[PATCH v3 3/6] usb: typec: tipd: Add short-circuit for no irqs

From: Sven Peter
Date: Tue Sep 28 2021 - 11:55:34 EST


If no interrupts are set in IntEventX directly skip to the end of the
interrupt handler and return IRQ_NONE instead of IRQ_HANDLED.
This possibly allows to detect spurious interrupts if the i2c bus is fast
enough.

Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Sven Peter <sven@xxxxxxxxxxxxx>
---
no changes since v2

changes since v1:
- added Heikki's r-b
- s/event/(event1 | event2)/

drivers/usb/typec/tipd/core.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tipd/core.c b/drivers/usb/typec/tipd/core.c
index 172715c6c238..e785e4aa2d4b 100644
--- a/drivers/usb/typec/tipd/core.c
+++ b/drivers/usb/typec/tipd/core.c
@@ -479,6 +479,9 @@ static irqreturn_t tps6598x_interrupt(int irq, void *data)
}
trace_tps6598x_irq(event1, event2);

+ if (!(event1 | event2))
+ goto err_unlock;
+
if (!tps6598x_read_status(tps, &status))
goto err_clear_ints;

@@ -501,7 +504,9 @@ static irqreturn_t tps6598x_interrupt(int irq, void *data)
err_unlock:
mutex_unlock(&tps->lock);

- return IRQ_HANDLED;
+ if (event1 | event2)
+ return IRQ_HANDLED;
+ return IRQ_NONE;
}

static int tps6598x_check_mode(struct tps6598x *tps)
--
2.25.1