1 files changed, 55 insertions, 3 deletions

diff --git a/drivers/mfd/cros_ec.c b/drivers/mfd/cros_ec.c
index 0eee63542038..abd83424b498 100644
--- a/drivers/mfd/cros_ec.c
+++ b/drivers/mfd/cros_ec.c
@@ -23,6 +23,7 @@
 #include <linux/module.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/cros_ec.h>
+#include <asm/unaligned.h>
 
 #define CROS_EC_DEV_EC_INDEX 0
 #define CROS_EC_DEV_PD_INDEX 1
@@ -49,11 +50,28 @@ static const struct mfd_cell ec_pd_cell = {
 	.pdata_size = sizeof(pd_p),
 };
 
+static irqreturn_t ec_irq_thread(int irq, void *data)
+{
+	struct cros_ec_device *ec_dev = data;
+	int ret;
+
+	if (device_may_wakeup(ec_dev->dev))
+		pm_wakeup_event(ec_dev->dev, 0);
+
+	ret = cros_ec_get_next_event(ec_dev);
+	if (ret > 0)
+		blocking_notifier_call_chain(&ec_dev->event_notifier,
+					     0, ec_dev);
+	return IRQ_HANDLED;
+}
+
 int cros_ec_register(struct cros_ec_device *ec_dev)
 {
 	struct device *dev = ec_dev->dev;
 	int err = 0;
 
+	BLOCKING_INIT_NOTIFIER_HEAD(&ec_dev->event_notifier);
+
 	ec_dev->max_request = sizeof(struct ec_params_hello);
 	ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
 	ec_dev->max_passthru = 0;
@@ -70,13 +88,24 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 
 	cros_ec_query_all(ec_dev);
 
+	if (ec_dev->irq) {
+		err = request_threaded_irq(ec_dev->irq, NULL, ec_irq_thread,
+					   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					   "chromeos-ec", ec_dev);
+		if (err) {
+			dev_err(dev, "Failed to request IRQ %d: %d",
+				ec_dev->irq, err);
+			return err;
+		}
+	}
+
 	err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO, &ec_cell, 1,
 			      NULL, ec_dev->irq, NULL);
 	if (err) {
 		dev_err(dev,
 			"Failed to register Embedded Controller subdevice %d\n",
 			err);
-		return err;
+		goto fail_mfd;
 	}
 
 	if (ec_dev->max_passthru) {
@@ -94,7 +123,7 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 			dev_err(dev,
 				"Failed to register Power Delivery subdevice %d\n",
 				err);
-			return err;
+			goto fail_mfd;
 		}
 	}
 
@@ -103,13 +132,18 @@ int cros_ec_register(struct cros_ec_device *ec_dev)
 		if (err) {
 			mfd_remove_devices(dev);
 			dev_err(dev, "Failed to register sub-devices\n");
-			return err;
+			goto fail_mfd;
 		}
 	}
 
 	dev_info(dev, "Chrome EC device registered\n");
 
 	return 0;
+
+fail_mfd:
+	if (ec_dev->irq)
+		free_irq(ec_dev->irq, ec_dev);
+	return err;
 }
 EXPORT_SYMBOL(cros_ec_register);
 
@@ -136,13 +170,31 @@ int cros_ec_suspend(struct cros_ec_device *ec_dev)
 }
 EXPORT_SYMBOL(cros_ec_suspend);
 
+static void cros_ec_drain_events(struct cros_ec_device *ec_dev)
+{
+	while (cros_ec_get_next_event(ec_dev) > 0)
+		blocking_notifier_call_chain(&ec_dev->event_notifier,
+					     1, ec_dev);
+}
+
 int cros_ec_resume(struct cros_ec_device *ec_dev)
 {
 	enable_irq(ec_dev->irq);
 
+	/*
+	 * In some cases, we need to distinguish between events that occur
+	 * during suspend if the EC is not a wake source. For example,
+	 * keypresses during suspend should be discarded if it does not wake
+	 * the system.
+	 *
+	 * If the EC is not a wake source, drain the event queue and mark them
+	 * as "queued during suspend".
+	 */
 	if (ec_dev->wake_enabled) {
 		disable_irq_wake(ec_dev->irq);
 		ec_dev->wake_enabled = 0;
+	} else {
+		cros_ec_drain_events(ec_dev);
 	}
 
 	return 0;