Messages in this thread | | | Date | Thu, 14 Jul 2022 20:33:28 +0530 | Subject | Re: [PATCH] usb: dwc3: qcom: Defer dwc3-qcom probe if dwc3 isn't probed properly | From | Krishna Kurapati PSSNV <> |
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On 7/14/2022 8:31 PM, Greg Kroah-Hartman wrote: > On Thu, Jul 14, 2022 at 08:25:16PM +0530, Krishna Kurapati wrote: >> On SC7180 devices, it is observed that dwc3 probing is deferred >> because device_links_check_suppliers() finds that '88e3000.phy' >> isn't ready yet. >> >> As a part of its probe call, dwc3-qcom driver checks if dwc3 core >> is wakeup capable or not. If the dwc3 core is wakeup capable, driver >> configures dwc-qcom's power domain to be always ON. Also it configures >> dp/dm interrupts accordingly to support wakeup from system suspend. >> >> More info regarding the same can be found at: >> commit d9be8d5c5b03 ("usb: dwc3: qcom: Keep power domain on to retain controller status" >> commit 6895ea55c385 ("usb: dwc3: qcom: Configure wakeup interrupts during suspend") >> >> In the event, dwc3 probe gets deferred and is processed after dwc3-qcom >> probe, driver ends up reading the wakeup capability of dwc3 core as false >> leading to instability in suspend/resume path. >> >> To avoid this scenario, ensure dwc3_probe is successful by checking >> if appropriate driver is assigned to it or not after the of_platform_populate >> call. If it isn't then defer dwc3-qcom probe as well. >> >> Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com> >> --- >> drivers/usb/dwc3/dwc3-qcom.c | 3 +++ >> 1 file changed, 3 insertions(+) > I got 2 different copies of this change, what's the difference? > > confused, > > greg k-h Sorry Greg, My bad, I thought the mail sending failed the first time. So I sent the same patch second time. Sorry for the confusion. Regards, Krishna,
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