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 A8754C77B7D for ; Sun, 14 May 2023 05:41:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231860AbjENFl0 (ORCPT ); Sun, 14 May 2023 01:41:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229548AbjENFlZ (ORCPT ); Sun, 14 May 2023 01:41:25 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 968C52129; Sat, 13 May 2023 22:41:24 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 634638106; Sun, 14 May 2023 05:41:23 +0000 (UTC) Date: Sun, 14 May 2023 08:41:22 +0300 From: Tony Lindgren To: Greg Kroah-Hartman Cc: Jiri Slaby , Andy Shevchenko , Dhruva Gole , Ilpo =?utf-8?B?SsOkcnZpbmVu?= , Johan Hovold , Sebastian Andrzej Siewior , Vignesh Raghavendra , linux-omap@vger.kernel.org, Andy Shevchenko , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org Subject: Re: [PATCH v11 1/1] serial: core: Start managing serial controllers to enable runtime PM Message-ID: <20230514054122.GH14287@atomide.com> References: <20230511065355.47525-1-tony@atomide.com> <2023051332-pretended-spoiler-61fc@gregkh> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <2023051332-pretended-spoiler-61fc@gregkh> Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org * Greg Kroah-Hartman [230513 11:10]: > On Thu, May 11, 2023 at 09:53:51AM +0300, Tony Lindgren wrote: > > We want to enable runtime PM for serial port device drivers in a generic > > way. To do this, we want to have the serial core layer manage the > > registered physical serial controller devices. > > > > To do this, let's set up a struct bus and struct device for the serial > > core controller as suggested by Greg and Jiri. The serial core controller > > devices are children of the physical serial port device. The serial core > > controller device is needed to support multiple different kind of ports > > connected to single physical serial port device. > > > > Let's also set up a struct device for the serial core port. The serial > > core port instances are children of the serial core controller device. > > > > With the serial core port device we can now flush pending TX on the > > runtime PM resume as suggested by Johan. > > Much better, thanks! > > One thing jumps out at me though, you are passing around "raw" struct > device pointers as the serial port structure, why? > > Shouldn't: > > > @@ -563,7 +564,8 @@ struct uart_port { > > unsigned int minor; > > resource_size_t mapbase; /* for ioremap */ > > resource_size_t mapsize; > > - struct device *dev; /* parent device */ > > + struct device *dev; /* serial port physical parent device */ > > + struct device *port_dev; /* serial core port device */ > > port_dev here be something like "struct serial_port" (or some better > name)? That way you enforce the type being passed around to the serial > code in this change which will help catch any type mistakes. > > Yes, this structure can just be a "wrapper" around 'struct device' but > at least it's a unique type. Good idea thanks, will change. > Or am I missing why this was done this way? No reason to keep it as struct device. Regards, Tony