Re: [PATCH v2] usb: ohci-at91: Fix the unhandle interrupt when resume

From: Guiting Shen
Date: Sun Jun 25 2023 - 22:28:50 EST


On Mon, Jun 26, 2023 at 04:04:29AM GMT+8, Alan Stern wrote:
> On Mon, Jun 26, 2023 at 12:15:53AM +0800, Guiting Shen wrote:
>> The ohci_hcd_at91_drv_suspend() sets ohci->rh_state to OHCI_RH_HALTED when
>> suspend which will let the ohci_irq() skip the interrupt after resume. And
>> nobody to handle this interrupt.
>>
>> According to the comment in ohci_hcd_at91_drv_suspend(), it need to reset
>> when resume from suspend(MEM) to fix.
>>
>> Signed-off-by: Guiting Shen <aarongt.shen@xxxxxxxxx>
>> ---
>> drivers/usb/host/ohci-at91.c | 7 ++++++-
>> 1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/host/ohci-at91.c b/drivers/usb/host/ohci-at91.c
>> index b9ce8d80f20b..1a0356d9ea15 100644
>> --- a/drivers/usb/host/ohci-at91.c
>> +++ b/drivers/usb/host/ohci-at91.c
>> @@ -672,7 +672,12 @@ ohci_hcd_at91_drv_resume(struct device *dev)
>> else
>> at91_start_clock(ohci_at91);
>>
>> - ohci_resume(hcd, false);
>> + /*
>> + * need to reset according to the comment of suspend routine,
>> + * otherwise the ohci_irq would skip the interrupt if ohci_state
>> + * was OHCI_RH_HALTED.
>> + */
>> + ohci_resume(hcd, !ohci_at91->wakeup);
>
> This comment doesn't say why the code uses !ohci_at91->wakeup. It
> should explain that. For example:
>
> /*
> * According to the comment in ohci_hcd_at91_drv_suspend()
> * we need to do a reset if the 48-MHz clock was stopped,
> * that is, if ohci_at91->wakeup is clear. Tell ohci_resume()
> * to reset in this case by setting its "hibernated" flag.
> */
>

Ok, Thank you!
Do I send the v3 patch after the merge window close?

--
Regards,
Guiting Shen