured is to be used. + */ +static bool cm_setup_timer(void) +{ + struct charger_manager *cm; + unsigned int wakeup_ms = UINT_MAX; + bool ret = false; + + mutex_lock(&cm_list_mtx); + + list_for_each_entry(cm, &cm_list, entry) { + /* Skip if polling is not required for this CM */ + if (!is_polling_required(cm) && !cm->emergency_stop) + continue; + if (cm->desc->polling_interval_ms == 0) + continue; + CM_MIN_VALID(wakeup_ms, cm->desc->polling_interval_ms); + } + + mutex_unlock(&cm_list_mtx); + + if (wakeup_ms < UINT_MAX && wakeup_ms > 0) { + pr_info("Charger Manager wakeup timer: %u ms.\n", wakeup_ms); + if (rtc_dev) { + struct rtc_wkalrm tmp; + unsigned long time, now; + unsigned long add = DIV_ROUND_UP(wakeup_ms, 1000); + + /* + * Set alarm with the polling interval (wakeup_ms) + * except when rtc_wkalarm_save comes first. + * However, the alarm time should be NOW + + * CM_RTC_SMALL or later. + */ + tmp.enabled = 1; + rtc_read_time(rtc_dev, &tmp.time); + rtc_tm_to_time(&tmp.time, &now); + if (add < CM_RTC_SMALL) + add = CM_RTC_SMALL; + time = now + add; + + ret = true; + + if (rtc_wkalarm_save.enabled && + rtc_wkalarm_save_time && + rtc_wkalarm_save_time < time) { + if (rtc_wkalarm_save_time < now + CM_RTC_SMALL) + time = now + CM_RTC_SMALL; + else + time = rtc_wkalarm_save_time; + + /* The timer is not appointed by CM */ + ret = false; + } + + pr_info("Waking up after %lu secs.\n", + time - now); + + rtc_time_to_tm(time, &tmp.time); + rtc_set_alarm(rtc_dev, &tmp); + cm_suspend_duration_ms += wakeup_ms; + return ret; + } + } + + if (rtc_dev) + rtc_set_alarm(rtc_dev, &rtc_wkalarm_save); + return false; +} + +/** + * cm_suspend_again - Determine whether suspend again or not + * + * Returns true if the system should be suspended again + * Returns false if the system should be woken up + */ +bool cm_suspend_again(void) +{ + struct charger_manager *cm; + bool ret = false; + + if (!g_desc || !g_desc->rtc_only_wakeup || !g_desc->rtc_only_wakeup() || + !cm_rtc_set) + return false; + + if (cm_monitor()) + goto out; + + ret = true; + mutex_lock(&cm_list_mtx); + list_for_each_entry(cm, &cm_list, entry) { + if (cm->status_save_ext_pwr_inserted != is_ext_pwr_online(cm) || + cm->status_save_batt != is_batt_present(cm)) + ret = false; + } + mutex_unlock(&cm_list_mtx); + + cm_rtc_set = cm_setup_timer(); +out: + /* It's about the time when the non-CM appointed timer goes off */ + if (rtc_wkalarm_save.enabled) { + unsigned long now; + struct rtc_time tmp; + + rtc_read_time(rtc_dev, &tmp); + rtc_tm_to_time(&tmp, &now); + + if (rtc_wkalarm_save_time && + now + CM_RTC_SMALL >= rtc_wkalarm_save_time) + return false; + } + return ret; +} +EXPORT_SYMBOL_GPL(cm_suspend_again); + +/** + * setup_charger_manager - initialize charger_global_desc data + * @gd: pointer to instance of charger_global_desc + */ +int setup_charger_manager(struct charger_global_desc *gd) +{ + if (!gd) + return -EINVAL; + + if (rtc_dev) + rtc_class_close(rtc_dev); + rtc_dev = NULL; + g_desc = NULL; + + if (!gd->rtc_only_wakeup) { + pr_err("The callback rtc_only_wakeup is not given.