commit 00a39d8652 upstream.
cmos_interrupt() can be called in a non-interrupt context, such as in
an ACPI event handler (which runs in an interrupt thread). Therefore,
usage of spin_lock(&rtc_lock) is insecure. Use spin_lock_irqsave() /
spin_unlock_irqrestore() instead.
Before a misguided
commit 6950d046eb ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ")
the cmos_interrupt() function used spin_lock_irqsave(). That commit
changed it to spin_lock() and broke locking, which was partially fixed in
commit 13be2efc39 ("rtc: cmos: Disable irq around direct invocation of cmos_interrupt()")
That second commit did not take account of the ACPI fixed event handler
pathway, however. It introduced local_irq_disable() workarounds in
cmos_check_wkalrm(), which can cause problems on PREEMPT_RT kernels
and are now unnecessary.
Add an explicit comment so that this change will not be reverted by
mistake.
Cc: stable@vger.kernel.org
Fixes: 6950d046eb ("rtc: cmos: Replace spin_lock_irqsave with spin_lock in hard IRQ")
Signed-off-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Reported-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Closes: https://lore.kernel.org/all/aDtJ92foPUYmGheF@debian.local/
Link: https://lore.kernel.org/r/20250607210608.14835-1-mat.jonczyk@o2.pl
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5af9f1fa57 ]
When an application sets and enables an alarm on Loongson RTC devices,
the alarm notification fails to propagate to userspace because the
ACPI event handler omits calling rtc_update_irq().
As a result, processes waiting via select() or poll() on RTC device
files fail to receive alarm notifications.
The ACPI interrupt is also triggered multiple times. In loongson_rtc_handler,
we need to clear TOY_MATCH0_REG to resolve this issue.
Fixes: 09471d8f5b ("rtc: loongson: clear TOY_MATCH0_REG in loongson_rtc_isr()")
Fixes: 1b733a9ebc ("rtc: Add rtc driver for the Loongson family chips")
Signed-off-by: Liu Dalin <liudalin@kylinsec.com.cn>
Reviewed-by: Binbin Zhou <zhoubinbin@loongson.cn>
Link: https://lore.kernel.org/r/20250509084416.7979-1-liudalin@kylinsec.com.cn
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 8f2efdbc30 ]
The DT bindings for this driver define the interrupts in the order as
they are numbered in the interrupt controller. The old platform_data,
however, listed them in a different order. So, for DT based platforms,
they are mixed up. Assign them specifically for DT, so we can keep the
bindings stable. After the fix, 'rtctest' passes again on the Renesas
Genmai board (RZ-A1 / R7S72100).
Fixes: dab5aec64b ("rtc: sh: add support for rza series")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20250227134256.9167-11-wsa+renesas@sang-engineering.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit fe9f5f96cf upstream.
The comparison
rtc->start_secs > rtc->range_max
has a signed left-hand side and an unsigned right-hand side.
So the comparison might become true for negative start_secs which is
interpreted as a (possibly very large) positive value.
As a negative value can never be bigger than an unsigned value
the correct representation of the (mathematical) comparison
rtc->start_secs > rtc->range_max
in C is:
rtc->start_secs >= 0 && rtc->start_secs > rtc->range_max
Use that to fix the offset calculation currently used in the
rtc-mt6397 driver.
Fixes: 989515647e ("rtc: Add one offset seconds to expand RTC range")
Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250428-enable-rtc-v4-2-2b2f7e3f9349@baylibre.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7df4cfef8b upstream.
Conversion of dates before 1970 is still relevant today because these
dates are reused on some hardwares to store dates bigger than the
maximal date that is representable in the device's native format.
This prominently and very soon affects the hardware covered by the
rtc-mt6397 driver that can only natively store dates in the interval
1900-01-01 up to 2027-12-31. So to store the date 2028-01-01 00:00:00
to such a device, rtc_time64_to_tm() must do the right thing for
time=-2208988800.
Signed-off-by: Alexandre Mergnat <amergnat@baylibre.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/20250428-enable-rtc-v4-1-2b2f7e3f9349@baylibre.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2b7cbd9849 ]
Power-on Reset has a documented issue in PCF85063, refer to its datasheet,
section "Software reset":
"There is a low probability that some devices will have corruption of the
registers after the automatic power-on reset if the device is powered up
with a residual VDD level. It is required that the VDD starts at zero volts
at power up or upon power cycling to ensure that there is no corruption of
the registers. If this is not possible, a reset must be initiated after
power-up (i.e. when power is stable) with the software reset command"
Trigger SW reset if there is an indication that POR has failed.
Link: https://www.nxp.com/docs/en/data-sheet/PCF85063A.pdf
Signed-off-by: Lukas Stockmann <lukas.stockmann@siemens.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Link: https://lore.kernel.org/r/20250120093451.30778-1-alexander.sverdlin@siemens.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 09471d8f5b ]
The TOY_MATCH0_REG should be cleared to 0 in the RTC interrupt handler,
otherwise the interrupt cannot be cleared, which will cause the
loongson_rtc_isr() to be triggered multiple times.
