diff mbox

[v2,4/6] gpio: brcmstb: Allow GPIOs to be wakeup sources

Message ID 1432865650-4062-5-git-send-email-gregory.0xf0@gmail.com
State New
Headers show

Commit Message

Gregory Fong May 29, 2015, 2:14 a.m. UTC
Several drivers (e.g. gpio-keys) allow for GPIOs to be configured as
wakeup sources, and this GPIO controller supports that through a
separate interrupt path.

The de-facto standard DT property "wakeup-source" is checked, since
that indicates whether the GPIO controller hardware can wake.  Uses
the IRQCHIP_MASK_ON_SUSPEND irq_chip flag because UPG GIO doesn't have
any of its own wakeup source configuration.

Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
---
New in v2.

 drivers/gpio/gpio-brcmstb.c | 53 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

Comments

Brian Norris May 30, 2015, 12:43 a.m. UTC | #1
On Thu, May 28, 2015 at 07:14:08PM -0700, Gregory Fong wrote:
> Several drivers (e.g. gpio-keys) allow for GPIOs to be configured as
> wakeup sources, and this GPIO controller supports that through a
> separate interrupt path.
> 
> The de-facto standard DT property "wakeup-source" is checked, since
> that indicates whether the GPIO controller hardware can wake.  Uses
> the IRQCHIP_MASK_ON_SUSPEND irq_chip flag because UPG GIO doesn't have
> any of its own wakeup source configuration.
> 
> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
> ---
> New in v2.
> 
>  drivers/gpio/gpio-brcmstb.c | 53 +++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
> 
> diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
> index b9962ff..2598c1e 100644
> --- a/drivers/gpio/gpio-brcmstb.c
> +++ b/drivers/gpio/gpio-brcmstb.c
> @@ -19,6 +19,7 @@
>  #include <linux/basic_mmio_gpio.h>
>  #include <linux/irqdomain.h>
>  #include <linux/irqchip/chained_irq.h>
> +#include <linux/interrupt.h>
>  
>  #define GIO_BANK_SIZE           0x20
>  #define GIO_ODEN(bank)          (((bank) * GIO_BANK_SIZE) + 0x00)
> @@ -48,6 +49,7 @@ struct brcmstb_gpio_priv {
>  	struct irq_domain *irq_domain;
>  	int parent_irq;
>  	int gpio_base;
> +	int parent_wake_irq;
>  };
>  
>  #define MAX_GPIO_PER_BANK           32
> @@ -183,6 +185,31 @@ static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
>  	return 0;
>  }
>  
> +static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
> +{
> +	struct brcmstb_gpio_bank *bank = irq_data_get_irq_chip_data(d);
> +	struct brcmstb_gpio_priv *priv = bank->parent_priv;
> +
> +	/*
> +	 * Only enable wake IRQ once for however many hwirqs can wake
> +	 * since they all use the same wake IRQ.  Mask will be set
> +	 * up appropriately thanks to IRQCHIP_MASK_ON_SUSPEND flag.
> +	 */
> +	if (enable)
> +		enable_irq_wake(priv->parent_wake_irq);
> +	else
> +		disable_irq_wake(priv->parent_wake_irq);
> +	return 0;
> +}
> +
> +static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
> +{
> +	struct brcmstb_gpio_priv *priv = data;
> +
> +	pm_wakeup_event(&priv->pdev->dev, 0);
> +	return IRQ_HANDLED;
> +}
> +
>  static void brcmstb_gpio_irq_bank_handler(int irq,
>  		struct brcmstb_gpio_bank *bank)
>  {
> @@ -369,6 +396,32 @@ static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
>  	priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
>  	priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
>  	priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
> +
> +	/* Ensures that all non-wakeup IRQs are disabled at suspend */
> +	priv->irq_chip.flags = IRQCHIP_MASK_ON_SUSPEND;
> +
> +	if (IS_ENABLED(CONFIG_PM_SLEEP) &&
> +			of_get_property(np, "wakeup-source", NULL)) {

of_property_read_bool()?

> +		priv->parent_wake_irq = platform_get_irq(pdev, 1);
> +		if (priv->parent_wake_irq < 0)  {
> +			dev_warn(dev,
> +				"Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
> +		} else {
> +			int err = devm_request_irq(dev, priv->parent_wake_irq,
> +					brcmstb_gpio_wake_irq_handler, 0,
> +					"brcmstb-gpio-wake", priv);
> +
> +			if (err < 0) {
> +				dev_err(dev, "Couldn't request wake IRQ");
> +				return err;
> +			}
> +
> +			device_set_wakeup_capable(dev, true);
> +			device_wakeup_enable(dev);

Might want to move these two lines above the devm_request_irq(), so that
you're ready to record PM events immediately at probe time. This is
important when waking from S5 states, where we sometimes want to be able
to check the /sys/devices/.../wakeup_count stats to see what woke us up.

