From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH 4/8] minnowboard: Add base platform driver for the MinnowBoard Date: Wed, 26 Jun 2013 04:52:46 +0000 Message-ID: <1372222365.9179.4.camel@x230> References: <20130626040026.GA23621@quad.lixom.net> <1372221808.8177.52.camel@envy.home> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail-by2lp0241.outbound.protection.outlook.com ([207.46.163.241]:20742 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750766Ab3FZEwu (ORCPT ); Wed, 26 Jun 2013 00:52:50 -0400 In-Reply-To: <1372221808.8177.52.camel@envy.home> Content-Language: en-US Content-ID: <30F4A32BAC0FE4418AF8FC999672FD01@namprd05.prod.outlook.com> Sender: platform-driver-x86-owner@vger.kernel.org List-ID: To: Darren Hart Cc: Olof Johansson , "David S. Miller" , Linux Kernel Mailing List , "H. Peter Anvin" , "peter.p.waskiewicz.jr@intel.com" , "andriy.shevchenko@linux.intel.com" , "danders@circuitco.com" , "vishal.l.verma@intel.com" , Grant Likely , Linus Walleij , Richard Purdie , "platform-driver-x86@vger.kernel.org" T24gVHVlLCAyMDEzLTA2LTI1IGF0IDIxOjQzIC0wNzAwLCBEYXJyZW4gSGFydCB3cm90ZToNCg0K PiAxKSBJIG5lZWQgdGltZSwgcG9zc2libHkgYSBjb3VwbGUgb2YgbW9udGhzLCB0byBnZXQgcHJv cGVyIEFDUEkgc3VwcG9ydA0KPiBmb3IgdGhlc2UgZHJpdmVycyBpbnRvIHRoZSBmaXJtd2FyZS4g VGhlbiBJIGNhbiByZXdyaXRlIHRoZXNlIGFzIEFDUEkNCj4gZHJpdmVycyBhcyBpcyBwcm9wZXIg Zm9yIGFuIHg4NiBib2FyZC4gSSd2ZSBhbHJlYWR5IHN0YXJ0ZWQgZG93biB0aGlzDQo+IHBhdGgu DQoNCkEgY291cGxlIG9mIG1vbnRocyBwdXNoZXMgeW91IGJhY2sgb25lIGtlcm5lbCByZWxlYXNl LiBJdCdzIG5vdCBhIGh1Z2UNCmRlYWwuIEkgdGhpbmsgSSBzaWRlIHdpdGggT2xvZiBoZXJlIC0g dGhlIGtlcm5lbCBkZXZlbG9wZXJzIGhhdmUgcHVzaGVkDQpiYWNrIGFnYWluc3QgaGFyZGNvZGVk IGFuZCBOSUhlZCBBUk0gZGV2aWNlIGRlc2NyaXB0b3JzLCBhbmQgZ2l2ZW4gdGhhdA0Kd2UgaGF2 ZSBhIHBlcmZlY3RseSByZWFzb25hYmxlIHN0YW5kYXJkIGluIHRoZSBYODYgd29ybGQgKGllLCBB Q1BJKSwgSSdtDQpub3QgZW50aHVzaWFzdGljIGFib3V0IG1lcmdpbmcgc29tZXRoaW5nIHRoYXQn cyAoYSkgZ29pbmcgdG8gYmUNCnN1cGVyc2VkZWQgaW4gdGhlIG5lYXIgZnV0dXJlIGFuZCAoYikg bWF5IGVuZCB1cCBzZXJ2aW5nIGFzIGFuIGV4YW1wbGUNCnRvIG90aGVycyB3aG8gdGhpbmsgdGhp cyBpcyBvay4NCg0KRG8gdGhlc2UgYm9hcmRzIGN1cnJlbnRseSBib290IGFueSBvdGhlciBPU2Vz Pw0KDQo+IFNlZSB3aGF0IGhhcHBlbnMgd2hlbiBjb3JlIGtlcm5lbCBwZW9wbGUgYXJlIGFsbG93 ZWQgdG8gd3JpdGUgZHJpdmVyDQo+IGNvZGU/IEhvdyBkb2VzIHRoaXMgcmVsYXRlIHRvIGNvbnZl cnRpbmcgdGhpcyBvdmVyIHRvIGFuIEFDUEkgZGV2aWNlDQo+IGRyaXZlcj8gSSBndWVzcyBJIHdv dWxkIHJlcGxhY2UgdGhlIGFib3ZlIHdpdGgNCj4gTU9EVUxFX0RFVklDRV9UQUJMRShhY3BpLCAu Li4pID8gSWYgSSBkbyB0aGUgYWJvdmUuLi4uIGlzIHRoaXMgc3RpbGwgYW4NCj4gZXZpbCBib2Fy ZC1maWxlPyBXaGF0IG1ha2VzIHRoZSBhY3BpIG1ldGhvZCBvZiBkaXNjb3ZlciBzdXBlcmlvciB0 bw0KPiBzZXR0aW5nIHVwIGxpbnV4LWhvdHBsdWcgdmlhIGRtaT8NCg0KTU9EVUxFX0RFVklDRV9U QUJMRSBpcyBpbnZpc2libGUgdG8gdGhlIHJ1bm5pbmcgZHJpdmVyLCBpdCBqdXN0IGV4cG9ydHMN Cm1ldGFkYXRhIHRoYXQgdWRldiB3aWxsIHVzZSB0byBkZWNpZGUgd2hldGhlciB0byBsb2FkIHRo ZSBkcml2ZXIuIElmIGENCmRyaXZlciBpcyBpbnRlbmRlZCB0byBkZWFsIHdpdGggYSBzcGVjaWZp YyBib2FyZCwgRE1JIG1ha2VzIHNlbnNlLiBJZg0KaXQncyBpbnRlbmRlZCB0byBkZWFsIHdpdGgg YSBzcGVjaWZpYyBBQ1BJIGRldmljZSAoaWUsIHNvbWV0aGluZyB3aXRoIGENCl9ISUQgdGhhdCBk ZWZpbmVzIHRoZSBwcm9ncmFtbWluZyBtb2RlbCksIEFDUEkgbWFrZXMgc2Vuc2UuDQoNCi0tIA0K TWF0dGhldyBHYXJyZXR0IHwgbWpnNTlAc3JjZi51Y2FtLm9yZw0K From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751282Ab3FZEww (ORCPT ); Wed, 26 Jun 2013 00:52:52 -0400 Received: from mail-by2lp0241.outbound.protection.outlook.com ([207.46.163.241]:20742 