When the alarm is not enabled, it may never have been set and so we can't
expect it to be valid. This will prevent the apparition of boot messages
like this one:
rtc rtc0: invalid alarm value: 2023-7-8 45:85:85
Link: https://lore.kernel.org/r/20230827221532.543353-1-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
When wakeup-source is set in the devicetree, set up the device for
using the output as interrupt instead of clock. This is similar to
how other RTC devices handle this.
This allows the clock chip to turn on the board when wired to do
so in hardware.
Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Link: https://lore.kernel.org/r/20230821072013.7072-1-mike.looijmans@topic.nl
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
RZN1 only supports alarms up to one week in the future.
Report the limit to the RTC core and use the reported limit
to validate the requested alarm time when setting it.
Cc: Brian Norris <briannorris@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/r/20230817225537.4053865-8-linux@roeck-us.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
DS1305 only supports alarms up to 24 hours in the future.
Report the limit to the RTC core, and use the reported limit
to validate the requested alarm time when setting it.
If the alarm is too large when trying to set an alarm, return -ERANGE
instead of -EDOM to align with error codes returned by other rtc drivers.
Cc: Brian Norris <briannorris@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230817225537.4053865-7-linux@roeck-us.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
tps6586x only supports alarms up to 16,383 seconds in the future.
Report the limit to the RTC core.
Cc: Brian Norris <briannorris@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230817225537.4053865-6-linux@roeck-us.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The alarm window supported by the cmos RTC depends on the chip
and its configuration. Report the limit to the RTC core.
Cc: Brian Norris <briannorris@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230817225537.4053865-5-linux@roeck-us.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The RTC on some older Chromebooks can only handle alarms less than
24 hours in the future. The only way to find out is to try to set
an alarm further in the future. If that fails, assume that the RTC
connected to the EC can only handle less than 24 hours of alarm
window, and report that value to the RTC core.
After that change, it is no longer necessary to limit the alarm time
when setting it. Report any excessive alarms to the caller instead.
Cc: Brian Norris <briannorris@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20230817225537.4053865-4-linux@roeck-us.net
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The XTOSCB bit is not bit 0, but xtosb_val is either 0 or 1. If it is 1,
test will never succeed. Fix this issue by using double negation.
While at it, remove unnecessary blank line from probe().
Reported-by: Pavel Machek <pavel@denx.de>
Closes: https://lore.kernel.org/all/ZN4BgzG2xmzOzdFZ@duo.ucw.cz/
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Pavel Machek <pavel@denx.de>
Link: https://lore.kernel.org/r/20230817161038.407960-1-biju.das.jz@bp.renesas.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
It is not possible for platform_get_irq() to return 0. Use the
return value from platform_get_irq().
And there is no need to call the dev_warn() function directly to print
a custom message when handling an error from platform_get_irq()
function as it is going to display an appropriate error message
in case of a failure.
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Link: https://lore.kernel.org/r/20230803080713.4061782-3-ruanjinjie@huawei.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
It is not possible for platform_get_irq() to return 0. Use the
return value from platform_get_irq().
Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Link: https://lore.kernel.org/r/20230803080713.4061782-2-ruanjinjie@huawei.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This keeps the IRQ enabled during system suspend, if the RTC's wakeup
source is enabled. Since the IRQ is not required to wake from shutdown,
continue to add the wakeup source even if registering the wakeirq fails.
See commit 029d3a6f2f ("rtc: da9063: add as wakeup source").
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20230717190937.1301509-1-samuel.holland@sifive.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
If PCF2127 device is absent from the I2C bus, or if there is a
communication problem, disabling POR0 may fail silently and we
still continue with probing the device. In that case, abort probe
operation.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230728171211.3016019-1-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This converts the DS2404 to use GPIO descriptors instead of
hard-coded global GPIO numbers.
The platform data can be deleted because there are no in-tree
users and it only contained GPIO numbers which are now
passed using descriptor tables (or device tree or ACPI).
The driver was rewritten to use a state container for the
device driver state (struct ds2404 *chip) and pass that
around instead of using a global singleton storage for the
GPIO handles.
