[PATCH 1/2] gpio: tegra: create irq mapping in gpio_to_irq

[PATCH 1/2] gpio: tegra: create irq mapping in gpio_to_irq

[Laxman Dewangan]

The gpio interrupts get mapped linearly and hence the mapping
of irq need to be created by irq_create_mapping().

The function gpio_to_irq() returns the irq by irq_find_mapping()
and so returns 0 as there is no mapping created. Fix the function
to create mapping when gpio_to_irq() get called.

Signed-off-by: Laxman Dewangan <ldewangan-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 drivers/gpio/gpio-tegra.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
index c7c175a..6c08613 100644
--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -156,7 +156,7 @@ static int tegra_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
 
 static int tegra_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
-	return irq_find_mapping(irq_domain, offset);
+	return irq_create_mapping(irq_domain, offset);
 }
 
 static struct gpio_chip tegra_gpio_chip = {
-- 
1.7.1.1

[PATCH 2/2] gpio: tegra: fix suspend/resume apis

[Laxman Dewangan]

Following are changes done to fix the suspend/resume
functionality of tegra gpio driver:
- Protect suspend/resume callbacks with CONFIG_PM_SLEEP
  because CONFIG_PM doesn't actually enable any of the PM callbacks, it
  only allows to enable CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME.
  This means if CONFIG_PM is used to protect system sleep callbacks
  then it may end up unreferenced if only runtime PM is enabled.

- Fix the suspend/resume APIs declaration as per callback prototype.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
---
 drivers/gpio/gpio-tegra.c |   18 +++++++++++++-----
 1 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c
index 6c08613..9c1884b 100644
--- a/drivers/gpio/gpio-tegra.c
+++ b/drivers/gpio/gpio-tegra.c
@@ -27,6 +27,7 @@
 #include <linux/module.h>
 #include <linux/irqdomain.h>
 #include <linux/pinctrl/consumer.h>
+#include <linux/pm.h>
 
 #include <asm/mach/irq.h>
 
@@ -64,7 +65,7 @@ struct tegra_gpio_bank {
 	int bank;
 	int irq;
 	spinlock_t lvl_lock[4];
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 	u32 cnf[4];
 	u32 out[4];
 	u32 oe[4];
@@ -285,8 +286,8 @@ static void tegra_gpio_irq_handler(unsigned int irq, struct irq_desc *desc)
 
 }
 
-#ifdef CONFIG_PM
-void tegra_gpio_resume(void)
+#ifdef CONFIG_PM_SLEEP
+static int  tegra_gpio_resume(struct device *dev)
 {
 	unsigned long flags;
 	int b;
@@ -308,9 +309,10 @@ void tegra_gpio_resume(void)
 	}
 
 	local_irq_restore(flags);
+	return 0;
 }
 
-void tegra_gpio_suspend(void)
+static int tegra_gpio_suspend(struct device *dev)
 {
 	unsigned long flags;
 	int b;
@@ -330,6 +332,7 @@ void tegra_gpio_suspend(void)
 		}
 	}
 	local_irq_restore(flags);
+	return 0;
 }
 
 static int tegra_gpio_wake_enable(struct irq_data *d, unsigned int enable)
@@ -345,11 +348,15 @@ static struct irq_chip tegra_gpio_irq_chip = {
 	.irq_mask	= tegra_gpio_irq_mask,
 	.irq_unmask	= tegra_gpio_irq_unmask,
 	.irq_set_type	= tegra_gpio_irq_set_type,
-#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
 	.irq_set_wake	= tegra_gpio_wake_enable,
 #endif
 };
 
+static const struct dev_pm_ops tegra_gpio_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(tegra_gpio_suspend, tegra_gpio_resume)
+};
+
 struct tegra_gpio_soc_config {
 	u32 bank_stride;
 	u32 upper_offset;
@@ -489,6 +496,7 @@ static struct platform_driver tegra_gpio_driver = {
 	.driver		= {
 		.name	= "tegra-gpio",
 		.owner	= THIS_MODULE,
+		.pm	= &tegra_gpio_pm_ops,
 		.of_match_table = tegra_gpio_of_match,
 	},
 	.probe		= tegra_gpio_probe,
-- 
1.7.1.1

