kernel-ark/drivers/power/da9030_battery.c
Mike Rapoport a35d01a5d2 da9030_battery: Fix race between event handler and monitor
There are cases when charging monitor and the event handler try to
change the charger state simultaneously. For instance, a charger is
connected to the system, there's the detection event and the event
handler tries to enable charging. It is possible that the periodic
charging monitor runs at the same time and it still thinks there's
no external charger. So it tries to disable the charging. As the
result, even if the conditions necessary to charge the battery hold,
there will be no actual charging.

The patch changes the event handler so that instead of enabling/
disabling the charger immediately it would rather make the monitor
run. The monitor code then decides what should be the charger state.

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
2009-06-09 01:12:38 +04:00

606 lines
16 KiB
C

/*
* Battery charger driver for Dialog Semiconductor DA9030
*
* Copyright (C) 2008 Compulab, Ltd.
* Mike Rapoport <mike@compulab.co.il>
*
* 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/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/device.h>
#include <linux/workqueue.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include <linux/mfd/da903x.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#define DA9030_FAULT_LOG 0x0a
#define DA9030_FAULT_LOG_OVER_TEMP (1 << 7)
#define DA9030_FAULT_LOG_VBAT_OVER (1 << 4)
#define DA9030_CHARGE_CONTROL 0x28
#define DA9030_CHRG_CHARGER_ENABLE (1 << 7)
#define DA9030_ADC_MAN_CONTROL 0x30
#define DA9030_ADC_TBATREF_ENABLE (1 << 5)
#define DA9030_ADC_LDO_INT_ENABLE (1 << 4)
#define DA9030_ADC_AUTO_CONTROL 0x31
#define DA9030_ADC_TBAT_ENABLE (1 << 5)
#define DA9030_ADC_VBAT_IN_TXON (1 << 4)
#define DA9030_ADC_VCH_ENABLE (1 << 3)
#define DA9030_ADC_ICH_ENABLE (1 << 2)
#define DA9030_ADC_VBAT_ENABLE (1 << 1)
#define DA9030_ADC_AUTO_SLEEP_ENABLE (1 << 0)
#define DA9030_VBATMON 0x32
#define DA9030_VBATMONTXON 0x33
#define DA9030_TBATHIGHP 0x34
#define DA9030_TBATHIGHN 0x35
#define DA9030_TBATLOW 0x36
#define DA9030_VBAT_RES 0x41
#define DA9030_VBATMIN_RES 0x42
#define DA9030_VBATMINTXON_RES 0x43
#define DA9030_ICHMAX_RES 0x44
#define DA9030_ICHMIN_RES 0x45
#define DA9030_ICHAVERAGE_RES 0x46
#define DA9030_VCHMAX_RES 0x47
#define DA9030_VCHMIN_RES 0x48
#define DA9030_TBAT_RES 0x49
struct da9030_adc_res {
uint8_t vbat_res;
uint8_t vbatmin_res;
uint8_t vbatmintxon;
uint8_t ichmax_res;
uint8_t ichmin_res;
uint8_t ichaverage_res;
uint8_t vchmax_res;
uint8_t vchmin_res;
uint8_t tbat_res;
uint8_t adc_in4_res;
uint8_t adc_in5_res;
};
struct da9030_battery_thresholds {
int tbat_low;
int tbat_high;
int tbat_restart;
int vbat_low;
int vbat_crit;
int vbat_charge_start;
int vbat_charge_stop;
int vbat_charge_restart;
int vcharge_min;
int vcharge_max;
};
struct da9030_charger {
struct power_supply psy;
struct device *master;
struct da9030_adc_res adc;
struct delayed_work work;
unsigned int interval;
struct power_supply_info *battery_info;
struct da9030_battery_thresholds thresholds;
unsigned int charge_milliamp;
unsigned int charge_millivolt;
/* charger status */
bool chdet;