When declaring GPIO descriptor tables or other hardware
descriptions for the RTC driver, implementers should take care
to flag the RESET line as active low, such as by using the
GPIOD_ACTIVE_LOW flag in the descriptor table.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230807-descriptors-rtc-v1-1-ce0f9187576e@linaro.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
After the switch to SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() and a subsequent
fix, stm32_rtc_{suspend,resume}() are unused when CONFIG_PM_SLEEP is not
set because SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() is a no-op in that
configuration:
drivers/rtc/rtc-stm32.c:904:12: error: 'stm32_rtc_resume' defined but not used [-Werror=unused-function]
904 | static int stm32_rtc_resume(struct device *dev)
| ^~~~~~~~~~~~~~~~
drivers/rtc/rtc-stm32.c:894:12: error: 'stm32_rtc_suspend' defined but not used [-Werror=unused-function]
894 | static int stm32_rtc_suspend(struct device *dev)
| ^~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
The non-"SET_" version of this macro, NOIRQ_SYSTEM_SLEEP_PM_OPS(), is
designed to handle this situation by only assigning the callbacks when
CONFIG_PM_SLEEP is set while allowing the functions to appear used to
the compiler. Switch to that macro to resolve the warnings. There is no
functional change with this, as SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() is
defined using NOIRQ_SYSTEM_SLEEP_PM_OPS() when CONFIG_PM_SLEEP is set.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20230815-rtc-stm32-unused-pm-funcs-v1-1-82eb8e02d903@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
'type' is an enum, thus cast of pointer on 64-bit compile test with W=1
causes:
rtc-rs5c372.c:829:19: error: cast to smaller integer type 'enum rtc_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230810103902.151145-4-krzysztof.kozlowski@linaro.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
'type' is an enum, thus cast of pointer on 64-bit compile test with W=1
causes:
rtc-jz4740.c:352:14: error: cast to smaller integer type 'enum jz4740_rtc_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230810103902.151145-3-krzysztof.kozlowski@linaro.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
'type' is an enum, thus cast of pointer on 64-bit compile test with W=1
causes:
rtc-rv8803.c:648:18: error: cast to smaller integer type 'enum rv8803_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230810103902.151145-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
'type' is an enum, thus cast of pointer on 64-bit compile test with W=1
causes:
rtc-ds1307.c:1747:18: error: cast to smaller integer type 'enum ds_type' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230810103902.151145-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
If device tree implies that the chip's IRQ/F_OUT pin is used as a
clock, expose that in the driver. For now, pretend it is a
fixed-rate (32kHz) clock; if other use cases appear the driver can be
updated to provide its own clk_ops etc.
When the clock output is not used on a given board, one can prolong
the battery life by ensuring that the FOx bits are 0. For the hardware
I'm currently working on, the RTC draws 1.2uA with the FOx bits at
their default 0001 value, dropping to 0.88uA when those bits are
cleared.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230615105826.411953-9-linux@rasmusvillemoes.dk
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Since the meaning of the SR_LBAT85 and SR_LBAT75 bits are different in
battery backup mode, they may very well be set after power on, and
stay set for up to a minute (i.e. until the battery detection in VDD
mode happens when the seconds counter hits 59). This would mean that
userspace doing a ioctl(RTC_VL_READ) early on could get a false
positive.
The battery level detection can also be triggered by explicitly
writing a 1 to the TSE bit in the BETA register. Do that once during
boot. Empirically, this does not immediately update the bits in
the status register (i.e., an immediate read of SR after this write
can still show stale values), but the update is done after a few
milliseconds, so certainly before the RTC device gets registered and
userspace has a chance of doing the ioctl() on this device.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230615105826.411953-7-linux@rasmusvillemoes.dk
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Hook up support for reading the values of the SR_LBAT85 and SR_LBAT75
bits. Translate the former to "battery low", and the latter to
"battery empty or not-present".
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230615105826.411953-6-linux@rasmusvillemoes.dk
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Implement support for using the values given in the
isil,battery-trip-levels-microvolt property to set appropriate values
in the VB85TP/VB75TP bits in the PWR_VBAT register.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230615105826.411953-5-linux@rasmusvillemoes.dk
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
There are multiple problems with this warning.
First of all, it triggers way too often, in fact nearly on every boot,
because the SR_LBAT85/SR_LBAT75 bits have another meaning when in
battery backup mode. Quoting from the data sheet:
LOW BATTERY INDICATOR 85% BIT (LBAT85)
In Normal Mode (VDD), this bit indicates when the battery level has
dropped below the pre-selected trip levels. [...] The LBAT85
detection happens automatically once every minute when seconds
register reaches 59.
In Battery Mode (VBAT), this bit indicates the device has entered
into battery mode by polling once every 10 minutes. The LBAT85
detection happens automatically once when the minute register
reaches x9h or x0h minutes.
Similar wording applies to the LBAT75 bit.
This means that if the device is powered off for more than 10 minutes,
the LBAT85 bit is guaranteed to be set. Upon power-on, unless we're
close enough to the end of a minute and/or the boot is slow enough
that the second register passes 59, the LBAT85 bit is still set when
the kernel (or early userspace) reads the RTC to set the system's
wallclock time.
Another minor problem is with the bit logic. If the 75% level is
reached, logically we're also below 85%, so both bits would most
likely be set. So even if the battery is below 75%, the warning would
still say "voltage dropped below 85%".
