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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 560E1C49ED7 for ; Fri, 13 Sep 2019 13:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2DEC6214AF for ; Fri, 13 Sep 2019 13:16:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380586; bh=ska6GvcMvDccfwAgcRVlSXG3/h/lqthHXrPwemOftNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2K3fWfOYv2+4dH6JmZTAyuFACtgBlk2KHYLmFCEbhoD//Qy0PeUKTj5hAGEI36MVF 0fmjYCBbeljMNUbXgWIuU1cBmZFsouHsrmZz/MaqjCzu4daJpqdDH/f9sHkw40pDL7 fZfMdNJpmNLjYgZ7uzM0r46MLCQOS+gb6bFSsGG0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388198AbfIMNQZ (ORCPT ); Fri, 13 Sep 2019 09:16:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:43032 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388921AbfIMNQW (ORCPT ); Fri, 13 Sep 2019 09:16:22 -0400 Received: from localhost (unknown [104.132.45.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 274FC20717; Fri, 13 Sep 2019 13:16:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380581; bh=ska6GvcMvDccfwAgcRVlSXG3/h/lqthHXrPwemOftNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MIzPkQHCLewdRK+2DjIRsQHAiji9eBjrlWawdkGgrGx9uS41Rj07/wDx0AeVdcM1X EKJ6/0o31EJNOOhpg/DN1qzK9XxCCx5Zm5ED+n6IoblW+rpvYdwSYR8dirb8tvIydp k2QTlLoGG+ieRP+GpIoS+1DMvuk+4HI9Ah/VcOyI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hans de Goede , Guenter Roeck , Sasha Levin Subject: [PATCH 4.19 110/190] usb: typec: tcpm: Try PD-2.0 if sink does not respond to 3.0 source-caps Date: Fri, 13 Sep 2019 14:06:05 +0100 Message-Id: <20190913130608.527985720@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190913130559.669563815@linuxfoundation.org> References: <20190913130559.669563815@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit 976daf9d1199932df80e7b04546d1a1bd4ed5ece ] PD 2.0 sinks are supposed to accept src-capabilities with a 3.0 header and simply ignore any src PDOs which the sink does not understand such as PPS but some 2.0 sinks instead ignore the entire PD_DATA_SOURCE_CAP message, causing contract negotiation to fail. This commit fixes such sinks not working by re-trying the contract negotiation with PD-2.0 source-caps messages if we don't have a contract after PD_N_HARD_RESET_COUNT hard-reset attempts. The problem fixed by this commit was noticed with a Type-C to VGA dongle. Signed-off-by: Hans de Goede Reviewed-by: Guenter Roeck Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/typec/tcpm.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c index fb20aa974ae12..819ae3b2bd7e8 100644 --- a/drivers/usb/typec/tcpm.c +++ b/drivers/usb/typec/tcpm.c @@ -37,6 +37,7 @@ S(SRC_ATTACHED), \ S(SRC_STARTUP), \ S(SRC_SEND_CAPABILITIES), \ + S(SRC_SEND_CAPABILITIES_TIMEOUT), \ S(SRC_NEGOTIATE_CAPABILITIES), \ S(SRC_TRANSITION_SUPPLY), \ S(SRC_READY), \ @@ -2987,10 +2988,34 @@ static void run_state_machine(struct tcpm_port *port) /* port->hard_reset_count = 0; */ port->caps_count = 0; port->pd_capable = true; - tcpm_set_state_cond(port, hard_reset_state(port), + tcpm_set_state_cond(port, SRC_SEND_CAPABILITIES_TIMEOUT, PD_T_SEND_SOURCE_CAP); } break; + case SRC_SEND_CAPABILITIES_TIMEOUT: + /* + * Error recovery for a PD_DATA_SOURCE_CAP reply timeout. + * + * PD 2.0 sinks are supposed to accept src-capabilities with a + * 3.0 header and simply ignore any src PDOs which the sink does + * not understand such as PPS but some 2.0 sinks instead ignore + * the entire PD_DATA_SOURCE_CAP message, causing contract + * negotiation to fail. + * + * After PD_N_HARD_RESET_COUNT hard-reset attempts, we try + * sending src-capabilities with a lower PD revision to + * make these broken sinks work. + */ + if (port->hard_reset_count < PD_N_HARD_RESET_COUNT) { + tcpm_set_state(port, HARD_RESET_SEND, 0); + } else if (port->negotiated_rev > PD_REV20) { + port->negotiated_rev--; + port->hard_reset_count = 0; + tcpm_set_state(port, SRC_SEND_CAPABILITIES, 0); + } else { + tcpm_set_state(port, hard_reset_state(port), 0); + } + break; case SRC_NEGOTIATE_CAPABILITIES: ret = tcpm_pd_check_request(port); if (ret < 0) { -- 2.20.1