From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrzej Hajda Subject: Re: [RFC 04/15] regulator: add restrack support Date: Thu, 11 Dec 2014 11:49:54 +0100 Message-ID: <548976D2.7080005@samsung.com> References: <1418226513-14105-1-git-send-email-a.hajda@samsung.com> <1418226513-14105-5-git-send-email-a.hajda@samsung.com> <20141210160720.GS11764@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-reply-to: <20141210160720.GS11764@sirena.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Mark Brown Cc: Alexandre Courbot , "moderated list:ARM/S5P EXYNOS AR..." , Mike Turquette , Liam Girdwood , Greg Kroah-Hartman , open list , Rob Herring , Kishon Vijay Abraham I , "open list:GPIO SUBSYSTEM" , "open list:OPEN FIRMWARE AND..." , "open list:DRM PANEL DRIVERS" , Grant Likely , Russell King , "moderated list:ARM/CLKDEV SUPPORT" , Marek Szyprowski List-Id: linux-gpio@vger.kernel.org SGkgTWFyaywKCk9uIDEyLzEwLzIwMTQgMDU6MDcgUE0sIE1hcmsgQnJvd24gd3JvdGU6Cj4gT24g V2VkLCBEZWMgMTAsIDIwMTQgYXQgMDQ6NDg6MjJQTSArMDEwMCwgQW5kcnplaiBIYWpkYSB3cm90 ZToKPj4gUmVndWxhdG9ycyBzdXBwb3J0cyB2YXJpb3VzIG1ldGhvZHMgb2YgbG9va3VwLgo+PiBU aGUgcGF0Y2ggYWRkcyByZXN0cmFjayBzdXBwb3J0IG9ubHkgdG8gRFQgYmFzZWQgcmVndWxhdG9y cy4KPiBXaHksIHdoYXQgZG9lcyB0aGlzIG1lYW4gYW5kIGhvdyBtaWdodCBvbmUgdXNlIGl0PyAg SSd2ZSBub3QgbG9va2VkIGF0Cj4gdGhlIGNvZGUgc2luY2UgSSBkb24ndCBrbm93IHdoYXQgaXQn cyBzdXBwb3NlZCB0byBhY2NvbXBsaXNoLi4uCgpMb29raW5nIGF0IHRoaXMgcGF0Y2ggbWFrZXMg bm8gc2Vuc2Ugd2l0aG91dCBsb29raW5nIGF0IGNvdmVyIGxldHRlcgpvciBhdCB0aGUgcGF0Y2gg YWRkaW5nIHJlc3RyYWNrIGZyYW1ld29yay4gSW4gc2hvcnQgYWRkaW5nIHJlc3RyYWNrIHN1cHBv cnQKdG8gcmVndWxhdG9ycyB3aWxsIGFsbG93IHRvOgotIHByb3BlciBoYW5kbGUgcmVndWxhdG9y IHByb3ZpZGVyIHVuYmluZC9yZS1iaW5kLCBjdXJyZW50bHkgaXQgcmVzdWx0cwppbiBvb3BzZXMs IGNyYXNoZXMgYW5kIGhhbmdzLAotIGF2b2lkIGxhdGUgcHJvYmUgZHVlIHRvIGRlZmVycmVkIHBy b2JpbmcsIGN1cnJlbnRseSBpZiBwcm9iZSBpcwpkZWZlcnJlZCwgcmUtcHJvYmUgb2NjdXJzIGlu IGxhdGUgaW5pdGNhbGwsCi0gdHJhY2sgYXBwZWFyYW5jZSBvZiByZXNvdXJjZXMgd2hpY2ggY2Fu IGFsdGVyIGJlaGF2aW9yIG9mIHRoZSBkcml2ZXIKaWYgcHJlc2VudCBidXQgdGhleSBhcmUgbm90 IHJlcXVpcmVkLAogIEkgYW0gbm90IHN1cmUgaWYgdGhlcmUgYXJlIHVzZSBjYXNlcyBmb3IgaXQg aW4gY2FzZSBvZiByZWd1bGF0b3JzLCBidXQKb3RoZXIgcmVzb3VyY2VzIGhhdmUgc3VjaCB1c2Ug Y2FzZXMsCi0gYXMgYSBib251cyB3ZSBjYW4gaGF2ZSBzaW1wbGVyIGFsbG9jYXRpb24gb2YgdmFy aW91cyByZXNvdXJjZXMsIHBsZWFzZQpsb29rIGF0IGNvdmVyIGxldHRlciBmb3IgZXhhbXBsZS4K Cj4KPiBPbmUgdmVyeSBoaWdoIGxldmVsIHRoaW5nIGlzIHRoYXQgYW55dGhpbmcgdGhhdCBvbmx5 IHdvcmtzIGZvciBEVCBvbmx5Cj4gc2VlbXMgdG8gYmUgYSBub24tc3RhcnRlciwgdGhlIEFQSSBz aG91bGQgYmUgaGlkaW5nIGRldGFpbHMgb2YgdGhlCj4gZmlybXdhcmUgaW50ZXJmYWNlLgoKSSBh Z3JlZSwgYnV0IGFzIHRoaXMgaXMgUkZDLCBub3QgZXZlcnl0aGluZyBpcyBmaW5pc2hlZC4gSXQg c2VlbXMgSSBoYXZlCmZvcmdvdHRlbiB0byBtZW50aW9uIGl0IGNsZWFybHkgaW4gY292ZXIKbGV0 dGVyLgpBbnl3YXkgaXQgc2VlbXMgSSBzaG91bGQgYWRqdXN0IHBhdGNoc2V0IGFuZCBtb3ZlIG1h dGNoaW5nIGNvZGUgZnJvbQpyZXN0cmFjay90cmFjayBjb3JlIHRvIHNwZWNpZmljIGZyYW1ld29y a3MuClRoaXMgd2F5IGFueSBjdXJyZW50IG9yIGZ1dHVyZSBsb29rdXAgbWV0aG9kIHNob3VsZCBi ZSBzdXBwb3J0ZWQuCgpCdXQgdGhlIG1haW4gcHVycG9zZSBvZiB0aGlzIHBhdGNoc2V0IGlzIHRv IGdldCBvcGluaW9ucywgaWYgdGhlIG1haW4KaWRlYXMgYXJlIE9LLiBBbmQgaWYgdGhlIHBhdGNo