Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752793Ab3GQH6c (ORCPT ); Wed, 17 Jul 2013 03:58:32 -0400 Received: from mail-ob0-f178.google.com ([209.85.214.178]:58986 "EHLO mail-ob0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752650Ab3GQH6a (ORCPT ); Wed, 17 Jul 2013 03:58:30 -0400 MIME-Version: 1.0 In-Reply-To: <6633375.dICiDrHJgK@vostro.rjw.lan> References: <1370502472-7249-1-git-send-email-l.majewski@samsung.com> <51C1EF05.90402@gmail.com> <20130619223102.70c2e359@jawa> <6633375.dICiDrHJgK@vostro.rjw.lan> Date: Wed, 17 Jul 2013 13:28:29 +0530 Message-ID: Subject: Re: [PATCH v4 2/7] cpufreq: Add boost frequency support in core From: Viresh Kumar To: Lukasz Majewski , Dirk Brandewie , "Rafael J. Wysocki" Cc: Lukasz Majewski , "cpufreq@vger.kernel.org" , Linux PM list , Vincent Guittot , Jonghwa Lee , Myungjoo Ham , linux-kernel , Andre Przywara , Daniel Lezcano , Kukjin Kim , Zhang Rui , Eduardo Valentin Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1917 Lines: 55 On 20 June 2013 03:55, Rafael J. Wysocki wrote: > On Wednesday, June 19, 2013 10:31:02 PM Lukasz Majewski wrote: >> On Wed, 19 Jun 2013 10:48:53 -0700 >> Dirk Brandewie wrote: >> >> > On 06/19/2013 10:12 AM, Lukasz Majewski wrote: >> > > @@ -1936,6 +2019,16 @@ int cpufreq_register_driver(struct >> > > + if (!cpufreq_driver->boost_supported) >> > > + boost.attr.mode = 0444; >> > > + >> > > + ret = cpufreq_sysfs_create_file(&(boost.attr)); >> > > + if (ret) { >> > > + pr_err("%s: cannot register global boost sysfs >> > > file\n", >> > > + __func__); >> > > + goto err_null_driver; >> > > + } >> > > + >> > >> > I do not think the boost sysfs should be created at all if boost is >> > not supported. >> >> This was my first thought. But unfortunately this "boost" attribute is >> always exported at acpi-cpufreq.c and in my opinion is part of a >> legacy API. >> >> I totally agree with the idea of exporting boost only when supported, >> but I would like to know the community opinion about this (especially >> Viresh and Rafael shall speak up). > > Simple: Export it only when supported. Guys, I got confused here. We originally decided to keep this feature as is for acpi-cpufreq. So, For acpi-cpufreq: - when boost isn't supported: create sysfs boost with ro permissions - when boost is supported: create sysfs boost with rw permissions So, For others: - create sysfs boost with rw permissions only when boost is supported . Do you want something else? or do you want to change behavior of acpi-cpufreq driver? I don't why it was designed this way and what applications use it. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/