mfd: cros_ec: Move EC interrupt to cros_ec_keyb

If we receive EC interrupts after the cros_ec driver has probed, but
before the cros_ec_keyb driver has probed, the cros_ec IRQ handler
will not run the cros_ec_keyb notifier and the EC will leave the IRQ
line asserted.  The cros_ec IRQ handler then returns IRQ_HANDLED and
the resulting flood of interrupts causes the machine to hang.

Since the EC interrupt is currently only used for the keyboard, move
the setup and handling of the EC interrupt to the cros_ec_keyb driver.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 33 insertions, 25 deletions

diff --git a/drivers/input/keyboard/cros_ec_keyb.c b/drivers/input/keyboard/cros_ec_keyb.c
index b8341ab99f55..791781ade4e7 100644
--- a/drivers/input/keyboard/cros_ec_keyb.c
+++ b/drivers/input/keyboard/cros_ec_keyb.c
@@ -24,8 +24,8 @@
 #include <linux/module.h>
 #include <linux/i2c.h>
 #include <linux/input.h>
+#include <linux/interrupt.h>
 #include <linux/kernel.h>
-#include <linux/notifier.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/input/matrix_keypad.h>
@@ -42,7 +42,6 @@
  * @dev: Device pointer
  * @idev: Input device
  * @ec: Top level ChromeOS device to use to talk to EC
- * @event_notifier: interrupt event notifier for transport devices
  */
 struct cros_ec_keyb {
 	unsigned int rows;
@@ -55,7 +54,6 @@ struct cros_ec_keyb {
 	struct device *dev;
 	struct input_dev *idev;
 	struct cros_ec_device *ec;
-	struct notifier_block notifier;
 };
 
 
@@ -173,22 +171,6 @@ static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
 	input_sync(ckdev->idev);
 }
 
-static int cros_ec_keyb_open(struct input_dev *dev)
-{
-	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
-
-	return blocking_notifier_chain_register(&ckdev->ec->event_notifier,
-						&ckdev->notifier);
-}
-
-static void cros_ec_keyb_close(struct input_dev *dev)
-{
-	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
-
-	blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
-					   &ckdev->notifier);
-}
-
 static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
 {
 	struct cros_ec_command msg = {
@@ -203,19 +185,41 @@ static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
 	return ckdev->ec->cmd_xfer(ckdev->ec, &msg);
 }
 
-static int cros_ec_keyb_work(struct notifier_block *nb,
-		     unsigned long state, void *_notify)
+static irqreturn_t cros_ec_keyb_irq(int irq, void *data)
 {
+	struct cros_ec_keyb *ckdev = data;
+	struct cros_ec_device *ec = ckdev->ec;
 	int ret;
-	struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
-						    notifier);
 	uint8_t kb_state[ckdev->cols];
 
+	if (device_may_wakeup(ec->dev))
+		pm_wakeup_event(ec->dev, 0);
+
 	ret = cros_ec_keyb_get_state(ckdev, kb_state);
 	if (ret >= 0)
 		cros_ec_keyb_process(ckdev, kb_state, ret);
+	else
+		dev_err(ec->dev, "failed to get keyboard state: %d\n", ret);
 
-	return NOTIFY_DONE;
+	return IRQ_HANDLED;
+}
+
+static int cros_ec_keyb_open(struct input_dev *dev)
+{
+	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
+	struct cros_ec_device *ec = ckdev->ec;
+
+	return request_threaded_irq(ec->irq, NULL, cros_ec_keyb_irq,
+					IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+					"cros_ec_keyb", ckdev);
+}
+
+static void cros_ec_keyb_close(struct input_dev *dev)
+{
+	struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
+	struct cros_ec_device *ec = ckdev->ec;
+
+	free_irq(ec->irq, ckdev);
 }
 
 static int cros_ec_keyb_probe(struct platform_device *pdev)
@@ -246,8 +250,12 @@ static int cros_ec_keyb_probe(struct platform_device *pdev)
 	if (!idev)
 		return -ENOMEM;
 
+	if (!ec->irq) {
+		dev_err(dev, "no EC IRQ specified\n");
+		return -EINVAL;
+	}
+
 	ckdev->ec = ec;
-	ckdev->notifier.notifier_call = cros_ec_keyb_work;
 	ckdev->dev = dev;
 	dev_set_drvdata(&pdev->dev, ckdev);