uint8_t fault;
int mA;
int mV;
bool is_on;
struct notifier_block nb;
/* platform callbacks for battery low and critical events */
void (*battery_low)(void);
void (*battery_critical)(void);
struct dentry *debug_file;
};
static inline int da9030_reg_to_mV(int reg)
{
return ((reg * 2650) >> 8) + 2650;
}
static inline int da9030_millivolt_to_reg(int mV)
{
return ((mV - 2650) << 8) / 2650;
}
static inline int da9030_reg_to_mA(int reg)
{
return ((reg * 24000) >> 8) / 15;
}
#ifdef CONFIG_DEBUG_FS
static int bat_debug_show(struct seq_file *s, void *data)
{
struct da9030_charger *charger = s->private;
seq_printf(s, "charger is %s\n", charger->is_on ? "on" : "off");
if (charger->chdet) {
seq_printf(s, "iset = %dmA, vset = %dmV\n",
charger->mA, charger->mV);
}
seq_printf(s, "vbat_res = %d (%dmV)\n",
charger->adc.vbat_res,
da9030_reg_to_mV(charger->adc.vbat_res));
seq_printf(s, "vbatmin_res = %d (%dmV)\n",
charger->adc.vbatmin_res,
da9030_reg_to_mV(charger->adc.vbatmin_res));
seq_printf(s, "vbatmintxon = %d (%dmV)\n",
charger->adc.vbatmintxon,
da9030_reg_to_mV(charger->adc.vbatmintxon));
seq_printf(s, "ichmax_res = %d (%dmA)\n",
charger->adc.ichmax_res,
da9030_reg_to_mV(charger->adc.ichmax_res));
seq_printf(s, "ichmin_res = %d (%dmA)\n",
charger->adc.ichmin_res,
da9030_reg_to_mA(charger->adc.ichmin_res));
seq_printf(s, "ichaverage_res = %d (%dmA)\n",
charger->adc.ichaverage_res,
da9030_reg_to_mA(charger->adc.ichaverage_res));
seq_printf(s, "vchmax_res = %d (%dmV)\n",
charger->adc.vchmax_res,
da9030_reg_to_mA(charger->adc.vchmax_res));
seq_printf(s, "vchmin_res = %d (%dmV)\n",
charger->adc.vchmin_res,
da9030_reg_to_mV(charger->adc.vchmin_res));
return 0;
}
static int debug_open(struct inode *inode, struct file *file)
{
return single_open(file, bat_debug_show, inode->i_private);
}
static const struct file_operations bat_debug_fops = {
.open = debug_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
{
charger->debug_file = debugfs_create_file("charger", 0666, 0, charger,
&bat_debug_fops);
return charger->debug_file;
}
static void da9030_bat_remove_debugfs(struct da9030_charger *charger)
{
debugfs_remove(charger->debug_file);
}
#else
static inline struct dentry *da9030_bat_create_debugfs(struct da9030_charger *charger)
{
return NULL;
}
static inline void da9030_bat_remove_debugfs(struct da9030_charger *charger)
{
}
#endif
static inline void da9030_read_adc(struct da9030_charger *charger,
struct da9030_adc_res *adc)
{
da903x_reads(charger->master, DA9030_VBAT_RES,
sizeof(*adc), (uint8_t *)adc);
}
static void da9030_charger_update_state(struct da9030_charger *charger)
{
uint8_t val;
da903x_read(charger->master, DA9030_CHARGE_CONTROL, &val);
charger->is_on = (val & DA9030_CHRG_CHARGER_ENABLE) ? 1 : 0;
charger->mA = ((val >> 3) & 0xf) * 100;
charger->mV = (val & 0x7) * 50 + 4000;
da9030_read_adc(charger, &charger->adc);
da903x_read(charger->master, DA9030_FAULT_LOG, &charger->fault);
charger->chdet = da903x_query_status(charger->master,
DA9030_STATUS_CHDET);
}
static void da9030_set_charge(struct da9030_charger *charger, int on)
{
uint8_t val;
if (on) {
val = DA9030_CHRG_CHARGER_ENABLE;
val |= (charger->charge_milliamp / 100) << 3;
