From 2d44ee69e6f51751b6caaa0eb52a21f3788c8072 Mon Sep 17 00:00:00 2001 From: Jim Lin Date: Tue, 22 Apr 2025 19:40:01 +0800 Subject: [PATCH] usb: host: tegra: Prevent host controller crash when OTG port is used commit 732f35cf8bdfece582f6e4a9c659119036577308 upstream. 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: f836e7843036 ("usb: xhci-tegra: Add OTG support") Cc: stable Signed-off-by: Jim Lin Signed-off-by: Wayne Chang Link: https://lore.kernel.org/r/20250422114001.126367-1-waynec@nvidia.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-tegra.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c index 76f228e7443c..89b3079194d7 100644 --- a/drivers/usb/host/xhci-tegra.c +++ b/drivers/usb/host/xhci-tegra.c @@ -1363,6 +1363,7 @@ static void tegra_xhci_id_work(struct work_struct *work) tegra->otg_usb3_port = tegra_xusb_padctl_get_usb3_companion(tegra->padctl, tegra->otg_usb2_port); + pm_runtime_get_sync(tegra->dev); if (tegra->host_mode) { /* switch to host mode */ if (tegra->otg_usb3_port >= 0) { @@ -1392,6 +1393,7 @@ static void tegra_xhci_id_work(struct work_struct *work) } tegra_xhci_set_port_power(tegra, true, true); + pm_runtime_mark_last_busy(tegra->dev); } else { if (tegra->otg_usb3_port >= 0) @@ -1399,6 +1401,7 @@ static void tegra_xhci_id_work(struct work_struct *work) tegra_xhci_set_port_power(tegra, true, false); } + pm_runtime_put_autosuspend(tegra->dev); } #if IS_ENABLED(CONFIG_PM) || IS_ENABLED(CONFIG_PM_SLEEP)