Date:   Wed, 19 Jan 2022 14:40:13 +0800
Message-Id: <20220119064013.1381172-1-pumahsu@google.com>
Mime-Version: 1.0
Subject: [PATCH v5] xhci: re-initialize the HC during resume if HCE was set
From:   Puma Hsu <pumahsu@google.com>
To:     mathias.nyman@intel.com, gregkh@linuxfoundation.org
Cc:     s.shtylyov@omp.ru, albertccwang@google.com,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        Puma Hsu <pumahsu@google.com>, stable@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

When HCE(Host Controller Error) is set, it means an internal
error condition has been detected. Software needs to re-initialize
the HC, so add this check in xhci resume.

Cc: stable@vger.kernel.org
Signed-off-by: Puma Hsu <pumahsu@google.com>
---
v2: Follow Sergey Shtylyov <s.shtylyov@omp.ru>'s comment.
v3: Add stable@vger.kernel.org for stable release.
v4: Refine the commit message.
v5: Add a debug log. Follow Mathias Nyman <mathias.nyman@linux.intel.com>'s comment.

 drivers/usb/host/xhci.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index dc357cabb265..41f594f0f73f 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1146,8 +1146,10 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		temp = readl(&xhci->op_regs->status);
 	}
 
-	/* If restore operation fails, re-initialize the HC during resume */
-	if ((temp & STS_SRE) || hibernated) {
+	/* If restore operation fails or HC error is detected, re-initialize the HC during resume */
+	if ((temp & (STS_SRE | STS_HCE)) || hibernated) {
+		xhci_warn(xhci, "re-initialize HC during resume, USBSTS:%s\n",
+			  xhci_decode_usbsts(str, temp));
 
 		if ((xhci->quirks & XHCI_COMP_MODE_QUIRK) &&
 				!(xhci_all_ports_seen_u0(xhci))) {
-- 
2.34.1.703.g22d0c6ccf7-goog