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linux/drivers/power/ds2760_battery.c
Tejun Heo 41f63c5359 workqueue: use mod_delayed_work() instead of cancel + queue 
Convert delayed_work users doing cancel_delayed_work() followed by
queue_delayed_work() to mod_delayed_work().

Most conversions are straight-forward.  Ones worth mentioning are,

* drivers/edac/edac_mc.c: edac_mc_workq_setup() converted to always
  use mod_delayed_work() and cancel loop in
  edac_mc_reset_delay_period() is dropped.

* drivers/platform/x86/thinkpad_acpi.c: No need to remember whether
  watchdog is active or not.  @fan_watchdog_active and related code
  dropped.

* drivers/power/charger-manager.c: Seemingly a lot of
  delayed_work_pending() abuse going on here.
  [delayed_]work_pending() are unsynchronized and racy when used like
  this.  I converted one instance in fullbatt_handler().  Please
  conver the rest so that it invokes workqueue APIs for the intended
  target state rather than trying to game work item pending state
  transitions.  e.g. if timer should be modified - call
  mod_delayed_work(), canceled - call cancel_delayed_work[_sync]().

* drivers/thermal/thermal_sys.c: thermal_zone_device_set_polling()
  simplified.  Note that round_jiffies() calls in this function are
  meaningless.  round_jiffies() work on absolute jiffies not delta
  delay used by delayed_work.

v2: Tomi pointed out that __cancel_delayed_work() users can't be
    safely converted to mod_delayed_work().  They could be calling it
    from irq context and if that happens while delayed_work_timer_fn()
    is running, it could deadlock.  __cancel_delayed_work() users are
    dropped.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Acked-by: David Howells <dhowells@redhat.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Doug Thompson <dougthompson@xmission.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Roland Dreier <roland@kernel.org>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
2012-08-13 16:27:37 -07:00

648 lines
18 KiB
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/*
* Driver for batteries with DS2760 chips inside.
*
* Copyright © 2007 Anton Vorontsov
* 2004-2007 Matt Reimer
* 2004 Szabolcs Gyurko
*
* Use consistent with the GNU GPL is permitted,
* provided that this copyright notice is
* preserved in its entirety in all copies and derived works.
*
* Author: Anton Vorontsov <cbou@mail.ru>
* February 2007
*
* Matt Reimer <mreimer@vpop.net>
* April 2004, 2005, 2007
*
* Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
* September 2004
*/
#include <linux/module.h>
#include <linux/param.h>
#include <linux/jiffies.h>
#include <linux/workqueue.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/power_supply.h>
#include "../w1/w1.h"
#include "../w1/slaves/w1_ds2760.h"
struct ds2760_device_info {
struct device *dev;
/* DS2760 data, valid after calling ds2760_battery_read_status() */
unsigned long update_time; /* jiffies when data read */
char raw[DS2760_DATA_SIZE]; /* raw DS2760 data */
int voltage_raw; /* units of 4.88 mV */
int voltage_uV; /* units of µV */
int current_raw; /* units of 0.625 mA */
int current_uA; /* units of µA */
int accum_current_raw; /* units of 0.25 mAh */
int accum_current_uAh; /* units of µAh */
int temp_raw; /* units of 0.125 °C */
int temp_C; /* units of 0.1 °C */
int rated_capacity; /* units of µAh */
int rem_capacity; /* percentage */
int full_active_uAh; /* units of µAh */
int empty_uAh; /* units of µAh */
int life_sec; /* units of seconds */
int charge_status; /* POWER_SUPPLY_STATUS_* */
int full_counter;
struct power_supply bat;
struct device *w1_dev;
struct workqueue_struct *monitor_wqueue;
struct delayed_work monitor_work;
struct delayed_work set_charged_work;
};
static unsigned int cache_time = 1000;
module_param(cache_time, uint, 0644);
MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
static bool pmod_enabled;
module_param(pmod_enabled, bool, 0644);
MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
static unsigned int rated_capacity;
module_param(rated_capacity, uint, 0644);
MODULE_PARM_DESC(rated_capacity, "rated battery capacity, 10*mAh or index");
static unsigned int current_accum;
module_param(current_accum, uint, 0644);
