[PATCH 5.4 041/178] usb: typec: tcpci_rt1711h: avoid screaming irq causing boot hangs

[Sasha Levin]

From: Li Jun <jun.li@xxxxxxx>

commit 302c570bf36e997d55ad0d60628a2feec76954a4 upstream.

John reported screaming irq caused by rt1711h when system boot[1],
this is because irq request is done before tcpci_register_port(),
so the chip->tcpci has not been setup, irq handler is entered but
can't do anything, this patch is to address this by moving the irq
request after tcpci_register_port().

[1] https://lore.kernel.org/linux-usb/20200530040157.31038-1-john.stultz@xxxxxxxxxx

Fixes: ce08eaeb6388 ("staging: typec: rt1711h typec chip driver")
Cc: stable <stable@xxxxxxxxxxxxxxx> # v4.18+
Cc: John Stultz <john.stultz@xxxxxxxxxx>
Reported-and-tested-by: John Stultz <john.stultz@xxxxxxxxxx>
Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Li Jun <jun.li@xxxxxxx>
Link: https://lore.kernel.org/r/20200604112118.38062-1-jun.li@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/usb/typec/tcpm/tcpci_rt1711h.c | 31 +++++++++-----------------
 1 file changed, 10 insertions(+), 21 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpci_rt1711h.c b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
index 017389021b96a..b56a0880a0441 100644
--- a/drivers/usb/typec/tcpm/tcpci_rt1711h.c
+++ b/drivers/usb/typec/tcpm/tcpci_rt1711h.c
@@ -179,26 +179,6 @@ static irqreturn_t rt1711h_irq(int irq, void *dev_id)
 	return tcpci_irq(chip->tcpci);
 }
 
-static int rt1711h_init_alert(struct rt1711h_chip *chip,
-			      struct i2c_client *client)
-{
-	int ret;
-
-	/* Disable chip interrupts before requesting irq */
-	ret = rt1711h_write16(chip, TCPC_ALERT_MASK, 0);
-	if (ret < 0)
-		return ret;
-
-	ret = devm_request_threaded_irq(chip->dev, client->irq, NULL,
-					rt1711h_irq,
-					IRQF_ONESHOT | IRQF_TRIGGER_LOW,
-					dev_name(chip->dev), chip);
-	if (ret < 0)
-		return ret;
-	enable_irq_wake(client->irq);
-	return 0;
-}
-
 static int rt1711h_sw_reset(struct rt1711h_chip *chip)
 {
 	int ret;
@@ -260,7 +240,8 @@ static int rt1711h_probe(struct i2c_client *client,
 	if (ret < 0)
 		return ret;
 
-	ret = rt1711h_init_alert(chip, client);
+	/* Disable chip interrupts before requesting irq */
+	ret = rt1711h_write16(chip, TCPC_ALERT_MASK, 0);
 	if (ret < 0)
 		return ret;
 
@@ -271,6 +252,14 @@ static int rt1711h_probe(struct i2c_client *client,
 	if (IS_ERR_OR_NULL(chip->tcpci))
 		return PTR_ERR(chip->tcpci);
 
+	ret = devm_request_threaded_irq(chip->dev, client->irq, NULL,
+					rt1711h_irq,
+					IRQF_ONESHOT | IRQF_TRIGGER_LOW,
+					dev_name(chip->dev), chip);
+	if (ret < 0)
+		return ret;
+	enable_irq_wake(client->irq);
+
 	return 0;
 }
 
-- 
2.25.1