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

[Hui Wang <jason77.wang@gmail.com>]

Wanlong Gao wrote:
> On 09/30/2011 04:59 PM, Hui Wang wrote:
>
>   
>> Wanlong Gao wrote:
>>     
>>> On 09/30/2011 03:54 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>
>>>> ---
>>>>         
>
>   
>>>   
>>>       
>> The i.MX series kpp is not like other normal kpps on other platforms, 
>> the kpp on the i.MX can detect key event and wake up system from low 
>> power mode even we disable kpp clock. So i choose to unconditionally 
>> disable its clock. I have explain it the commit header.
>>
>> "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.
>> "
>>
>>     
>
>
> I see.
>
>   
>>>> +
>>>> +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;
>>>> +
>>>> +	mutex_lock(&input_dev->mutex);
>>>> +
>>>> +	if (device_may_wakeup(&pdev->dev))
>>>> +		disable_irq_wake(kbd->irq);
>>>> +
>>>> +	if (input_dev->users)
>>>> +		clk_enable(kbd->clk);
>>>> +
>>>> +	mutex_unlock(&input_dev->mutex);
>>>> +
>>>> +	return 0;
>>>> +}
>>>>         
>
>
> But is it need to hold a mutex lock also when *disable_irq_wake()* here ?
>   
Yes, this is a problem, i will address it in the V2.

Thanks,
Hui.
> Thanks
> -Wanlong Gao
>
>