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| author | Heinrich Schuchardt <xypron.glpk@gmx.de> | 2016-05-22 00:18:55 +0200 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@free-electrons.com> | 2016-06-04 15:46:08 +0200 |
| commit | c5776dec8f2a90a0aa9e197c2900f68fda8dd978 (patch) | |
| tree | 7c194e5a9a008ab147e7c926e81dfd0fca9d6dd8 /drivers/rtc | |
| parent | 2b2f5ff00f63847d95adad6289bd8b05f5983dd5 (diff) | |
| download | linux-c5776dec8f2a90a0aa9e197c2900f68fda8dd978.tar.gz linux-c5776dec8f2a90a0aa9e197c2900f68fda8dd978.tar.bz2 linux-c5776dec8f2a90a0aa9e197c2900f68fda8dd978.zip | |
rtc: ds1685: correct day of month checking
The day of month is checked in ds1685_rtc_read_alarm
and ds1685_rtc_set_alarm.
Multiple errors exist in the day of month check.
Operator ! has a higher priority than &&.
(!(mday >= 1) && (mday <= 31)) is false for mday == 32.
When verifying the day of month the binary and the BCD mode
have to be considered.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Diffstat (limited to 'drivers/rtc')
| -rw-r--r-- | drivers/rtc/rtc-ds1685.c | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/drivers/rtc/rtc-ds1685.c b/drivers/rtc/rtc-ds1685.c index b3ce3c652fcd..68197042feb7 100644 --- a/drivers/rtc/rtc-ds1685.c +++ b/drivers/rtc/rtc-ds1685.c @@ -103,6 +103,26 @@ ds1685_rtc_bin2bcd(struct ds1685_priv *rtc, u8 val, u8 bin_mask, u8 bcd_mask) } /** + * s1685_rtc_check_mday - check validity of the day of month. + * @rtc: pointer to the ds1685 rtc structure. + * @mday: day of month. + * + * Returns -EDOM if the day of month is not within 1..31 range. + */ +static inline int +ds1685_rtc_check_mday(struct ds1685_priv *rtc, u8 mday) +{ + if (rtc->bcd_mode) { + if (mday < 0x01 || mday > 0x31 || (mday & 0x0f) > 0x09) + return -EDOM; + } else { + if (mday < 1 || mday > 31) + return -EDOM; + } + return 0; +} + +/** * ds1685_rtc_switch_to_bank0 - switch the rtc to bank 0. * @rtc: pointer to the ds1685 rtc structure. */ @@ -377,6 +397,7 @@ ds1685_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) struct platform_device *pdev = to_platform_device(dev); struct ds1685_priv *rtc = platform_get_drvdata(pdev); u8 seconds, minutes, hours, mday, ctrlb, ctrlc; + int ret; /* Fetch the alarm info from the RTC alarm registers. */ ds1685_rtc_begin_data_access(rtc); @@ -388,9 +409,10 @@ ds1685_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) ctrlc = rtc->read(rtc, RTC_CTRL_C); ds1685_rtc_end_data_access(rtc); - /* Check month date. */ - if (!(mday >= 1) && (mday <= 31)) - return -EDOM; + /* Check the month date for validity. */ + ret = ds1685_rtc_check_mday(rtc, mday); + if (ret) + return ret; /* * Check the three alarm bytes. @@ -445,6 +467,7 @@ ds1685_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) struct platform_device *pdev = to_platform_device(dev); struct ds1685_priv *rtc = platform_get_drvdata(pdev); u8 ctrlb, seconds, minutes, hours, mday; + int ret; /* Fetch the alarm info and convert to BCD. */ seconds = ds1685_rtc_bin2bcd(rtc, alrm->time.tm_sec, @@ -461,8 +484,9 @@ ds1685_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) RTC_MDAY_BCD_MASK); /* Check the month date for validity. */ - if (!(mday >= 1) && (mday <= 31)) - return -EDOM; + ret = ds1685_rtc_check_mday(rtc, mday); + if (ret) + return ret; /* * Check the three alarm bytes. |