pcf50633_charger: Enable periodic charging restart

The battery charger state machine switches into charging mode when
the battery voltage falls below 96% of a battery float voltage. But
the voltage drop in Li-ion batteries is marginal(1~2 %) till about
80% of its capacity - which means, after a BATFULL, charging won't
be restarted until 80%.

This work_struct function restarts charging at regular intervals to
make sure the battery doesn't discharge too much.

Signed-off-by: Balaji Rao <balajirrao@openmoko.org>
Cc: Andy Green <andy@openmoko.com>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
This commit is contained in:
Balaji Rao 2009-01-27 19:23:12 +05:30 committed by Anton Vorontsov
parent ccc9c8b91c
commit 9705ecc5c1
2 changed files with 73 additions and 2 deletions

View file

@ -36,6 +36,8 @@ struct pcf50633_mbc {
struct power_supply usb;
struct power_supply adapter;
struct delayed_work charging_restart_work;
};
int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
@ -43,6 +45,8 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
struct pcf50633_mbc *mbc = platform_get_drvdata(pcf->mbc_pdev);
int ret = 0;
u8 bits;
int charging_start = 1;
u8 mbcs2, chgmod;
if (ma >= 1000)
bits = PCF50633_MBCC7_USB_1000mA;
@ -50,8 +54,10 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
bits = PCF50633_MBCC7_USB_500mA;
else if (ma >= 100)
bits = PCF50633_MBCC7_USB_100mA;
else
else {
bits = PCF50633_MBCC7_USB_SUSPEND;
charging_start = 0;
}
ret = pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC7,
PCF50633_MBCC7_USB_MASK, bits);
@ -60,6 +66,22 @@ int pcf50633_mbc_usb_curlim_set(struct pcf50633 *pcf, int ma)
else
dev_info(pcf->dev, "usb curlim to %d mA\n", ma);
/* Manual charging start */
mbcs2 = pcf50633_reg_read(pcf, PCF50633_REG_MBCS2);
chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
/* If chgmod == BATFULL, setting chgena has no effect.
* We need to set resume instead.
*/
if (chgmod != PCF50633_MBCS2_MBC_BAT_FULL)
pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_CHGENA, PCF50633_MBCC1_CHGENA);
else
pcf50633_reg_set_bit_mask(pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_RESUME, PCF50633_MBCC1_RESUME);
mbc->usb_active = charging_start;
power_supply_changed(&mbc->usb);
return ret;
@ -160,10 +182,44 @@ static struct attribute_group mbc_attr_group = {
.attrs = pcf50633_mbc_sysfs_entries,
};
/* MBC state machine switches into charging mode when the battery voltage
* falls below 96% of a battery float voltage. But the voltage drop in Li-ion
* batteries is marginal(1~2 %) till about 80% of its capacity - which means,
* after a BATFULL, charging won't be restarted until 80%.
*
* This work_struct function restarts charging at regular intervals to make
* sure we don't discharge too much
*/
static void pcf50633_mbc_charging_restart(struct work_struct *work)
{
struct pcf50633_mbc *mbc;
u8 mbcs2, chgmod;
mbc = container_of(work, struct pcf50633_mbc,
charging_restart_work.work);
mbcs2 = pcf50633_reg_read(mbc->pcf, PCF50633_REG_MBCS2);
chgmod = (mbcs2 & PCF50633_MBCS2_MBC_MASK);
if (chgmod != PCF50633_MBCS2_MBC_BAT_FULL)
return;
/* Restart charging */
pcf50633_reg_set_bit_mask(mbc->pcf, PCF50633_REG_MBCC1,
PCF50633_MBCC1_RESUME, PCF50633_MBCC1_RESUME);
mbc->usb_active = 1;
power_supply_changed(&mbc->usb);
dev_info(mbc->pcf->dev, "Charging restarted\n");
}
static void
pcf50633_mbc_irq_handler(int irq, void *data)
{
struct pcf50633_mbc *mbc = data;
int chg_restart_interval =
mbc->pcf->pdata->charging_restart_interval;
/* USB */
if (irq == PCF50633_IRQ_USBINS) {
@ -172,6 +228,7 @@ pcf50633_mbc_irq_handler(int irq, void *data)
mbc->usb_online = 0;
mbc->usb_active = 0;
pcf50633_mbc_usb_curlim_set(mbc->pcf, 0);
cancel_delayed_work_sync(&mbc->charging_restart_work);
}
/* Adapter */
@ -186,7 +243,14 @@ pcf50633_mbc_irq_handler(int irq, void *data)
if (irq == PCF50633_IRQ_BATFULL) {
mbc->usb_active = 0;
mbc->adapter_active = 0;
}
if (chg_restart_interval > 0)
schedule_delayed_work(&mbc->charging_restart_work,
chg_restart_interval);
} else if (irq == PCF50633_IRQ_USBLIMON)
mbc->usb_active = 0;
else if (irq == PCF50633_IRQ_USBLIMOFF)
mbc->usb_active = 1;
power_supply_changed(&mbc->usb);
power_supply_changed(&mbc->adapter);
@ -303,6 +367,9 @@ static int __devinit pcf50633_mbc_probe(struct platform_device *pdev)
return ret;
}
INIT_DELAYED_WORK(&mbc->charging_restart_work,
pcf50633_mbc_charging_restart);
ret = sysfs_create_group(&pdev->dev.kobj, &mbc_attr_group);
if (ret)
dev_err(mbc->pcf->dev, "failed to create sysfs entries\n");
@ -328,6 +395,8 @@ static int __devexit pcf50633_mbc_remove(struct platform_device *pdev)
power_supply_unregister(&mbc->usb);
power_supply_unregister(&mbc->adapter);
cancel_delayed_work_sync(&mbc->charging_restart_work);
kfree(mbc);
return 0;

View file

@ -29,6 +29,8 @@ struct pcf50633_platform_data {
char **batteries;
int num_batteries;
int charging_restart_interval;
/* Callbacks */
void (*probe_done)(struct pcf50633 *);
void (*mbc_event_callback)(struct pcf50633 *, int);