From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ankitprasad Sharma Subject: Re: [PATCH 10/11] acpi: Export acpi_bus_type Date: Mon, 18 Jan 2016 14:31:00 +0530 Message-ID: <1453107660.10582.31.camel@ankitprasad-desktop> References: <1452752207-30382-1-git-send-email-ankitprasad.r.sharma@intel.com> <1452752207-30382-11-git-send-email-ankitprasad.r.sharma@intel.com> <19135964.pq7BquODL6@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <19135964.pq7BquODL6@vostro.rjw.lan> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: "Rafael J. Wysocki" Cc: intel-gfx@lists.freedesktop.org, shashidhar.hiremath@intel.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, akash.goel@intel.com, Len Brown List-Id: linux-acpi@vger.kernel.org T24gRnJpLCAyMDE2LTAxLTE1IGF0IDE1OjUxICswMTAwLCBSYWZhZWwgSi4gV3lzb2NraSB3cm90 ZToKPiBPbiBUaHVyc2RheSwgSmFudWFyeSAxNCwgMjAxNiAxMTo0Njo0NiBBTSBhbmtpdHByYXNh ZC5yLnNoYXJtYUBpbnRlbC5jb20gd3JvdGU6Cj4gPiBGcm9tOiBBbmtpdHByYXNhZCBTaGFybWEg PGFua2l0cHJhc2FkLnIuc2hhcm1hQGludGVsLmNvbT4KPiA+IAo+ID4gU29tZSBtb2R1bGVzLCBs aWtlIGk5MTUua28sIG5lZWRzIHRvIGRldGVjdCB3aGVuIGNlcnRhaW4gQUNQSSBmZWF0dXJlcwo+ ID4gYXJlIGFjdGl2ZSBpbm9yZGVyIHRvIHByZXZlbnQgY29ycnVwdGlvbiBvbiBjb250ZW5kZWQg cmVzb3VyY2VzLgo+ID4gSW4gcGFydGljdWxhciwgdXNlIG9mIEJJT1MgUmFwaWRTdGFydCBUZWNo bm9sb2d5IG1heSBjb3JydXB0IHRoZSBjb250ZW50cwo+ID4gb2YgdGhlIHJlc2VydmVkIGdyYXBo aWNzIG1lbW9yeSwgZHVlIHRvIHVuYWxhcm1lZCBoaWJlcm5hdGlvbi4gSW4gd2hpY2gKPiA+IGNh c2UgaTkxNS5rbyBjYW5ub3QgYXNzdW1lIHRoYXQgaXQgKHJlc2VydmVkIGdmeCBtZW1vcnkpIHJl bWFpbnMKPiA+IHVubW9kaWZpZWQgYW5kIG11c3QgcmVjcmVhdGUgdGVoIGNvbnRlbnRzIGFuZCBp bXBvcnRhbnRseSBub3QgdXNlIGl0IHRvCj4gPiBzdG9yZSB1bnJlY292ZXJhYmxlIHVzZXIgZGF0 YS4KPiA+IAo+ID4gU2lnbmVkLW9mZi1ieTogQW5raXRwcmFzYWQgU2hhcm1hIDxhbmtpdHByYXNh ZC5yLnNoYXJtYUBpbnRlbC5jb20+Cj4gPiBDYzogIlJhZmFlbCBKLiBXeXNvY2tpIiA8cmp3QHJq d3lzb2NraS5uZXQ+Cj4gPiBDYzogTGVuIEJyb3duIDxsZW5iQGtlcm5lbC5vcmc+Cj4gPiBDYzog bGludXgtYWNwaUB2Z2VyLmtlcm5lbC5vcmcKPiA+IENjOiBsaW51eC1rZXJuZWxAdmdlci5rZXJu ZWwub3JnCj4gPiAtLS0KPiA+ICBkcml2ZXJzL2FjcGkvYnVzLmMgfCAxICsKPiA+ICAxIGZpbGUg Y2hhbmdlZCwgMSBpbnNlcnRpb24oKykKPiA+IAo+ID4gZGlmZiAtLWdpdCBhL2RyaXZlcnMvYWNw aS9idXMuYyBiL2RyaXZlcnMvYWNwaS9idXMuYwo+ID4gaW5kZXggYTIxMmNlZi4uNjk1MDljNyAx MDA2NDQKPiA+IC0tLSBhL2RyaXZlcnMvYWNwaS9idXMuYwo+ID4gKysrIGIvZHJpdmVycy9hY3Bp L2J1cy5jCj4gPiBAQCAtODE0LDYgKzgxNCw3IEBAIHN0cnVjdCBidXNfdHlwZSBhY3BpX2J1c190 eXBlID0gewo+ID4gIAkucmVtb3ZlCQk9IGFjcGlfZGV2aWNlX3JlbW92ZSwKPiA+ICAJLnVldmVu dAkJPSBhY3BpX2RldmljZV91ZXZlbnQsCj4gPiAgfTsKPiA+ICtFWFBPUlRfU1lNQk9MX0dQTChh Y3BpX2J1c190eXBlKTsKPiA+ICAKPiA+ICAvKiAtLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0t LS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tLQo+ID4gICAgICAg ICAgICAgICAgICAgICAgICAgICAgICAgSW5pdGlhbGl6YXRpb24vQ2xlYW51cAo+ID4gCj4gCj4g Tm8uCj4gCj4gSSBzZWUgbm8gcmVhc29uIHdoYXRzb2V2ZXIgZm9yIGRvaW5nIHRoaXMuCj4gCj4g VGhhbmtzLAo+IFJhZmFlbApIaSBSYWZhZWwsCgpUaGFua3MgZm9yIHRoZSByZXNwb25zZS4KCkNh biB5b3UgcGxlYXNlIGhlbHAgbWUgd2l0aCwgaG93IHRvIGRldGVjdCB0aGUgcHJlc2VuY2Ugb2Yg YSBjZXJ0YWluCmFjcGkgZGV2aWNlIHVzaW5nIGl0cyBpZCAoZm9yIGV4YW1wbGUsIElOVDMzOTIg Zm9yIEludGVsIFJTVCBkZXZpY2UpPyAKCkFzIHlvdSBtaWdodCBoYXZlIHNlZW4gKGluIHRoZSBu ZXh0IHBhdGNoIGluIHRoaXMgc2VyaWVzKSwgdGhhdCB3ZSB1c2UKdGhpcyBzeW1ib2wgKGFjcGlf