The previous code cleared TOY_MATCH0_REG in the loongson_rtc_handler(),
which is an ACPI interrupt. This did not prevent loongson_rtc_isr()
from being triggered multiple times.
This commit moves the clearing of TOY_MATCH0_REG to the
loongson_rtc_isr() to ensure that the interrupt is properly cleared.
Fixes: 1b733a9ebc ("rtc: Add rtc driver for the Loongson family chips")
Signed-off-by: Ming Wang <wangming01@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Keguang Zhang <keguang.zhang@gmail.com> # on LS1B
Tested-by: Keguang Zhang <keguang.zhang@gmail.com>
Link: https://lore.kernel.org/r/20241205114307.1891418-1-wangming01@loongson.cn
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 09c4a61015 ]
The problem is this multiply in tps6594_rtc_set_offset()
tmp = offset * TICKS_PER_HOUR;
The "tmp" variable is an s64 but "offset" is a long in the
(-277774)-277774 range. On 32bit systems a long can hold numbers up to
approximately two billion. The number of TICKS_PER_HOUR is really large,
(32768 * 3600) or roughly a hundred million. When you start multiplying
by a hundred million it doesn't take long to overflow the two billion
mark.
Probably the safest way to fix this is to change the type of
TICKS_PER_HOUR to long long because it's such a large number.
Fixes: 9f67c1e639 ("rtc: tps6594: Add driver for TPS6594 RTC")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/1074175e-5ecb-4e3d-b721-347d794caa90@stanley.mountain
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0a6efab33e ]
On my device reading entirety of /sys/devices/pnp0/00:03/cmos_nvram0/nvmem
takes about 9 msec during which time interrupts are off on the CPU that
does the read and the thread that performs the read can not be migrated
or preempted by another higher priority thread (RT or not).
Allow readers and writers be preempted by taking and releasing rtc_lock
spinlock for each individual byte read or written rather than once per
read/write request.
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Mateusz Jończyk <mat.jonczyk@o2.pl>
Link: https://lore.kernel.org/r/Zxv8QWR21AV4ztC5@google.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e0779a0dcf ]
The undervoltage flags reported by the RTC are useful to know if the
time and date are reliable after a reboot. Although the threshold VLOW1
indicates that the thermometer has been shutdown and time compensation
is off, it doesn't mean that the temperature readout is currently
impossible.
As the system is running, the RTC voltage is now fully established and
we can read the temperature.
Fixes: 67075b63cc ("rtc: add AB-RTCMC-32.768kHz-EOZ9 RTC support")
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://lore.kernel.org/r/20241122101031.68916-3-maxime.chevallier@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit e8ba8a2bc4 ]
If the __rtc_read_time call fails,, the struct rtc_time tm; may contain
uninitialized data, or an illegal date/time read from the RTC hardware.
When calling rtc_tm_to_ktime later, the result may be a very large value
(possibly KTIME_MAX). If there are periodic timers in rtc->timerqueue,
they will continually expire, may causing kernel softlockup.
Fixes: 6610e0893b ("RTC: Rework RTC code to use timerqueue for events")
Signed-off-by: Yongliang Gao <leonylgao@tencent.com>
Acked-by: Jingqun Li <jingqunli@tencent.com>
Link: https://lore.kernel.org/r/20241011043153.3788112-1-leonylgao@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
asm/unaligned.h is always an include of asm-generic/unaligned.h;
might as well move that thing to linux/unaligned.h and include
that - there's nothing arch-specific in that header.
auto-generated by the following:
for i in `git grep -l -w asm/unaligned.h`; do
sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i
done
for i in `git grep -l -w asm-generic/unaligned.h`; do
sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i
done
git mv include/asm-generic/unaligned.h include/linux/unaligned.h
git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h
sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild
sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
no_llseek had been defined to NULL two years ago, in commit 868941b144
("fs: remove no_llseek")
To quote that commit,
At -rc1 we'll need do a mechanical removal of no_llseek -
git grep -l -w no_llseek | grep -v porting.rst | while read i; do
sed -i '/\<no_llseek\>/d' $i
done
would do it.
