usb: host: tegra: Prevent host controller crash when OTG port is used
When a USB device is connected to the OTG port, the tegra_xhci_id_work() routine transitions the PHY to host mode and calls xhci_hub_control() with the SetPortFeature command to enable port power. In certain cases, the XHCI controller may be in a low-power state when this operation occurs. If xhci_hub_control() is invoked while the controller is suspended, the PORTSC register may return 0xFFFFFFFF, indicating a read failure. This causes xhci_hc_died() to be triggered, leading to host controller shutdown. Example backtrace: [ 105.445736] Workqueue: events tegra_xhci_id_work [ 105.445747] dump_backtrace+0x0/0x1e8 [ 105.445759] xhci_hc_died.part.48+0x40/0x270 [ 105.445769] tegra_xhci_set_port_power+0xc0/0x240 [ 105.445774] tegra_xhci_id_work+0x130/0x240 To prevent this, ensure the controller is fully resumed before interacting with hardware registers by calling pm_runtime_get_sync() prior to the host mode transition and xhci_hub_control(). Fixes: f836e784 ("usb: xhci-tegra: Add OTG support") Cc: stable <stable@kernel.org> Signed-off-by:Jim Lin <jilin@nvidia.com> Signed-off-by:
Wayne Chang <waynec@nvidia.com> Link: https://lore.kernel.org/r/20250422114001.126367-1-waynec@nvidia.com Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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