[PATCH v2] input/imx_keypad: add pm suspend and resume functions

[PATCH v2] input/imx_keypad: add pm suspend and resume functions

[Hui Wang]

The imx_keypad driver is set wake capable in the imx_keypad_probe(),
but it doesn't implement suspend and reusme callback interface.

>From the i.MX series MCU Reference Manual, the kpp (keypad port) is
a major wake up source which can detect any key press even in low
power modes and even when there is no clock.

Now add suspend and resume callback functions for this driver.

Signed-off-by: Hui Wang <jason77.wang@gmail.com>
---

Sorry for resending this patch, the previous sent patch with [v2]
as a prefix, i am afraid that patch was filtered out from mailing list.
Now resending this patch with [PATCH v2] as a prefix.

In the V2:
1) add a check for input->users before disable clock.
2) add mutex_lock/unlock to protect input->users checking.
3) use SIMPLE_DEV_PM_OPS.

 drivers/input/keyboard/imx_keypad.c |   46 +++++++++++++++++++++++++++++++++++
 1 files changed, 46 insertions(+), 0 deletions(-)

diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
index d92c15c..c43fa97 100644
--- a/drivers/input/keyboard/imx_keypad.c
+++ b/drivers/input/keyboard/imx_keypad.c
@@ -567,10 +567,56 @@ static int __devexit imx_keypad_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM
+static int imx_kbd_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_keypad *kbd = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = kbd->input_dev;
+
+	/* imx kbd can wake up system even clock is disabled */
+	mutex_lock(&input_dev->mutex);
+
+	if (input_dev->users)
+		clk_disable(kbd->clk);
+
+	mutex_unlock(&input_dev->mutex);
+
+	if (device_may_wakeup(&pdev->dev))
+		enable_irq_wake(kbd->irq);
+
+	return 0;
+}
+
+static int imx_kbd_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct imx_keypad *kbd = platform_get_drvdata(pdev);
+	struct input_dev *input_dev = kbd->input_dev;
+
+	if (device_may_wakeup(&pdev->dev))
+		disable_irq_wake(kbd->irq);
+
+	mutex_lock(&input_dev->mutex);
+
+	if (input_dev->users)
+		clk_enable(kbd->clk);
+
+	mutex_unlock(&input_dev->mutex);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(imx_kbd_pm_ops, imx_kbd_suspend, imx_kbd_resume);
+#endif
+
 static struct platform_driver imx_keypad_driver = {
 	.driver		= {
 		.name	= "imx-keypad",
 		.owner	= THIS_MODULE,
+#ifdef CONFIG_PM
+		.pm	= &imx_kbd_pm_ops,
+#endif
 	},
 	.probe		= imx_keypad_probe,
 	.remove		= __devexit_p(imx_keypad_remove),
-- 
1.7.6

Re: [PATCH v2] input/imx_keypad: add pm suspend and resume functions

[Sascha Hauer]

On Thu, Oct 13, 2011 at 10:13:33AM +0800, Hui Wang wrote:
> The imx_keypad driver is set wake capable in the imx_keypad_probe(),
> but it doesn't implement suspend and reusme callback interface.
> 
> From the i.MX series MCU Reference Manual, the kpp (keypad port) is
> a major wake up source which can detect any key press even in low
> power modes and even when there is no clock.
> 
> Now add suspend and resume callback functions for this driver.
> 
> Signed-off-by: Hui Wang <jason77.wang@gmail.com>
> ---
> 
> Sorry for resending this patch, the previous sent patch with [v2]
> as a prefix, i am afraid that patch was filtered out from mailing list.
> Now resending this patch with [PATCH v2] as a prefix.
> 
> In the V2:
> 1) add a check for input->users before disable clock.
> 2) add mutex_lock/unlock to protect input->users checking.
> 3) use SIMPLE_DEV_PM_OPS.
> 
>  drivers/input/keyboard/imx_keypad.c |   46 +++++++++++++++++++++++++++++++++++
>  1 files changed, 46 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
> index d92c15c..c43fa97 100644
> --- a/drivers/input/keyboard/imx_keypad.c
> +++ b/drivers/input/keyboard/imx_keypad.c
> @@ -567,10 +567,56 @@ static int __devexit imx_keypad_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +#ifdef CONFIG_PM
> +static int imx_kbd_suspend(struct device *dev)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct imx_keypad *kbd = platform_get_drvdata(pdev);
> +	struct input_dev *input_dev = kbd->input_dev;
> +
> +	/* imx kbd can wake up system even clock is disabled */
> +	mutex_lock(&input_dev->mutex);
> +
> +	if (input_dev->users)
> +		clk_disable(kbd->clk);
> +
> +	mutex_unlock(&input_dev->mutex);
> +
> +	if (device_may_wakeup(&pdev->dev))
> +		enable_irq_wake(kbd->irq);

enable_irq_wake can fail. More specifically it *will* fail on all non
tzic i.MX boards as this function is not yet implemented for the avic
irq controller.
You should check the return value.

