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 211E2C4320E for ; Wed, 1 Sep 2021 12:45:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0BA8660F56 for ; Wed, 1 Sep 2021 12:45:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344513AbhIAMqg (ORCPT ); Wed, 1 Sep 2021 08:46:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:43102 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345138AbhIAMkx (ORCPT ); Wed, 1 Sep 2021 08:40:53 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DADBB61183; Wed, 1 Sep 2021 12:37:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1630499825; bh=kHchV+KwZwfPlVmQdaqFWb9t3kmZdUgkIwJNkQdUk+w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=v80J85u8YrxW2YztoOPUH7EfWWuKBdWsHr+bR5ufrh6IODXsqSC02zjN3L0P4ewun wh8C7fTqai7GCuc5ZrxLAH/MdOM1TwSt20F7efh57O08QLv/A3/sRSaC4yb1iC59Yq 02/VzPxPNZdoX1m8i2XRDn5RkEqwcwTpEOlKcFfo= 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 5.10 094/103] usb: typec: ucsi: Clear pending after acking connector change Date: Wed, 1 Sep 2021 14:28:44 +0200 Message-Id: <20210901122303.692592741@linuxfoundation.org> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20210901122300.503008474@linuxfoundation.org> References: <20210901122300.503008474@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 --- 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 @@ -703,8 +703,8 @@ 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;