From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BB876E77199 for ; Thu, 9 Jan 2025 15:48:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qcUXFptebfMrvGhDxe7112Zqb3/zYWm85RNBPbS8bvY=; b=0HBsy2UxHfffantLOqNw+zFuw9 KjXdDhoSBCr3/OR6UOTebJnfZbiRC+m/88M0uiHwN2r7imqYBzkIYQgfYqJmZjsXwbuD0DbdL6Wmx zA2tlssh77/lhdDQyWWUoZQuY4lVzxKenOPFPq4p05lgLJ89/1Y/bX+sQurSwGd8j+GhttqCedXdW eoKKP48z8+7J470boBZvPqBMQCV4b/nSNjaefC498v2pGBbZFB+kzUD9pmHK8DUiXTIz0aU9Rguiv yhYEfPsgRk8SwFUnKV+BYqKjeZffHwkVMwf7mbuUmQgjQzkM61vH5uEfcWufypQWTGxzbXdy2GnnG kh93KpaA==; 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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250109-enable-rtc-v1-2-e8223bf55bb8@baylibre.com> X-GND-Sasl: alexandre.belloni@bootlin.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250109_074645_038667_F3353AFD X-CRM114-Status: GOOD ( 19.93 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 09/01/2025 16:29:52+0100, Alexandre Mergnat wrote: > Removing the RTC_MIN_YEAR_OFFSET addition and subtraction has > introduced a regression. > > ~# hwclock -r --verbose > hwclock from util-linux 2.37.4 > System Time: 1262312013.143552 > Trying to open: /dev/rtc0 > Using the rtc interface to the clock. > Assuming hardware clock is kept in UTC time. > Waiting for clock tick... > hwclock: select() to /dev/rtc0 to wait for clock tick timed out > ...synchronization failed > > Bring back the RTC_MIN_YEAR_OFFSET to fix the RTC. > NAK, you'd have to investigate a bit more, I want to get rid of the RTC_MIN_YEAR_OFFSET insanity. > Fixes: 34bbdc12d04e ("rtc: mt6359: Add RTC hardware range and add support for start-year") > Signed-off-by: Alexandre Mergnat > --- > drivers/rtc/rtc-mt6397.c | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c > index 55e75712edd4..9930b6bdb6ca 100644 > --- a/drivers/rtc/rtc-mt6397.c > +++ b/drivers/rtc/rtc-mt6397.c > @@ -96,6 +96,12 @@ static int mtk_rtc_read_time(struct device *dev, struct rtc_time *tm) > goto exit; > } while (sec < tm->tm_sec); > > + /* HW register use 7 bits to store year data, minus > + * RTC_MIN_YEAR_OFFSET before write year data to register, and plus > + * RTC_MIN_YEAR_OFFSET back after read year from register > + */ > + tm->tm_year += RTC_MIN_YEAR_OFFSET; > + > /* HW register start mon/wday from one, but tm_mon/tm_wday start from zero. */ > tm->tm_mon--; > tm->tm_wday--; > @@ -110,6 +116,7 @@ static int mtk_rtc_set_time(struct device *dev, struct rtc_time *tm) > int ret; > u16 data[RTC_OFFSET_COUNT]; > > + tm->tm_year -= RTC_MIN_YEAR_OFFSET; > tm->tm_mon++; > tm->tm_wday++; > > @@ -167,6 +174,7 @@ static int mtk_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) > tm->tm_mon = data[RTC_OFFSET_MTH] & RTC_AL_MTH_MASK; > tm->tm_year = data[RTC_OFFSET_YEAR] & RTC_AL_YEA_MASK; > > + tm->tm_year += RTC_MIN_YEAR_OFFSET; > tm->tm_mon--; > > return 0; > @@ -182,6 +190,7 @@ static int mtk_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) > int ret; > u16 data[RTC_OFFSET_COUNT]; > > + tm->tm_year -= RTC_MIN_YEAR_OFFSET; > tm->tm_mon++; > > mutex_lock(&rtc->lock); > > -- > 2.25.1 > -- Alexandre Belloni, co-owner and COO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com