From mboxrd@z Thu Jan 1 00:00:00 1970 From: Valentin Longchamp Subject: Re: [PATCH] i2c-qoriq: modified compatibility for correct prescaler Date: Fri, 14 Nov 2014 08:43:01 +0100 Message-ID: <5465B285.7070005@keymile.com> References: <1413538026-15739-1-git-send-email-valentin.longchamp@keymile.com> <1414537731.23458.120.camel@snotra.buserror.net> <5450AC85.40302@keymile.com> <20141113003418.GE2062@katana> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20141113003418.GE2062@katana> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+glppe-linuxppc-embedded-2=m.gmane.org@lists.ozlabs.org Sender: "Linuxppc-dev" To: Wolfram Sang Cc: Linux device trees , "Boschung, Rainer" , "Brunck, Holger" , Linux I2C , Scott Wood , Linux PowerPC Kernel List-Id: linux-i2c@vger.kernel.org T24gMTEvMTMvMjAxNCAwMTozNCBBTSwgV29sZnJhbSBTYW5nIHdyb3RlOgo+IAo+PiBJZiB3ZSB3 YW50ZWQgdG8gYmUgb24gdGhlIHNhZmUgc2lkZSBhbmQgc3RyaWN0IChzaW5jZSB3ZSBhcmUgbm90 IHN1cmUgdGhhdCB0aGUKPj4gaGFyZHdhcmUgaXMgMTAwJSBjb21wYXRpYmxlKSwgd2UgbWF5YmUg c2hvdWxkIGFkZCBhIGZzbCxxb3JpcS1pMmMgY29tcGF0aWJsZSB0bwo+PiB0aGUgZHJpdmVyIHRo YXQgZG9lcyB0aGUgc2FtZSBhcyBtcGM4NTQzLWkyYy4KPiAKPiBPciB5b3UgbGVhdmUgdGhlIGRy aXZlciBhcyBpcyBhbmQgdXNlIGJvdGggY29tcGF0aWJsZXM6Cj4gCj4gY29tcGF0aWJsZSA9ICJm c2wscW9yaXEtaTJjIiwgImZzbCxtcGM4NTQzLWkyYyIsICJmc2wtaTJjIjsKPiAKPiA/Cj4gCgpJ IGxpa2UgU2NvdHQncyBwcm9wb3NpdGlvbiB0byBhZGQgdGhlIHByZXNjYWxlciBpbiB0aGUgZGV2 aWNlIHRyZWUgbW9yZS4gRnJvbQp0aGUgaGFyZHdhcmUgZGVzY3JpcHRpb24gcG9pbnQgb2Ygdmll dywgaXQgbWFrZXMgbW9yZSBzZW5zZTogdGhlIGRldmljZXMgYXJlIGFsbApqdXN0IGZzbC1pMmMs IHdpdGggYSBkaWZmZXJlbnQgcHJlc2NhbGVyLiBJIGp1c3QgcXVvdGUgaXQgYmVsb3cgYXMgYSBy ZW1pbmRlci4KCj4gCj4gSWYgd2UncmUgZ29pbmcgdG8gY2hhbmdlIHRoZSBkZXZpY2UgdHJlZSBJ J2QgcmF0aGVyIGp1c3QgYWRkIGEgcHJvcGVydHkKPiB0byBzYXkgd2hhdCB0aGUgcHJlc2NhbGVy IGlzLgoKIFdlIHdvdWxkIGhvd2V2ZXIsIGxlYXZlIHRoZSBib2FyZHMnIGRldmljZSB0cmVlcyB0 aGF0IHVzZSB0aGluZ3MgbGlrZQoiZnNsLG1wYzg1NDMtaTJjIiBhcyBpcyBhbmQgaW50cm9kdWNl IHRoZSBwcmVzY2FsZXIgZm9yIHRoZSBvdGhlcnMgcmVxdWlyaW5nIGl0LgoKCk5vdyB0aGUgZHJh d2JhY2sgaXMgdGhhdCB0aGUgZHJpdmVyIHdvdWxkIHJlcXVpcmUgYSBjaGFuZ2UsIHRvIHBhcnNl IHRoaXMKcHJlc2NhbGVyIG5ldyBwcmVzY2FsZXIgcHJvcGVydHkuIFdvdWxkIHRoaXMgYmUgT0sg ZnJvbSB5b3VyIHBvaW50IG9mIHZpZXcKV29sZnJhbSA/IElmIHllcywgSSB3aWxsIHNlbmQgdGhl IHBhdGNoZXMgZm9yIGl0LgoKVmFsZW50aW4KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX18KTGludXhwcGMtZGV2IG1haWxpbmcgbGlzdApMaW51eHBwYy1kZXZA bGlzdHMub3psYWJzLm9yZwpodHRwczovL2xpc3RzLm96bGFicy5vcmcvbGlzdGluZm8vbGludXhw cGMtZGV2 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-de.keymile.com (mail-de.keymile.com [195.8.104.250]) (using TLSv1.1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 66C161A0292 for ; Fri, 14 Nov 2014 18:43:10 +1100 (AEDT) Message-ID: <5465B285.7070005@keymile.com> Date: Fri, 14 Nov 2014 08:43:01 +0100 From: Valentin Longchamp MIME-Version: 1.0 To: Wolfram Sang Subject: Re: [PATCH] i2c-qoriq: modified compatibility for correct prescaler References: <1413538026-15739-1-git-send-email-valentin.longchamp@keymile.com> <1414537731.23458.120.camel@snotra.buserror.net> <5450AC85.40302@keymile.com> <20141113003418.GE2062@katana> In-Reply-To: <20141113003418.GE2062@katana> Content-Type: text/plain; charset=windows-1252 Cc: Linux device trees , "Boschung, Rainer" , "Brunck, Holger" , Linux I2C , Scott Wood , Linux PowerPC Kernel List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 11/13/2014 01:34 AM, Wolfram Sang wrote: > >> If we wanted to be on the safe side and strict (since we are not sure that the >> hardware is 100% compatible), we maybe should add a fsl,qoriq-i2c compatible to >> the driver that does the same as mpc8543-i2c. > > Or you leave the driver as is and use both compatibles: > > compatible = "fsl,qoriq-i2c", "fsl,mpc8543-i2c", "fsl-i2c"; > > ? > I like Scott's proposition to add the prescaler in the device tree more. From the hardware description point of view, it makes more sense: the devices are all just fsl-i2c, with a different prescaler. I just quote it below as a reminder. > > If we're going to change the device tree I'd rather just add a property > to say what the prescaler is. We would however, leave the boards' device trees that use things like "fsl,mpc8543-i2c" as is and introduce the prescaler for the others requiring it. Now the drawback is that the driver would require a change, to parse this prescaler new prescaler property. Would this be OK from your point of view Wolfram ? If yes, I will send the patches for it. Valentin