gpio: vf610: Mask all GPIO interrupts
authorAndrew Lunn <andrew@lunn.ch>
Sun, 27 Jan 2019 21:58:00 +0000 (22:58 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 13 Mar 2019 21:02:29 +0000 (14:02 -0700)
commiteda52fa18e4f8e8764cf27bf8398789a40704187
tree50a8ea842b92ea812ea28c5bee60e98ccb223c78
parent3355d641269f099906b995063fdadd6785488729
gpio: vf610: Mask all GPIO interrupts

[ Upstream commit 7ae710f9f8b2cf95297e7bbfe1c09789a7dc43d4 ]

On SoC reset all GPIO interrupts are disable. However, if kexec is
used to boot into a new kernel, the SoC does not experience a
reset. Hence GPIO interrupts can be left enabled from the previous
kernel. It is then possible for the interrupt to fire before an
interrupt handler is registered, resulting in the kernel complaining
of an "unexpected IRQ trap", the interrupt is never cleared, and so
fires again, resulting in an interrupt storm.

Disable all GPIO interrupts before registering the GPIO IRQ chip.

Fixes: 7f2691a19627 ("gpio: vf610: add gpiolib/IRQ chip driver for Vybrid")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/gpio/gpio-vf610.c