A third problem is that the driver and current DT binding offer no way
to indicate the nominal battery level and/or settings of the Battery
Level Monitor Trip Bits. Since the default value of the VB85TP[2:0] and
VB75TP[2:0] bits are 000, this means the actual setting of the
LBAT85/LBAT75 bits in VDD mode doesn't happen until the battery is below
2.125V/1.875V, which for a standard 3V battery is way too late.
A fourth problem is emitting this warning from ->read_time:
util-linux' hwclock will, in the absence of support for getting an
interrupt when the seconds counter is updated, issue
ioctl(RTC_RD_TIME) in a busy-loop until it sees a change in the
seconds field. In that case, if the battery low bits are set (either
genuinely, more than a minute after boot, due to the battery actually
being low, or as above, bogusly shortly after boot), the kernel log is
swamped with hundreds of identical warnings.
Subsequent patches will add such bindings and driver support, and also
proper support for RTC_VL_READ. For now, remove the broken warning.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Link: https://lore.kernel.org/r/20230615105826.411953-2-linux@rasmusvillemoes.dk
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Referring to platform_get_irq()'s definition, the return value has
already been checked if ret < 0, and printed via dev_err_probe().
Calling dev_err_probe() one more time outside platform_get_irq()
is obviously redundant.
Removing dev_err_probe() outside platform_get_irq() to clean up
above problem.
Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Link: https://lore.kernel.org/r/20230802093650.976352-1-chenjiahao16@huawei.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
After a previous commit changed the driver over to
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(), the suspend/resume
functions must no longer be hidden behind an #ifdef:
In file included from include/linux/clk.h:13,
from drivers/rtc/rtc-stm32.c:8:
drivers/rtc/rtc-stm32.c:927:39: error: 'stm32_rtc_suspend' undeclared here (not in a function); did you mean 'stm32_rtc_probe'?
927 | SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(stm32_rtc_suspend, stm32_rtc_resume)
| ^~~~~~~~~~~~~~~~~
include/linux/kernel.h:58:44: note: in definition of macro 'PTR_IF'
58 | #define PTR_IF(cond, ptr) ((cond) ? (ptr) : NULL)
| ^~~
include/linux/pm.h:329:26: note: in expansion of macro 'pm_sleep_ptr'
329 | .suspend_noirq = pm_sleep_ptr(suspend_fn), \
| ^~~~~~~~~~~~
Fixes: fb9a7e5360 ("rtc: stm32: change PM callbacks to "_noirq()"")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230801105932.3738430-1-arnd@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The driver was introduced when .probe_new was the right probe callback
to use for i2c drivers. Today .probe is the right one (again) and the
driver was already switched in commit 31b0cecb40 ("rtc: Switch i2c
drivers back to use .probe()") but the name continued to include "_new"
in its name.
To prevent code readers wondering about what might be new here, drop
that irritating part of the name.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230725070429.383070-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230724205456.767430-1-robh@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Property "trickle-resistor-ohms" allows us to set trickle charger
resistor. However there is no possibility to disable it afterwards.
Add support for "aux-voltage-chargeable" property which can be used to
enable/disable the trickle charger circuit explicitly. The default
behavior of the code is kept as it is!
Additionally, lets make sure we only update internal EEPROM in case of a
change. This prevents wear due to excessive EEPROM writes on each probe.
Signed-off-by: Andrej Picej <andrej.picej@norik.com>
Link: https://lore.kernel.org/r/20230623081533.76334-1-andrej.picej@norik.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The added HAS_IOPORT dependency might not actually be necessary as Geert
points out, but the driver is also only used on one architecture. Sparc
is also a special case here since it converts port numbers into virtual
addresses rather than having them mapped into a particular part of the
__iomem address space, so the difference is actually not important here.
Add a dependency on sparc, but allow compile-testing otherwise, to
make this clearer without anyone having to spend much time modernizing
the driver beyond that.
Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: David S. Miller <davem@davemloft.net>
Link: https://lore.kernel.org/all/CAMuHMdWEx0F=fNei4Bz_JPkuvoaN-+zk08h0i8KnSi_VjO615g@mail.gmail.com/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230719192835.1025406-1-arnd@kernel.org
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Drop enum pcf85063_type and split the array pcf85063_cfg[] as individual
variables, and make lines shorter by referring to e.g. &pcf85063_cfg
instead of &pcf85063_cfg[PCF85063].
Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/r/20230717124059.196244-3-biju.das.jz@bp.renesas.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The pcf85063_ids[].driver_data could store a pointer to the config,
like for DT-based matching, making I2C and DT-based matching
more similar.
