[RESEND PATCH 1/3] gpio: max732x: Fix irq-events handler

[RESEND PATCH 1/3] gpio: max732x: Fix irq-events handler

[Semen Protsenko]

MAX732X clears all pending interrupts on I2C read (when interrupts
register is being read). Driver doesn't need to send any ACKs when
interrupt was handled. So replace handle_edge_irq() with
handle_simple_irq().

Using handle_edge_irq() (w/o .irq_ack callback set) may lead to NULL
pointer dereference in some cases. E.g. this was observed on
hibernation process:

  Unable to handle kernel NULL pointer dereference at virtual address 0
  Backtrace:
  (handle_edge_irq) from (resend_irqs)
  (resend_irqs) from (tasklet_action)
  (tasklet_action) from (__do_softirq)
  (__do_softirq) from (run_ksoftirqd)
  (run_ksoftirqd) from (smpboot_thread_fn)
  (smpboot_thread_fn) from (kthread)
  (kthread) from (ret_from_fork)

Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@linaro.org>
---
 drivers/gpio/gpio-max732x.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 0fa4543..7b6fb68 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -521,7 +521,7 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 		ret =  gpiochip_irqchip_add(&chip->gpio_chip,
 					    &max732x_irq_chip,
 					    irq_base,
-					    handle_edge_irq,
+					    handle_simple_irq,
 					    IRQ_TYPE_NONE);
 		if (ret) {
 			dev_err(&client->dev,
-- 
1.7.9.5

[RESEND PATCH 2/3] gpio: max732x: Add IRQF_SHARED to irq flags

[Semen Protsenko]

It's possible that multiple MAX732X can be hooked up to the same
interrupt line with the processor. So add IRQF_SHARED in requesting irq.

Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
---
 drivers/gpio/gpio-max732x.c |   10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index 7b6fb68..fafc81b 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -507,12 +507,10 @@ static int max732x_irq_setup(struct max732x_chip *chip,
 		chip->irq_features = has_irq;
 		mutex_init(&chip->irq_lock);
 
-		ret = devm_request_threaded_irq(&client->dev,
-					client->irq,
-					NULL,
-					max732x_irq_handler,
-					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
-					dev_name(&client->dev), chip);
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+				NULL, max732x_irq_handler, IRQF_ONESHOT |
+				IRQF_TRIGGER_FALLING | IRQF_SHARED,
+				dev_name(&client->dev), chip);
 		if (ret) {
 			dev_err(&client->dev, "failed to request irq %d\n",
 				client->irq);
-- 
1.7.9.5

[RESEND PATCH 3/3] gpio: max732x: Propagate wake-up setting to parent irq controller

[Semen Protsenko]

Set .irq_set_wake callback to prevent possible issues on wake-up.

This patch was inspired by this commit:
b80eef95beb04760629822fa130aeed54cdfafca

Signed-off-by: Semen Protsenko <semen.protsenko@globallogic.com>
---
 drivers/gpio/gpio-max732x.c |    9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpio/gpio-max732x.c b/drivers/gpio/gpio-max732x.c
index fafc81b..b3c497d 100644
--- a/drivers/gpio/gpio-max732x.c
+++ b/drivers/gpio/gpio-max732x.c
@@ -429,6 +429,14 @@ static int max732x_irq_set_type(struct irq_data *d, unsigned int type)
 	return 0;
 }
 
+static int max732x_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+	struct max732x_chip *chip = irq_data_get_irq_chip_data(data);
+
+	irq_set_irq_wake(chip->client->irq, on);
+	return 0;
+}
+
 static struct irq_chip max732x_irq_chip = {
 	.name			= "max732x",
 	.irq_mask		= max732x_irq_mask,
@@ -436,6 +444,7 @@ static struct irq_chip max732x_irq_chip = {
 	.irq_bus_lock		= max732x_irq_bus_lock,
 	.irq_bus_sync_unlock	= max732x_irq_bus_sync_unlock,
 	.irq_set_type		= max732x_irq_set_type,
+	.irq_set_wake           = max732x_irq_set_wake,
 };
 
 static uint8_t max732x_irq_pending(struct max732x_chip *chip)
-- 
1.7.9.5