From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753498AbdJMGr3 (ORCPT ); Fri, 13 Oct 2017 02:47:29 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:13631 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751414AbdJMGr1 (ORCPT ); Fri, 13 Oct 2017 02:47:27 -0400 X-AuditID: b6c32a47-499ff70000001114-c2-59e0617c858d MIME-version: 1.0 Content-transfer-encoding: 8BIT Content-type: text/plain; charset="utf-8" Message-id: <59E0617D.10309@samsung.com> Date: Fri, 13 Oct 2017 15:47:25 +0900 From: Chanwoo Choi Organization: Samsung Electronics User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 To: "myungjoo.ham@samsung.com" Cc: cwchoi00@gmail.com, Kyungmin Park , "rafael.j.wysocki@intel.com" , Inki Dae , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" Subject: Re: [PATCH v3 3/8] PM / devfreq: Show the available min/max frequency through sysfs node In-reply-to: <59DEEAA5.3050905@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrBKsWRmVeSWpSXmKPExsWy7bCmhW5N4oNIg3m7DC2eHdW2mHR/AovF 2aY37BaXd81hs/jce4TR4nbjCjaLxyvesjuwe+ycdZfdY/Gel0wefVtWMXp83iQXwBKVapOR mpiSWqSQmpecn5KZl26r5B0c7xxvamZgqGtoaWGupJCXmJtqq+TiE6DrlpkDdICSQlliTilQ KCCxuFhJ386mKL+0JFUhI7+4xFYp2tDQSM/QwFzPyMhIz8Q41srIFKgkITVj4oOXjAXvpCsu njzA2MDYJtbFyMkhIWAiMf/OBcYuRi4OIYEdjBKPm65COd8ZJV7Pn8AMU7Xy+z12iMQGRokz 2y4zgSR4BQQlfky+x9LFyMHBLCAvceRSNkiYWUBT4sWXSSwQ9fcYJSb1vGaBqNeQ+PtmCiuI zSKgKjGvowFsDpuAlsT+FzfYQGx+AUWJqz8eM4LYogIREjvnf2MHsUUELCWWzZrEDDKUWWA2 k8T71ulgQ4UFkiUmtX0HszkFtCW+fb7KClIkIXCCTWJTczsjxAsuEqc/3YSyhSVeHd/CDmFL SzxbtZERoqGdUWLznHssEE4Ho8T9lY2sEFXGEqe6GpkgnuOT6Dj8lx3kZwkBXomONiGIEg+J mVtms0DYjhKty5ZB/f+ZSaJpyU/GCYxys5CCbBYiyGYhBdkCRuZVjGKpBcW56anFRgXGesWJ ucWleel6yfm5mxjBqU7LfQfjtnM+hxgFOBiVeHgFqu5HCrEmlhVX5h5ilOBgVhLhVXV9ECnE m5JYWZValB9fVJqTWnyI0RQY4hOZpUST84FpOK8k3tDE0sDEzMzI3MwCmMbEeeu2XYsQEkhP LEnNTk0tSC2C6WPi4JRqYPRrSAuecTmh+4795edFUrmvpt/w1DhU+YKtt5Lfr/7W4Y9BkvVG OwqW2r47smn1U0M9D49GkdWPBWRfZRdskou6P+c8/9qLctYZL5eeMdrzoGab66THn09WKOy9 e+zOdDX//w1seWypn2cs3/6uXvLzoserow48VNm9j5nhx89+vvBqrzDtsK9KLMUZiYZazEXF iQAcItq/iwMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrOLMWRmVeSWpSXmKPExsVy+t9jQd2axAeRBgvX81s8O6ptMen+BBaL s01v2C0u75rDZvG59wijxe3GFWwWj1e8ZXdg99g56y67x+I9L5k8+rasYvT4vEkugCWKyyYl NSezLLVI3y6BK2Pig5eMBe+kKy6ePMDYwNgm1sXIySEhYCKx8vs99i5GLg4hgXWMEtM33mYB SfAKCEr8mHwPyObgYBaQlzhyKRvCVJeYMiUXovwBo8TKd9eZIMo1JP6+mcIKYrMIqErM62gA i7MJaEnsf3GDDcTmF1CUuPrjMSPIHFGBCInuE5UgYREBS4llsyYxg8xkFpjNJPH75gVGkISw QLLEnC9XWCGWfWaSmN50nBkkwSmgLfHt81XWCYwCs5CcOgvh1FkIpy5gZF7FKJlaUJybnlts VGCUl1quV5yYW1yal66XnJ+7iREY3NsOa/XvYHy8JP4QowAHoxIP747y+5FCrIllxZW5hxgl OJiVRHhVXR9ECvGmJFZWpRblxxeV5qQWH2KU5mBREuflzz8WKSSQnliSmp2aWpBaBJNl4uCU amC0r/11wd1gZxJ3pfv9GTklHGqpT5ZwyM48laWnWnxZc2nOi7n/1ssX9MUtybnq9MBNtW9b pdjdy7b59460HYz+xfNJSmfS0a49b63cKrrvJ12YsI/xWfRr+VBh4U//DS3cVxevTN36+dKc G3HCJum+DnVzPOe6L29eVHxXKsk5ax2L0Jyme0JKLMUZiYZazEXFiQD/cfkKagIAAA== X-CMS-MailID: 20171013064724epcas2p3353843552d61983d74063bfc168e46f1 X-Msg-Generator: CA X-Sender-IP: 182.195.42.143 X-Local-Sender: =?UTF-8?B?7LWc7LCs7JqwG1RpemVuIFBsYXRmb3JtIExhYihTL1fshLw=?= =?UTF-8?B?7YSwKRvsgrzshLHsoITsnpAbU2VuaW9yIEVuZ2luZWVy?= X-Global-Sender: =?UTF-8?B?Q2hhbndvbyBDaG9pG1RpemVuIFBsYXRmb3JtIExhYi4bU2Ft?= =?UTF-8?B?c3VuZyBFbGVjdHJvbmljcxtTZW5pb3IgRW5naW5lZXI=?= X-Sender-Code: =?UTF-8?B?QzEwG1RFTEUbQzEwVjgxMTE=?