After that, we can simplify the probe() by replacing of_device_get_
match_data() and i2c_match_id() by i2c_get_match_data() as we have
similar I2C and DT-based matching table.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230717124059.196244-2-biju.das.jz@bp.renesas.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Simplify the probe() by replacing of_device_get_match_data() and
i2c_match_id() by i2c_get_match_data() as we have similar I2C
and DT-based matching table.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230710114747.106496-1-biju.das.jz@bp.renesas.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Fix a few style issues reported by checkpatch.pl:
- Unnecessary parentheses
- Lines should not end with a '('
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-8-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
stm32_rtc_valid_alrm function has some issues :
- arithmetical operations are impossible on BCD values
- "cur_mon + 1" can overflow
- the use case with the next month, the same day/hour/minutes went wrong
To solve that, we prefer to use timestamp comparison.
e.g. : On 5 Dec. 2021, the alarm limit is 5 Jan. 2022 (+31 days)
On 31 Jan 2021, the alarm limit is 28 Feb. 2022 (+28 days)
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-7-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The RTC driver stops the RTCAPB clock during suspend, but the
irq handler from RTC is called before starting clock. Then we are
blocked while accessing RTC registers.
We changes PM callbacks to '_no_irq()' to disable irq during
resume callback and so irq handler will be called after the enable
of RTCAPB clock.
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-6-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Change stm32-rtc driver to not generate an error message when
device probe operation is deferred for a clock.
Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-5-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The rtc is used to update the stgen counter on wake up from
low power modes, so it needs to be as much accurate as possible.
The maximization of asynchronous divider leads to a 4ms rtc
precision clock.
By decreasing pred_a to 0, it will have pred_s=32767 (when
need_accuracy is true), so stgen clock becomes more accurate
with 30us precision.
Nevertheless this will leads to an increase of power consumption.
Signed-off-by: Christophe Guibout <christophe.guibout@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-4-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
RTC counters are stopped when INIT bit in ISR register is set and
start counting from the (eventual) new value when INIT is reset.
In stm32_rtc_init(), called during probe, the INIT bit is set to
program the prescaler and the 24h mode. This halts the RTC counter
at each probe tentative causing the RTC time to loose from 0.3s to
0.8s at each kernel boot.
If the RTC is battery powered, both prescaler value and 24h mode
are kept during power cycle and there is no need to program them
again.
Check if the desired prescaler value and the 24h mode are already
programmed, then skip reprogramming them to avoid halting the time
counter.
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-3-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Date and time are read from two separate RTC registers.
To ensure consistency between the two registers, reading the time
register locks the values in the shadow date register until the
date register is read.
Thus, the whole date/time read requires reading the time register
first, followed by reading the date register.
If the reads are done in reversed order, the shadow date register
will remain locked until a future read operation. The future read
will read the former date value that could be already invalid.
Fix the read order of date/time registers in stm32_rtc_valid_alrm()
Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
Link: https://lore.kernel.org/r/20230705174357.353616-2-valentin.caron@foss.st.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The PCF2127/29 do NOT support alarms with a 1 second resolution, but
the PCF2131 does.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-17-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The watchdog value register cannot be read on the PCF2131 after being
set.
Add a new flag to identify which variant has read access to this
register, and use this flag to selectively test if watchdog timer was
started by bootloader.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-16-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Introduce in the configuration structure two new values to hold the
watchdog clock source and the min_hw_heartbeat_ms value.
The minimum and maximum timeout values are automatically computed from
the watchdog clock source value for each variant.
The PCF2131 has no 1Hz watchdog clock source, as is the case for
PCF2127/29.
The next best choice is using a 1/4Hz clock, giving a watchdog timeout
range between 4 and 1016s. By using the same register configuration as
for the PCF2127/29, the 1/4Hz clock source is selected.
Note: the PCF2127 datasheet gives a min/max range between 1 and 255s,
but it should be between 2 and 254s, because the watchdog is triggered
when the timer value reaches 1, not 0.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-15-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The sequence for updating the time/date registers is slightly
different between PCF2127/29 and PCF2131.
For PCF2127/29, during write operations, the time counting
circuits (memory locations 03h through 09h) are automatically blocked.
For PCF2131, time/date registers write access requires setting the
STOP bit and sending the clear prescaler instruction (CPR). STOP then
needs to be released once write operation is completed.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-14-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The PCF2127 and PCF2129 have one output interrupt pin. The PCF2131 has
two, named INT_A and INT_B. The hardware support that any interrupt
source can be routed to either one or both of them.
Force all interrupt sources to go to the INT A pin.
Support to route any interrupt source to INT A/B pins is not supported
by this driver at the moment.
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20230622145800.2442116-13-hugo@hugovil.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
