lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <CAJ0PZbSFuJVQz3mJCJ503X0gL2Ld6DbEjLF+zeAaMcu8jag7hg@mail.gmail.com>
Date:	Mon, 28 Nov 2011 10:20:21 +0900
From:	MyungJoo Ham <myungjoo.ham@...sung.com>
To:	Anton Vorontsov <cbouatmailru@...il.com>
Cc:	Donggeun Kim <dg77.kim@...sung.com>, linux-pm@...r.kernel.org,
	len.brown@...el.com, pavel@....cz, rjw@...k.pl,
	rdunlap@...otime.net, kyungmin.park@...sung.com,
	linux-kernel@...r.kernel.org,
	Pali Rohár <pali.rohar@...il.com>,
	Philip Rakity <prakity@...vell.com>,
	Mark Brown <broonie@...nsource.wolfsonmicro.com>,
	Lars-Peter Clausen <lars@...afoo.de>
Subject: Re: [RFC PATCH 1/2] power: Charger-Manager: add initial
 Charger-Manager driver

On Sat, Nov 26, 2011 at 10:06 AM, Anton Vorontsov
<cbouatmailru@...il.com> 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@...sung.com>
>> Signed-off-by: MyungJoo Ham <myungjoo.ham@...sung.com>
>> Signed-off-by: Kyungmin Park <kyungmin.park@...sung.com>
>> ---
>
> 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@...sung.com>, 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@...sung.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;
>> +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@...sung.com>");
>> +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@...sung.com>
>> + *
>> + * 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@...il.com
> --
> To unsubscribe from this list: send the line "unsubscribe linux-pm" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>



-- 
MyungJoo Ham, Ph.D.
Mobile Software Platform Lab, DMC Business, Samsung Electronics
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