c2V0IGNhbiBiZQpldmVudHVhbGx5IGFjY2VwdGVkLgoKUmVnYXJkcwpBbmRyemVqCgpfX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGlu ZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVlZGVza3RvcC5vcmcKaHR0cDovL2xpc3RzLmZyZWVk ZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaS1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 From: a.hajda@samsung.com (Andrzej Hajda) Date: Thu, 11 Dec 2014 11:49:54 +0100 Subject: [RFC 04/15] regulator: add restrack support In-Reply-To: <20141210160720.GS11764@sirena.org.uk> References: <1418226513-14105-1-git-send-email-a.hajda@samsung.com> <1418226513-14105-5-git-send-email-a.hajda@samsung.com> <20141210160720.GS11764@sirena.org.uk> Message-ID: <548976D2.7080005@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Mark, On 12/10/2014 05:07 PM, Mark Brown wrote: > On Wed, Dec 10, 2014 at 04:48:22PM +0100, Andrzej Hajda wrote: >> Regulators supports various methods of lookup. >> The patch adds restrack support only to DT based regulators. > Why, what does this mean and how might one use it? I've not looked at > the code since I don't know what it's supposed to accomplish... Looking at this patch makes no sense without looking at cover letter or at the patch adding restrack framework. In short adding restrack support to regulators will allow to: - proper handle regulator provider unbind/re-bind, currently it results in oopses, crashes and hangs, - avoid late probe due to deferred probing, currently if probe is deferred, re-probe occurs in late initcall, - track appearance of resources which can alter behavior of the driver if present but they are not required, I am not sure if there are use cases for it in case of regulators, but other resources have such use cases, - as a bonus we can have simpler allocation of various resources, please look at cover letter for example. > > One very high level thing is that anything that only works for DT only > seems to be a non-starter, the API should be hiding details of the > firmware interface. I agree, but as this is RFC, not everything is finished. It seems I have forgotten to mention it clearly in cover letter. Anyway it seems I should adjust patchset and move matching code from restrack/track core to specific frameworks. This way any current or future lookup method should be supported. But the main purpose of this patchset is to get opinions, if the main ideas are OK. And if the patchset can be eventually accepted. Regards Andrzej From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757299AbaLKKuS (ORCPT ); Thu, 11 Dec 2014 05:50:18 -0500 Received: from mailout2.w1.samsung.com ([210.118.77.12]:34577 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756681AbaLKKuP (ORCPT ); Thu, 11 Dec 2014 05:50:15 -0500 X-AuditID: cbfec7f5-b7fc86d0000066b7-fc-548976e349fd Message-id: <548976D2.7080005@samsung.com> Date: Thu, 11 Dec 2014 11:49:54 +0100 From: Andrzej Hajda User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.3.0 MIME-version: 1.0 To: Mark Brown Cc: open list , Marek Szyprowski , Greg Kroah-Hartman , Mike Turquette , Russell King , Linus Walleij , Alexandre Courbot , Thierry Reding , Inki Dae , Kishon Vijay Abraham I , Liam Girdwood , Grant Likely , Rob Herring , "moderated list:ARM/CLKDEV