From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Kai-Heng Feng <kai.heng.feng@canonical.com>,
        Mathias Nyman <mathias.nyman@linux.intel.com>
Subject: [PATCH 4.14 37/53] xhci: Remove CONFIG_USB_DEFAULT_PERSIST to prevent xHCI from runtime suspending
Date:   Mon, 13 Dec 2021 10:30:16 +0100
Message-Id: <20211213092929.593946951@linuxfoundation.org>
In-Reply-To: <20211213092928.349556070@linuxfoundation.org>
References: <20211213092928.349556070@linuxfoundation.org>
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From: Kai-Heng Feng <kai.heng.feng@canonical.com>

commit 811ae81320da53a5670c36970cefacca8519f90e upstream.

When the xHCI is quirked with XHCI_RESET_ON_RESUME, runtime resume
routine also resets the controller.

This is bad for USB drivers without reset_resume callback, because
there's no subsequent call of usb_dev_complete() ->
usb_resume_complete() to force rebinding the driver to the device. For
instance, btusb device stops working after xHCI controller is runtime
resumed, if the controlled is quirked with XHCI_RESET_ON_RESUME.

So always take XHCI_RESET_ON_RESUME into account to solve the issue.

Cc: <stable@vger.kernel.org>
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20211210141735.1384209-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/host/xhci.c |    4 ----
 1 file changed, 4 deletions(-)

--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3627,7 +3627,6 @@ static void xhci_free_dev(struct usb_hcd
 	struct xhci_slot_ctx *slot_ctx;
 	int i, ret;
 
-#ifndef CONFIG_USB_DEFAULT_PERSIST
 	/*
 	 * We called pm_runtime_get_noresume when the device was attached.
 	 * Decrement the counter here to allow controller to runtime suspend
@@ -3635,7 +3634,6 @@ static void xhci_free_dev(struct usb_hcd
 	 */
 	if (xhci->quirks & XHCI_RESET_ON_RESUME)
 		pm_runtime_put_noidle(hcd->self.controller);
-#endif
 
 	ret = xhci_check_args(hcd, udev, NULL, 0, true, __func__);
 	/* If the host is halted due to driver unload, we still need to free the
@@ -3790,14 +3788,12 @@ int xhci_alloc_dev(struct usb_hcd *hcd,
 
 	udev->slot_id = slot_id;
 
-#ifndef CONFIG_USB_DEFAULT_PERSIST
 	/*
 	 * If resetting upon resume, we can't put the controller into runtime
 	 * suspend if there is a device attached.
 	 */
 	if (xhci->quirks & XHCI_RESET_ON_RESUME)
 		pm_runtime_get_noresume(hcd->self.controller);
-#endif
 
 	/* Is this a LS or FS device under a HS hub? */
 	/* Hub or peripherial? */