Re: [RFC PATCH 1/2] power: Charger-Manager: add initialCharger-Manager driver
From: MyungJoo Ham
Date: Sun Nov 27 2011 - 20:20:26 EST
On Sat, Nov 26, 2011 at 10:06 AM, Anton Vorontsov
<cbouatmailru@xxxxxxxxx> wrote:
> On Thu, Nov 17, 2011 at 07:13:12PM +0900, Donggeun Kim wrote:
>> Because battery health monitoring should be done even when suspended,
>> it needs to wake up and suspend periodically. Thus, userspace battery
>> monitoring may incur too much overhead; every device and task is woken
>> up periodically. Charger Manager uses suspend-again to provide
>> in-suspend monitoring.
>>
>> This patch allows to monitor battery health in-suspend state.
>>
>> Signed-off-by: Donggeun Kim <dg77.kim@xxxxxxxxxxx>
>> Signed-off-by: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
>> Signed-off-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
>> ---
>
> I very much appreciate this effort, it discourages proprietary
> charger-managers (e.g. infamous "BME" on Nokia N900).
>
> I just Cc some people involved in embedded dev, so maybe someone
> have comments.
>
> To me the code looks technically OK (though, I'll give it a second
> review some time later).
>
> Small issue noticed though:
>
>> +#ifdef CONFIG_CHARGER_MANAGER
>> +extern int setup_charger_manager(struct charger_global_desc *gd);
>
> But the kconfig symbol is a tristate. So this won't work as a module.
> You should probably turn CHARGER_MANAGER to bool.
>
> Thanks!
Yes, it seems that we don't need to make Charger Manager as a module
as well. Thanks.
Cheers!
MyungJoo
>
>> Documentation/power/charger-manager.txt | 150 ++++++
>> drivers/power/Kconfig | 9 +
>> drivers/power/Makefile | 1 +
>> drivers/power/charger-manager.c | 771 +++++++++++++++++++++++++++++++
>> include/linux/power/charger-manager.h | 131 ++++++
>> 5 files changed, 1062 insertions(+), 0 deletions(-)
>> create mode 100644 Documentation/power/charger-manager.txt
>> create mode 100644 drivers/power/charger-manager.c
>> create mode 100644 include/linux/power/charger-manager.h
>>
>> diff --git a/Documentation/power/charger-manager.txt b/Documentation/power/charger-manager.txt
>> new file mode 100644
>> index 0000000..99630e5
>> --- /dev/null
>> +++ b/Documentation/power/charger-manager.txt
>> @@ -0,0 +1,150 @@
>> +Charger Manager
>> + (C) 2011 MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>, GPL
>> +
>> +Charger Manager provides in-kernel battery charger management that
>> +requires temperature monitoring during suspend-to-RAM state
>> +and where each battery may have multiple chargers attached and the userland
>> +wants to look at the aggregated information of the multiple chargers.
>> +
>> +Charger Manager is a platform_driver with power-supply-class entries.
>> +An instance of Charger Manager (a platform-device created with Charger-Manager)
>> +represents an independent battery with chargers. If there are multiple
>> +batteries with their own chargers acting independently in a system,
>> +the system may need multiple instances of Charger Manager.
>> +
>> +1. Introduction
>> +===============
>> +
>> +Charger Manager supports the following:
>> +
>> +* Support for multiple chargers (e.g., a device with USB, AC, and solar panels)
>> + A system may have multiple chargers (or power sources) and some of
>> + they may be activated at the same time. Each charger may have its
>> + own power-supply-class and each power-supply-class can provide
>> + different information about the battery status. This framework
>> + aggregates charger-related information from multiple sources and
>> + shows combined information as a single power-supply-class.
>> +
>> +* Support for in suspend-to-RAM polling (with suspend_again callback)
>> + While the battery is being charged and the system is in suspend-to-RAM,
>> + we may need to monitor the battery health by looking at the ambient or
>> + battery temperature. We can accomplish this by waking up the system
>> + periodically. However, such a method wakes up devices unncessary for
>> + monitoring the battery health and tasks, and user processes that are
>> + supposed to be kept suspended. That, in turn, incurs unnecessary power
>> + consumption and slow down charging process. Or even, such peak power
>> + consumption can stop chargers in the middle of charging
>> + (external power input < device power consumption), which not
>> + only affects the charging time, but the lifespan of the battery.
