diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c index 06043c7c31006..d17f6592d86d8 100644 --- a/drivers/usb/host/xhci-mtk.c +++ b/drivers/usb/host/xhci-mtk.c @@ -219,6 +219,19 @@ static int xhci_mtk_host_enable(struct xhci_hcd_mtk *mtk) /* power on and enable u3 ports except skipped ones */ for (i = 0; i < mtk->num_u3_ports; i++) { if ((0x1 << i) & mtk->u3p_dis_msk) { + /* + * Park skipped ports instead of leaving them in + * their power-on default state: the port's PHY may + * be uninitialized or its SerDes lane owned by + * another controller (e.g. PCIe), in which case a + * powered-up port whose MAC clock domain is never + * released from reset can hold the interrupt line + * asserted, getting it disabled by the spurious + * IRQ detector and killing the whole host. + */ + value = readl(&ippc->u3_ctrl_p[i]); + value |= CTRL_U3_PORT_PDN | CTRL_U3_PORT_DIS; + writel(value, &ippc->u3_ctrl_p[i]); u3_ports_disabled++; continue; }