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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A6B1C433F5 for ; Fri, 1 Apr 2022 13:53:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346546AbiDANz2 (ORCPT ); Fri, 1 Apr 2022 09:55:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345150AbiDANzZ (ORCPT ); Fri, 1 Apr 2022 09:55:25 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3624D3153D; Fri, 1 Apr 2022 06:53:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1648821215; x=1680357215; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=9JVIFR1RY3e4c1DpSi0zz4R7HTop2QK2Mx5IigfiEgA=; b=BgVXgZca8UcIkIqGCH9ubUE6Ty0rdYiMjBpJWb7Eg/7GuzCahVuBdIId /NpljIlBNYOCZrkTKRebmU9vSJTVEGzXJyPpIGG/PxxLZJN4Kq1gkManL WsaDgvkvtzVjsGcT3ca3POO7s6SyUUS5/9728kEWjhF1s323w7EJoPrxn H1dgxiRWnBgfEUk286+5JptMfcjGCje12LFV6pqACxEpUKs6WEuZBpk8W ZPZRZuMWaevQ8iUajE+dUNW8x7AXzNOs5Od+NDurZLOYJzv6qB47LOOmm 3BpsfKhLgXq+LxpQfsWsW1Bzc5lASnwqX/5PYIWXAy++HlkzsRekcqYi3 A==; X-IronPort-AV: E=McAfee;i="6200,9189,10304"; a="323311000" X-IronPort-AV: E=Sophos;i="5.90,227,1643702400"; d="scan'208";a="323311000" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2022 06:53:34 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,227,1643702400"; d="scan'208";a="695898668" Received: from kuha.fi.intel.com ([10.237.72.185]) by fmsmga001.fm.intel.com with SMTP; 01 Apr 2022 06:53:32 -0700 Received: by kuha.fi.intel.com (sSMTP sendmail emulation); Fri, 01 Apr 2022 16:53:31 +0300 Date: Fri, 1 Apr 2022 16:53:31 +0300 From: Heikki Krogerus To: tanveer1.alam@intel.com Cc: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, abhijeet.rao@intel.com Subject: Re: [PATCH] usb: typec: mux: intel_pmc_mux: Add retry logic to a PMC command Message-ID: References: <20220328105137.6223-1-tanveer1.alam@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220328105137.6223-1-tanveer1.alam@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Mar 28, 2022 at 04:21:37PM +0530, tanveer1.alam@intel.com wrote: > From: Tanveer Alam > > There are few scenerio when PMC reports 'busy condition' and command > fail. > > If PMC receives a high priority command while servicing a low priority > command then it discards the low priority command and start servicing > the high priority command. The lower priority command fail and driver > returns error. If the same command resend to the PMC then PMC latches > the command and service it accordingly. > > Thus adds the retry logic for the PMC command. > > Signed-off-by: Tanveer Alam Reviewed-by: Heikki Krogerus > --- > drivers/usb/typec/mux/intel_pmc_mux.c | 21 +++++++++++++++++++-- > 1 file changed, 19 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/typec/mux/intel_pmc_mux.c b/drivers/usb/typec/mux/intel_pmc_mux.c > index 2cdd22130834..da6b381ddf00 100644 > --- a/drivers/usb/typec/mux/intel_pmc_mux.c > +++ b/drivers/usb/typec/mux/intel_pmc_mux.c > @@ -173,7 +173,7 @@ static int hsl_orientation(struct pmc_usb_port *port) > return port->orientation - 1; > } > > -static int pmc_usb_command(struct pmc_usb_port *port, u8 *msg, u32 len) > +static int pmc_usb_send_command(struct intel_scu_ipc_dev *ipc, u8 *msg, u32 len) > { > u8 response[4]; > u8 status_res; > @@ -184,7 +184,7 @@ static int pmc_usb_command(struct pmc_usb_port *port, u8 *msg, u32 len) > * Status can be checked from the response message if the > * function intel_scu_ipc_dev_command succeeds. > */ > - ret = intel_scu_ipc_dev_command(port->pmc->ipc, PMC_USBC_CMD, 0, msg, > + ret = intel_scu_ipc_dev_command(ipc, PMC_USBC_CMD, 0, msg, > len, response, sizeof(response)); > > if (ret) > @@ -203,6 +203,23 @@ static int pmc_usb_command(struct pmc_usb_port *port, u8 *msg, u32 len) > return 0; > } > > +static int pmc_usb_command(struct pmc_usb_port *port, u8 *msg, u32 len) > +{ > + int retry_count = 3; > + int ret; > + > + /* > + * If PMC is busy then retry the command once again > + */ > + while (retry_count--) { > + ret = pmc_usb_send_command(port->pmc->ipc, msg, len); > + if (ret != -EBUSY) > + break; > + } > + > + return ret; > +} > + > static int > pmc_usb_mux_dp_hpd(struct pmc_usb_port *port, struct typec_displayport_data *dp) > { thanks, -- heikki