Re: [PATCH v7 2/5] usb: dwc3: core: Host wake up support from system suspend

[Sandeep Maheswaram <sanm@codeaurora.org>]

On 4/28/2021 3:29 PM, Felipe Balbi wrote:
> Hi,
>
> Sandeep Maheswaram <sanm@codeaurora.org> writes:
>> Avoiding phy powerdown when wakeup capable devices are connected
>> by checking phy_power_off flag.
>> Phy should be on to wake up the device from suspend using wakeup capable
>> devices such as keyboard and mouse.
>>
>> Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
>> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
>> ---
>>   drivers/usb/dwc3/core.c | 7 +++++--
>>   1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index b6e53d8..bb414c3 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -1738,7 +1738,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>>   		dwc3_core_exit(dwc);
>>   		break;
>>   	case DWC3_GCTL_PRTCAP_HOST:
>> -		if (!PMSG_IS_AUTO(msg)) {
>> +		if (!PMSG_IS_AUTO(msg) && dwc->phy_power_off) {
> should be able to detect this generically, no? Shouldn't
> device_may_wakeup() be valid here and give you the answer you want?

I think  device_may_wakeup() gives whether the controller is wake up 
capable or not.

But we want to keep phy powered on only when some wakeup capable devices 
(eg:keyboard ,mouse ) are connected to controller.