MODULE_PARM_DESC(current_accum, "current accumulator value");
/* Some batteries have their rated capacity stored a N * 10 mAh, while
* others use an index into this table. */
static int rated_capacities[] = {
0,
920, /* Samsung */
920, /* BYD */
920, /* Lishen */
920, /* NEC */
1440, /* Samsung */
1440, /* BYD */
#ifdef CONFIG_MACH_H4700
1800, /* HP iPAQ hx4700 3.7V 1800mAh (359113-001) */
#else
1440, /* Lishen */
#endif
1440, /* NEC */
2880, /* Samsung */
2880, /* BYD */
2880, /* Lishen */
2880, /* NEC */
#ifdef CONFIG_MACH_H4700
0,
3600, /* HP iPAQ hx4700 3.7V 3600mAh (359114-001) */
#endif
};
/* array is level at temps 0°C, 10°C, 20°C, 30°C, 40°C
* temp is in Celsius */
static int battery_interpolate(int array[], int temp)
{
int index, dt;
if (temp <= 0)
return array[0];
if (temp >= 40)
return array[4];
index = temp / 10;
dt = temp % 10;
return array[index] + (((array[index + 1] - array[index]) * dt) / 10);
}
static int ds2760_battery_read_status(struct ds2760_device_info *di)
{
int ret, i, start, count, scale[5];
if (di->update_time && time_before(jiffies, di->update_time +
msecs_to_jiffies(cache_time)))
return 0;
/* The first time we read the entire contents of SRAM/EEPROM,
* but after that we just read the interesting bits that change. */
if (di->update_time == 0) {
start = 0;
count = DS2760_DATA_SIZE;
} else {
start = DS2760_VOLTAGE_MSB;
count = DS2760_TEMP_LSB - start + 1;
}
ret = w1_ds2760_read(di->w1_dev, di->raw + start, start, count);
if (ret != count) {
dev_warn(di->dev, "call to w1_ds2760_read failed (0x%p)\n",
di->w1_dev);
return 1;
}
di->update_time = jiffies;
/* DS2760 reports voltage in units of 4.88mV, but the battery class
* reports in units of uV, so convert by multiplying by 4880. */
di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) |
(di->raw[DS2760_VOLTAGE_LSB] >> 5);
di->voltage_uV = di->voltage_raw * 4880;
/* DS2760 reports current in signed units of 0.625mA, but the battery
* class reports in units of µA, so convert by multiplying by 625. */
di->current_raw =
(((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) |
(di->raw[DS2760_CURRENT_LSB] >> 3);
di->current_uA = di->current_raw * 625;
/* DS2760 reports accumulated current in signed units of 0.25mAh. */
di->accum_current_raw =
(((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) |
di->raw[DS2760_CURRENT_ACCUM_LSB];
di->accum_current_uAh = di->accum_current_raw * 250;
/* DS2760 reports temperature in signed units of 0.125°C, but the
* battery class reports in units of 1/10 °C, so we convert by
* multiplying by .125 * 10 = 1.25. */
di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) |
(di->raw[DS2760_TEMP_LSB] >> 5);
di->temp_C = di->temp_raw + (di->temp_raw / 4);
/* At least some battery monitors (e.g. HP iPAQ) store the battery's
* maximum rated capacity. */
if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities))
di->rated_capacity = rated_capacities[
(unsigned int)di->raw[DS2760_RATED_CAPACITY]];
else
di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10;
di->rated_capacity *= 1000; /* convert to µAh */
/* Calculate the full level at the present temperature. */
di->full_active_uAh = di->raw[DS2760_ACTIVE_FULL] << 8 |
di->raw[DS2760_ACTIVE_FULL + 1];
/* If the full_active_uAh value is not given, fall back to the rated
* capacity. This is likely to happen when chips are not part of the
* battery pack and is therefore not bootstrapped. */
if (di->full_active_uAh == 0)
di->full_active_uAh = di->rated_capacity / 1000L;
scale[0] = di->full_active_uAh;
for (i = 1; i < 5; i++)
scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 1 + i];
di->full_active_uAh = battery_interpolate(scale, di->temp_C / 10);
di->full_active_uAh *= 1000; /* convert to µAh */
/* Calculate the empty level at the present temperature. */
scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4];
for (i = 3; i >= 0; i--)
scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i];
di->empty_uAh = battery_interpolate(scale, di->temp_C / 10);
di->empty_uAh *= 1000; /* convert to µAh */
if (di->full_active_uAh == di->empty_uAh)
di->rem_capacity = 0;
else
/* From Maxim Application Note 131: remaining capacity =
* ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */
di->rem_capacity = ((di->accum_current_uAh - di->empty_uAh) * 100L) /
(di->full_active_uAh - di->empty_uAh);
if (di->rem_capacity < 0)
di->rem_capacity = 0;
if (di->rem_capacity > 100)
di->rem_capacity = 100;
if (di->current_uA < -100L)
di->life_sec = -((di->accum_current_uAh - di->empty_uAh) * 36L)
/ (di->current_uA / 100L);
else
di->life_sec = 0;
return 0;
}
static void ds2760_battery_set_current_accum(struct ds2760_device_info *di,
unsigned int acr_val)
{
unsigned char acr[2];
/* acr is in units of 0.25 mAh */
acr_val *= 4L;
acr_val /= 1000;
acr[0] = acr_val >> 8;
acr[1] = acr_val & 0xff;
if (w1_ds2760_write(di->w1_dev, acr, DS2760_CURRENT_ACCUM_MSB, 2) < 2)
dev_warn(di->dev, "ACR write failed\n");
}
static void ds2760_battery_update_status(struct ds2760_device_info *di)
{
int old_charge_status = di->charge_status;
ds2760_battery_read_status(di);
if (di->charge_status == POWER_SUPPLY_STATUS_UNKNOWN)
di->full_counter = 0;
if (power_supply_am_i_supplied(&di->bat)) {
if (di->current_uA > 10000) {
di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
di->full_counter = 0;
} else if (di->current_uA < -5000) {
if (di->charge_status != POWER_SUPPLY_STATUS_NOT_CHARGING)
dev_notice(di->dev, "not enough power to "
"charge\n");
di->charge_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
di->full_counter = 0;
} else if (di->current_uA < 10000 &&
di->charge_status != POWER_SUPPLY_STATUS_FULL) {
/* Don't consider the battery to be full unless
* we've seen the current < 10 mA at least two
* consecutive times. */
di->full_counter++;
if (di->full_counter < 2) {
di->charge_status = POWER_SUPPLY_STATUS_CHARGING;
} else {
di->charge_status = POWER_SUPPLY_STATUS_FULL;
ds2760_battery_set_current_accum(di,
di->full_active_uAh);
}
}
} else {
di->charge_status = POWER_SUPPLY_STATUS_DISCHARGING;
di->full_counter = 0;
}
if (di->charge_status != old_charge_status)
power_supply_changed(&di->bat);
}
static void ds2760_battery_write_status(struct ds2760_device_info *di,
char status)
{
if (status == di->raw[DS2760_STATUS_REG])
return;
w1_ds2760_write(di->w1_dev, &status, DS2760_STATUS_WRITE_REG, 1);
w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
}
static void ds2760_battery_write_rated_capacity(struct ds2760_device_info *di,
unsigned char rated_capacity)
{
if (rated_capacity == di->raw[DS2760_RATED_CAPACITY])
return;
w1_ds2760_write(di->w1_dev, &rated_capacity, DS2760_RATED_CAPACITY, 1);
w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
}
static void ds2760_battery_write_active_full(struct ds2760_device_info *di,
int active_full)
{
unsigned char tmp[2] = {
active_full >> 8,
active_full & 0xff
};
if (tmp[0] == di->raw[DS2760_ACTIVE_FULL] &&
tmp[1] == di->raw[DS2760_ACTIVE_FULL + 1])
return;
w1_ds2760_write(di->w1_dev, tmp, DS2760_ACTIVE_FULL, sizeof(tmp));
w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0);
w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK0);
/* Write to the di->raw[] buffer directly - the DS2760_ACTIVE_FULL
* values won't be read back by ds2760_battery_read_status() */
di->raw[DS2760_ACTIVE_FULL] = tmp[0];
di->raw[DS2760_ACTIVE_FULL + 1] = tmp[1];
}
static void ds2760_battery_work(struct work_struct *work)
{
struct ds2760_device_info *di = container_of(work,
struct ds2760_device_info, monitor_work.work);
const int interval = HZ * 60;
dev_dbg(di->dev, "%s\n", __func__);
ds2760_battery_update_status(di);
queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval);
}
#define to_ds2760_device_info(x) container_of((x), struct ds2760_device_info, \
bat);
static void ds2760_battery_external_power_changed(struct power_supply *psy)
{
struct ds2760_device_info *di = to_ds2760_device_info(psy);
dev_dbg(di->dev, "%s\n", __func__);
mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10);
}
static void ds2760_battery_set_charged_work(struct work_struct *work)
{
char bias;
struct ds2760_device_info *di = container_of(work,
struct ds2760_device_info, set_charged_work.work);
dev_dbg(di->dev, "%s\n", __func__);
ds2760_battery_read_status(di);
/* When we get notified by external circuitry that the battery is
* considered fully charged now, we know that there is no current
* flow any more. However, the ds2760's internal current meter is
* too inaccurate to rely on - spec say something ~15% failure.
