kpriv/linux-hardened
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

rtc: mc13xxx: make rtc_read_time() more readable

Browse source 
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 <shc_work@mail.ru>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Sascha Hauer <kernel@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alexander Shiyan 2014-04-03 14:50:01 -07:00 committed by Linus Torvalds
parent 12de362108
commit 6a2b342228
1 changed files with 23 additions and 36 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

59
drivers/rtc/rtc-mc13xxx.c
View file

@ -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_RTCDAY, &days1);
if (ret)
return ret;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds);
if (unlikely(ret))
goto out;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCTOD, &seconds);
if (ret)
return ret;
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2);
out:
mc13xxx_unlock(priv->mc13xxx);
ret = mc13xxx_reg_read(priv->mc13xxx, MC13XXX_RTCDAY, &days2);
if (ret)
return ret;
} while (days1 != days2);
if (ret)
return ret;
if (days2 == days1 + 1) {
if (seconds >= 86400 / 2)
days2 = days1;
else
days1 = days2;
}
if (days1 != days2)
return -EIO;
s1970 = days1 * 86400 + seconds;
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))