usb: xhci-dwc3: Call xhci_deregister() before asserting reset

Reorder the remove path to deregister the controller first (and return
early on failure), then shut down PHY/clocks and finally assert reset.

This prevents register reads/writes after reset and avoids undefined
behavior.

Signed-off-by: Boon Khai Ng <boon.khai.ng@altera.com>
Reviewed-by: Marek Vasut <marek.vasut@mailbox.org>

diff --git a/drivers/usb/host/xhci-dwc3.c b/drivers/usb/host/xhci-dwc3.c
index 8ad07a4b98c9574a5fa0cbfe83f5567e0f49f364..3504a7cf42ce229b38be96477999ba9787f3a2d6 100644 (file)
--- a/drivers/usb/host/xhci-dwc3.c
+++ b/drivers/usb/host/xhci-dwc3.c
@@ -226,6 +226,11 @@ static int xhci_dwc3_probe(struct udevice *dev)
 static int xhci_dwc3_remove(struct udevice *dev)
 {
        struct xhci_dwc3_plat *plat = dev_get_plat(dev);
+       int ret;
+
+       ret = xhci_deregister(dev);
+       if (ret)
+               return ret;
 
        dwc3_shutdown_phy(dev, &plat->phys);
 
@@ -233,7 +238,7 @@ static int xhci_dwc3_remove(struct udevice *dev)
 
        reset_release_bulk(&plat->resets);
 
-       return xhci_deregister(dev);
+       return 0;
 }
 
 static const struct udevice_id xhci_dwc3_ids[] = {