From 6a2b342228b98432a585c83d59ed6aa0620be7c4 Mon Sep 17 00:00:00 2001 From: Alexander Shiyan Date: Thu, 3 Apr 2014 14:50:01 -0700 Subject: rtc: mc13xxx: make rtc_read_time() more readable MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove unnecessary locks when reading the time and make the read operation until the values of day matched between reading the seconds, it will make the mc13xxx_rtc_read_time() procedure more readable. Additionally, patch introduced a "seconds in a day" definition. Signed-off-by: Alexander Shiyan Cc: Uwe Kleine-König Cc: Sascha Hauer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-mc13xxx.c | 59 ++++++++++++++++++----------------------------- 1 file changed, 23 insertions(+), 36 deletions(-) (limited to 'drivers') diff --git a/drivers/rtc/rtc-mc13xxx.c b/drivers/rtc/rtc-mc13xxx.c index 7b39852eb54..9b1a77eb91a 100644 --- a/drivers/rtc/rtc-mc13xxx.c +++ b/drivers/rtc/rtc-mc13xxx.c @@ -23,6 +23,8 @@ #define MC13XXX_RTCDAY 22 #define MC13XXX_RTCDAYA 23 +#define SEC_PER_DAY (24 * 60 * 60) + struct mc13xxx_rtc { struct rtc_device *rtc; struct mc13xxx *mc13xxx; @@ -61,42 +63,27 @@ static int mc13xxx_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct mc13xxx_rtc *priv = dev_get_drvdata(dev); unsigned int seconds, days1, days2; - unsigned long s1970; - int ret; if (!priv->valid) return -ENODATA; - mc13xxx_lock(priv->mc13xxx); + do { + int ret; - ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days1); - if (unlikely(ret)) - goto out; - - ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds); - if (unlikely(ret)) - goto out; - - ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2); -out: - mc13xxx_unlock(priv->mc13xxx); - - if (ret) - return ret; - - if (days2 == days1 + 1) { - if (seconds >= 86400 / 2) - days2 = days1; - else - days1 = days2; - } + ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days1); + if (ret) + return ret; - if (days1 != days2) - return -EIO; + ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds); + if (ret) + return ret; - s1970 = days1 * 86400 + seconds; + ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2); + if (ret) + return ret; + } while (days1 != days2); - rtc_time_to_tm(s1970, tm); + rtc_time_to_tm(days1 * SEC_PER_DAY + seconds, tm); return rtc_valid_tm(tm); } @@ -108,8 +95,8 @@ static int mc13xxx_rtc_set_mmss(struct device *dev, unsigned long secs) unsigned int alarmseconds; int ret; - seconds = secs % 86400; - days = secs / 86400; + seconds = secs % SEC_PER_DAY; + days = secs / SEC_PER_DAY; mc13xxx_lock(priv->mc13xxx); @@ -121,7 +108,7 @@ static int mc13xxx_rtc_set_mmss(struct device *dev, unsigned long secs) if (unlikely(ret)) goto out; - if (alarmseconds < 86400) { + if (alarmseconds < SEC_PER_DAY) { ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, 0x1ffff); if (unlikely(ret)) @@ -145,7 +132,7 @@ static int mc13xxx_rtc_set_mmss(struct device *dev, unsigned long secs) goto out; /* restore alarm */ - if (alarmseconds < 86400) { + if (alarmseconds < SEC_PER_DAY) { ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCTODA, alarmseconds); if (unlikely(ret)) @@ -181,7 +168,7 @@ static int mc13xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTODA, &seconds); if (unlikely(ret)) goto out; - if (seconds >= 86400) { + if (seconds >= SEC_PER_DAY) { ret = -ENODATA; goto out; } @@ -202,7 +189,7 @@ out: alarm->enabled = enabled; alarm->pending = pending; - s1970 = days * 86400 + seconds; + s1970 = days * SEC_PER_DAY + seconds; rtc_time_to_tm(s1970, &alarm->time); dev_dbg(dev, "%s: %lu\n", __func__, s1970); @@ -240,8 +227,8 @@ static int mc13xxx_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) if (unlikely(ret)) goto out; - seconds = s1970 % 86400; - days = s1970 / 86400; + seconds = s1970 % SEC_PER_DAY; + days = s1970 / SEC_PER_DAY; ret = mc13xxx_reg_write(priv->mc13xxx, MC13XXX_RTCDAYA, days); if (unlikely(ret)) -- cgit v1.2.3-70-g09d2