From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753188AbdK1KZR (ORCPT ); Tue, 28 Nov 2017 05:25:17 -0500 Received: from mail-qt0-f176.google.com ([209.85.216.176]:33732 "EHLO mail-qt0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752806AbdK1KZO (ORCPT ); Tue, 28 Nov 2017 05:25:14 -0500 X-Google-Smtp-Source: AGs4zMZauNIhRs1kbaD7KdNcJk+DL9IOURs14ZBwyMa6g78MU4idqljPq5Cr6ANm3rOLfxuqIxS816a+hCDg6BbFlw8= MIME-Version: 1.0 In-Reply-To: <20171127210613.9140-1-brgl@bgdev.pl> References: <20171127210613.9140-1-brgl@bgdev.pl> From: Andy Shevchenko Date: Tue, 28 Nov 2017 12:25:12 +0200 Message-ID: Subject: Re: [PATCH] eeprom: at24: correctly set the size for at24mac402 To: Bartosz Golaszewski Cc: Heiner Kallweit , Claudiu Beznea , linux-i2c , "linux-kernel@vger.kernel.org" , stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 27, 2017 at 11:06 PM, Bartosz Golaszewski wrote: > There's an ilog2() expansion in AT24_DEVICE_MAGIC() which rounds down > the actual size of EUI-48 byte array in at24mac402 eeproms to 4 from 6, > making it impossible to read it all. > > Fix it by manually adjusting the value in probe(). > > This patch contains a temporary fix that is suitable for stable > branches. Eventually we'll probably remove the call to ilog2() while > converting the magic values to actual structs. > + /* > + * REVISIT: the size of the EUI-48 byte array is 6 in at24mac402, while > + * the call to ilog2() in AT24_DEVICE_MAGIC() rounds it down to 4. > + * > + * Eventually we'll get rid of the magic values altoghether in favor of > + * real structs, but for now just manually set the right size. > + */ > + if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4) I didn't check, but do we need to test for len == 4 at all? > + chip.byte_len = 6; -- With Best Regards, Andy Shevchenko