Commit 9cfb31e4 authored Nov 04, 2024 by Roger Quadros Committed by Greg Kroah-Hartman Nov 05, 2024

usb: dwc3: fix fault at system suspend if device was already runtime suspended



If the device was already runtime suspended then during system suspend
we cannot access the device registers else it will crash.

Also we cannot access any registers after dwc3_core_exit() on some
platforms so move the dwc3_enable_susphy() call to the top.

Cc: stable@vger.kernel.org # v5.15+
Reported-by: William McVicker <willmcvicker@google.com>
Closes: https://lore.kernel.org/all/ZyVfcUuPq56R2m1Y@google.com


Fixes: 705e3ce3 ("usb: dwc3: core: Fix system suspend on TI AM62 platforms")
Signed-off-by: Roger Quadros <rogerq@kernel.org>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Tested-by: Will McVicker <willmcvicker@google.com>
Link: https://lore.kernel.org/r/20241104-am62-lpm-usb-fix-v1-1-e93df73a4f0d@kernel.org


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 029778a4

drivers/usb/dwc3/core.c

+12 −13

Original line number	Diff line number	Diff line
		@@ -2342,10 +2342,18 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
		u32 reg;
		int i;

		if (!pm_runtime_suspended(dwc->dev) && !PMSG_IS_AUTO(msg)) {
		dwc->susphy_state = (dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)) &
		DWC3_GUSB2PHYCFG_SUSPHY) \|\|
		(dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0)) &
		DWC3_GUSB3PIPECTL_SUSPHY);
		/*
		* TI AM62 platform requires SUSPHY to be
		* enabled for system suspend to work.
		*/
		if (!dwc->susphy_state)
		dwc3_enable_susphy(dwc, true);
		}

		switch (dwc->current_dr_role) {
		case DWC3_GCTL_PRTCAP_DEVICE:
		@@ -2398,15 +2406,6 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
		break;
		}

		if (!PMSG_IS_AUTO(msg)) {
		/*
		* TI AM62 platform requires SUSPHY to be
		* enabled for system suspend to work.
		*/
		if (!dwc->susphy_state)
		dwc3_enable_susphy(dwc, true);
		}

		return 0;
		}