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750766Ab3FZEwu (ORCPT ); Wed, 26 Jun 2013 00:52:50 -0400 From: Matthew Garrett To: Darren Hart CC: Olof Johansson , "David S. Miller" , Linux Kernel Mailing List , "H. Peter Anvin" , "peter.p.waskiewicz.jr@intel.com" , "andriy.shevchenko@linux.intel.com" , "danders@circuitco.com" , "vishal.l.verma@intel.com" , Grant Likely , "Linus Walleij" , Richard Purdie , "platform-driver-x86@vger.kernel.org" Subject: Re: [PATCH 4/8] minnowboard: Add base platform driver for the MinnowBoard Thread-Topic: [PATCH 4/8] minnowboard: Add base platform driver for the MinnowBoard Thread-Index: AQHOcg//k4Oo/fSkBUqc5+pwXHA5uZlHX0AAgAAMBgCAAAKYgA== Date: Wed, 26 Jun 2013 04:52:46 +0000 Message-ID: <1372222365.9179.4.camel@x230> References: <20130626040026.GA23621@quad.lixom.net> <1372221808.8177.52.camel@envy.home> In-Reply-To: <1372221808.8177.52.camel@envy.home> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.255.84.4] x-forefront-prvs: 08897B549D x-forefront-antispam-report: SFV:NSPM;SFS:(199002)(189002)(377424004)(24454002)(74366001)(16406001)(81342001)(81542001)(79102001)(74502001)(53806001)(74662001)(47446002)(76796001)(76786001)(56816003)(77096001)(74706001)(33646001)(33716001)(31966008)(77982001)(74876001)(69226001)(59766001)(54356001)(4396001)(47976001)(50986001)(80022001)(51856001)(49866001)(47736001)(65816001)(76482001)(63696002)(54316002)(56776001)(46102001);DIR:OUT;SFP:;SCL:1;SRVR:BY2PR05MB224;H:BY2PR05MB222.namprd05.prod.outlook.com;RD:InfoNoRecords;A:1;MX:1;LANG:en; Content-Type: text/plain; charset="utf-8" Content-ID: <30F4A32BAC0FE4418AF8FC999672FD01@namprd05.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: nebula.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id r5Q4rJNu003464 On Tue, 2013-06-25 at 21:43 -0700, Darren Hart wrote: > 1) I need time, possibly a couple of months, to get proper ACPI support > for these drivers into the firmware. Then I can rewrite these as ACPI > drivers as is proper for an x86 board. I've already started down this > path. A couple of months pushes you back one kernel release. It's not a huge deal. I think I side with Olof here - the kernel developers have pushed back against hardcoded and NIHed ARM device descriptors, and given that we have a perfectly reasonable standard in the X86 world (ie, ACPI), I'm not enthusiastic about merging something that's (a) going to be superseded in the near future and (b) may end up serving as an example to others who think this is ok. Do these boards currently boot any other OSes? > See what happens when core kernel people are allowed to write driver > code? How does this relate to converting this over to an ACPI device > driver? I guess I would replace the above with > MODULE_DEVICE_TABLE(acpi, ...) ? If I do the above.... is this still an > evil board-file? What makes the acpi method of discover superior to > setting up linux-hotplug via dmi? MODULE_DEVICE_TABLE is invisible to the running driver, it just exports metadata that udev will use to decide whether to load the driver. If a driver is intended to deal with a specific board, DMI makes sense. If it's intended to deal with a specific ACPI device (ie, something with a _HID that defines the programming model), ACPI makes sense. -- Matthew Garrett | mjg59@srcf.ucam.org {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I