[PATCH] xhci: Reset controller on xhci shutdown

[wenxiong]

From: Wen Xiong <wenxiong@xxxxxxxxxxxxx>

Fixes kexec boot. Without a hard reset, some USB chips will fail to
initialize in a kexec booted kernel.

Signed-off-by: Brian King <brking@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Samuel Mendoza-Jonas <sam@xxxxxxxxxxxxxxxx>
Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
Signed-off-by: Wen Xiong <wenxiong@xxxxxxxxxxxxx>
---
 drivers/usb/host/xhci.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index a9e47e178c28..364bd61a4bd7 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -781,6 +781,9 @@ void xhci_shutdown(struct usb_hcd *hcd)
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"xhci_shutdown completed - status = %x",
 			readl(&xhci->op_regs->status));
+
+	/* TI XHCI controllers do not come back after kexec without this hack */
+	pci_reset_function_locked(to_pci_dev(hcd->self.sysdev));
 }
 EXPORT_SYMBOL_GPL(xhci_shutdown);
 
-- 
2.52.0