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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 3E735C2B9F8 for ; Tue, 25 May 2021 00:12:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B612613F5 for ; Tue, 25 May 2021 00:12:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229875AbhEYAO0 (ORCPT ); Mon, 24 May 2021 20:14:26 -0400 Received: from new4-smtp.messagingengine.com ([66.111.4.230]:39317 "EHLO new4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229543AbhEYAOZ (ORCPT ); Mon, 24 May 2021 20:14:25 -0400 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailnew.nyi.internal (Postfix) with ESMTP id 241CA58094E; Mon, 24 May 2021 20:12:56 -0400 (EDT) Received: from imap2 ([10.202.2.52]) by compute3.internal (MEProxy); Mon, 24 May 2021 20:12:56 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aj.id.au; h= mime-version:message-id:in-reply-to:references:date:from:to:cc :subject:content-type; s=fm2; bh=d2zEUntdeXJWYmAyxI56N4QgHdNvMV1 cDqrmFJTjfjI=; b=OqoVhqH34YPXVFKBrbOk5IpHlbe7l5x4hc+UB7WirS4hk1Y uECLjyU3QdbrJ/w9qRZpAMMyiX6qFeBkMj3Zvteq9Emp6smH/4EQgimOSOjtQOL1 CFH5gfBnflZgn+nCi4lhhgX/8gBA8jUII+O477YbmKiYUkhhLRGz0m0wzZ1qkepo DvyqDPIB7Rmk4eS7VdOvnnxiioIkfX1rrVaEYxy+/531D1+BqnMqCWM/Q2LHQIRq Y9lhN5XwuBYTXYiWo/POsT233pRHtITR0BxZV3EaYJjxod2sM3b8p1ZrCHiHFQwy LuWDJ3cY3QtifTayq8YiT/nyxREB2C3UWdGk28A== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=d2zEUn tdeXJWYmAyxI56N4QgHdNvMV1cDqrmFJTjfjI=; b=LTO/qW8Bh92w5dNv4wEW7I yfnmJcWmUK7o4xwKs2OjWsPssTZwlyXKJsqMrXfqaVRdz2JQKWK8CEyFZwrZMixE pSjQqduFdiKSEHOGGo8Mqz5J6kEyUr8/mEnup4O3/BAO5lJM3jz81LR65BWti0di f5u57AXxwdk2J/Vtiqxb1E5RhtJR085o4RXyxxcjcF/0tQwyYtelPJLhkj287PA5 OF+b90rF+KdMoty+nKCrnUTaoBAVG+EvEHxZhg2e6LkT03JR0+tKsdZv8aCOoehn W0eT5UbJWJXNOEf8Z4pr2XULBLz18vORHBlTRsMQS4gB1ikVCGEOA8iq9D+c6LiA == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledrvdektddgvdelucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvffutgesthdtredtreerjeenucfhrhhomhepfdetnhgu rhgvficulfgvfhhfvghrhidfuceorghnughrvgifsegrjhdrihgurdgruheqnecuggftrf grthhtvghrnhepuddttdekueeggedvtddtueekiedutdfguedutdefieeuteefieelteet vddthfeinecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomh eprghnughrvgifsegrjhdrihgurdgruh X-ME-Proxy: Received: by mailuser.nyi.internal (Postfix, from userid 501) id ACC11A00079; Mon, 24 May 2021 20:12:54 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.5.0-alpha0-448-gae190416c7-fm-20210505.004-gae190416 Mime-Version: 1.0 Message-Id: <9a290af6-522f-4055-bd26-e5818cc97bcb@www.fastmail.com> In-Reply-To: <20210524154119.GN2921206@minyard.net> References: <20210510054213.1610760-1-andrew@aj.id.au> <20210510054213.1610760-6-andrew@aj.id.au> <20210521171412.GI2921206@minyard.net> <79f3c6d1-1f74-46ec-99a0-37faf11517b6@www.fastmail.com> <20210524154119.GN2921206@minyard.net> Date: Tue, 25 May 2021 09:42:34 +0930 From: "Andrew Jeffery" To: "Corey Minyard" Cc: devicetree@vger.kernel.org, "Tomer Maimon" , linux-aspeed@lists.ozlabs.org, "Avi Fishman" , "Patrick Venture" , openbmc@lists.ozlabs.org, linux-kernel@vger.kernel.org, "Tali Perry" , "Rob Herring" , "Arnd Bergmann" , openipmi-developer@lists.sourceforge.net, "Zev Weiss" , "Chia-Wei, Wang" , linux-arm-kernel@lists.infradead.org, "Benjamin Fair" Subject: =?UTF-8?Q?Re:_[Openipmi-developer]_[PATCH_v3_05/16]_ipmi:_kcs=5Fbmc:_Tur?= =?UTF-8?Q?n_the_driver_data-structures_inside-out?= Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 25 May 2021, at 01:11, Corey Minyard wrote: > On Mon, May 24, 2021 at 10:23:36AM +0930, Andrew Jeffery wrote: > > > > > > On Sat, 22 May 2021, at 02:44, Corey Minyard wrote: > > > On Mon, May 10, 2021 at 03:12:02PM +0930, Andrew Jeffery wrote: > > > > Make the KCS device drivers responsible for allocating their own memory. > > > > > > > > Until now the private data for the device driver was allocated internal > > > > to the private data for the chardev interface. This coupling required > > > > the slightly awkward API of passing through the struct size for the > > > > driver private data to the chardev constructor, and then retrieving a > > > > pointer to the driver private data from the allocated chardev memory. > > > > > > > > In addition to being awkward, the arrangement prevents the > > > > implementation of alternative userspace interfaces as the device driver > > > > private data is not independent. > > > > > > > > Peel a layer off the onion and turn the data-structures inside out by > > > > exploiting container_of() and embedding `struct kcs_device` in the > > > > driver private data. > > > > > > All in all a very nice cleanup. A few nits inline. > > > > > > > > > > > Signed-off-by: Andrew Jeffery > > > > Reviewed-by: Zev Weiss > > > > --- > > > > drivers/char/ipmi/kcs_bmc.c | 19 +++++++-- > > > > drivers/char/ipmi/kcs_bmc.h | 12 ++---- > > > > drivers/char/ipmi/kcs_bmc_aspeed.c | 56 +++++++++++++------------ > > > > drivers/char/ipmi/kcs_bmc_cdev_ipmi.c | 60 ++++++++++++++++++--------- > > > > drivers/char/ipmi/kcs_bmc_npcm7xx.c | 37 ++++++++++------- > > > > 5 files changed, 111 insertions(+), 73 deletions(-) > > > > > > > > diff --git a/drivers/char/ipmi/kcs_bmc.c b/drivers/char/ipmi/kcs_bmc.c > > > > index ef5c48ffe74a..83da681bf49e 100644 > > > > --- a/drivers/char/ipmi/kcs_bmc.c > > > > +++ b/drivers/char/ipmi/kcs_bmc.c > > > > @@ -44,12 +44,23 @@ int kcs_bmc_handle_event(struct kcs_bmc *kcs_bmc) > > > > } > > > > EXPORT_SYMBOL(kcs_bmc_handle_event); > > > > > > > > -struct kcs_bmc *kcs_bmc_ipmi_alloc(struct device *dev, int sizeof_priv, u32 channel); > > > > -struct kcs_bmc *kcs_bmc_alloc(struct device *dev, int sizeof_priv, u32 channel) > > > > +int kcs_bmc_ipmi_add_device(struct kcs_bmc *kcs_bmc); > > > > > > The above (and it's remove function) should be in an include file. > > > > This is a short-term hack while I'm refactoring the code. It goes away > > in a later patch when we switch to using an ops struct. > > > > I didn't move it to a header as it's an implementation detail at the > > end of the day. I see headers as describing a public interface, and in > > the bigger picture this function isn't part of the public API. But > > maybe it's too tricky by half. My approach here generated some > > discussion with Zev as well. > > > > > > > > > +void kcs_bmc_add_device(struct kcs_bmc *kcs_bmc) > > > > > > This should return an error so the probe can be failed and cleaned up > > > and so confusing message don't get printed after this in one case. > > > > Hmm. I did this because the end result of the series is that we can > > have multiple chardev interfaces in distinct modules exposing the one > > KCS device in the one kernel. If more than one of the chardev modules > > is configured in and one of them fails to initialise themselves with > > respect to the device driver I didn't think it was right to fail the > > probe of the device driver (and thus remove any chardev interfaces that > > did succeed to initialise against it). > > > > But this does limit the usefulness of the device driver instance in the > > case that only one of the chardev interfaces is configured in and it > > fails to initialise. > > > > So I think we need to decide on the direction before I adjust the > > interface here. The patches are architected around the idea of multiple > > chardevs being configured in to the kernel build and all are exposed at > > runtime. > > Ok, I understand. The host IPMI driver will attempt to start all > interfaces, if none fail to come up it will return an error, but if any > come up it will not return an error. So it's a similar situation. That sounds reasonable. I'll implement this strategy. > > I stole that from something else, but I can't remember what. I don't > know what the best policy is, really, that was kind of a compromise and > nobody has complained about it. > > I will say that the success print in aspeed_kcs_probe() needs to not > happen if there is a failure, though. With the strategy you outlined above that's easy enough. Thanks, Andrew