From patchwork Sat Mar 17 09:05:32 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 7340 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id 75E1A23E29 for ; Sat, 17 Mar 2012 09:05:45 +0000 (UTC) Received: from mail-iy0-f180.google.com (mail-iy0-f180.google.com [209.85.210.180]) by fiordland.canonical.com (Postfix) with ESMTP id 176FEA183A3 for ; Sat, 17 Mar 2012 09:05:44 +0000 (UTC) Received: by iage36 with SMTP id e36so8800316iag.11 for ; Sat, 17 Mar 2012 02:05:44 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-forwarded-to:x-forwarded-for:delivered-to:received-spf:from:to :subject:date:user-agent:cc:references:in-reply-to:mime-version :content-type:content-transfer-encoding:message-id:x-provags-id :x-gm-message-state; bh=zL4JwbbKOv5PCCycYNSVEFqr/cXTgOKs5/ree30WpXg=; b=DaO27dDbMZOXC0rfzF5shHHGOaKh2vj4BaGhXDMtPZaSNEC1AXUy6kYYPVFNd3NknS F8CZJzAcI1iZmHx7UlvPSAt+IaAIxtMPR7oHekFKyrBZdqWNtDDE4sSMyaY/S0GgMJ96 oGKMS+LRZCoQmdZNqm1QrnOe0vzqSPOF5shGz0F/biTRk1+I12yPtv616qei/9fb6Vne IN7yAiNigH67p1S+XbSY5yhLGfKEy/YKktdtKjIseHDds0sAsqVhV+a31r3MIsp0coWp ICk+L8Fr4IN4dn4eO3FvkHrg3sNrVsuaYa302SD83ccMqO+E2gWMDUXR9WU4/VqbQbLg 1Qsg== Received: by 10.50.159.198 with SMTP id xe6mr1686380igb.74.1331975143298; Sat, 17 Mar 2012 02:05:43 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.231.53.18 with SMTP id k18csp25949ibg; Sat, 17 Mar 2012 02:05:42 -0700 (PDT) Received: by 10.180.89.9 with SMTP id bk9mr4991263wib.11.1331975141462; Sat, 17 Mar 2012 02:05:41 -0700 (PDT) Received: from moutng.kundenserver.de (moutng.kundenserver.de. [212.227.126.186]) by mx.google.com with ESMTP id j9si2378742wia.32.2012.03.17.02.05.40; Sat, 17 Mar 2012 02:05:41 -0700 (PDT) Received-SPF: neutral (google.com: 212.227.126.186 is neither permitted nor denied by best guess record for domain of arnd@arndb.de) client-ip=212.227.126.186; Authentication-Results: mx.google.com; spf=neutral (google.com: 212.227.126.186 is neither permitted nor denied by best guess record for domain of arnd@arndb.de) smtp.mail=arnd@arndb.de Received: from klappe2.localnet (HSI-KBW-46-223-44-216.hsi.kabel-badenwuerttemberg.de [46.223.44.216]) by mrelayeu.kundenserver.de (node=mrbap2) with ESMTP (Nemesis) id 0Lfp8c-1SgXV40rvO-00pa9B; Sat, 17 Mar 2012 10:05:36 +0100 From: Arnd Bergmann To: "Turquette, Mike" Subject: Re: [PATCH v7 1/3] Documentation: common clk API Date: Sat, 17 Mar 2012 09:05:32 +0000 User-Agent: KMail/1.12.2 (Linux/3.3.0-rc1; KDE/4.3.2; x86_64; ; ) Cc: Paul Walmsley , linux-arm-kernel@lists.infradead.org, Amit Kucheria , Nicolas Pitre , linaro-dev@lists.linaro.org, Linus Walleij , Grant Likely , Saravana Kannan , Jeremy Kerr , Magnus Damm , Deepak Saxena , patches@linaro.org, Sascha Hauer , Rob Herring , Russell King , Thomas Gleixner , Richard Zhao , Shawn Guo , Linus Walleij , Mark Brown , Stephen Boyd , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org References: <1331878280-2758-1-git-send-email-mturquette@linaro.org> In-Reply-To: MIME-Version: 1.0 Message-Id: <201203170905.33191.arnd@arndb.de> X-Provags-ID: V02:K0:Re8/0Q/VyVfaZN1kUlRE9ffQ/0tFHXgswrz4RNm+oqN Eq4Uj7PJWB2Nl2LgwMHbr7RUF7/Hke4YCnui2CfG4ONN7Az/XA QOhPRFml8Qm667d/In9pDbNeWi61wOBSgLLya8WloidXpIj3ak ys0/F5t75mK4/cTFD1biETtzOqrvrTIh717PB0bhOyOdIZHILO L+SPLzm9cvT0quHtSpfVJ68CFEu1i58YFNt978ZGp7uBsPLgJc OxyU2WrErXzwaA1uYeFAkH2qvv50EJBm6nBUoduqV148Mir2lo UYX6poQ4QZVI0q8SIMsA+YhRXv75P7f9O0jUy3rYWzUpAXRA0G GvzpmH9ODtQBGFhf1CJE= X-Gm-Message-State: ALoCoQkl1dyCti35nLif0XDcf3hPZN+N8FwiENYWbz1+FXcRhgrKARXV8VqfnJDj84W3dM0nrlgN On Friday 16 March 2012, Turquette, Mike wrote: > On Fri, Mar 16, 2012 at 3:21 PM, Paul Walmsley wrote: > > From: Paul Walmsley > > Date: Fri, 16 Mar 2012 16:06:30 -0600 > > Subject: [PATCH] clk: mark the common clk code as EXPERIMENTAL for now > > > > Mark the common clk code as depending on CONFIG_EXPERIMENTAL. The API > > is not well-defined and both it and the underlying mechanics are likely > > to need significant changes to support non-trivial uses of the rate > > changing code, such as DVFS with external I/O devices. So any platforms > > that switch their implementation over to this may need to revise much > > of their driver code and revalidate their implementations until the > > behavior of the code is better-defined. > > > > A good time for removing this EXPERIMENTAL designation would be after at > > least two platforms that do DVFS on groups of external I/O devices have > > ported their clock implementations over to the common clk code. > > > > Signed-off-by: Paul Walmsley > > Cc: Mike Turquette > > ACK. This will set some reasonable expectations while things are in flux. > > Arnd are you willing to take this in? I think it's rather pointless, because the option is not going to be user selectable but will get selected by the platform unless I'm mistaken. The platform maintainers that care already know the state of the framework. Also, there are no user space interfaces that we have to warn users about not being stable, because the framework is internal to the kernel. However, I wonder whether we need the patch below to prevent users from accidentally enabling COMMON_CLK on platforms that already provide their own implementation. Arnd diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 2eaf17e..a0a83de 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -12,7 +12,7 @@ config HAVE_MACH_CLKDEV menuconfig COMMON_CLK - bool "Common Clock Framework" + bool select HAVE_CLK_PREPARE ---help--- The common clock framework is a single definition of struct clk, useful across many platforms, as well as an