YnVzX3R5cGUpIHRvIGl0ZXJhdGUgb3ZlciBhbGwgdGhlIGRldmljZXMgcmVnaXN0ZXJlZApvbiBh Y3BpIGJ1cywgdG8gY2hlY2sgaWYgdGhlcmUgaXMgYSBkZXZpY2Ugd2l0aCBpZCBJTlQzMzkyIHBy ZXNlbnQgb3IKbm90LgoKVGhhbmtzLApBbmtpdAoKX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX18KSW50ZWwtZ2Z4IG1haWxpbmcgbGlzdApJbnRlbC1nZnhAbGlz dHMuZnJlZWRlc2t0b3Aub3JnCmh0dHA6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9s aXN0aW5mby9pbnRlbC1nZngK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754346AbcARJWf (ORCPT ); Mon, 18 Jan 2016 04:22:35 -0500 Received: from mga02.intel.com ([134.134.136.20]:49915 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753780AbcARJWc (ORCPT ); Mon, 18 Jan 2016 04:22:32 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,312,1449561600"; d="scan'208";a="892873645" Message-ID: <1453107660.10582.31.camel@ankitprasad-desktop> Subject: Re: [PATCH 10/11] acpi: Export acpi_bus_type From: Ankitprasad Sharma To: "Rafael J. Wysocki" Cc: intel-gfx@lists.freedesktop.org, akash.goel@intel.com, shashidhar.hiremath@intel.com, tvrtko.ursulin@linux.intel.com, Len Brown , linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org Date: Mon, 18 Jan 2016 14:31:00 +0530 In-Reply-To: <19135964.pq7BquODL6@vostro.rjw.lan> References: <1452752207-30382-1-git-send-email-ankitprasad.r.sharma@intel.com> <1452752207-30382-11-git-send-email-ankitprasad.r.sharma@intel.com> <19135964.pq7BquODL6@vostro.rjw.lan> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2016-01-15 at 15:51 +0100, Rafael J. Wysocki wrote: > On Thursday, January 14, 2016 11:46:46 AM ankitprasad.r.sharma@intel.com wrote: > > From: Ankitprasad Sharma > > > > Some modules, like i915.ko, needs to detect when certain ACPI features > > are active inorder to prevent corruption on contended resources. > > In particular, use of BIOS RapidStart Technology may corrupt the contents > > of the reserved graphics memory, due to unalarmed hibernation. In which > > case i915.ko cannot assume that it (reserved gfx memory) remains > > unmodified and must recreate teh contents and importantly not use it to > > store unrecoverable user data. > > > > Signed-off-by: Ankitprasad Sharma > > Cc: "Rafael J. Wysocki" > > Cc: Len Brown > > Cc: linux-acpi@vger.kernel.org > > Cc: linux-kernel@vger.kernel.org > > --- > > drivers/acpi/bus.c | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c > > index a212cef..69509c7 100644 > > --- a/drivers/acpi/bus.c > > +++ b/drivers/acpi/bus.c > > @@ -814,6 +814,7 @@ struct bus_type acpi_bus_type = { > > .remove = acpi_device_remove, > > .uevent = acpi_device_uevent, > > }; > > +EXPORT_SYMBOL_GPL(acpi_bus_type); > > > > /* -------------------------------------------------------------------------- > > Initialization/Cleanup > > > > No. > > I see no reason whatsoever for doing this. > > Thanks, > Rafael Hi Rafael, Thanks for the response. Can you please help me with, how to detect the presence of a certain acpi device using its id (for example, INT3392 for Intel RST device)? As you might have seen (in the next patch in this series), that we use this symbol (acpi_bus_type) to iterate over all the devices registered on acpi bus, to check if there is a device with id INT3392 present or not. Thanks, Ankit