From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: Re: [PATCH] eeprom: at24: correctly set the size for at24mac402 Date: Tue, 28 Nov 2017 20:39:31 +0100 Message-ID: References: <20171127210613.9140-1-brgl@bgdev.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wm0-f67.google.com ([74.125.82.67]:39824 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752618AbdK1Tjk (ORCPT ); Tue, 28 Nov 2017 14:39:40 -0500 In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Bartosz Golaszewski Cc: Andy Shevchenko , Claudiu Beznea , linux-i2c , "linux-kernel@vger.kernel.org" , stable@vger.kernel.org Am 28.11.2017 um 13:09 schrieb Andy Shevchenko: > 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. >> > > Reviewed-by: Andy Shevchenko > Looks good also to me. >> Cc: stable@vger.kernel.org >> Fixes: 0b813658c115 ("eeprom: at24: add support for at24mac series") >> Signed-off-by: Bartosz Golaszewski >> --- >> drivers/misc/eeprom/at24.c | 10 ++++++++++ >> 1 file changed, 10 insertions(+) >> >> diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c >> index e0b4b36ef010..783244b485cc 100644 >> --- a/drivers/misc/eeprom/at24.c >> +++ b/drivers/misc/eeprom/at24.c >> @@ -730,6 +730,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) >> dev_warn(&client->dev, >> "page_size looks suspicious (no power of 2)!\n"); >> >> + /* >> + * 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) >> + chip.byte_len = 6; >> + >> /* Use I2C operations unless we're stuck with SMBus extensions. */ >> if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { >> if (chip.flags & AT24_FLAG_ADDR16) >> -- >> 2.15.0 >> > > >