val |= (charger->charge_millivolt - 4000) / 50;
charger->is_on = 1;
} else {
val = 0;
charger->is_on = 0;
}
da903x_write(charger->master, DA9030_CHARGE_CONTROL, val);
power_supply_changed(&charger->psy);
}
static void da9030_charger_check_state(struct da9030_charger *charger)
{
da9030_charger_update_state(charger);
/* we wake or boot with external power on */
if (!charger->is_on) {
if ((charger->chdet) &&
(charger->adc.vbat_res <
charger->thresholds.vbat_charge_start)) {
da9030_set_charge(charger, 1);
}
} else {
/* Charger has been pulled out */
if (!charger->chdet) {
da9030_set_charge(charger, 0);
return;
}
if (charger->adc.vbat_res >=
charger->thresholds.vbat_charge_stop) {
da9030_set_charge(charger, 0);
da903x_write(charger->master, DA9030_VBATMON,
charger->thresholds.vbat_charge_restart);
} else if (charger->adc.vbat_res >
charger->thresholds.vbat_low) {
/* we are charging and passed LOW_THRESH,
so upate DA9030 VBAT threshold
*/
da903x_write(charger->master, DA9030_VBATMON,
charger->thresholds.vbat_low);
}
if (charger->adc.vchmax_res > charger->thresholds.vcharge_max ||
charger->adc.vchmin_res < charger->thresholds.vcharge_min ||
/* Tempreture readings are negative */
charger->adc.tbat_res < charger->thresholds.tbat_high ||
charger->adc.tbat_res > charger->thresholds.tbat_low) {
/* disable charger */
da9030_set_charge(charger, 0);
}
}
}
static void da9030_charging_monitor(struct work_struct *work)
{
struct da9030_charger *charger;
charger = container_of(work, struct da9030_charger, work.work);
da9030_charger_check_state(charger);
/* reschedule for the next time */
schedule_delayed_work(&charger->work, charger->interval);
}
static enum power_supply_property da9030_battery_props[] = {
POWER_SUPPLY_PROP_MODEL_NAME,
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_HEALTH,
POWER_SUPPLY_PROP_TECHNOLOGY,
POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN,
POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_CURRENT_AVG,
};
static void da9030_battery_check_status(struct da9030_charger *charger,
union power_supply_propval *val)
{
if (charger->chdet) {
if (charger->is_on)
val->intval = POWER_SUPPLY_STATUS_CHARGING;
else
val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
} else {
val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
}
}
static void da9030_battery_check_health(struct da9030_charger *charger,
union power_supply_propval *val)
{
if (charger->fault & DA9030_FAULT_LOG_OVER_TEMP)
val->intval = POWER_SUPPLY_HEALTH_OVERHEAT;
else if (charger->fault & DA9030_FAULT_LOG_VBAT_OVER)
val->intval = POWER_SUPPLY_HEALTH_OVERVOLTAGE;
else
val->intval = POWER_SUPPLY_HEALTH_GOOD;
}
static int da9030_battery_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct da9030_charger *charger;
charger = container_of(psy, struct da9030_charger, psy);
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
da9030_battery_check_status(charger, val);
break;
case POWER_SUPPLY_PROP_HEALTH:
da9030_battery_check_health(charger, val);
break;
case POWER_SUPPLY_PROP_TECHNOLOGY:
val->intval = charger->battery_info->technology;
break;
case POWER_SUPPLY_PROP_VOLTAGE_MAX_DESIGN:
val->intval = charger->battery_info->voltage_max_design;
break;
