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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 908C8C3A5A2 for ; Tue, 3 Sep 2019 16:27:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 66CFB238F9 for ; Tue, 3 Sep 2019 16:27:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567528079; bh=Jx4h1OLqgtM+TERApXP4s/2ms0EySlgEHJea4wI2Qf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=vmh4HzOTXxNgwj5MDxB/CH+3Dg4aZHKqRqJmpeg1RgFCAGHXbX//2m4fqeuHAR5i3 OpVusyzGTfD13DcOALyA71v6cN8uAHtBvLPD/nr3x48YW6m9iRdRkX7xJLavpq+dH1 +4nqnsfWIVZHExHk12UtcfLZNBl88/sD85xTra9c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730998AbfICQ16 (ORCPT ); Tue, 3 Sep 2019 12:27:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:49562 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730986AbfICQ15 (ORCPT ); Tue, 3 Sep 2019 12:27:57 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 98772238C5; Tue, 3 Sep 2019 16:27:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567528076; bh=Jx4h1OLqgtM+TERApXP4s/2ms0EySlgEHJea4wI2Qf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DH7yIoGwDMBTdYv3qFeQSRvtY6GlzdhCxWqSgXJkLrP2DfIg7UOCxa4i1de3YteXg WcuQj56idzDoSJ1zcLdkuf2TIW4dob1UErDoo/PyCrrNuwMyIHTUw3yGKPZvG0GEwB zqIcSldOknaaGI+tu1ZWQxM2e9SDdpqwtqZPuQdo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hans de Goede , Guenter Roeck , Greg Kroah-Hartman , Sasha Levin , linux-usb@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 089/167] usb: typec: tcpm: Try PD-2.0 if sink does not respond to 3.0 source-caps Date: Tue, 3 Sep 2019 12:24:01 -0400 Message-Id: <20190903162519.7136-89-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190903162519.7136-1-sashal@kernel.org> References: <20190903162519.7136-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: Hans de Goede [ 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 5f29ce8d6c3f9..e8524ad5a4c0a 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