[PATCH 5.9 136/152] can: m_can: m_can_open(): remove IRQF_TRIGGER_FALLING from request_threaded_irq()s flags

From: Greg Kroah-Hartman
Date: Tue Dec 01 2020 - 04:14:23 EST


From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>

[ Upstream commit 865f5b671b48d0088ce981cff1e822d9f7da441f ]

The threaded IRQ handler is used for the tcan4x5x driver only. The IRQ pin of
the tcan4x5x controller is active low, so better not use IRQF_TRIGGER_FALLING
when requesting the IRQ. As this can result in missing interrupts.

Further, if the device tree specified the interrupt as "IRQ_TYPE_LEVEL_LOW",
unloading and reloading of the driver results in the following error during
ifup:

| irq: type mismatch, failed to map hwirq-31 for gpio@20a8000!
| tcan4x5x spi1.1: m_can device registered (irq=0, version=32)
| tcan4x5x spi1.1 can2: TCAN4X5X successfully initialized.
| tcan4x5x spi1.1 can2: failed to request interrupt

This patch fixes the problem by removing the IRQF_TRIGGER_FALLING from the
request_threaded_irq().

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Cc: Dan Murphy <dmurphy@xxxxxx>
Cc: Sriram Dash <sriram.dash@xxxxxxxxxxx>
Cc: Pankaj Sharma <pankj.sharma@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201127093548.509253-1-mkl@xxxxxxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/can/m_can/m_can.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index f3fc37e96b087..c62439bdee28c 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -1653,7 +1653,7 @@ static int m_can_open(struct net_device *dev)
INIT_WORK(&cdev->tx_work, m_can_tx_work_queue);

err = request_threaded_irq(dev->irq, NULL, m_can_isr,
- IRQF_ONESHOT | IRQF_TRIGGER_FALLING,
+ IRQF_ONESHOT,
dev->name, dev);
} else {
err = request_irq(dev->irq, m_can_isr, IRQF_SHARED, dev->name,
--
2.27.0