>> +
>> + Charger Manager provides a function "cm_suspend_again" that can be
>> + used as suspend_again callback of platform_suspend_ops. If the platform
>> + requires tasks other than cm_suspend_again, it may implement its own
>> + suspend_again callback that calls cm_suspend_again in the middle.
>> + Normally, the platform will need to resume and suspend some devices
>> + that are used by Charger Manager.
>> +
>> +2. Global Charger-Manager Data related with suspend_again
>> +========================================================
>> +In order to setup Charger Manager with suspend-again feature
>> +(in-suspend monitoring), the user should provide charger_global_desc
>> +with setup_charger_manager(struct charger_global_desc *).
>> +This charger_global_desc data for in-suspend monitoring is global
>> +as the name suggests. Thus, the user needs to provide only once even
>> +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 three entries properly in order to activate
>> +in-suspend monitoring:
>> +
>> +struct charger_global_desc {
>> +
>> +char *rtc;
>> + : The name of rtc (e.g., "rtc0") used to wakeup the system from
>> + suspend for Charger Manager. The alarm interrupt (AIE) of the rtc
>> + should be able to wake up the system from suspend. Charger Manager
>> + saves and restores the alarm value and use the previously-defined
>> + alarm if it is going to go off earlier than Charger Manager so that
>> + Charger Manager does not interfere with previously-defined alarms.
>> +
>> +bool (*is_rtc_only_wakeup_reason)(void);
>> + : This callback should let CM know whether
>> + the wakeup-from-suspend is caused only by the alarm of "rtc" in the
>> + 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.
>> +};
>> +
>> +3. How to setup suspend_again
>> +=============================
>> +Charger Manager provides a function "extern bool cm_suspend_again(void)".
>> +When cm_suspend_again is called, it monitors every battery. The suspend_ops
>> +callback of the system's platform_suspend_ops can call cm_suspend_again
>> +function to know whether Charger Manager wants to suspend again or not.
>> +If there are no other devices or tasks that want to use suspend_again
>> +feature, the platform_suspend_ops may directly refer to cm_suspend_again
>> +for its suspend_again callback.
>> +
>> +The cm_suspend_again() returns true (meaning "I want to suspend again")
>> +if the system was woken up by Charger Manager and the polling
>> +(in-suspend monitoring) results in "normal".
>> +
>> +4. Charger-Manager Data (struct charger_desc)
>> +=============================================
>> +For each battery charged independently from other batteries (if a series of
>> +batteries are charged by a single charger, they are counted as one independent
>> +battery), an instance of Charger Manager is attached to it.
>> +
>> +struct charger_desc {
>> +
>> +enum polling_modes polling_mode;
>> + : CM_POLL_DISABLE: do not poll this battery.
>> + CM_POLL_ALWAYS: always poll this battery.
>> + CM_POLL_EXTERNAL_POWER_ONLY: poll this battery if and only if
>> + an external power source is attached.
>> + CM_POLL_CHARGING_ONLY: poll this battery if and only if the
>> + battery is being charged.
>> +
>> +unsigned int polling_interval_ms;
>> + : Required polling interval in ms. Charger Manager will poll
>> + this battery every polling_interval_ms or more frequently.
>> +
>> +enum data_source battery_present;
>> + CM_FUEL_GAUGE: get battery presence information from fuel gauge.
>> + CM_CHARGER_STAT: get battery presence from chargers.
>> +
>> +char **psy_charger_stat;
>> + : An array ending with NULL that has power-supply-class names of
>> + chargers. Each power-supply-class should provide "PRESENT" (if
>> + battery_present is "CM_CHARGER_STAT"), "ONLINE" (shows whether an
>> + external power source is attached or not), and "STATUS" (shows whether
>> + the battery is {"FULL" or not FULL} or {"FULL", "Charging",
>> + "Discharging", "NotCharging"}).