= CMS-TYPE: 102P DLP-Filter: Pass X-CFilter-Loop: Reflected X-CMS-RootMailID: 20171011030946epcas1p40f32955da5dada46e95302701a0afb7d X-RootMTR: 20171011030946epcas1p40f32955da5dada46e95302701a0afb7d References: <1507691364-3899-1-git-send-email-cw00.choi@samsung.com> <1507691364-3899-4-git-send-email-cw00.choi@samsung.com> <20171011111532epcms1p3036bcc7be2cc00057fe478fc868ba71d@epcms1p3> <59DEEAA5.3050905@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 2017년 10월 12일 13:08, Chanwoo Choi wrote: > On 2017년 10월 11일 21:57, Chanwoo Choi wrote: >> On Wed, Oct 11, 2017 at 8:15 PM, MyungJoo Ham wrote: >>>> The existing {min|max}_freq sysfs nodes don't consider whether min/max_freq >>>> are available or not. Those sysfs nodes show just the stored value >>>> in the struct devfreq. >>>> >>>> The devfreq uses the OPP interface and then dev_pm_opp_{disable|add}() >>>> might change the state of the device's supported frequency. This patch >>>> shows the available minimum and maximum frequency through sysfs node. >>>> >>>> Signed-off-by: Chanwoo Choi >>>> --- >>>> drivers/devfreq/devfreq.c | 18 ++++++++++++++++-- >>>> 1 file changed, 16 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c >>>> index 2ce1fd0a1324..799a0cf75d39 100644 >>>> --- a/drivers/devfreq/devfreq.c >>>> +++ b/drivers/devfreq/devfreq.c >>>> @@ -1128,7 +1128,14 @@ static ssize_t min_freq_store(struct device *dev, struct device_attribute *attr, >>>> static ssize_t min_freq_show(struct device *dev, struct device_attribute *attr, >>>> char *buf) >>>> { >>>> - return sprintf(buf, "%lu\n", to_devfreq(dev)->min_freq); >>>> + struct devfreq *df = to_devfreq(dev); >>>> + unsigned long min_freq = to_devfreq(dev)->min_freq; >>>> + unsigned long available_min_freq = find_available_min_freq(df); >>>> + >>>> + if (available_min_freq != 0 && min_freq < available_min_freq) >>> >>> nitpick: >>> >>> If available_min_freq == 0, >>> it can't be min_freq < available_min_freq anyway; >>> it's unsigned. >> >> If the dev_pm_opp_find_*() return the error in the find_available_min_freq(), >> avaiable_min_freq is zero. So, if available_min_freq is zero, >> min_freq_show doesn't need to compare 'min_freq < available_min_freq'. >> >> In result, if 'available_min_freq' is zero, min_freq_show() only considers >> the 'min_freq' variable. > > I'll modify this patch as following: How about that? > > + if (available_min_freq == 0) > + goto out; > + else if (min_freq < available_min_freq) > + min_freq = available_min_freq; > + > +out: > + return sprintf(buf, "%lu\n", min_freq); > Please ignore this approach because I'll use the new 'scaling_min/max_freq' variables on v4. > >>> >>>> + min_freq = available_min_freq; >>>> + >>>> + return sprintf(buf, "%lu\n", min_freq); >>>> } >>>> >>>> static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, >>>> @@ -1162,7 +1169,14 @@ static ssize_t max_freq_store(struct device *dev, struct device_attribute *attr, >>>> static ssize_t max_freq_show(struct device *dev, struct device_attribute *attr, >>>> char *buf) >>>> { >>>> - return sprintf(buf, "%lu\n", to_devfreq(dev)->max_freq); >>>> + struct devfreq *df = to_devfreq(dev); >>>> + unsigned long max_freq = to_devfreq(dev)->max_freq; >>>> + unsigned long available_max_freq = find_available_max_freq(df); >>>> + >>>> + if (available_max_freq != 0 && max_freq > available_max_freq) >>>> + max_freq = available_max_freq; >>> >>> similar here. >> >> ditto. >> >>> >>>> + >>>> + return sprintf(buf, "%lu\n", max_freq); >>>> } >>>> static DEVICE_ATTR_RW(max_freq); >> >> > > -- Best Regards, Chanwoo Choi Samsung Electronics