From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB6C5C47082 for ; Mon, 31 May 2021 16:19:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BF17361374 for ; Mon, 31 May 2021 16:19:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233467AbhEaQUl (ORCPT ); Mon, 31 May 2021 12:20:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:37856 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231810AbhEaOlX (ORCPT ); Mon, 31 May 2021 10:41:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 34D7561C65; Mon, 31 May 2021 13:53:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1622469195; bh=ejMJuLJ0WEYbmwOOtAcmZbty7rI2OOc8/VA/+lJBxP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D7fZA/hitc8KD1ASnSMB7z2qFNIN4CTbAitMilBCmsgvOHo2u6Unp8TBqV+qppCfU zfSHLfwIow6CEIj4GrBScS9HD7pjcSQTM2y/B4x/FTP8T7R60ZfT8b5K5ahvGkKRQv TsWeI/b8Il0WO2Zx3ICX6spVJ7H6KrF190WUB43Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Heikki Krogerus , Benjamin Berg , Bjorn Andersson Subject: [PATCH 5.12 106/296] usb: typec: ucsi: Clear pending after acking connector change Date: Mon, 31 May 2021 15:12:41 +0200 Message-Id: <20210531130707.501215780@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210531130703.762129381@linuxfoundation.org> References: <20210531130703.762129381@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Bjorn Andersson commit 8c9b3caab3ac26db1da00b8117901640c55a69dd upstream. It's possible that the interrupt handler for the UCSI driver signals a connector changes after the handler clears the PENDING bit, but before it has sent the acknowledge request. The result is that the handler is invoked yet again, to ack the same connector change. At least some versions of the Qualcomm UCSI firmware will not handle the second - "spurious" - acknowledgment gracefully. So make sure to not clear the pending flag until the change is acknowledged. Any connector changes coming in after the acknowledgment, that would have the pending flag incorrectly cleared, would afaict be covered by the subsequent connector status check. Fixes: 217504a05532 ("usb: typec: ucsi: Work around PPM losing change information") Cc: stable Reviewed-by: Heikki Krogerus Acked-By: Benjamin Berg Signed-off-by: Bjorn Andersson Link: https://lore.kernel.org/r/20210516040953.622409-1-bjorn.andersson@linaro.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/ucsi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -717,8 +717,8 @@ static void ucsi_handle_connector_change ucsi_send_command(con->ucsi, command, NULL, 0); /* 3. ACK connector change */ - clear_bit(EVENT_PENDING, &ucsi->flags); ret = ucsi_acknowledge_connector_change(ucsi); + clear_bit(EVENT_PENDING, &ucsi->flags); if (ret) { dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret); goto out_unlock;