diff mbox

[1/3] gpio: dln2: fix issue when an IRQ is unmasked then enabled

Message ID 1418302951-9309-2-git-send-email-octavian.purdila@intel.com
State Superseded
Headers show

Commit Message

Octavian Purdila Dec. 11, 2014, 1:02 p.m. UTC
As noticed during suspend/resume operations, the IRQ can be unmasked
then disabled in suspend and eventually enabled in resume, but without
being unmasked.

The current implementation does not take into account interactions
between mask/unmask and enable/disable interrupts, and thus in the
above scenarios the IRQs remain unactive.

To fix this we removed the enable/disable operations as they fallback
to mask/unmask anyway.

We also remove the pending bitmaks as it is already done in irq_data
(i.e. IRQS_PENDING).

Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
---
 drivers/gpio/gpio-dln2.c | 53 +++++++-----------------------------------------
 1 file changed, 7 insertions(+), 46 deletions(-)

Comments

Linus Walleij Dec. 31, 2014, 8:55 p.m. UTC | #1
On Thu, Dec 11, 2014 at 2:02 PM, Octavian Purdila
<octavian.purdila@intel.com> wrote:

> As noticed during suspend/resume operations, the IRQ can be unmasked
> then disabled in suspend and eventually enabled in resume, but without
> being unmasked.
>
> The current implementation does not take into account interactions
> between mask/unmask and enable/disable interrupts, and thus in the
> above scenarios the IRQs remain unactive.
>
> To fix this we removed the enable/disable operations as they fallback
> to mask/unmask anyway.
>
> We also remove the pending bitmaks as it is already done in irq_data
> (i.e. IRQS_PENDING).
>
> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>

Patch applied for fixes.

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Linus Walleij Jan. 5, 2015, 8:55 a.m. UTC | #2
On Wed, Dec 31, 2014 at 9:55 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
> On Thu, Dec 11, 2014 at 2:02 PM, Octavian Purdila
> <octavian.purdila@intel.com> wrote:
>
>> As noticed during suspend/resume operations, the IRQ can be unmasked
>> then disabled in suspend and eventually enabled in resume, but without
>> being unmasked.
>>
>> The current implementation does not take into account interactions
>> between mask/unmask and enable/disable interrupts, and thus in the
>> above scenarios the IRQs remain unactive.
>>
>> To fix this we removed the enable/disable operations as they fallback
>> to mask/unmask anyway.
>>
>> We also remove the pending bitmaks as it is already done in irq_data
>> (i.e. IRQS_PENDING).
>>
>> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
>
> Patch applied for fixes.

Bah now that I see there are several versions of the patch set
floating around and also MFD patches I don't quite understand
how acute this is or how it's to be applied.

- Are these regression fixes or nice to have for next kernel
 release?

- Are the GPIO patches independent of the MFD patch?

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Octavian Purdila Jan. 5, 2015, 10:42 a.m. UTC | #3
On Mon, Jan 5, 2015 at 6:55 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
>
> On Wed, Dec 31, 2014 at 9:55 PM, Linus Walleij <linus.walleij@linaro.org> wrote:
> > On Thu, Dec 11, 2014 at 2:02 PM, Octavian Purdila
> > <octavian.purdila@intel.com> wrote:
> >
> >> As noticed during suspend/resume operations, the IRQ can be unmasked
> >> then disabled in suspend and eventually enabled in resume, but without
> >> being unmasked.
> >>
> >> The current implementation does not take into account interactions
> >> between mask/unmask and enable/disable interrupts, and thus in the
> >> above scenarios the IRQs remain unactive.
> >>
> >> To fix this we removed the enable/disable operations as they fallback
> >> to mask/unmask anyway.
> >>
> >> We also remove the pending bitmaks as it is already done in irq_data
> >> (i.e. IRQS_PENDING).
> >>
> >> Signed-off-by: Octavian Purdila <octavian.purdila@intel.com>
> >
> > Patch applied for fixes.
>
> Bah now that I see there are several versions of the patch set
> floating around and also MFD patches I don't quite understand
> how acute this is or how it's to be applied.

Hi Linus,

Oops I did not noticed you applied the first version. It should not
matter anyway since I did not make any modifications to the GPIO
patches in the second version - I just doubled checked it now.

>
> - Are these regression fixes or nice to have for next kernel
>  release?
>

The first patch is a fix. The second is more of a cleanup patch.