Re: [PATCH 2/2] gpio: tegra: fix suspend/resume apis

[Stephen Warren]

On 11/07/2012 08:01 AM, Laxman Dewangan wrote:
> Following are changes done to fix the suspend/resume
> functionality of tegra gpio driver:
> - Protect suspend/resume callbacks with CONFIG_PM_SLEEP
>   because CONFIG_PM doesn't actually enable any of the PM callbacks, it
>   only allows to enable CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME.
>   This means if CONFIG_PM is used to protect system sleep callbacks
>   then it may end up unreferenced if only runtime PM is enabled.
> 
> - Fix the suspend/resume APIs declaration as per callback prototype.

Seems plausible, so this patch,
Acked-by: Stephen Warren <swarren-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

I wonder why the suspend/resume functions weren't actually hooked up
anywhere before. Oh well.

Just one very minor nit below:

> diff --git a/drivers/gpio/gpio-tegra.c b/drivers/gpio/gpio-tegra.c

> +#ifdef CONFIG_PM_SLEEP
> +static int  tegra_gpio_resume(struct device *dev)

There are two spaces after "int" there.

Re: [PATCH 2/2] gpio: tegra: fix suspend/resume apis

[Linus Walleij]

On Wed, Nov 7, 2012 at 4:01 PM, Laxman Dewangan <ldewangan-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> wrote:

> Following are changes done to fix the suspend/resume
> functionality of tegra gpio driver:
> - Protect suspend/resume callbacks with CONFIG_PM_SLEEP
>   because CONFIG_PM doesn't actually enable any of the PM callbacks, it
>   only allows to enable CONFIG_PM_SLEEP and CONFIG_PM_RUNTIME.
>   This means if CONFIG_PM is used to protect system sleep callbacks
>   then it may end up unreferenced if only runtime PM is enabled.
>
> - Fix the suspend/resume APIs declaration as per callback prototype.
>
> Signed-off-by: Laxman Dewangan <ldewangan-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

OK patch applied to my devel branch, with Stephens ACK
and I also fixed the whitespace issue he pointed out.

Yours,
Linus Walleij

Re: [PATCH 1/2] gpio: tegra: create irq mapping in gpio_to_irq

[Stephen Warren]

On 11/07/2012 08:01 AM, Laxman Dewangan wrote:
> The gpio interrupts get mapped linearly and hence the mapping
> of irq need to be created by irq_create_mapping().
> 
> The function gpio_to_irq() returns the irq by irq_find_mapping()
> and so returns 0 as there is no mapping created. Fix the function
> to create mapping when gpio_to_irq() get called.

I'm not convinced this should be needed. tegra_gpio_probe() contains:

>         for (gpio = 0; gpio < tegra_gpio_chip.ngpio; gpio++) {
>                 int irq = irq_create_mapping(irq_domain, gpio);

which should create the mapping for every IRQ.

(although I do think the gpiochip_add() should be moved to the very end
of probe(), I doubt that impacts this issue much)

Re: [PATCH 1/2] gpio: tegra: create irq mapping in gpio_to_irq

[Laxman Dewangan]

On Wednesday 07 November 2012 10:38 PM, Stephen Warren wrote:
> On 11/07/2012 08:01 AM, Laxman Dewangan wrote:
>> The gpio interrupts get mapped linearly and hence the mapping
>> of irq need to be created by irq_create_mapping().
>>
>> The function gpio_to_irq() returns the irq by irq_find_mapping()
>> and so returns 0 as there is no mapping created. Fix the function
>> to create mapping when gpio_to_irq() get called.
> I'm not convinced this should be needed. tegra_gpio_probe() contains:


Oh, yes, I did not observe this code in my review. So this change is not 
resolving any issue.


I think we should move the mapping to gpio_to_irq() rather than doing 
this in probe.