SUPPORT" , "open list:GPIO SUBSYSTEM" , "open list:DRM PANEL DRIVERS" , "moderated list:ARM/S5P EXYNOS AR..." , "open list:OPEN FIRMWARE AND..." , boris.brezillon@free-electrons.com Subject: Re: [RFC 04/15] regulator: add restrack support References: <1418226513-14105-1-git-send-email-a.hajda@samsung.com> <1418226513-14105-5-git-send-email-a.hajda@samsung.com> <20141210160720.GS11764@sirena.org.uk> In-reply-to: <20141210160720.GS11764@sirena.org.uk> Content-type: text/plain; charset=windows-1252 Content-transfer-encoding: 7bit X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprJIsWRmVeSWpSXmKPExsVy+t/xy7qPyzpDDJbP0bU48GIhi8XUh0/Y LOYfOcdqceXrezaLc68esVgc+LOD0aJ58Xo2i0n3J7BYXHjaw2bx7UoHk8WUP8uZLDY9vsZq sXn+H0aLy7vmsFnMOL+PyeL2ZV6LtUfusls8nXCRzaJ17xF2i5+75rE4iHi0NPeweTzZdJHR Y+esu+wem1Z1snncubaHzWP/3DXsHve7jzN5bF5S79G3ZRWjx/Eb25k8Pm+SC+CO4rJJSc3J LEst0rdL4Mp4Ovsoa8FF3oqH5y6yNTB+4upi5OSQEDCReHDxIjOELSZx4d56ti5GLg4hgaWM Eg8mtzOCJIQEPjFKNM7iB7F5BbQkFn2fyAJiswioSrxoe88GYrMJaEr83XwTzBYViJD4sOor G0S9oMSPyffA6kUElCWuft8LZjMLzGGX2LzLHMQWFrCQmH1iETvE4mWMEnsWvQNr5hQwlnj8 8xfQdRxADXoS9y9qQfTKS2xe85Z5AqPALCQrZiFUzUJStYCReRWjaGppckFxUnqukV5xYm5x aV66XnJ+7iZGSHR+3cG49JjVIUYBDkYlHt6M+M4QIdbEsuLK3EOMEhzMSiK8VhFAId6UxMqq 1KL8+KLSnNTiQ4xMHJxSDYyBOxIPcrXe7ZHduuv+ybzqJzm2ukoc52t6V3zNiOYv7XKXvVXN l+t+4Ufn6vUx1xyTT7Jnavla5yystWwt7Ht2Pfpfz8m9+rwzRM/5XXlyQeeefDnze8P5oUv7 2BQfBKZP6DooPHOLwcrQrfut7h/csIzZTOrKmQ7mSFk+8XuZ+3tLPf6fi1RiKc5INNRiLipO BAC6c7/nrAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mark, On 12/10/2014 05:07 PM, Mark Brown wrote: > On Wed, Dec 10, 2014 at 04:48:22PM +0100, Andrzej Hajda wrote: >> Regulators supports various methods of lookup. >> The patch adds restrack support only to DT based regulators. > Why, what does this mean and how might one use it? I've not looked at > the code since I don't know what it's supposed to accomplish... Looking at this patch makes no sense without looking at cover letter or at the patch adding restrack framework. In short adding restrack support to regulators will allow to: - proper handle regulator provider unbind/re-bind, currently it results in oopses, crashes and hangs, - avoid late probe due to deferred probing, currently if probe is deferred, re-probe occurs in late initcall, - track appearance of resources which can alter behavior of the driver if present but they are not required, I am not sure if there are use cases for it in case of regulators, but other resources have such use cases, - as a bonus we can have simpler allocation of various resources, please look at cover letter for example. > > One very high level thing is that anything that only works for DT only > seems to be a non-starter, the API should be hiding details of the > firmware interface. I agree, but as this is RFC, not everything is finished. It seems I have forgotten to mention it clearly in cover letter. Anyway it seems I should adjust patchset and move matching code from restrack/track core to specific frameworks. This way any current or future lookup method should be supported. But the main purpose of this patchset is to get opinions, if the main ideas are OK. And if the patchset can be eventually accepted. Regards Andrzej