case POWER_SUPPLY_PROP_VOLTAGE_MIN_DESIGN:
val->intval = charger->battery_info->voltage_min_design;
break;
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
val->intval = da9030_reg_to_mV(charger->adc.vbat_res) * 1000;
break;
case POWER_SUPPLY_PROP_CURRENT_AVG:
val->intval =
da9030_reg_to_mA(charger->adc.ichaverage_res) * 1000;
break;
case POWER_SUPPLY_PROP_MODEL_NAME:
val->strval = charger->battery_info->name;
break;
default:
break;
}
return 0;
}
static void da9030_battery_vbat_event(struct da9030_charger *charger)
{
da9030_read_adc(charger, &charger->adc);
if (charger->is_on)
return;
if (charger->adc.vbat_res < charger->thresholds.vbat_low) {
/* set VBAT threshold for critical */
da903x_write(charger->master, DA9030_VBATMON,
charger->thresholds.vbat_crit);
if (charger->battery_low)
charger->battery_low();
} else if (charger->adc.vbat_res <
charger->thresholds.vbat_crit) {
/* notify the system of battery critical */
if (charger->battery_critical)
charger->battery_critical();
}
}
static int da9030_battery_event(struct notifier_block *nb, unsigned long event,
void *data)
{
struct da9030_charger *charger =
container_of(nb, struct da9030_charger, nb);
switch (event) {
case DA9030_EVENT_CHDET:
cancel_delayed_work_sync(&charger->work);
schedule_work(&charger->work.work);
break;
case DA9030_EVENT_VBATMON:
da9030_battery_vbat_event(charger);
break;
case DA9030_EVENT_CHIOVER:
case DA9030_EVENT_TBAT:
da9030_set_charge(charger, 0);
break;
}
return 0;
}
static void da9030_battery_convert_thresholds(struct da9030_charger *charger,
struct da9030_battery_info *pdata)
{
charger->thresholds.tbat_low = pdata->tbat_low;
charger->thresholds.tbat_high = pdata->tbat_high;
charger->thresholds.tbat_restart = pdata->tbat_restart;
charger->thresholds.vbat_low =
da9030_millivolt_to_reg(pdata->vbat_low);
charger->thresholds.vbat_crit =
da9030_millivolt_to_reg(pdata->vbat_crit);
charger->thresholds.vbat_charge_start =
da9030_millivolt_to_reg(pdata->vbat_charge_start);
charger->thresholds.vbat_charge_stop =
da9030_millivolt_to_reg(pdata->vbat_charge_stop);
charger->thresholds.vbat_charge_restart =
da9030_millivolt_to_reg(pdata->vbat_charge_restart);
charger->thresholds.vcharge_min =
da9030_millivolt_to_reg(pdata->vcharge_min);
charger->thresholds.vcharge_max =
da9030_millivolt_to_reg(pdata->vcharge_max);
}
static void da9030_battery_setup_psy(struct da9030_charger *charger)
{
struct power_supply *psy = &charger->psy;
struct power_supply_info *info = charger->battery_info;
psy->name = info->name;
psy->use_for_apm = info->use_for_apm;
psy->type = POWER_SUPPLY_TYPE_BATTERY;
psy->get_property = da9030_battery_get_property;
psy->properties = da9030_battery_props;
psy->num_properties = ARRAY_SIZE(da9030_battery_props);
};
static int da9030_battery_charger_init(struct da9030_charger *charger)
{
char v[5];
int ret;
v[0] = v[1] = charger->thresholds.vbat_low;
v[2] = charger->thresholds.tbat_high;
v[3] = charger->thresholds.tbat_restart;
v[4] = charger->thresholds.tbat_low;
ret = da903x_writes(charger->master, DA9030_VBATMON, 5, v);
if (ret)
return ret;
/*
* Enable reference voltage supply for ADC from the LDO_INTERNAL
* regulator. Must be set before ADC measurements can be made.