> - Are the GPIO patches independent of the MFD patch?
>

Yes, the GPIO patches are independent of the MFD patches.
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
diff mbox

Patch

diff --git a/drivers/gpio/gpio-dln2.c b/drivers/gpio/gpio-dln2.c
index 978b51e..28a62c4 100644
--- a/drivers/gpio/gpio-dln2.c
+++ b/drivers/gpio/gpio-dln2.c
@@ -64,9 +64,8 @@  struct dln2_gpio {
 	 */
 	DECLARE_BITMAP(output_enabled, DLN2_GPIO_MAX_PINS);
 
-	DECLARE_BITMAP(irqs_masked, DLN2_GPIO_MAX_PINS);
-	DECLARE_BITMAP(irqs_enabled, DLN2_GPIO_MAX_PINS);
-	DECLARE_BITMAP(irqs_pending, DLN2_GPIO_MAX_PINS);
+	/* active IRQs - not synced to hardware */
+	DECLARE_BITMAP(unmasked_irqs, DLN2_GPIO_MAX_PINS);
 	struct dln2_irq_work *irq_work;
 };
 
@@ -303,29 +302,19 @@  static void dln2_irq_work(struct work_struct *w)
 	struct dln2_gpio *dln2 = iw->dln2;
 	u8 type = iw->type & DLN2_GPIO_EVENT_MASK;
 
-	if (test_bit(iw->pin, dln2->irqs_enabled))
+	if (test_bit(iw->pin, dln2->unmasked_irqs))
 		dln2_gpio_set_event_cfg(dln2, iw->pin, type, 0);
 	else
 		dln2_gpio_set_event_cfg(dln2, iw->pin, DLN2_GPIO_EVENT_NONE, 0);
 }
 
-static void dln2_irq_enable(struct irq_data *irqd)
-{
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
-	struct dln2_gpio *dln2 = container_of(gc, struct dln2_gpio, gpio);
-	int pin = irqd_to_hwirq(irqd);
-
-	set_bit(pin, dln2->irqs_enabled);
-	schedule_work(&dln2->irq_work[pin].work);
-}
-
-static void dln2_irq_disable(struct irq_data *irqd)
+static void dln2_irq_unmask(struct irq_data *irqd)
 {
 	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
 	struct dln2_gpio *dln2 = container_of(gc, struct dln2_gpio, gpio);
 	int pin = irqd_to_hwirq(irqd);
 
-	clear_bit(pin, dln2->irqs_enabled);
+	set_bit(pin, dln2->unmasked_irqs);
 	schedule_work(&dln2->irq_work[pin].work);
 }
 
@@ -335,27 +324,8 @@  static void dln2_irq_mask(struct irq_data *irqd)
 	struct dln2_gpio *dln2 = container_of(gc, struct dln2_gpio, gpio);
 	int pin = irqd_to_hwirq(irqd);
 
-	set_bit(pin, dln2->irqs_masked);
-}
-
-static void dln2_irq_unmask(struct irq_data *irqd)
-{
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
-	struct dln2_gpio *dln2 = container_of(gc, struct dln2_gpio, gpio);
-	struct device *dev = dln2->gpio.dev;
-	int pin = irqd_to_hwirq(irqd);
-
-	if (test_and_clear_bit(pin, dln2->irqs_pending)) {
-		int irq;
-
-		irq = irq_find_mapping(dln2->gpio.irqdomain, pin);
-		if (!irq) {
-			dev_err(dev, "pin %d not mapped to IRQ\n", pin);
-			return;
-		}
-
-		generic_handle_irq(irq);
-	}
+	clear_bit(pin, dln2->unmasked_irqs);
+	schedule_work(&dln2->irq_work[pin].work);
 }
 
 static int dln2_irq_set_type(struct irq_data *irqd, unsigned type)
@@ -389,8 +359,6 @@  static int dln2_irq_set_type(struct irq_data *irqd, unsigned type)
 
 static struct irq_chip dln2_gpio_irqchip = {
 	.name = "dln2-irq",
-	.irq_enable = dln2_irq_enable,
-	.irq_disable = dln2_irq_disable,
 	.irq_mask = dln2_irq_mask,
 	.irq_unmask = dln2_irq_unmask,
 	.irq_set_type = dln2_irq_set_type,
@@ -425,13 +393,6 @@  static void dln2_gpio_event(struct platform_device *pdev, u16 echo,
 		return;
 	}
 
-	if (!test_bit(pin, dln2->irqs_enabled))
-		return;
-	if (test_bit(pin, dln2->irqs_masked)) {
-		set_bit(pin, dln2->irqs_pending);
-		return;
-	}
-
 	switch (dln2->irq_work[pin].type) {
 	case DLN2_GPIO_EVENT_CHANGE_RISING:
 		if (event->value)