Unfortunately, that hadn't been done. Linus, could you do that now, so
that we could finally put that thing to rest? All instances are of the
form
.llseek = no_llseek,
so it's obviously safe.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull RTC updates from Alexandre Belloni:
"More conversions of DT bindings to yaml. There is one new driver, for
the DFRobot SD2405AL and support for important features of the stm32
RTC. Summary:
New driver:
- DFRobot SD2405AL
Drivers:
- stm32: add alarm A out and LSCO support
- sun6i: disable automatic clock input switching
- m48t59: set range"
* tag 'rtc-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
rtc: rc5t619: use proper module tables
rtc: m48t59: set range
dt-bindings: rtc: microcrystal,rv3028: add #clock-cells property
rtc: m48t59: Remove division condition with direct comparison
rtc: at91sam9: fix OF node leak in probe() error path
rtc: sun6i: disable automatic clock input switching
dt-bindings: rtc: Drop non-trivial duplicate compatibles
dt-bindings: vendor-prefixes: Add DFRobot.
dt-bindings: rtc: Add support for SD2405AL.
rtc: Add driver for SD2405AL
rtc: s35390a: Drop vendorless compatible string from match table
rtc: twl: convert comma to semicolon
dt-bindings: rtc: sprd,sc2731-rtc: convert to YAML
rtc: stm32: add alarm A out feature
rtc: stm32: add Low Speed Clock Output (LSCO) support
rtc: stm32: add pinctrl and pinmux interfaces
dt-bindings: rtc: stm32: describe pinmux nodes
The V3(s) will detect a valid external low frequency clock and if it is
not present will automatically switch to the internal one. This might
hide bugs and (hardware) configuration errors. It's even worse because
the internal RTC runs significantly slower (32.000Hz vs 32.768Hz).
Fortunately for us, the V3(s) has an (undocumented) bypass of this
switching and the driver already supports it by setting the
.has_auto_swt flag.
Signed-off-by: Michael Walle <mwalle@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20240730194905.2587202-1-mwalle@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
STM32 RTC can pulse some SOC pins when an RTC alarm expires.
This patch adds this functionality for alarm A. The pulse can out on three
pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP (PC13, PB2, PI8 on stm32mp15)
(PC13, PB2, PI1 on stm32mp13) (PC13, PF4/PF6, PI8 on stm32mp25).
This patch only adds the functionality for devices which are using
st,stm32mp1-rtc and st,stm32mp25-rtc compatible.
Add "alarm-a" in pinmux functions.
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20240722160022.454226-5-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
RTC is able to output on a pin the "LSE" internal clock.
STM32 RTC is now registered as a clock provider.
It provides rtc_lsco clock, that means RTC_LSCO is output on either
RTC_OUT1 or RTC_OUT2_RMP, depending on pinmux DT property.
The clock is marked as CLK_IGNORE_UNUSED and CLK_IS_CRITICAL because
RTC_LSCO can be early required by devices needed it to init.
Add LSCO in pinmux functions.
Add "stm32_rtc_clean_outs" to disable LSCO. As RTC is part of "backup"
power domain, it is not reset during shutdown or reboot. So force LSCO
disable at probe.
Co-developed-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20240722160022.454226-4-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
These drivers don't use the driver_data member of struct i2c_device_id,
so don't explicitly initialize this member.
This prepares putting driver_data in an anonymous union which requires
either no initialization or named designators. But it's also a nice
cleanup on its own.
While add it, also remove a comma after the sentinel entry in
rtc-hym8563.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20240515194336.58342-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
`rtc_add_offset()` is called by `__rtc_read_time()`
and `__rtc_read_alarm()` to add the RTC's offset to
the raw read-outs from the device drivers. However,
in the latter case, a fix-up algorithm is run if
the RTC device does not report a full `struct rtc_time`
alarm value. In that case, the offset was forgot to be
added.
Fixes: fd6792bb02 ("rtc: fix alarm read and set offset")
Signed-off-by: Csókás, Bence <csokas.bence@prolan.hu>
Link: https://lore.kernel.org/r/20240619140451.2800578-1-csokas.bence@prolan.hu
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
On x86, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/lib_test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-goldfish.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-omap.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-rc5t583.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-tps65910.o
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/rtc/rtc-twl.o
Add the missing invocation of the MODULE_DESCRIPTION() macro to all
files which have a MODULE_LICENSE(). This includes rtc-mpc5121.c,
which does not produce a warning with the x86 allmodconfig since it is
not built for x86, but it may cause this warning with Freescale PPC
configurations.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Link: https://lore.kernel.org/r/20240608-md-drivers-rtc-v1-1-5f44222adfae@quicinc.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Read callbacks registered with nvmem core expect 0 to be returned on
success and a negative value to be returned on failure.
abx80x_nvmem_xfer() on read calls i2c_smbus_read_i2c_block_data() which
returns the number of bytes read on success as per its api description,
this return value is handled as an error and returned to nvmem even on
success.
Fix to handle all possible values that would be returned by
i2c_smbus_read_i2c_block_data().
Fixes: e90ff8ede7 ("rtc: abx80x: Add nvmem support")
Cc: stable@vger.kernel.org
Signed-off-by: Joy Chakraborty <joychakr@google.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Sean Anderson <sean.anderson@seco.com>
Link: https://lore.kernel.org/r/20240613120750.1455209-1-joychakr@google.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
