From: Christian Lamparter chunkeey@gmail.com
commit 3ab3a0689e74e6aa5b41360bc18861040ddef5b1 upstream.
When testing out gpio-keys with a button, a spurious interrupt (and therefore a key press or release event) gets triggered as soon as the driver enables the irq line for the first time.
This patch clears any potential bogus generated interrupt that was caused by the switching of the associated irq's type and polarity.
Signed-off-by: Christian Lamparter chunkeey@gmail.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Amit Pundir amit.pundir@linaro.org --- Cherry-picked from lede/openwrt tree https://git.lede-project.org/?p=source.git. To be picked up for 4.14.y as well.
arch/powerpc/platforms/4xx/uic.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/powerpc/platforms/4xx/uic.c b/arch/powerpc/platforms/4xx/uic.c index 8b4dd0da0839..9e27cfe27026 100644 --- a/arch/powerpc/platforms/4xx/uic.c +++ b/arch/powerpc/platforms/4xx/uic.c @@ -158,6 +158,7 @@ static int uic_set_irq_type(struct irq_data *d, unsigned int flow_type)
mtdcr(uic->dcrbase + UIC_PR, pr); mtdcr(uic->dcrbase + UIC_TR, tr); + mtdcr(uic->dcrbase + UIC_SR, ~mask);
raw_spin_unlock_irqrestore(&uic->lock, flags);