@@ -67,16 +67,39 @@ struct axp20x_usb_power {
struct iio_channel *vbus_i;
struct delayed_work vbus_detect;
unsigned int old_status;
+ bool online;
unsigned int num_irqs;
unsigned int irqs[];
};
+static bool axp20x_usb_vbus_needs_polling(struct axp20x_usb_power *power)
+{
+ /*
+ * Polling is only necessary while VBUS is offline. While online, a
+ * present->absent transition implies an online->offline transition
+ * and will triger the VBUS_REMOVAL IRQ.
+ */
+ if (power->axp20x_id >= AXP221_ID && !power->online)
+ return true;
+
+ return false;
+}
+
static irqreturn_t axp20x_usb_power_irq(int irq, void *devid)
{
struct axp20x_usb_power *power = devid;
+ /*
+ * VBUS_PLUGIN/VBUS_REMOVAL are triggered on transitions of
+ * AXP20X_PWR_STATUS_VBUS_USED.
+ */
+ power->online = irq == power->irqs[0];
+
power_supply_changed(power->supply);
+ if (axp20x_usb_vbus_needs_polling(power))
+ mod_delayed_work(system_wq, &power->vbus_detect, DEBOUNCE_TIME);
+
return IRQ_HANDLED;
}
@@ -96,17 +119,11 @@ static void axp20x_usb_power_poll_vbus(struct work_struct *work)
power_supply_changed(power->supply);
power->old_status = val;
+ power->online = val & AXP20X_PWR_STATUS_VBUS_USED;
out:
- mod_delayed_work(system_wq, &power->vbus_detect, DEBOUNCE_TIME);
-}
-
-static bool axp20x_usb_vbus_needs_polling(struct axp20x_usb_power *power)
-{
- if (power->axp20x_id >= AXP221_ID)
- return true;
-
- return false;
+ if (axp20x_usb_vbus_needs_polling(power))
+ mod_delayed_work(system_wq, &power->vbus_detect, DEBOUNCE_TIME);
}
static int axp20x_get_current_max(struct axp20x_usb_power *power, int *val)
Investigation on the AXP803 shows that VBUS_PLUGIN/VBUS_REMOVAL IRQs are triggered on the rising/falling edge of AXP20X_PWR_STATUS_VBUS_USED. The reason IRQs do not arrive while N_VBUSEN/DRIVEVBUS is high is because AXP20X_PWR_STATUS_VBUS_USED also never goes high. This also means that if VBUS is online, a VBUS_REMOVAL IRQ is received immediately on setting N_VBUSEN/DRIVEVBUS high (and VBUS_PLUGIN shortly after it is set back low). This was also verified to be the case when manually offlining VBUS through AXP20X_VBUS_PATH_SELECT. Therefore, as long as VBUS is online, a present->absent transition necessarily implies an online->offline transition. This will cause an IRQ, and so there is no need to poll. Signed-off-by: Samuel Holland <samuel@sholland.org> --- drivers/power/supply/axp20x_usb_power.c | 35 ++++++++++++++++++------- 1 file changed, 26 insertions(+), 9 deletions(-)