diff options
| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2026-04-22 18:26:49 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2026-04-27 22:57:09 +0300 |
| commit | e0d219010477fb19d23b60970b2c03fe5985717c (patch) | |
| tree | 6ff70bb0201337b664a2dc4ec02d6d90d6a9ef85 | |
| parent | 77dd14ab1b575328745644136ba758d394e10fbc (diff) | |
| download | linux-e0d219010477fb19d23b60970b2c03fe5985717c.tar.xz | |
ACPI: TAD: RTC: Refine timer value computations and checks
Since rtc_tm_to_ktime() may overflow for large RTC time values and
full second granularity is sufficient in timer value computations
in acpi_tad_rtc_set_alarm() and acpi_tad_rtc_read_alarm(), use
rtc_tm_to_time64() instead of that function, which also allows the
computations to be simplified.
Moreover, U32_MAX is a special "timer disabled" value, so make
acpi_tad_rtc_set_alarm() reject it when attempting to program the
alarm timers.
Fixes: 7572dcabe38d ("ACPI: TAD: Add alarm support to the RTC class device interface")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://patch.msgid.link/3414608.aeNJFYEL58@rafael.j.wysocki
| -rw-r--r-- | drivers/acpi/acpi_tad.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/drivers/acpi/acpi_tad.c b/drivers/acpi/acpi_tad.c index 2aaef50a2d0f..bdf8695c00f3 100644 --- a/drivers/acpi/acpi_tad.c +++ b/drivers/acpi/acpi_tad.c @@ -680,9 +680,8 @@ static int acpi_tad_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *t) acpi_tad_rt_to_tm(&rt, &tm_now); - value = ktime_divns(ktime_sub(rtc_tm_to_ktime(t->time), - rtc_tm_to_ktime(tm_now)), NSEC_PER_SEC); - if (value <= 0 || value > U32_MAX) + value = rtc_tm_to_time64(&t->time) - rtc_tm_to_time64(&tm_now); + if (value <= 0 || value >= U32_MAX) return -EINVAL; } @@ -745,8 +744,7 @@ static int acpi_tad_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *t) if (retval != ACPI_TAD_WAKE_DISABLED) { t->enabled = 1; - t->time = rtc_ktime_to_tm(ktime_add_ns(rtc_tm_to_ktime(tm_now), - (u64)retval * NSEC_PER_SEC)); + rtc_time64_to_tm(rtc_tm_to_time64(&tm_now) + retval, &t->time); } else { t->enabled = 0; t->time = tm_now; |