From mboxrd@z Thu Jan 1 00:00:00 1970 From: "De Marchi, Lucas" Subject: Re: [PATCH] i2c: designware: use enable on resume instead initialization Date: Wed, 24 Jun 2015 12:56:19 +0000 Message-ID: <1435150578.1075.5.camel@intel.com> References: <1433785828-4100-1-git-send-email-lucas.de.marchi@gmail.com> <20150609085146.GD1478@lahna.fi.intel.com> <20150610070722.GM1478@lahna.fi.intel.com> <20150624112723.GE827@lahna.fi.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20150624112723.GE827-3PARRvDOhMZrdx17CPfAsdBPR1lH4CV8@public.gmane.org> Content-Language: en-US Content-ID: Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org" , "christian.ruppert-Yycd8EPnGM5BDgjK7y7TUQ@public.gmane.org" Cc: "lucas.de.marchi-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org" , "Mello, Fabio" , "jarkko.nikula-VuQAYsv1563Yd54FQh9/CA@public.gmane.org" , "christian.ruppert-ux6zf3SgZrrQT0dZR+AlfA@public.gmane.org" , "linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-i2c@vger.kernel.org T24gV2VkLCAyMDE1LTA2LTI0IGF0IDE0OjI3ICswMzAwLCBNaWthIFdlc3RlcmJlcmcgd3JvdGU6 DQo+IE9uIFdlZCwgSnVuIDI0LCAyMDE1IGF0IDA5OjM2OjQzQU0gKzAyMDAsIGNocmlzdGlhbi5y dXBwZXJ0QGFsaXRlY2guY29tIHdyb3QNCj4gZToNCj4gPiBEZWFyIEx1Y2FzLA0KPiA+IA0KPiA+ IEx1Y2FzIERlIE1hcmNoaSA8bHVjYXMuZGUubWFyY2hpQGdtYWlsLmNvbT4gd3JvdGUgb24gMjMu MDYuMjAxNSAxOTowMjowMzoNCj4gPiA+IE9uIFR1ZSwgSnVuIDIzLCAyMDE1IGF0IDE6NDUgUE0s ICA8Y2hyaXN0aWFuLnJ1cHBlcnRAYWxpdGVjaC5jb20+IHdyb3RlOg0KPiA+ID4gPiBIZWxsbywN Cj4gPiA+ID4gDQo+ID4gPiA+IENocmlzdGlhbiBSdXBwZXJ0L0FMaV9HVkEvQUxpIHdyb3RlIG9u IDEwLjA2LjIwMTUgMTc6MDU6MTY6DQo+ID4gPiBbLi4uXQ0KPiA+ID4gPiBUaGUgcmVzdWx0IGlz IG5vdCB2ZXJ5IGVuY291cmFnaW5nOiBPdXQgb2YgZml2ZSAoaWRlbnRpY2FsKSBkZXNpZ253YXJl IA0KPiA+ID4gPiANCj4gPiBpMmMNCj4gPiA+ID4gY29udHJvbGxlcnMgd2UgaGF2ZSBvbiBteSB0 ZXN0IFNPQywgdGhlIGZpcnN0IG9uZSBpbml0aWFsaXNlcyBwcm9wZXJseSANCj4gPiA+ID4gDQo+ ID4gYnV0DQo+ID4gPiA+IHRoZSBzZWNvbmQgb25lIGdldHMgc3R1Y2sgaW4gdGhlIGZhbW91cyBp cnEgbG9vcCByaWdodCBhd2F5IHdoZW4gdGhlDQo+ID4gPiA+IG1vZHVsZSBpcyBlbmFibGVkIGlu IGkyY19kd19pbml0LiBUaGUgc3lzdGVtIG5ldmVyIGdldHMgYXJvdW5kIHRvIHRyeQ0KPiA+ID4g DQo+ID4gPiBBcmUgeW91IHVzaW5nIHRoZSBwY2kgb3IgcGxhdGZvcm0gZHJpdmVyPyAgSSBub3Rp Y2VkIHllc3RlcmRheSB0aGUgcGNpDQo+ID4gPiB2ZXJzaW9uIGlzIGZhaWxpbmcgaGVyZSB3aXRo IGEgTlVMTCBwb2ludGVyIGRlcmVmZXJlbmNlLg0KPiA+IA0KPiA+IFRoZSB0ZXN0IHdhcyBwZXJm b3JtZWQgd2l0aCB0aGUgcGxhdGZvcm0gZHJpdmVyIChpbnN0YW50aWF0ZWQgdGhyb3VnaCANCj4g PiBkZXZpY2UgdHJlZSkuDQo+ID4gSSBqdXN0IHJlLWNoZWNrZWQgYW5kIHRoZSB1bHRpbWF0ZSBw cm9ibGVtIHdoaWNoIGhhbmdzL2tpbGxzIHRoZSBzeXN0ZW0gaW4gDQo+ID4gDQo+ID4gbXkgY2Fz ZSBpcyB0aGUgSVJRIGxvb3AuDQo+ID4gSSBoYXZlbid0IG9ic2VydmVkIGFueSBOVUxMIHBvaW50 ZXIgZGVyZWZlcmVuY2VzIG9uIHRoZSByb2FkLg0KPiANCj4gVGhhbmtzIENocmlzdGlhbiBmb3Ig dGVzdGluZy4NCj4gDQo+IFNpbmNlIHRoZSBwYXRjaCBjYXVzZXMgcHJvYmxlbXMgb24geW91ciBo YXJkd2FyZSwgSSBkb24ndCB0aGluayBpdCBpcw0KPiBnb29kIGlkZWEgdG8gbWVyZ2UgaXQuDQoN Cg0KWWVhaCwgYnV0IGl0IHdvdWxkIGJlIGJhZCB0byBpZ25vcmUgdGhlIHByb2JsZW0gYXMgd2Vs bC4gVGhlIHdheSBpdCBpcyBub3cNCmtpbGxzIGFueSBwb3NzaWJpbGl0eSBvZiB1c2luZyBEVyBj b250cm9sbGVyIGZvciByZWFkaW5nIHNlbnNvcnMgbGlrZQ0KZ3lyb3Njb3BlLCBhY2NlbGVyb21l dGVyLCBiYXJvbWV0ZXIgdGhhdCBoYXZlIGhpZ2hlciBzYW1wbGluZyByYXRlIGV0Yy4gIEknbGwN CnRyeSB0byBjb21lIHVwIHdpdGggYSBuZXcgcGF0Y2ggYnV0IHNpbmNlIEkgY2FuJ3QgcmVwcm9k dWNlIHRoZSBwcm9ibGVtIGhlcmUNCml0J2QgYmUgZ29vZCB0byBrbm93IGlmIHRoZXJlJ3MgYW55 IG1lYW5zIGZvciBtZSB0byB0ZXN0LiAgV2hhdCBkbyB5b3UgdGhpbmsNCnRoYXQgY291bGQgYmUg ZG9uZT8gTWF5YmUgcHV0dGluZyB0aGUgY29udHJvbGxlciB0byBzbGVlcCBvbmx5IGluIGNhc2Ug b2YNCmVycm9ycz8NCg0KdGhhbmtzDQoNCi0tIA0KTHVjYXMgRGUgTWFyY2hp From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752940AbbFXM4l (ORCPT ); Wed, 24 Jun 2015 08:56:41 -0400 Received: from mga09.intel.com ([134.134.136.24]:44687 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752756AbbFXM41 (ORCPT ); Wed, 24 Jun 2015 08:56:27 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,671,1427785200"; d="scan'208";a="513508441" From: "De Marchi, Lucas" To: "mika.westerberg@linux.intel.com" , "christian.ruppert@alitech.com" CC: "lucas.de.marchi@gmail.com" , "linux-kernel@vger.kernel.org" , "wsa@the-dreams.de" , "Mello, Fabio" , "jarkko.nikula@linux.intel.com" , "christian.ruppert@abilis.com" , "linux-i2c@vger.kernel.org" Subject: Re: [PATCH] i2c: designware: use enable on resume instead initialization Thread-Topic: [PATCH] i2c: designware: use enable on resume instead initialization Thread-Index: AQHQohQERxwB9CtwO0+ilrKbreVIMJ2kVDgAgAChSICAANPhAIAUmetPgAB6i4CAAPRhgIAAQHOAgAAY2AA= Date: Wed, 24 Jun 2015 12:56:19 +0000 Message-ID: <1435150578.1075.5.camel@intel.com> References: <1433785828-4100-1-git-send-email-lucas.de.marchi@gmail.com> <20150609085146.GD1478@lahna.fi.intel.com> <20150610070722.GM1478@lahna.fi.intel.com> <20150624112723.GE827@lahna.fi.intel.com> In-Reply-To: <20150624112723.GE827@lahna.fi.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.254.76.209] Content-Type: text/plain; charset="utf-8" Content-ID: MIME-Version: 1.0 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 nfs id t5OCukBb017166 On Wed, 2015-06-24 at 14:27 +0300, Mika Westerberg wrote: > On Wed, Jun 24, 2015 at 09:36:43AM +0200, christian.ruppert@alitech.com wrot > e: > > Dear Lucas, > > > > Lucas De Marchi wrote on 23.06.2015 19:02:03: > > > On Tue, Jun 23, 2015 at 1:45 PM, wrote: > > > > Hello, > > > > > > > > Christian Ruppert/ALi_GVA/ALi wrote on 10.06.2015 17:05:16: > > > [...] > > > > The result is not very encouraging: Out of five (identical) designware > > > > > > i2c > > > > controllers we have on my test SOC, the first one initialises properly > > > > > > but > > > > the second one gets stuck in the famous irq loop right away when the > > > > module is enabled in i2c_dw_init. The system never gets around to try > > > > > > Are you using the pci or platform driver? I noticed yesterday the pci > > > version is failing here with a NULL pointer dereference. > > > > The test was performed with the platform driver (instantiated through > > device tree). > > I just re-checked and the ultimate problem which hangs/kills the system in > > > > my case is the IRQ loop. > > I haven't observed any NULL pointer dereferences on the road. > > Thanks Christian for testing. > > Since the patch causes problems on your hardware, I don't think it is > good idea to merge it. Yeah, but it would be bad to ignore the problem as well. The way it is now kills any possibility of using DW controller for reading sensors like gyroscope, accelerometer, barometer that have higher sampling rate etc. I'll try to come up with a new patch but since I can't reproduce the problem here it'd be good to know if there's any means for me to test. What do you think that could be done? Maybe putting the controller to sleep only in case of errors? thanks -- Lucas De Marchi{.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I