\n"); + return -EINVAL; + } + + if (gd->rtc_name) { + rtc_dev = rtc_class_open(gd->rtc_name); + if (IS_ERR_OR_NULL(rtc_dev)) { + rtc_dev = NULL; + /* Retry at probe. RTC may be not registered yet */ + } + } else { + pr_warn("No wakeup timer is given for charger manager." + "In-suspend monitoring won't work.\n"); + } + + g_desc = gd; + return 0; +} +EXPORT_SYMBOL_GPL(setup_charger_manager); + +static int charger_manager_probe(struct platform_device *pdev) +{ + struct charger_desc *desc = dev_get_platdata(&pdev->dev); + struct charger_manager *cm; + int ret = 0, i = 0; + + if (g_desc && !rtc_dev && g_desc->rtc_name) { + rtc_dev = rtc_class_open(g_desc->rtc_name); + if (IS_ERR_OR_NULL(rtc_dev)) { + rtc_dev = NULL; + dev_err(&pdev->dev, "Cannot get RTC %s.\n", + g_desc->rtc_name); + ret = -ENODEV; + goto err_alloc; + } + } + + if (!desc) { + dev_err(&pdev->dev, "No platform data (desc) found.\n"); + ret = -ENODEV; + goto err_alloc; + } + + cm = kzalloc(sizeof(struct charger_manager), GFP_KERNEL); + if (!cm) { + dev_err(&pdev->dev, "Cannot allocate memory.\n"); + ret = -ENOMEM; + goto err_alloc; + } + + /* Basic Values. Unspecified are Null or 0 */ + cm->dev = &pdev->dev; + cm->desc = kzalloc(sizeof(struct charger_desc), GFP_KERNEL); + if (!cm->desc) { + dev_err(&pdev->dev, "Cannot allocate memory.\n"); + ret = -ENOMEM; + goto err_alloc_desc; + } + memcpy(cm->desc, desc, sizeof(struct charger_desc)); + cm->last_temp_mC = INT_MIN; /* denotes "unmeasured, yet" */ + + if (!desc->charger_regulators || desc->num_charger_regulators < 1) { + ret = -EINVAL; + dev_err(&pdev->dev, "charger_regulators undefined.\n"); + goto err_no_charger; + } + + if (!desc->psy_charger_stat || !desc->psy_charger_stat[0]) { + dev_err(&pdev->dev, "No power supply defined.\n"); + ret = -EINVAL; + goto err_no_charger_stat; + } + + /* Counting index only */ + while (desc->psy_charger_stat[i]) + i++; + + cm->charger_stat = kzalloc(sizeof(struct power_supply *) * (i + 1), + GFP_KERNEL); + if (!cm->charger_stat) { + ret = -ENOMEM; + goto err_no_charger_stat; + } + + for (i = 0; desc->psy_charger_stat[i]; i++) { + cm->charger_stat[i] = power_supply_get_by_name( + desc->psy_charger_stat[i]); + if (!cm->charger_stat[i]) { + dev_err(&pdev->dev, "Cannot find power supply " + "\"%s\"\n", + desc->psy_charger_stat[i]); + ret = -ENODEV; + goto err_chg_stat; + } + } + + cm->fuel_gauge = power_supply_get_by_name(desc->psy_fuel_gauge); + if (!cm->fuel_gauge) { + dev_err(&pdev->dev, "Cannot find power supply \"%s\"\n", + desc->psy_fuel_gauge); + ret = -ENODEV; + goto err_chg_stat; + } + + if (desc->polling_interval_ms == 0 || + msecs_to_jiffies(desc->polling_interval_ms) <= CM_JIFFIES_SMALL) { + dev_err(&pdev->dev, "polling_interval_ms is too small\n"); + ret = -EINVAL; + goto err_chg_stat; + } + + if (!desc->temperature_out_of_range) { + dev_err(&pdev->dev, "there is no temperature_out_of_range\n"); + ret = -EINVAL; + goto err_chg_stat; + } + + platform_set_drvdata(pdev, cm); + + ret = regulator_bulk_get(&pdev->dev, desc->num_charger_regulators, + desc->charger_regulators); + if (ret) { + dev_err(&pdev->dev, "Cannot get charger regulators.