From nobody Sun Dec 22 06:04:01 2024 Received: from cae.in-ulm.de (cae.in-ulm.de [217.10.14.231]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 418201885A2; Thu, 12 Sep 2024 05:44:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.10.14.231 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726119900; cv=none; b=doLafN+lJFvXk72xuIUMFImS8TxDst9vrHHg0xW7KWziI+BLadl1NcQaV4ezb5I50vmoBY+R3TP/rWMIjsR6k6IUaFevSuSnQp9QXoZ1oRC25Yj7WsxXhpHzB+EzWkUPQ8AWUNZBhzbvFzcyhJhaAZyuZnUEWyywIW/a5DSB2gA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726119900; c=relaxed/simple; bh=rOeQorWaZDlaIIJiAOwM/shiKOi3AhhiIX+db/g+M4U=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=AbT81bEkLE6Cp8CB36PxVDbdm2wdOmCdEd5jGi4ohpZbxFpDKXXEYpWx6MVyfr5HqeLUUYNYJy6bDbg+x0rqret0hQri71fu0EUSWug4+Q3jAdKzT8/wq2bOCgC/2qFH4ymnYekrjgchi7sZH8pqYJrHw0QnHxpciS2fr+EHY0M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=c--e.de; spf=pass smtp.mailfrom=c--e.de; arc=none smtp.client-ip=217.10.14.231 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=c--e.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=c--e.de Received: by cae.in-ulm.de (Postfix, from userid 1000) id 7A6721402BA; Thu, 12 Sep 2024 07:44:49 +0200 (CEST) From: "Christian A. Ehrhardt" To: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Cc: "Christian A. Ehrhardt" , Anurag Bijea , Christian Heusel , Heikki Krogerus , Greg Kroah-Hartman , Dmitry Baryshkov , Jameson Thies , Abhishek Pandit-Subedi Subject: [PATCH] usb: typec: ucsi: Fix busy loop on ASUS VivoBooks Date: Thu, 12 Sep 2024 07:44:33 +0200 Message-Id: <20240912054433.721651-1-lk@c--e.de> X-Mailer: git-send-email 2.30.2 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If the busy indicator is set, all other fields in CCI should be clear according to the spec. However, some UCSI implementations do not follow this rule and report bogus data in CCI along with the busy indicator. Ignore the contents of CCI if the busy indicator is set. If a command timeout is hit it is possible that the EVENT_PENDING bit is cleared while connector work is still scheduled which can cause the EVENT_PENDING bit to go out of sync with scheduled connector work. Check and set the EVENT_PENDING bit on entry to ucsi_handle_connector_change() to fix this. Finally, check UCSI_CCI_BUSY before the return code of ->sync_control. This ensures that the command is cancelled even if ->sync_control returns an error (most likely -ETIMEDOUT). Reported-by: Anurag Bijea Closes: https://bugzilla.kernel.org/show_bug.cgi?id=3D219108 Bisected-by: Christian Heusel Tested-by: Anurag Bijea Fixes: de52aca4d9d5 ("usb: typec: ucsi: Never send a lone connector change = ack") Cc: stable@vger.kernel.org Signed-off-by: Christian A. Ehrhardt --- NOTE: Rebased onto usb-next. drivers/usb/typec/ucsi/ucsi.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 35dce4057c25..e0f3925e401b 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -38,6 +38,10 @@ =20 void ucsi_notify_common(struct ucsi *ucsi, u32 cci) { + /* Ignore bogus data in CCI if busy indicator is set. */ + if (cci & UCSI_CCI_BUSY) + return; + if (UCSI_CCI_CONNECTOR(cci)) ucsi_connector_change(ucsi, UCSI_CCI_CONNECTOR(cci)); =20 @@ -103,15 +107,13 @@ static int ucsi_run_command(struct ucsi *ucsi, u64 co= mmand, u32 *cci, return -EINVAL; =20 ret =3D ucsi->ops->sync_control(ucsi, command); - if (ret) - return ret; - - ret =3D ucsi->ops->read_cci(ucsi, cci); - if (ret) - return ret; + if (ucsi->ops->read_cci(ucsi, cci)) + return -EIO; =20 if (*cci & UCSI_CCI_BUSY) return ucsi_run_command(ucsi, UCSI_CANCEL, cci, NULL, 0, false) ?: -EBUS= Y; + if (ret) + return ret; =20 if (!(*cci & UCSI_CCI_COMMAND_COMPLETE)) return -EIO; @@ -1197,6 +1199,10 @@ static void ucsi_handle_connector_change(struct work= _struct *work) =20 mutex_lock(&con->lock); =20 + if (!test_and_set_bit(EVENT_PENDING, &ucsi->flags)) + dev_err_once(ucsi->dev, "%s entered without EVENT_PENDING\n", + __func__); + command =3D UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); =20 ret =3D ucsi_send_command_common(ucsi, command, &con->status, --=20 2.43.0