Commit 640cb5f5 authored Jun 28, 2023 by Jisheng Zhang Committed by Greg Kroah-Hartman Aug 11, 2023

usb: dwc3: don't reset device side if dwc3 was configured as host-only



commit e835c0a4e23c38531dcee5ef77e8d1cf462658c7 upstream.

Commit c4a5153e ("usb: dwc3: core: Power-off core/PHYs on
system_suspend in host mode") replaces check for HOST only dr_mode with
current_dr_role. But during booting, the current_dr_role isn't
initialized, thus the device side reset is always issued even if dwc3
was configured as host-only. What's more, on some platforms with host
only dwc3, aways issuing device side reset by accessing device register
block can cause kernel panic.

Fixes: c4a5153e ("usb: dwc3: core: Power-off core/PHYs on system_suspend in host mode")
Cc: stable <stable@kernel.org>
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20230627162018.739-1-jszhang@kernel.org


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

parent a7d080cf

drivers/usb/dwc3/core.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -248,9 +248,9 @@ int dwc3_core_soft_reset(struct dwc3 *dwc)
		/*
		* We're resetting only the device side because, if we're in host mode,
		* XHCI driver will reset the host block. If dwc3 was configured for
		* host-only mode, then we can return early.
		* host-only mode or current role is host, then we can return early.
		*/
		if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST)
		if (dwc->dr_mode == USB_DR_MODE_HOST \|\| dwc->current_dr_role == DWC3_GCTL_PRTCAP_HOST)
		return 0;

		reg = dwc3_readl(dwc->regs, DWC3_DCTL);