The datasheet of the PCF2127 states, it is recommended to process an OTP
refresh once the power is up and the oscillator is operating stable. The
OTP refresh takes less than 100 ms to complete.
Signed-off-by: Philipp Rosenberger <p.rosenberger@kunbus.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210118085752.5759-3-p.rosenberger@kunbus.com
To resume normal operation after a total power loss (no or empty
battery) the "Power-On Reset Override (PORO)" facility needs to be
disabled.
The register reset value sets the PORO enabled and the data sheet
recommends setting it to disabled for normal operation.
From what I've seen on the PCF2127 and PCF2129 there is no event
generated at the interrupt pin (INT), as long the PORO bit is set. This
behavior is not documented in the manual.
Signed-off-by: Philipp Rosenberger <p.rosenberger@kunbus.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210118085752.5759-2-p.rosenberger@kunbus.com
Move the alarm callbacks in pcf2127_rtc_ops and use RTC_FEATURE_ALARM to
signal to the core whether alarms are available instead of having a
supplementary struct rtc_class_ops without alarm callbacks.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210110231752.1418816-8-alexandre.belloni@bootlin.com
Most boards using the pcf2127 chip (in my bubble) don't make use of the
watchdog functionality and the respective output is not connected. The
effect on such a board is that there is a watchdog device provided that
doesn't work.
So only register the watchdog if the device tree has a "reset-source"
property.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[RV: s/has-watchdog/reset-source/]
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201218101054.25416-3-rasmus.villemoes@prevas.dk
rtc_register_device() is a managed interface but it doesn't use devres
by itself - instead it marks an rtc_device as "registered" and the devres
callback for devm_rtc_allocate_device() takes care of resource release.
This doesn't correspond with the design behind devres where managed
structures should not be aware of being managed. The correct solution
here is to register a separate devres callback for unregistering the
device.
While at it: rename rtc_register_device() to devm_rtc_register_device()
and add it to the list of managed interfaces in devres.rst. This way we
can avoid any potential confusion of driver developers who may expect
there to exist a corresponding unregister function.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201109163409.24301-8-brgl@bgdev.pl
rtc_nvmem_register() is a managed interface. It doesn't require any
release function to be called at driver detach. To avoid confusing
driver authors, let's rename it to devm_rtc_nvmem_register() and add it
to the list of managed interfaces in Documentation/.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201109163409.24301-6-brgl@bgdev.pl
These functions should return zero on success. Non-zero returns are
treated as error. On some paths, this doesn't matter but in
nvmem_cell_read() a non-zero return would be passed to ERR_PTR() and
lead to an Oops.
Fixes: d6c3029f32 ("rtc: pcf2127: add support for accessing internal static RAM")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201022070451.GA2817669@mwanda
The obvious advantages are:
- The linker can drop the watchdog functions if CONFIG_WATCHDOG is off.
- All watchdog stuff grouped together with only a single function call
left in generic code.
- Watchdog register is only read when it is actually used.
- Less #ifdefery
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200924105256.18162-2-u.kleine-koenig@pengutronix.de
Fix a bug when not specify interrupts property in dts
as follows,
rtc-pcf2127-i2c 1-0051: failed to request alarm irq
rtc-pcf2127-i2c: probe of 1-0051 failed with error -22
Signed-off-by: Biwen Li <biwen.li@nxp.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200915073213.12779-1-biwen.li@oss.nxp.com
Fix multiple issues when handling alarms:
- Use threaded interrupt to avoid scheduling when atomic
- Stop matching on week day as it may not be set correctly
- Avoid parsing the DT interrupt and use what is provided by the i2c or
spi subsystem
- Avoid returning IRQ_NONE in case of error in the interrupt handler
- Never write WDTF as specified in the datasheet
- Set uie_unsupported, as for the pcf85063, setting alarms every seconds
is not working correctly and confuses the RTC.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200812085114.474903-1-alexandre.belloni@bootlin.com
The PCA2129 is the automotive grade version of the PCF2129.
add it to the list of compatibles.
Signed-off-by: Liam Beguin <lvb@xiphos.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20200630024211.12782-2-liambeguin@gmail.com
Driver does not use module parameter for nowayout, so it need to
statically initialize status variable of the watchdog_device based
on CONFIG_WATCHDOG_NOWAYOUT.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200604162602.76524-1-bruno.thomsen@gmail.com
Linux should handle when the pcf2127 watchdog feature is enabled by the
bootloader. This is done by checking the watchdog timer value during
init, and set the WDOG_HW_RUNNING flag if the value differs from zero.
Signed-off-by: Martin Hundebøll <martin@geanix.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191021080838.2789-1-martin@geanix.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Disable watchdog registation when kernel is build without
watchdog functionality, and enable watchdog core otherwise.
