From patchwork Tue Aug 23 17:09:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rajat Khandelwal X-Patchwork-Id: 12952476 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84032C32772 for ; Tue, 23 Aug 2022 18:46:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233810AbiHWSqg (ORCPT ); Tue, 23 Aug 2022 14:46:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39976 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231714AbiHWSqW (ORCPT ); Tue, 23 Aug 2022 14:46:22 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 942C4B2D9F; Tue, 23 Aug 2022 10:09:57 -0700 (PDT) X-IronPort-AV: E=McAfee;i="6500,9779,10448"; a="292491145" X-IronPort-AV: E=Sophos;i="5.93,258,1654585200"; d="scan'208";a="292491145" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Aug 2022 10:09:57 -0700 X-IronPort-AV: E=Sophos;i="5.93,258,1654585200"; d="scan'208";a="670121475" Received: from unknown (HELO rajath-NUC10i7FNH..) ([10.223.165.55]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Aug 2022 10:09:55 -0700 From: Rajat Khandelwal To: heikki.krogerus@linux.intel.com, gregkh@linuxfoundation.org Cc: rajat.khandelwal@intel.com, shawn.c.lee@intel.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] Enter safe mode only when pins need to be reconfigured Date: Tue, 23 Aug 2022 22:39:49 +0530 Message-Id: <20220823170949.2066916-1-rajat.khandelwal@intel.corp-partner.google.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: Lee Shawn C There is no point to enter safe mode during DP/TBT configuration if the DP/TBT was already configured in mux. This is because safe mode is only applicable when there is a need to reconfigure the pins in order to avoid damage within/to port partner. 1. if HPD interrupt arrives and DP mode was already configured, safe mode is entered again which is not desired. 2. in chrome systems, IOM/mux is already configured before OS comes up. Thus, when driver is probed, it blindly enters safe mode due to PD negotiations but only after gfx driver lowers dp_phy_ownership, will the IOM complete safe mode and send ack to PMC. Since, that never happens, we see IPC timeout. Hence, allow safe mode only when pin reconfiguration is not required, which makes sense. Signed-off-by: Rajat Khandelwal Signed-off-by: Lee Shawn C --- drivers/usb/typec/mux/intel_pmc_mux.c | 26 +++++++++++++++++++++++++- 1 file changed, 25 insertions(+), 1 deletion(-) diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c index d238913e996a..4bf84466d1ff 100644 --- a/drivers/usb/typec/mux/intel_pmc_mux.c +++ b/drivers/usb/typec/mux/intel_pmc_mux.c @@ -432,6 +432,25 @@ static int pmc_usb_connect(struct pmc_usb_port *port, enum usb_role role) return pmc_usb_command(port, msg, sizeof(msg)); } +static bool +pmc_usb_mux_allow_to_enter_safe_mode(struct pmc_usb_port *port, + struct typec_mux_state *state) +{ + if ((IOM_PORT_ACTIVITY_IS(port->iom_status, DP) || + IOM_PORT_ACTIVITY_IS(port->iom_status, DP_MFD)) && + state->alt && + state->alt->svid == USB_TYPEC_DP_SID) + return false; + + if ((IOM_PORT_ACTIVITY_IS(port->iom_status, TBT) || + IOM_PORT_ACTIVITY_IS(port->iom_status, ALT_MODE_TBT_USB)) && + state->alt && + state->alt->svid == USB_TYPEC_TBT_SID) + return false; + + return true; +} + static int pmc_usb_mux_set(struct typec_mux *mux, struct typec_mux_state *state) { @@ -442,8 +461,13 @@ pmc_usb_mux_set(struct typec_mux *mux, struct typec_mux_state *state) if (port->orientation == TYPEC_ORIENTATION_NONE || port->role == USB_ROLE_NONE) return 0; - if (state->mode == TYPEC_STATE_SAFE) + if (state->mode == TYPEC_STATE_SAFE) { + if (!pmc_usb_mux_allow_to_enter_safe_mode(port, state)) + return 0; + return pmc_usb_mux_safe_state(port); + } + if (state->mode == TYPEC_STATE_USB) return pmc_usb_connect(port, port->role);