* Hence, we use the current offset bias register to compensate
* that error.
*/
if (!power_supply_am_i_supplied(&di->bat))
return;
bias = (signed char) di->current_raw +
(signed char) di->raw[DS2760_CURRENT_OFFSET_BIAS];
dev_dbg(di->dev, "%s: bias = %d\n", __func__, bias);
w1_ds2760_write(di->w1_dev, &bias, DS2760_CURRENT_OFFSET_BIAS, 1);
w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
/* Write to the di->raw[] buffer directly - the CURRENT_OFFSET_BIAS
* value won't be read back by ds2760_battery_read_status() */
di->raw[DS2760_CURRENT_OFFSET_BIAS] = bias;
}
static void ds2760_battery_set_charged(struct power_supply *psy)
{
struct ds2760_device_info *di = to_ds2760_device_info(psy);
/* postpone the actual work by 20 secs. This is for debouncing GPIO
* signals and to let the current value settle. See AN4188. */
mod_delayed_work(di->monitor_wqueue, &di->set_charged_work, HZ * 20);
}
static int ds2760_battery_get_property(struct power_supply *psy,
enum power_supply_property psp,
union power_supply_propval *val)
{
struct ds2760_device_info *di = to_ds2760_device_info(psy);
switch (psp) {
case POWER_SUPPLY_PROP_STATUS:
val->intval = di->charge_status;
return 0;
default:
break;
}
ds2760_battery_read_status(di);
switch (psp) {
case POWER_SUPPLY_PROP_VOLTAGE_NOW:
val->intval = di->voltage_uV;
break;
case POWER_SUPPLY_PROP_CURRENT_NOW:
val->intval = di->current_uA;
break;
case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN:
val->intval = di->rated_capacity;
break;
case POWER_SUPPLY_PROP_CHARGE_FULL:
val->intval = di->full_active_uAh;
break;
case POWER_SUPPLY_PROP_CHARGE_EMPTY:
val->intval = di->empty_uAh;
break;
case POWER_SUPPLY_PROP_CHARGE_NOW:
val->intval = di->accum_current_uAh;
break;
case POWER_SUPPLY_PROP_TEMP:
val->intval = di->temp_C;
break;
case POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW:
val->intval = di->life_sec;
break;
case POWER_SUPPLY_PROP_CAPACITY:
val->intval = di->rem_capacity;
break;
default:
return -EINVAL;
}
return 0;
}
static int ds2760_battery_set_property(struct power_supply *psy,
enum power_supply_property psp,
const union power_supply_propval *val)
{
struct ds2760_device_info *di = to_ds2760_device_info(psy);
switch (psp) {
case POWER_SUPPLY_PROP_CHARGE_FULL:
/* the interface counts in uAh, convert the value */
ds2760_battery_write_active_full(di, val->intval / 1000L);
break;
case POWER_SUPPLY_PROP_CHARGE_NOW:
/* ds2760_battery_set_current_accum() does the conversion */
ds2760_battery_set_current_accum(di, val->intval);
break;
default:
return -EPERM;
}
return 0;
}
static int ds2760_battery_property_is_writeable(struct power_supply *psy,
enum power_supply_property psp)
{
switch (psp) {
case POWER_SUPPLY_PROP_CHARGE_FULL:
case POWER_SUPPLY_PROP_CHARGE_NOW:
return 1;
default:
break;
}
return 0;
}
static enum power_supply_property ds2760_battery_props[] = {
POWER_SUPPLY_PROP_STATUS,
POWER_SUPPLY_PROP_VOLTAGE_NOW,
POWER_SUPPLY_PROP_CURRENT_NOW,
POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN,
POWER_SUPPLY_PROP_CHARGE_FULL,
POWER_SUPPLY_PROP_CHARGE_EMPTY,
POWER_SUPPLY_PROP_CHARGE_NOW,
POWER_SUPPLY_PROP_TEMP,
POWER_SUPPLY_PROP_TIME_TO_EMPTY_NOW,
POWER_SUPPLY_PROP_CAPACITY,
};
static int ds2760_battery_probe(struct platform_device *pdev)
{
char status;
int retval = 0;
struct ds2760_device_info *di;
