Re: [RFC PATCH] mmc: sdhci-of-at91: don't put device in suspend after probe

[Adrian Hunter]

On 10/02/16 14:51, Ludovic Desroches wrote:
> Hi Adrian,
> 
> On Wed, Feb 10, 2016 at 01:50:44PM +0200, Adrian Hunter wrote:
>> On 10/02/16 11:58, Ludovic Desroches wrote:
>>> By putting the device in suspend at the end of the probe, it is
>>> impossible to wake up on non software event such as card
>>> insertion/removal.
>>>
>>> Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
>>> ---
>>>
>>> Hi,
>>>
>>> Since I had no feedback on this topic:
>>> http://permalink.gmane.org/gmane.linux.kernel.mmc/35160
>>>
>>> I would like to no more put the device in suspend at the end of the probe. If
>>> my device is suspended at the end of the probe, I have no issue to resume on
>>> a software event such as mounting my sdcard but hardware event such as card
>>> insertion and removal do not trigger a resume.
>>
>> You can't use runtime PM unless you have a way to wake-up.
>>
> 
> Thanks for your feedback. I am a bit disappointed since Ulf advised me to use
> runtime PM instead of system PM.
> 
>> Currently, sdhci disables card detect interrupts when runtime suspended,
>> and drivers use a card-detect GPIO to wake-up.
>>
> 
> It is what I have seen going through the sdhci layer. So next question is:
> is it normal to not take care of card detect interrupts? We keep enabled
> some IRQs probably for SDIO modules IRQ but not for card detection. I
> don't understand the reason.

Does sdhci-of-at91.c generate card detect interrupts while runtime suspended?