linux-kernel - Re: [PATCH v6 5/6] rtc: mt6397: fix alarm register overwrite

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Message-ID: <1576030774.24528.2.camel@mtksdaap41>
Date:   Wed, 11 Dec 2019 10:19:34 +0800
From:   Hsin-hsiung Wang <hsin-hsiung.wang@...iatek.com>
To:     Alexandre Belloni <alexandre.belloni@...tlin.com>
CC:     Lee Jones <lee.jones@...aro.org>, Rob Herring <robh+dt@...nel.org>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Mark Rutland <mark.rutland@....com>,
        Eddie Huang <eddie.huang@...iatek.com>,
        Sean Wang <sean.wang@...iatek.com>,
        Alessandro Zummo <a.zummo@...ertech.it>,
        <devicetree@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-mediatek@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>, <linux-rtc@...r.kernel.org>,
        <srv_heupstream@...iatek.com>, Ran Bi <ran.bi@...iatek.com>
Subject: Re: [PATCH v6 5/6] rtc: mt6397: fix alarm register overwrite

Hi,

On Tue, 2019-12-10 at 17:41 +0100, Alexandre Belloni wrote:
> Hi,
> 
> On 06/12/2019 21:33:02+0800, Hsin-Hsiung Wang wrote:
> > From: Ran Bi <ran.bi@...iatek.com>
> > 
> > Alarm registers high byte was reserved for other functions.
> > This add mask in alarm registers operation functions.
> > This also fix error condition in interrupt handler.
> > 
> > Fixes: fc2979118f3f ("rtc: mediatek: Add MT6397 RTC driver")
> > 
> > Signed-off-by: Ran Bi <ran.bi@...iatek.com>
> > Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@...iatek.com>
> > ---
> >  drivers/rtc/rtc-mt6397.c | 47 +++++++++++++++++++++++++++++++++--------------
> >  1 file changed, 33 insertions(+), 14 deletions(-)
> > 
> 
> Can you rebase that one on top of v5.5-rc1 soon? I'll include it in -fixes.
> 
Sure, I will send the next version later.

> > diff --git a/drivers/rtc/rtc-mt6397.c b/drivers/rtc/rtc-mt6397.c
> > index 704229e..b216bdc 100644
> > --- a/drivers/rtc/rtc-mt6397.c
> > +++ b/drivers/rtc/rtc-mt6397.c
> > @@ -47,6 +47,14 @@
> >  
> >  #define RTC_AL_SEC		0x0018
> >  
> > +#define RTC_AL_SEC_MASK		0x003f
> > +#define RTC_AL_MIN_MASK		0x003f
> > +#define RTC_AL_HOU_MASK		0x001f
> > +#define RTC_AL_DOM_MASK		0x001f
> > +#define RTC_AL_DOW_MASK		0x0007
> > +#define RTC_AL_MTH_MASK		0x000f
> > +#define RTC_AL_YEA_MASK		0x007f
> > +
> >  #define RTC_PDN2		0x002e
> >  #define RTC_PDN2_PWRON_ALARM	BIT(4)
> >  
> > @@ -103,7 +111,7 @@ static irqreturn_t mtk_rtc_irq_handler_thread(int irq, void *data)
> >  		irqen = irqsta & ~RTC_IRQ_EN_AL;
> >  		mutex_lock(&rtc->lock);
> >  		if (regmap_write(rtc->regmap, rtc->addr_base + RTC_IRQ_EN,
> > -				 irqen) < 0)
> > +				 irqen) == 0)
> >  			mtk_rtc_write_trigger(rtc);
> >  		mutex_unlock(&rtc->lock);
> >  
> > @@ -225,12 +233,12 @@ static int mtk_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm)
> >  	alm->pending = !!(pdn2 & RTC_PDN2_PWRON_ALARM);
> >  	mutex_unlock(&rtc->lock);
> >  
> > -	tm->tm_sec = data[RTC_OFFSET_SEC];
> > -	tm->tm_min = data[RTC_OFFSET_MIN];
> > -	tm->tm_hour = data[RTC_OFFSET_HOUR];
> > -	tm->tm_mday = data[RTC_OFFSET_DOM];
> > -	tm->tm_mon = data[RTC_OFFSET_MTH];
> > -	tm->tm_year = data[RTC_OFFSET_YEAR];
> > +	tm->tm_sec = data[RTC_OFFSET_SEC] & RTC_AL_SEC_MASK;
> > +	tm->tm_min = data[RTC_OFFSET_MIN] & RTC_AL_MIN_MASK;
> > +	tm->tm_hour = data[RTC_OFFSET_HOUR] & RTC_AL_HOU_MASK;
> > +	tm->tm_mday = data[RTC_OFFSET_DOM] & RTC_AL_DOM_MASK;
> > +	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--;
> > @@ -251,14 +259,25 @@ static int mtk_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
> >  	tm->tm_year -= RTC_MIN_YEAR_OFFSET;
> >  	tm->tm_mon++;
> >  
> > -	data[RTC_OFFSET_SEC] = tm->tm_sec;
> > -	data[RTC_OFFSET_MIN] = tm->tm_min;
> > -	data[RTC_OFFSET_HOUR] = tm->tm_hour;
> > -	data[RTC_OFFSET_DOM] = tm->tm_mday;
> > -	data[RTC_OFFSET_MTH] = tm->tm_mon;
> > -	data[RTC_OFFSET_YEAR] = tm->tm_year;
> > -
> >  	mutex_lock(&rtc->lock);
> > +	ret = regmap_bulk_read(rtc->regmap, rtc->addr_base + RTC_AL_SEC,
> > +			       data, RTC_OFFSET_COUNT);
> > +	if (ret < 0)
> > +		goto exit;
> > +
> > +	data[RTC_OFFSET_SEC] = ((data[RTC_OFFSET_SEC] & ~(RTC_AL_SEC_MASK)) |
> > +				(tm->tm_sec & RTC_AL_SEC_MASK));
> > +	data[RTC_OFFSET_MIN] = ((data[RTC_OFFSET_MIN] & ~(RTC_AL_MIN_MASK)) |
> > +				(tm->tm_min & RTC_AL_MIN_MASK));
> > +	data[RTC_OFFSET_HOUR] = ((data[RTC_OFFSET_HOUR] & ~(RTC_AL_HOU_MASK)) |
> > +				(tm->tm_hour & RTC_AL_HOU_MASK));
> > +	data[RTC_OFFSET_DOM] = ((data[RTC_OFFSET_DOM] & ~(RTC_AL_DOM_MASK)) |
> > +				(tm->tm_mday & RTC_AL_DOM_MASK));
> > +	data[RTC_OFFSET_MTH] = ((data[RTC_OFFSET_MTH] & ~(RTC_AL_MTH_MASK)) |
> > +				(tm->tm_mon & RTC_AL_MTH_MASK));
> > +	data[RTC_OFFSET_YEAR] = ((data[RTC_OFFSET_YEAR] & ~(RTC_AL_YEA_MASK)) |
> > +				(tm->tm_year & RTC_AL_YEA_MASK));
> > +
> >  	if (alm->enabled) {
> >  		ret = regmap_bulk_write(rtc->regmap,
> >  					rtc->addr_base + RTC_AL_SEC,
> > -- 
> > 2.6.4
>