[PATCH 09/15] power: supply: cpcap-charger: Provide state updates for battery from charger

[Tony Lindgren <tony@atomide.com>]

We want to have the battery update it's status when the charge is done,
and when the charger is disconnected. Otherwise the battery does not know
when it's full unless there's a userspace app polling the battery status.

To do this, we add supplied_to handling to cpcap-battery, and implement
power_supply_changed() for cpcap-charger. When cpcap-charger calls
power_supply_changed(), cpcap-battery will update it's status.

Let's also use new_state variable for the POWER_SUPPLY_STATUS_CHARGING
case to have unified handling for the switch.

Cc: Arthur Demchenkov <spinal.by@gmail.com>
Cc: Carl Philipp Klemm <philipp@uvos.xyz>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
---
 drivers/power/supply/cpcap-battery.c | 13 +++++++++++
 drivers/power/supply/cpcap-charger.c | 34 ++++++++++++++++++++++------
 2 files changed, 40 insertions(+), 7 deletions(-)

diff --git a/drivers/power/supply/cpcap-battery.c b/drivers/power/supply/cpcap-battery.c
--- a/drivers/power/supply/cpcap-battery.c
+++ b/drivers/power/supply/cpcap-battery.c
@@ -416,6 +416,18 @@ static int cpcap_battery_update_status(struct cpcap_battery_ddata *ddata)
 	return 0;
 }
 
+/*
+ * Update battery status when cpcap-charger calls power_supply_changed().
+ * This allows us to detect battery full condition before the charger
+ * disconnects.
+ */
+static void cpcap_battery_external_power_changed(struct power_supply *psy)
+{
+	union power_supply_propval prop;
+
+	power_supply_get_property(psy, POWER_SUPPLY_PROP_STATUS, &prop);
+}
+
 static enum power_supply_property cpcap_battery_props[] = {
 	POWER_SUPPLY_PROP_STATUS,
 	POWER_SUPPLY_PROP_PRESENT,
@@ -914,6 +926,7 @@ static int cpcap_battery_probe(struct platform_device *pdev)
 	psy_desc->get_property = cpcap_battery_get_property;
 	psy_desc->set_property = cpcap_battery_set_property;
 	psy_desc->property_is_writeable = cpcap_battery_property_is_writeable;
+	psy_desc->external_power_changed = cpcap_battery_external_power_changed;
 
 	psy_cfg.of_node = pdev->dev.of_node;
 	psy_cfg.drv_data = ddata;
diff --git a/drivers/power/supply/cpcap-charger.c b/drivers/power/supply/cpcap-charger.c
--- a/drivers/power/supply/cpcap-charger.c
+++ b/drivers/power/supply/cpcap-charger.c
@@ -613,6 +613,16 @@ static void cpcap_charger_disconnect(struct cpcap_charger_ddata *ddata,
 {
 	int error;
 
+	/* Update battery state before disconnecting the charger */
+	switch (state) {
+	case POWER_SUPPLY_STATUS_DISCHARGING:
+	case POWER_SUPPLY_STATUS_FULL:
+		power_supply_changed(ddata->usb);
+		break;
+	default:
+		break;
+	}
+
 	error = cpcap_charger_disable(ddata);
 	if (error) {
 		cpcap_charger_update_state(ddata, POWER_SUPPLY_STATUS_UNKNOWN);
@@ -628,7 +638,7 @@ static void cpcap_usb_detect(struct work_struct *work)
 {
 	struct cpcap_charger_ddata *ddata;
 	struct cpcap_charger_ints_state s;
-	int error;
+	int error, new_state;
 
 	ddata = container_of(work, struct cpcap_charger_ddata,
 			     detect_work.work);
@@ -662,19 +672,23 @@ static void cpcap_usb_detect(struct work_struct *work)
 	case POWER_SUPPLY_STATUS_CHARGING:
 		if (s.chrgcurr2)
 			break;
+		new_state = POWER_SUPPLY_STATUS_FULL;
+
 		if (s.chrgcurr1 && s.vbusvld) {
-			cpcap_charger_disconnect(ddata,
-						 POWER_SUPPLY_STATUS_FULL,
-						 HZ * 5);
+			cpcap_charger_disconnect(ddata, new_state, HZ * 5);
 			return;
 		}
 		break;
 	case POWER_SUPPLY_STATUS_FULL:
 		if (!s.chrgcurr2)
 			break;
-		cpcap_charger_disconnect(ddata,
-					 POWER_SUPPLY_STATUS_NOT_CHARGING,
-					 HZ * 5);
+		if (s.vbusvld)
+			new_state = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		else
+			new_state = POWER_SUPPLY_STATUS_DISCHARGING;
+
+		cpcap_charger_disconnect(ddata, new_state, HZ * 5);
+
 		return;
 	default:
 		break;
@@ -832,6 +846,10 @@ static int cpcap_charger_init_iio(struct cpcap_charger_ddata *ddata)
 	return error;
 }
 
+static char *cpcap_charger_supplied_to[] = {
+	"battery",
+};
+
 static const struct power_supply_desc cpcap_charger_usb_desc = {
 	.name		= "usb",
 	.type		= POWER_SUPPLY_TYPE_USB,
@@ -889,6 +907,8 @@ static int cpcap_charger_probe(struct platform_device *pdev)
 
 	psy_cfg.of_node = pdev->dev.of_node;
 	psy_cfg.drv_data = ddata;
+	psy_cfg.supplied_to = cpcap_charger_supplied_to;
+	psy_cfg.num_supplicants = ARRAY_SIZE(cpcap_charger_supplied_to),
 
 	ddata->usb = devm_power_supply_register(ddata->dev,
 						&cpcap_charger_usb_desc,
-- 
2.30.0