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

From: Jisheng Zhang
Date: Tue Jun 27 2023 - 12:32:38 EST


Commit c4a5153e87fd ("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: c4a5153e87fd ("usb: dwc3: core: Power-off core/PHYs on system_suspend in host mode")
Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 7b2ce013cc5b..16d7a1d1cbfa 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -277,9 +277,9 @@ 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);
--
2.40.1