From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="KIGrSUqL" Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DE8F10E9; Tue, 21 Nov 2023 06:15:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1700576160; x=1732112160; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=xQgVwAbHsU1vIB6WJDcMNKCuymgxW0pjQWc+1BIVk7Q=; b=KIGrSUqLXKt2il7mfH+t2PVMaMm0QGfIDPXr/Asg2Zj7JZt+D70j3MtW dJdqAmONs1yHm8WyTq5DkZF4Ssyhxt8FMct4k2X6ZaTZNOOqmlJAOy61F x/AeGogUED+r8cOaGcb/K253KpFHLTt9Fmh6oDUBvBabhfLtfHel+Ga6o erOjh7iwyhC7n0ICBmsgXzhMeP10On3h8CVWcqzRGLcMfjWDFY6Vc3V7A YYuAaWo2pmKmFlJqses/0x1T2aH+2XlCcFHKG1VhbgwlbdVzngQ0Y2M6+ +giIw0qAU5vA8Y6sxSpmGY3dvXvTBMnCjNLDrMPC8bt7rf835jfzOmiI2 A==; X-IronPort-AV: E=McAfee;i="6600,9927,10901"; a="5040917" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="5040917" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Nov 2023 06:15:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10901"; a="832659372" X-IronPort-AV: E=Sophos;i="6.04,215,1695711600"; d="scan'208";a="832659372" Received: from kuha.fi.intel.com ([10.237.72.185]) by fmsmga008.fm.intel.com with SMTP; 21 Nov 2023 06:15:54 -0800 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Tue, 21 Nov 2023 16:15:53 +0200 Date: Tue, 21 Nov 2023 16:15:53 +0200 From: Heikki Krogerus To: Guan-Yu Lin Cc: linux@roeck-us.net, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, badhri@google.com, kyletso@google.com, albertccwang@google.com Subject: Re: [PATCH] usb: typec: tcpm: skip checking port->send_discover in PD3.0 Message-ID: References: <20231116083221.1201892-1-guanyulin@google.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231116083221.1201892-1-guanyulin@google.com> On Thu, Nov 16, 2023 at 04:32:16PM +0800, Guan-Yu Lin wrote: > The original Collison Avoidance mechanism, port->send_discover, avoids > the conflict when port partners start AMS almost the same time. However, > this mechanism is replaced by SINK_TX_OK and SINK_TX_NG. Skip the check > in PD3.0 to avoid the deadlock when source is requesting DR_SWAP where > sink is requesting DISCOVER_IDENTITY. > > Signed-off-by: Guan-Yu Lin Reviewed-by: Heikki Krogerus > --- > drivers/usb/typec/tcpm/tcpm.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c > index 058d5b853b57..ff3c171a3a75 100644 > --- a/drivers/usb/typec/tcpm/tcpm.c > +++ b/drivers/usb/typec/tcpm/tcpm.c > @@ -2847,7 +2847,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2863,7 +2863,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > PD_MSG_CTRL_NOT_SUPP, > NONE_AMS); > } else { > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > @@ -2872,7 +2872,7 @@ static void tcpm_pd_ctrl_request(struct tcpm_port *port, > } > break; > case PD_CTRL_VCONN_SWAP: > - if (port->send_discover) { > + if (port->send_discover && port->negotiated_rev < PD_REV30) { > tcpm_queue_message(port, PD_MSG_CTRL_WAIT); > break; > } > -- > 2.43.0.rc0.421.g78406f8d94-goog -- heikki