> +			priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
> +		}
> +	}
> +
>  	priv->irq_domain =
>  		irq_domain_add_linear(np, priv->num_gpios,
>  				      &brcmstb_gpio_irq_domain_ops,

With that:

Reviewed-by: Brian Norris <computersforpeace@gmail.com>
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Linus Walleij June 2, 2015, 1:45 p.m. UTC | #2
On Fri, May 29, 2015 at 4:14 AM, Gregory Fong <gregory.0xf0@gmail.com> wrote:

> Several drivers (e.g. gpio-keys) allow for GPIOs to be configured as
> wakeup sources, and this GPIO controller supports that through a
> separate interrupt path.
>
> The de-facto standard DT property "wakeup-source" is checked, since
> that indicates whether the GPIO controller hardware can wake.  Uses
> the IRQCHIP_MASK_ON_SUSPEND irq_chip flag because UPG GIO doesn't have
> any of its own wakeup source configuration.
>
> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>

(...)
> +       if (enable)
> +               enable_irq_wake(priv->parent_wake_irq);
> +       else
> +               disable_irq_wake(priv->parent_wake_irq);
> +       return 0;

No error handling? If the code assumes these calls will
always succeed, atleast write that in a comment.

Yours,
Linus Walleij
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Gregory Fong June 2, 2015, 5:27 p.m. UTC | #3
On Fri, May 29, 2015 at 5:43 PM, Brian Norris
<computersforpeace@gmail.com> wrote:
> On Thu, May 28, 2015 at 07:14:08PM -0700, Gregory Fong wrote:
>> Several drivers (e.g. gpio-keys) allow for GPIOs to be configured as
>> wakeup sources, and this GPIO controller supports that through a
>> separate interrupt path.
>>
>> The de-facto standard DT property "wakeup-source" is checked, since
>> that indicates whether the GPIO controller hardware can wake.  Uses
>> the IRQCHIP_MASK_ON_SUSPEND irq_chip flag because UPG GIO doesn't have
>> any of its own wakeup source configuration.
>>
>> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
>> ---
>> New in v2.
>>
>>  drivers/gpio/gpio-brcmstb.c | 53 +++++++++++++++++++++++++++++++++++++++++++++
>>  1 file changed, 53 insertions(+)
>>
>> diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
>> index b9962ff..2598c1e 100644
>> --- a/drivers/gpio/gpio-brcmstb.c
>> +++ b/drivers/gpio/gpio-brcmstb.c
>> [...]
>> @@ -369,6 +396,32 @@ static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
>>       priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
>>       priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
>>       priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
>> +
>> +     /* Ensures that all non-wakeup IRQs are disabled at suspend */
>> +     priv->irq_chip.flags = IRQCHIP_MASK_ON_SUSPEND;
>> +
>> +     if (IS_ENABLED(CONFIG_PM_SLEEP) &&
>> +                     of_get_property(np, "wakeup-source", NULL)) {
>
> of_property_read_bool()?

Will change.

>
>> +             priv->parent_wake_irq = platform_get_irq(pdev, 1);
>> +             if (priv->parent_wake_irq < 0)  {
>> +                     dev_warn(dev,
>> +                             "Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
>> +             } else {
>> +                     int err = devm_request_irq(dev, priv->parent_wake_irq,
>> +                                     brcmstb_gpio_wake_irq_handler, 0,
>> +                                     "brcmstb-gpio-wake", priv);
>> +
>> +                     if (err < 0) {
>> +                             dev_err(dev, "Couldn't request wake IRQ");
>> +                             return err;
>> +                     }
>> +
>> +                     device_set_wakeup_capable(dev, true);
>> +                     device_wakeup_enable(dev);
>
> Might want to move these two lines above the devm_request_irq(), so that
> you're ready to record PM events immediately at probe time. This is
> important when waking from S5 states, where we sometimes want to be able
> to check the /sys/devices/.../wakeup_count stats to see what woke us up.

Makes sense.  We'll also need a reboot notifier for S5 to work.