di = kzalloc(sizeof(*di), GFP_KERNEL);
if (!di) {
retval = -ENOMEM;
goto di_alloc_failed;
}
platform_set_drvdata(pdev, di);
di->dev = &pdev->dev;
di->w1_dev = pdev->dev.parent;
di->bat.name = dev_name(&pdev->dev);
di->bat.type = POWER_SUPPLY_TYPE_BATTERY;
di->bat.properties = ds2760_battery_props;
di->bat.num_properties = ARRAY_SIZE(ds2760_battery_props);
di->bat.get_property = ds2760_battery_get_property;
di->bat.set_property = ds2760_battery_set_property;
di->bat.property_is_writeable =
ds2760_battery_property_is_writeable;
di->bat.set_charged = ds2760_battery_set_charged;
di->bat.external_power_changed =
ds2760_battery_external_power_changed;
di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
/* enable sleep mode feature */
ds2760_battery_read_status(di);
status = di->raw[DS2760_STATUS_REG];
if (pmod_enabled)
status |= DS2760_STATUS_PMOD;
else
status &= ~DS2760_STATUS_PMOD;
ds2760_battery_write_status(di, status);
/* set rated capacity from module param */
if (rated_capacity)
ds2760_battery_write_rated_capacity(di, rated_capacity);
/* set current accumulator if given as parameter.
* this should only be done for bootstrapping the value */
if (current_accum)
ds2760_battery_set_current_accum(di, current_accum);
retval = power_supply_register(&pdev->dev, &di->bat);
if (retval) {
dev_err(di->dev, "failed to register battery\n");
goto batt_failed;
}
INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
INIT_DELAYED_WORK(&di->set_charged_work,
ds2760_battery_set_charged_work);
di->monitor_wqueue = create_singlethread_workqueue(dev_name(&pdev->dev));
if (!di->monitor_wqueue) {
retval = -ESRCH;
goto workqueue_failed;
}
queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1);
goto success;
workqueue_failed:
power_supply_unregister(&di->bat);
batt_failed:
kfree(di);
di_alloc_failed:
success:
return retval;
}
static int ds2760_battery_remove(struct platform_device *pdev)
{
struct ds2760_device_info *di = platform_get_drvdata(pdev);
cancel_delayed_work_sync(&di->monitor_work);
cancel_delayed_work_sync(&di->set_charged_work);
destroy_workqueue(di->monitor_wqueue);
power_supply_unregister(&di->bat);
kfree(di);
return 0;
}
#ifdef CONFIG_PM
static int ds2760_battery_suspend(struct platform_device *pdev,
pm_message_t state)
{
struct ds2760_device_info *di = platform_get_drvdata(pdev);
di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
return 0;
}
static int ds2760_battery_resume(struct platform_device *pdev)
{
struct ds2760_device_info *di = platform_get_drvdata(pdev);
di->charge_status = POWER_SUPPLY_STATUS_UNKNOWN;
power_supply_changed(&di->bat);
mod_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ);
return 0;
}
#else
#define ds2760_battery_suspend NULL
#define ds2760_battery_resume NULL
#endif /* CONFIG_PM */
MODULE_ALIAS("platform:ds2760-battery");
static struct platform_driver ds2760_battery_driver = {
.driver = {
.name = "ds2760-battery",
},
.probe = ds2760_battery_probe,
.remove = ds2760_battery_remove,
.suspend = ds2760_battery_suspend,
.resume = ds2760_battery_resume,
};
module_platform_driver(ds2760_battery_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
"Matt Reimer <mreimer@vpop.net>, "
"Anton Vorontsov <cbou@mail.ru>");
MODULE_DESCRIPTION("ds2760 battery driver");
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