\n"); + goto err_chg_stat; + } + + ret = try_charger_enable(cm, true); + if (ret) { + dev_err(&pdev->dev, "Cannot enable charger regulators\n"); + goto err_chg_enable; + } + + /* Add to the list */ + mutex_lock(&cm_list_mtx); + list_add(&cm->entry, &cm_list); + mutex_unlock(&cm_list_mtx); + + return 0; + +err_chg_enable: + if (desc->charger_regulators) + regulator_bulk_free(desc->num_charger_regulators, + desc->charger_regulators); +err_chg_stat: + kfree(cm->charger_stat); +err_no_charger_stat: +err_no_charger: + kfree(cm->desc); +err_alloc_desc: + kfree(cm); +err_alloc: + return ret; +} + +static int __devexit charger_manager_remove(struct platform_device *pdev) +{ + struct charger_manager *cm = platform_get_drvdata(pdev); + struct charger_desc *desc = cm->desc; + + /* Remove from the list */ + mutex_lock(&cm_list_mtx); + list_del(&cm->entry); + mutex_unlock(&cm_list_mtx); + + if (desc->charger_regulators) + regulator_bulk_free(desc->num_charger_regulators, + desc->charger_regulators); + kfree(cm->charger_stat); + kfree(cm->desc); + kfree(cm); + + return 0; +} + +const struct platform_device_id charger_manager_id[] = { + { "charger-manager", 0 }, + { }, +}; + +static int cm_suspend_prepare(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct charger_manager *cm = platform_get_drvdata(pdev); + + if (!cm_suspended) { + if (rtc_dev) { + struct rtc_time tmp; + unsigned long now; + + rtc_read_alarm(rtc_dev, &rtc_wkalarm_save); + rtc_read_time(rtc_dev, &tmp); + + if (rtc_wkalarm_save.enabled) { + rtc_tm_to_time(&rtc_wkalarm_save.time, + &rtc_wkalarm_save_time); + rtc_tm_to_time(&tmp, &now); + if (now > rtc_wkalarm_save_time) + rtc_wkalarm_save_time = 0; + } else { + rtc_wkalarm_save_time = 0; + } + } + cm_suspended = true; + } + + cm->status_save_ext_pwr_inserted = is_ext_pwr_online(cm); + cm->status_save_batt = is_batt_present(cm); + + if (!cm_rtc_set) { + cm_suspend_duration_ms = 0; + cm_rtc_set = cm_setup_timer(); + } + + return 0; +} + +static void cm_suspend_complete(struct device *dev) +{ + struct platform_device *pdev = container_of(dev, struct platform_device, + dev); + struct charger_manager *cm = platform_get_drvdata(pdev); + + if (cm_suspended) { + if (rtc_dev) { + struct rtc_wkalrm tmp; + + rtc_read_alarm(rtc_dev, &tmp); + rtc_wkalarm_save.pending = tmp.pending; + rtc_set_alarm(rtc_dev, &rtc_wkalarm_save); + } + cm_suspended = false; + cm_rtc_set = false; + } + + uevent_notify(cm, NULL); +} + +static const struct dev_pm_ops charger_manager_pm = { + .prepare = cm_suspend_prepare, + .complete = cm_suspend_complete, +}; + +static struct platform_driver charger_manager_driver = { + .driver = { + .name = "charger-manager", + .owner = THIS_MODULE, + .pm = &charger_manager_pm, + }, + .probe = charger_manager_probe, + .remove = __devexit_p(charger_manager_remove), + .id_table = charger_manager_id, +}; + +static int __init charger_manager_init(void) +{ + return platform_driver_register(&charger_manager_driver); +} +late_initcall(charger_manager_init); + +static void __exit charger_manager_cleanup(void) +{ + platform_driver_unregister(&charger_manager_driver); +} +module_exit(charger_manager_cleanup); + +MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); +MODULE_DESCRIPTION("Charger Manager"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("charger-manager"); |