Sascha



-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH v2] input/imx_keypad: add pm suspend and resume functions

[Hui Wang]

Sascha Hauer wrote:
> On Thu, Oct 13, 2011 at 10:13:33AM +0800, Hui Wang wrote:
>   
>> The imx_keypad driver is set wake capable in the imx_keypad_probe(),
>> but it doesn't implement suspend and reusme callback interface.
>>
>> From the i.MX series MCU Reference Manual, the kpp (keypad port) is
>> a major wake up source which can detect any key press even in low
>> power modes and even when there is no clock.
>>
>> Now add suspend and resume callback functions for this driver.
>>
>> Signed-off-by: Hui Wang <jason77.wang@gmail.com>
>> ---
>>
>> Sorry for resending this patch, the previous sent patch with [v2]
>> as a prefix, i am afraid that patch was filtered out from mailing list.
>> Now resending this patch with [PATCH v2] as a prefix.
>>
>> In the V2:
>> 1) add a check for input->users before disable clock.
>> 2) add mutex_lock/unlock to protect input->users checking.
>> 3) use SIMPLE_DEV_PM_OPS.
>>
>>  drivers/input/keyboard/imx_keypad.c |   46 +++++++++++++++++++++++++++++++++++
>>  1 files changed, 46 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
>> index d92c15c..c43fa97 100644
>> --- a/drivers/input/keyboard/imx_keypad.c
>> +++ b/drivers/input/keyboard/imx_keypad.c
>> @@ -567,10 +567,56 @@ static int __devexit imx_keypad_remove(struct platform_device *pdev)
>>  	return 0;
>>  }
>>  
>> +#ifdef CONFIG_PM
>> +static int imx_kbd_suspend(struct device *dev)
>> +{
>> +	struct platform_device *pdev = to_platform_device(dev);
>> +	struct imx_keypad *kbd = platform_get_drvdata(pdev);
>> +	struct input_dev *input_dev = kbd->input_dev;
>> +
>> +	/* imx kbd can wake up system even clock is disabled */
>> +	mutex_lock(&input_dev->mutex);
>> +
>> +	if (input_dev->users)
>> +		clk_disable(kbd->clk);
>> +
>> +	mutex_unlock(&input_dev->mutex);
>> +
>> +	if (device_may_wakeup(&pdev->dev))
>> +		enable_irq_wake(kbd->irq);
>>     
>
> enable_irq_wake can fail. More specifically it *will* fail on all non
> tzic i.MX boards as this function is not yet implemented for the avic
> irq controller.
> You should check the return value.
>
>   
Hi Sascha,

I have sent a patch to change plat-mxc/avic.c to use generic irq chip, 
in this patch, two lines to handle wakeup_set issues:

gc->wake_enabled = IRQ_MSK(32);
ct->chip.irq_set_wake = irq_gc_set_wake;

These two lines will make enable_irq_wake successful unconditionally.

And i recall you have sent this patch to Arnd through a pull request.

Thanks,
Hui.
> Sascha
>
>
>
>   

Re: [PATCH v2] input/imx_keypad: add pm suspend and resume functions

[Sascha Hauer]

On Wed, Oct 26, 2011 at 04:41:41PM +0800, Hui Wang wrote:
> Sascha Hauer wrote:
> >On Thu, Oct 13, 2011 at 10:13:33AM +0800, Hui Wang wrote:
> >>The imx_keypad driver is set wake capable in the imx_keypad_probe(),
> >>but it doesn't implement suspend and reusme callback interface.
> >>
> >>From the i.MX series MCU Reference Manual, the kpp (keypad port) is
> >>a major wake up source which can detect any key press even in low
> >>power modes and even when there is no clock.
> >>
> >>Now add suspend and resume callback functions for this driver.
> >>
> >>Signed-off-by: Hui Wang <jason77.wang@gmail.com>
> >>---
> >>
> >>Sorry for resending this patch, the previous sent patch with [v2]
> >>as a prefix, i am afraid that patch was filtered out from mailing list.
> >>Now resending this patch with [PATCH v2] as a prefix.
> >>
> >>In the V2:
> >>1) add a check for input->users before disable clock.
> >>2) add mutex_lock/unlock to protect input->users checking.
> >>3) use SIMPLE_DEV_PM_OPS.
> >>
> >> drivers/input/keyboard/imx_keypad.c |   46 +++++++++++++++++++++++++++++++++++
> >> 1 files changed, 46 insertions(+), 0 deletions(-)
> >>
> >>diff --git a/drivers/input/keyboard/imx_keypad.c b/drivers/input/keyboard/imx_keypad.c
> >>index d92c15c..c43fa97 100644
> >>--- a/drivers/input/keyboard/imx_keypad.c
> >>+++ b/drivers/input/keyboard/imx_keypad.c
> >>@@ -567,10 +567,56 @@ static int __devexit imx_keypad_remove(struct platform_device *pdev)
> >> 	return 0;
> >> }
> >>+#ifdef CONFIG_PM
> >>+static int imx_kbd_suspend(struct device *dev)
> >>+{
> >>+	struct platform_device *pdev = to_platform_device(dev);
> >>+	struct imx_keypad *kbd = platform_get_drvdata(pdev);
> >>+	struct input_dev *input_dev = kbd->input_dev;
> >>+
> >>+	/* imx kbd can wake up system even clock is disabled */
> >>+	mutex_lock(&input_dev->mutex);
> >>+
> >>+	if (input_dev->users)
> >>+		clk_disable(kbd->clk);
> >>+
> >>+	mutex_unlock(&input_dev->mutex);
> >>+
> >>+	if (device_may_wakeup(&pdev->dev))
> >>+		enable_irq_wake(kbd->irq);
> >
> >enable_irq_wake can fail. More specifically it *will* fail on all non
> >tzic i.MX boards as this function is not yet implemented for the avic
> >irq controller.
> >You should check the return value.
> >
> Hi Sascha,
> 
> I have sent a patch to change plat-mxc/avic.c to use generic irq
> chip, in this patch, two lines to handle wakeup_set issues:
> 
> gc->wake_enabled = IRQ_MSK(32);
> ct->chip.irq_set_wake = irq_gc_set_wake;
> 
> These two lines will make enable_irq_wake successful unconditionally.
> 
> And i recall you have sent this patch to Arnd through a pull request.

Ok, so currently this function can't fail, but this a very bad excuse for
not checking error values.

Sascha


-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |