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authorBalaji Rao <balajirrao@openmoko.org>2009-01-27 19:23:12 +0530
committerAnton Vorontsov <cbouatmailru@gmail.com>2009-02-02 19:54:27 +0300
commit9705ecc5c1f8f34f756164a711b4cc61110c0283 (patch)
tree5fa7696dc18323c5a90af54814317d71c999b7cb /drivers/power/pcf50633-charger.c
parentccc9c8b91c2631da2cab46a6fcd9c3106dcb9abb (diff)
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>
Diffstat (limited to 'drivers/power/pcf50633-charger.c')
-rw-r--r--drivers/power/pcf50633-charger.c73
1 files changed, 71 insertions, 2 deletions
diff --git a/drivers/power/pcf50633-charger.c b/drivers/power/pcf50633-charger.c
index 41aec2acbb9..1fe1e851a8d 100644
--- a/drivers/power/pcf50633-charger.c
+++ b/drivers/power/pcf50633-charger.c
@@ -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;