[PATCH 3.2 029/147] gpio: tegra: fix unbalanced chained_irq_enter/exit

From: Ben Hutchings
Date: Mon Nov 06 2017 - 18:41:07 EST


3.2.95-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: MichaÅ MirosÅaw <mirq-linux@xxxxxxxxxxxx>

commit 9e9509e38fbe034782339eb09c915f0b5765ff69 upstream.

When more than one GPIO IRQs are triggered simultaneously,
tegra_gpio_irq_handler() called chained_irq_exit() multiple
times for one chained_irq_enter().

Fixes: 3c92db9ac0ca3eee8e46e2424b6c074e2e394ad9
Signed-off-by: MichaÅ MirosÅaw <mirq-linux@xxxxxxxxxxxx>
[Also changed the variable to a bool]
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/gpio/gpio-tegra.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -230,7 +230,7 @@ static void tegra_gpio_irq_handler(unsig
struct tegra_gpio_bank *bank;
int port;
int pin;
- int unmasked = 0;
+ bool unmasked = false;
struct irq_chip *chip = irq_desc_get_chip(desc);

chained_irq_enter(chip, desc);
@@ -250,8 +250,8 @@ static void tegra_gpio_irq_handler(unsig
* before executing the hander so that we don't
* miss edges
*/
- if (lvl & (0x100 << pin)) {
- unmasked = 1;
+ if (!unmasked && lvl & (0x100 << pin)) {
+ unmasked = true;
chained_irq_exit(chip, desc);
}