*/
ret = da903x_write(charger->master, DA9030_ADC_MAN_CONTROL,
DA9030_ADC_LDO_INT_ENABLE |
DA9030_ADC_TBATREF_ENABLE);
if (ret)
return ret;
/* enable auto ADC measuremnts */
return da903x_write(charger->master, DA9030_ADC_AUTO_CONTROL,
DA9030_ADC_TBAT_ENABLE | DA9030_ADC_VBAT_IN_TXON |
DA9030_ADC_VCH_ENABLE | DA9030_ADC_ICH_ENABLE |
DA9030_ADC_VBAT_ENABLE |
DA9030_ADC_AUTO_SLEEP_ENABLE);
}
static int da9030_battery_probe(struct platform_device *pdev)
{
struct da9030_charger *charger;
struct da9030_battery_info *pdata = pdev->dev.platform_data;
int ret;
if (pdata == NULL)
return -EINVAL;
if (pdata->charge_milliamp >= 1500 ||
pdata->charge_millivolt < 4000 ||
pdata->charge_millivolt > 4350)
return -EINVAL;
charger = kzalloc(sizeof(*charger), GFP_KERNEL);
if (charger == NULL)
return -ENOMEM;
charger->master = pdev->dev.parent;
/* 10 seconds between monotor runs unless platfrom defines other
interval */
charger->interval = msecs_to_jiffies(
(pdata->batmon_interval ? : 10) * 1000);
charger->charge_milliamp = pdata->charge_milliamp;
charger->charge_millivolt = pdata->charge_millivolt;
charger->battery_info = pdata->battery_info;
charger->battery_low = pdata->battery_low;
charger->battery_critical = pdata->battery_critical;
da9030_battery_convert_thresholds(charger, pdata);
ret = da9030_battery_charger_init(charger);
if (ret)
goto err_charger_init;
INIT_DELAYED_WORK(&charger->work, da9030_charging_monitor);
schedule_delayed_work(&charger->work, charger->interval);
charger->nb.notifier_call = da9030_battery_event;
ret = da903x_register_notifier(charger->master, &charger->nb,
DA9030_EVENT_CHDET |
DA9030_EVENT_VBATMON |
DA9030_EVENT_CHIOVER |
DA9030_EVENT_TBAT);
if (ret)
goto err_notifier;
da9030_battery_setup_psy(charger);
ret = power_supply_register(&pdev->dev, &charger->psy);
if (ret)
goto err_ps_register;
charger->debug_file = da9030_bat_create_debugfs(charger);
platform_set_drvdata(pdev, charger);
return 0;
err_ps_register:
da903x_unregister_notifier(charger->master, &charger->nb,
DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
err_notifier:
cancel_delayed_work(&charger->work);
err_charger_init:
kfree(charger);
return ret;
}
static int da9030_battery_remove(struct platform_device *dev)
{
struct da9030_charger *charger = platform_get_drvdata(dev);
da9030_bat_remove_debugfs(charger);
da903x_unregister_notifier(charger->master, &charger->nb,
DA9030_EVENT_CHDET | DA9030_EVENT_VBATMON |
DA9030_EVENT_CHIOVER | DA9030_EVENT_TBAT);
cancel_delayed_work_sync(&charger->work);
da9030_set_charge(charger, 0);
power_supply_unregister(&charger->psy);
kfree(charger);
return 0;
}
static struct platform_driver da903x_battery_driver = {
.driver = {
.name = "da903x-battery",
.owner = THIS_MODULE,
},
.probe = da9030_battery_probe,
.remove = da9030_battery_remove,
};
static int da903x_battery_init(void)
{
return platform_driver_register(&da903x_battery_driver);
}
static void da903x_battery_exit(void)
{
platform_driver_unregister(&da903x_battery_driver);
}
module_init(da903x_battery_init);
module_exit(da903x_battery_exit);
MODULE_DESCRIPTION("DA9030 battery charger driver");
MODULE_AUTHOR("Mike Rapoport, CompuLab");
MODULE_LICENSE("GPL");