>> +
>> +int num_charger_regulators;
>> +struct regulator_bulk_data *charger_regulators;
>> + : Regulators representing the chargers in the form for
>> + regulator framework's bulk functions.
>> +
>> +char *psy_fuel_gauge;
>> + : Power-supply-class name of the fuel gauge.
>> +
>> +int (*is_temperature_error)(int *mC);
>> + : This callback returns 0 if the temperature is safe for charging,
>> + a positive number if it is too hot to charge, and a negative number
>> + if it is too cold to charge. With the variable mC, the callback returns
>> + the temperature in 1/1000 of centigrade.
>> +};
>> +
>> +5. Other Considerations
>> +=======================
>> +
>> +At the charger/battery-related events such as battery-pulled-out,
>> +charger-pulled-out, charger-inserted, DCIN-over/under-voltage, charger-stopped,
>> +and others critical to chargers, the system should be configured to wake up.
>> +At least the following should wake up the system from a suspend:
>> +a) charger-on/off b) external-power-in/out c) battery-in/out (while charging)
>> +
>> +It is usually accomplished by configuring the PMIC as a wakeup source.
>> +
>> diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
>> index 9f88641..eb96b40 100644
>> --- a/drivers/power/Kconfig
>> +++ b/drivers/power/Kconfig
>> @@ -236,6 +236,15 @@ config CHARGER_GPIO
>> This driver can be build as a module. If so, the module will be
>> called gpio-charger.
>>
>> +config CHARGER_MANAGER
>> + tristate "Battery charger manager for multiple chargers"
>> + help
>> + Say Y to enable charger-manager support, which allows multiple
>> + chargers attached to a battery and multiple batteries attached to a
>> + system. The charger-manager also can monitor charging status in
>> + runtime and in suspend-to-RAM by waking up the system periodically
>> + with help of suspend_again support.
>> +
>> config CHARGER_MAX8997
>> tristate "Maxim MAX8997/MAX8966 PMIC battery charger driver"
>> depends on MFD_MAX8997 && REGULATOR_MAX8997
>> diff --git a/drivers/power/Makefile b/drivers/power/Makefile
>> index b4af13d..d3b24e9 100644
>> --- a/drivers/power/Makefile
>> +++ b/drivers/power/Makefile
>> @@ -36,5 +36,6 @@ obj-$(CONFIG_CHARGER_ISP1704) += isp1704_charger.o
>> obj-$(CONFIG_CHARGER_MAX8903) += max8903_charger.o
>> obj-$(CONFIG_CHARGER_TWL4030) += twl4030_charger.o
>> obj-$(CONFIG_CHARGER_GPIO) += gpio-charger.o
>> +obj-$(CONFIG_CHARGER_MANAGER) += charger-manager.o
>> obj-$(CONFIG_CHARGER_MAX8997) += max8997_charger.o
>> obj-$(CONFIG_CHARGER_MAX8998) += max8998_charger.o
>> diff --git a/drivers/power/charger-manager.c b/drivers/power/charger-manager.c
>> new file mode 100644
>> index 0000000..5006756
>> --- /dev/null
>> +++ b/drivers/power/charger-manager.c
>> @@ -0,0 +1,771 @@
>> +/* linux/drivers/power/charger-manager.c
>> + *
>> + * Copyright (C) 2011 Samsung Electronics Co., Ltd.
>> + * MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
>> + *
>> + * 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;
>> +static struct rtc_wkalrm rtc_wkalarm_save; /* Backup RTC alarm */
>> +static unsigned long rtc_wkalarm_save_; /* 0 if not available */
>> +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->is_temperature_error(&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 already */
>> + if (temp && cm->emergency_stop)
>> + return false;
>> +
>> + /* It has been 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 |= _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_ &&
>> + rtc_wkalarm_save_ < time) {
>> + if (rtc_wkalarm_save_ < now + CM_RTC_SMALL)
>> + time = now + CM_RTC_SMALL;
>> + else
>> + time = rtc_wkalarm_save_;
>> +
>> + /* 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)
>> + return false;
>> + if (!g_desc->is_rtc_only_wakeup_reason)
>> + return false;
>> + if (!g_desc->is_rtc_only_wakeup_reason())
>> + return false;
>> + if (!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_ &&
>> + now + CM_RTC_SMALL >= rtc_wkalarm_save_)
>> + 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->is_rtc_only_wakeup_reason) {
>> + pr_err("The callback is_wktimer_only_wkreason is not given.\n");
>> + return -EINVAL;
>> + }
>> +
>> + if (gd->rtc) {
>> + rtc_dev = rtc_class_open(gd->rtc);
>> + if (IS_ERR_OR_NULL(rtc_dev)) {
>> + rtc_dev = NULL;
>> + /* Retry at probe. RTC may be not registered yet */
>> + }
>> + } else {
>> + pr_warn("No wktimer 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;
>> +
>> + if (g_desc && !rtc_dev && g_desc->rtc) {
>> + rtc_dev = rtc_class_open(g_desc->rtc);
>> + if (IS_ERR_OR_NULL(rtc_dev)) {
>> + rtc_dev = NULL;
>> + dev_err(&pdev->dev, "Cannot get RTC %s.\n",
>> + g_desc->rtc);
>> + 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 = 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;
>> + }
>> +
>> + 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_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;
>> + }
>> +
>> + for (i = 0; desc->psy_charger_stat[i]; i++)
>> + /* Counting index only */ ;
>> +
>> + 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->is_temperature_error) {
>> + dev_err(&pdev->dev, "there is no is_temperature_error\n");
>> + ret = -EINVAL;
>> + goto err_chg_stat;
>> + }
>> +
>> + platform_set_drvdata(pdev, cm);
>> +
>> + ret = try_charger_enable(cm, true);
>> + if (ret) {
>> + dev_err(&pdev->dev, "Cannot enable charger regulators\n");
>> + goto err_chg_stat;
>> + }
>> +
>> + /* Add to the list */
>> + mutex_lock(&cm_list_mtx);
>> + list_add(&cm->entry, &cm_list);
>> + mutex_unlock(&cm_list_mtx);
>> +
>> + return 0;
>> +
>> +err_chg_stat:
>> + kfree(cm->charger_stat);
>> +err_no_charger_stat:
>> + if (desc->charger_regulators)
>> + regulator_bulk_free(desc->num_charger_regulators,
>> + desc->charger_regulators);
>> +err_no_charger:
>> + 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);
>> +
>> + kfree(cm->charger_stat);
>> + if (desc->charger_regulators)
>> + regulator_bulk_free(desc->num_charger_regulators,
>> + desc->charger_regulators);
>> + 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_);
>> + rtc_tm_to_time(&tmp, &now);
>> + if (now > rtc_wkalarm_save_)
>> + rtc_wkalarm_save_ = 0;
>> + } else {
>> + rtc_wkalarm_save_ = 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@xxxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Charger Manager");
>> +MODULE_LICENSE("GPL");
>> +MODULE_ALIAS("charger-manager");
>> diff --git a/include/linux/power/charger-manager.h b/include/linux/power/charger-manager.h
>> new file mode 100644
>> index 0000000..c91e208
>> --- /dev/null
>> +++ b/include/linux/power/charger-manager.h
>> @@ -0,0 +1,131 @@
>> +/* linux/include/linux/power/charger-manager.h
>> + *
>> + * Copyright (C) 2011 Samsung Electronics Co., Ltd.
>> + * MyungJoo.Ham <myungjoo.ham@xxxxxxxxxxx>
>> + *
>> + * Charger Manager.
>> + * This framework enables to control and multiple chargers and to
>> + * monitor charging even in the context of suspend-to-RAM with
>> + * an interface combining the chargers.
>> + *
>> + * 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.
>> +**/
>> +
>> +#ifndef _CHARGER_MANAGER_H
>> +#define _CHARGER_MANAGER_H
>> +
>> +#include <linux/power_supply.h>
>> +
>> +enum data_source {
>> + CM_FUEL_GAUGE,
>> + CM_CHARGER_STAT,
>> +};
>> +
>> +enum polling_modes {
>> + CM_POLL_DISABLE = 0,
>> + CM_POLL_ALWAYS,
>> + CM_POLL_EXTERNAL_POWER_ONLY,
>> + CM_POLL_CHARGING_ONLY,
>> +};
>> +
>> +/**
>> + * struct charger_global_desc
>> + * @rtc: the name of RTC used to wake up the system from suspend.