>
>> +                     priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
>> +             }
>> +     }
>> +
>>       priv->irq_domain =
>>               irq_domain_add_linear(np, priv->num_gpios,
>>                                     &brcmstb_gpio_irq_domain_ops,
>
> With that:
>
> Reviewed-by: Brian Norris <computersforpeace@gmail.com>

Thanks,
Gregory
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Gregory Fong June 2, 2015, 5:27 p.m. UTC | #4
On Tue, Jun 2, 2015 at 6:45 AM, Linus Walleij <linus.walleij@linaro.org> wrote:
> On Fri, May 29, 2015 at 4:14 AM, Gregory Fong <gregory.0xf0@gmail.com> wrote:
>
>> Several drivers (e.g. gpio-keys) allow for GPIOs to be configured as
>> wakeup sources, and this GPIO controller supports that through a
>> separate interrupt path.
>>
>> The de-facto standard DT property "wakeup-source" is checked, since
>> that indicates whether the GPIO controller hardware can wake.  Uses
>> the IRQCHIP_MASK_ON_SUSPEND irq_chip flag because UPG GIO doesn't have
>> any of its own wakeup source configuration.
>>
>> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
>
> (...)
>> +       if (enable)
>> +               enable_irq_wake(priv->parent_wake_irq);
>> +       else
>> +               disable_irq_wake(priv->parent_wake_irq);
>> +       return 0;
>
> No error handling? If the code assumes these calls will
> always succeed, atleast write that in a comment.

Will add error handling.

Thanks,
Gregory
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diff mbox

Patch

diff --git a/drivers/gpio/gpio-brcmstb.c b/drivers/gpio/gpio-brcmstb.c
index b9962ff..2598c1e 100644
--- a/drivers/gpio/gpio-brcmstb.c
+++ b/drivers/gpio/gpio-brcmstb.c
@@ -19,6 +19,7 @@ 
 #include <linux/basic_mmio_gpio.h>
 #include <linux/irqdomain.h>
 #include <linux/irqchip/chained_irq.h>
+#include <linux/interrupt.h>
 
 #define GIO_BANK_SIZE           0x20
 #define GIO_ODEN(bank)          (((bank) * GIO_BANK_SIZE) + 0x00)
@@ -48,6 +49,7 @@  struct brcmstb_gpio_priv {
 	struct irq_domain *irq_domain;
 	int parent_irq;
 	int gpio_base;
+	int parent_wake_irq;
 };
 
 #define MAX_GPIO_PER_BANK           32
@@ -183,6 +185,31 @@  static int brcmstb_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 	return 0;
 }
 
+static int brcmstb_gpio_irq_set_wake(struct irq_data *d, unsigned int enable)
+{
+	struct brcmstb_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+	struct brcmstb_gpio_priv *priv = bank->parent_priv;
+
+	/*
+	 * Only enable wake IRQ once for however many hwirqs can wake
+	 * since they all use the same wake IRQ.  Mask will be set
+	 * up appropriately thanks to IRQCHIP_MASK_ON_SUSPEND flag.
+	 */
+	if (enable)
+		enable_irq_wake(priv->parent_wake_irq);
+	else
+		disable_irq_wake(priv->parent_wake_irq);
+	return 0;
+}
+
+static irqreturn_t brcmstb_gpio_wake_irq_handler(int irq, void *data)
+{
+	struct brcmstb_gpio_priv *priv = data;
+
+	pm_wakeup_event(&priv->pdev->dev, 0);
+	return IRQ_HANDLED;
+}
+
 static void brcmstb_gpio_irq_bank_handler(int irq,
 		struct brcmstb_gpio_bank *bank)
 {
@@ -369,6 +396,32 @@  static int brcmstb_gpio_irq_setup(struct platform_device *pdev,
 	priv->irq_chip.irq_mask = brcmstb_gpio_irq_mask;
 	priv->irq_chip.irq_unmask = brcmstb_gpio_irq_unmask;
 	priv->irq_chip.irq_set_type = brcmstb_gpio_irq_set_type;
+
+	/* Ensures that all non-wakeup IRQs are disabled at suspend */
+	priv->irq_chip.flags = IRQCHIP_MASK_ON_SUSPEND;
+
+	if (IS_ENABLED(CONFIG_PM_SLEEP) &&
+			of_get_property(np, "wakeup-source", NULL)) {
+		priv->parent_wake_irq = platform_get_irq(pdev, 1);
+		if (priv->parent_wake_irq < 0)  {
+			dev_warn(dev,
+				"Couldn't get wake IRQ - GPIOs will not be able to wake from sleep");
+		} else {
+			int err = devm_request_irq(dev, priv->parent_wake_irq,
+					brcmstb_gpio_wake_irq_handler, 0,
+					"brcmstb-gpio-wake", priv);
+
+			if (err < 0) {
+				dev_err(dev, "Couldn't request wake IRQ");
+				return err;
+			}
+
+			device_set_wakeup_capable(dev, true);
+			device_wakeup_enable(dev);
+			priv->irq_chip.irq_set_wake = brcmstb_gpio_irq_set_wake;
+		}
+	}
+
 	priv->irq_domain =
 		irq_domain_add_linear(np, priv->num_gpios,
 				      &brcmstb_gpio_irq_domain_ops,