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rtc: da9063: avoid writing undefined data to rtc

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driver did

| static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
| {
|  	const struct da9063_compatible_rtc_regmap *config = rtc->config;
|
| 	data[RTC_SEC] &= ~config->rtc_count_sec_mask;
| 	data[RTC_SEC] |= tm->tm_sec & config->rtc_count_sec_mask;
| ...
| }
| ...
| static int da9063_rtc_set_time(struct device *dev, struct rtc_time *tm)
| {
|       ...
|	u8 data[RTC_DATA_LEN];
|	int ret;
|
|	da9063_tm_to_data(tm, data, rtc);

which means that some bits of stack content (in 'data[]') was masked out
and written to the RTC.

Because da9063_tm_to_data() is used only by da9063_rtc_set_time() and
da9063_rtc_set_alarm(), we can write fields directly.

Signed-off-by: Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Tested-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
This commit is contained in:
Enrico Scholz 2015-11-27 13:02:55 +01:00 committed by Alexandre Belloni
parent 4d833d6013
commit 2ad2c17480
1 changed files with 6 additions and 17 deletions
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23
drivers/rtc/rtc-da9063.c
View File

@ -191,24 +191,13 @@ static void da9063_tm_to_data(struct rtc_time *tm, u8 *data,
{ {
const struct da9063_compatible_rtc_regmap *config = rtc->config; const struct da9063_compatible_rtc_regmap *config = rtc->config;
data[RTC_SEC] &= ~config->rtc_count_sec_mask; data[RTC_SEC] = tm->tm_sec & config->rtc_count_sec_mask;
data[RTC_SEC] |= tm->tm_sec & config->rtc_count_sec_mask; data[RTC_MIN] = tm->tm_min & config->rtc_count_min_mask;
data[RTC_HOUR] = tm->tm_hour & config->rtc_count_hour_mask;
data[RTC_MIN] &= ~config->rtc_count_min_mask; data[RTC_DAY] = tm->tm_mday & config->rtc_count_day_mask;
data[RTC_MIN] |= tm->tm_min & config->rtc_count_min_mask; data[RTC_MONTH] = MONTHS_TO_DA9063(tm->tm_mon) &
data[RTC_HOUR] &= ~config->rtc_count_hour_mask;
data[RTC_HOUR] |= tm->tm_hour & config->rtc_count_hour_mask;
data[RTC_DAY] &= ~config->rtc_count_day_mask;
data[RTC_DAY] |= tm->tm_mday & config->rtc_count_day_mask;
data[RTC_MONTH] &= ~config->rtc_count_month_mask;
data[RTC_MONTH] |= MONTHS_TO_DA9063(tm->tm_mon) &
config->rtc_count_month_mask; config->rtc_count_month_mask;
data[RTC_YEAR] = YEARS_TO_DA9063(tm->tm_year) &
data[RTC_YEAR] &= ~config->rtc_count_year_mask;
data[RTC_YEAR] |= YEARS_TO_DA9063(tm->tm_year) &
config->rtc_count_year_mask; config->rtc_count_year_mask;
} }