>> + * @is_rtc_only_wakeup_reason:
>> + * If the system is woken up by waekup-sources other than the RTC or
>> + * callbacks, Charger Manager should recognize with
>> + * is_rtc_only_wakeup_reason() returning false.
>> + * If the RTC given to CM is the only wakeup reason,
>> + * is_rtc_only_wakeup_reason should return true.
>> + */
>> +struct charger_global_desc {
>> + char *rtc;
>> +
>> + bool (*is_rtc_only_wakeup_reason)(void);
>> +};
>> +
>> +/**
>> + * struct charger_desc
>> + * @polling_mode:
>> + * Determine which polling mode will be used
>> + * @polling_interval_ms: interval in millisecond at which
>> + * charger manager will monitor battery health
>> + * @battery_present:
>> + * Specify where information for existance of battery can be obtained
>> + * @psy_charger_stat: the names of power-supply for chargers
>> + * @num_charger_regulator: the number of entries in charger_regulators
>> + * @charger_regulators: array of regulator_bulk_data for chargers
>> + * @psy_fuel_gauge: the name of power-supply for fuel gauge
>> + * @is_temperature_error:
>> + * Determine whether the status is overheat or cold or normal.
>> + * return_value > 0: overheat
>> + * return_value == 0: normal
>> + * return_value < 0: cold
>> + */
>> +struct charger_desc {
>> + enum polling_modes polling_mode;
>> + unsigned int polling_interval_ms;
>> +
>> + enum data_source battery_present;
>> +
>> + char **psy_charger_stat;
>> +
>> + int num_charger_regulators;
>> + struct regulator_bulk_data *charger_regulators;
>> +
>> + char *psy_fuel_gauge;
>> +
>> + int (*is_temperature_error)(int *mC);
>> +};
>> +
>> +#define PSY_NAME_MAX 30
>> +
>> +/**
>> + * struct charger_manager
>> + * @entry: entry for list
>> + * @dev: device pointer
>> + * @desc: instance of charger_desc
>> + * @fuel_gauge: power_supply for fuel gauge
>> + * @charger_stat: array of power_supply for chargers
>> + * @charger_enabled: the state of charger
>> + * @emergency_stop:
>> + * When setting true, stop charging
>> + * @last_temp_mC: the measured temperature in milli-Celsius
>> + * @status_save_ext_pwr_inserted:
>> + * saved status of external power before entering suspend-to-RAM
>> + * @status_save_batt:
>> + * saved status of battery before entering suspend-to-RAM
>> + */
>> +struct charger_manager {
>> + struct list_head entry;
>> + struct device *dev;
>> + struct charger_desc *desc;
>> +
>> + struct power_supply *fuel_gauge;
>> + struct power_supply **charger_stat;
>> +
>> + bool charger_enabled;
>> +
>> + int emergency_stop;
>> + int last_temp_mC;
>> +
>> + bool status_save_ext_pwr_inserted;
>> + bool status_save_batt;
>> +};
>> +
>> +#ifdef CONFIG_CHARGER_MANAGER
>> +extern int setup_charger_manager(struct charger_global_desc *gd);
>> +extern bool cm_suspend_again(void);
>> +#else
>> +static void __maybe_unused setup_charger_manager(struct charger_global_desc *gd)
>> +{ }
>> +
>> +static bool __maybe_unused cm_suspend_again(void)
>> +{
>> + return false;
>> +}
>> +#endif
>> +
>> +#endif /* _CHARGER_MANAGER_H */
>> --
>> 1.7.4.1
>
> --
> Anton Vorontsov
> Email: cbouatmailru@xxxxxxxxx
> --
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> the body of a message to majordomo@xxxxxxxxxxxxxxx
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>
--
MyungJoo Ham, Ph.D.
Mobile Software Platform Lab, DMC Business, Samsung Electronics
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