[PATCH] gpio/langwell: re-read the IRQ status register after each iteration

From: Mika Westerberg
Date: Thu May 10 2012 - 06:00:09 EST


Spotted by Grant Likely. The IRQ status register should be re-read after
each iteration. Otherwise the loop misses the interrupt if it gets raised
immediately after handled.

Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
---
This patch applies on top of my previous patch ("gpio: langwell: convert to
use irq_domain").

drivers/gpio/gpio-langwell.c | 4 +---
1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-langwell.c b/drivers/gpio/gpio-langwell.c
index b067357..a1c8754 100644
--- a/drivers/gpio/gpio-langwell.c
+++ b/drivers/gpio/gpio-langwell.c
@@ -250,11 +250,9 @@ static void lnw_irq_handler(unsigned irq, struct irq_desc *desc)
/* check GPIO controller to check which pin triggered the interrupt */
for (base = 0; base < lnw->chip.ngpio; base += 32) {
gedr = gpio_reg(&lnw->chip, base, GEDR);
- pending = readl(gedr);
- while (pending) {
+ while ((pending = readl(gedr))) {
gpio = __ffs(pending);
mask = BIT(gpio);
- pending &= ~mask;
/* Clear before handling so we can't lose an edge */
writel(mask, gedr);
generic_handle_irq(irq_find_mapping(lnw->domain,
--
1.7.9.1

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