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

[Wanlong Gao <gaowanlong@cn.fujitsu.com>]

On 10/12/2011 05:39 PM, 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>


Looks good to me. Thanks
Reviewed-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>

> ---
> 
> 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),