Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759055AbZKYREM (ORCPT ); Wed, 25 Nov 2009 12:04:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758994AbZKYREJ (ORCPT ); Wed, 25 Nov 2009 12:04:09 -0500 Received: from mx1.emlix.com ([193.175.82.87]:41763 "EHLO mx1.emlix.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758969AbZKYREG (ORCPT ); Wed, 25 Nov 2009 12:04:06 -0500 X-Greylist: delayed 1973 seconds by postgrey-1.27 at vger.kernel.org; Wed, 25 Nov 2009 12:04:06 EST From: Johannes Weiner To: Alessandro Zummo , Paul Gortmaker Cc: Andrew Morton , rtc-linux@googlegroups.com, linux-kernel@vger.kernel.org Subject: [patch 1/3] rtc-x1205: fix rtc_time to y2k register value conversion Date: Wed, 25 Nov 2009 17:32:14 +0100 Message-Id: <1259166736-31006-1-git-send-email-jw@emlix.com> Organization: emlix gmbh, Goettingen, Germany Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1625 Lines: 43 The possible CCR_Y2K register values are 19 or 20 and struct rtc_time's tm_year is in years since 1900. The function translating rtc_time to register values assumes tm_year to be years since first christmas, though, and we end up storing 0 or 1 in the CCR_Y2K register, which the hardware does not refuse to do. A subsequent probing of the clock fails due to the invalid value range in the register, though. [ And if it didn't, reading the clock would yield a bogus year because the function translating registers to tm_year is assuming a register value of 19 or 20. ] This fixes the conversion from years since 1900 in tm_year to the corresponding CCR_Y2K value of 19 or 20. Signed-off-by: Johannes Weiner --- drivers/rtc/rtc-x1205.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/rtc/rtc-x1205.c b/drivers/rtc/rtc-x1205.c index 310c107..cc9ba47 100644 --- a/drivers/rtc/rtc-x1205.c +++ b/drivers/rtc/rtc-x1205.c @@ -195,7 +195,7 @@ static int x1205_set_datetime(struct i2c_client *client, struct rtc_time *tm, /* year, since the rtc epoch*/ buf[CCR_YEAR] = bin2bcd(tm->tm_year % 100); buf[CCR_WDAY] = tm->tm_wday & 0x07; - buf[CCR_Y2K] = bin2bcd(tm->tm_year / 100); + buf[CCR_Y2K] = bin2bcd((tm->tm_year + 1900) / 100); } /* If writing alarm registers, set compare bits on registers 0-4 */ -- 1.6.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/