This removes compile errors like the one below:
drivers/rtc/rtc-pcf2127.o: in function `pcf2127_probe.constprop.3':
rtc-pcf2127.c:(.text.unlikely+0x2c8): undefined reference to
`devm_watchdog_register_device'
Watchdog feature in chip will always be configured as
this is safe to do in both cases and minimize code churn.
Reported-by: Hulk Robot <hulkci@huawei.com>
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: bbc597561ce1 ("rtc: pcf2127: add watchdog feature support")
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190827143656.4734-1-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Add support for integrated tamper detection function in both PCF2127 and
PCF2129 chips. This patch implements the feature by adding an additional
timestamp0 file to sysfs device path. This file contains seconds since
epoch, if an event occurred, or is empty, if none occurred.
Interface should match ISL1208 and RV3028 RTC drivers.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-5-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Add partial support for the watchdog functionality of
both PCF2127 and PCF2129 chips.
The programmable watchdog timer is currently using a fixed
clock source of 1Hz. This result in a selectable range of
1-255 seconds, which covers most embedded Linux use-cases.
Clock sources of 4096Hz, 64Hz and 1/60Hz is mostly useful
in MCU use-cases.
Countdown timer not available when using watchdog feature.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190822131936.18772-4-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The previous fix listed bulk read of registers as root cause of
accendential disabling of watchdog, since the watchdog counter
register (WD_VAL) was zeroed.
Fixes: 3769a375ab rtc: pcf2127: bulk read only date and time registers.
Tested with the same PCF2127 chip as Sean reveled root cause
of WD_VAL register value zeroing was caused by reading CTRL2
register which is one of the watchdog feature control registers.
So the solution is to not read the first two control registers
(CTRL1 and CTRL2) in pcf2127_rtc_read_time as they are not
needed anyway. Size of local buf variable is kept to allow
easy usage of register defines to improve readability of code.
Debug trace line was updated after CTRL1 and CTRL2 are no longer
read from the chip. Also replaced magic numbers in buf access
with register defines.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-3-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cleanup of defines to follow kernel coding style and increase code
readability by using same register and bit define style.
Change PCF2127_REG_RAM_{addr_MSB,wrt_cmd,rd_cmd} to upper case as
kernel coding guide section 12 'Macros, Enums and RTL' states
"Names of macros defining constants and labels in enums are capitalized".
Improve readability of RAM register comment by making whole sentences.
Remove parentheses from register defines as they are only used
for expressions and not constants.
As there are no clear style for name of registers and bits in the
kernel drivers, I suggest the following for at least this driver,
but hopefully also other RTC drivers.
Register name should follow this convention:
[chip]_REG_[reg name] 0xXX
Bit name should follow this convention, so it clearly states which
chip register it's part of:
[chip]_BIT_[reg name]_[bit name] BIT(X)
Additionally I suggest bit defines are always placed right below
its corresponding register define and using an extra tab indentation
for the BIT(X) part. This will visually make it easy to see that bit
defines are part of the complete register definition.
Rename PCF2127_OSF to PCF2127_BIT_SC_OSF and move it right below
PCF2127_REG_SC. This will improve readability of bit checks as it's
easy to verify that it uses the correct register.
Move end of line comments above register defines as it's more like
a heading for 1 register define and up to 8 bit defines or a
collection of registers that are close related like timestamp
split across 6 registers.
Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Link: https://lore.kernel.org/r/20190822131936.18772-2-bruno.thomsen@gmail.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The PCF2127 has 512 bytes of internal static RAM and this patch expands
the driver to access this memory.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
The RTC core is always calling rtc_valid_tm after the read_time callback.
It is not necessary to call it just before returning from the callback.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Read control registers one by one and bulk read time registers.
This fixes when the clock is read, the watchdog counter register is zeroed.
Signed-off-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
There are only a few differences between PCF2127 and PCF2129 (PCF2127
has 512 bytes of general purpose SRAM and count-down timer).
The rtc-pcf2127 driver currently doesn't use the PCF2127 specific
functionality and Kconfig help text already says this driver supports
PCF2127/29, so we can simply add pcf2129 to device id list.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
pcf2127 has selectable I2C-bus and SPI-bus interface support.
This adds support for SPI interface.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
pcf2127 has selectable I2C-bus and SPI-bus interface support.
Currently rtc-pcf2127 driver only supports I2C.
This is preparation for support for SPI interface.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
A driver version is only really sensible for oot drivers. Also the
dev_info about having found a chip only signals that allocating the
driver data succeeded and so isn't worth much.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The flag reported on the RTC_READ_VL ioctl is only initialized when the
date is read out. So the voltage low value doesn't represent reality but
the status at the time the date was read (or 0 if the date was not read
yet).
Moreover when userspace requests a value via an ioctl there is no added
benefit to also make a prosa representation of this (and other) values
appear in the kernel log so remove the calls to dev_info and the driver
data members to track their state.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The header of the pcf2127 driver specifies GPL v2 only as license, so
use "GPL v2" as module license specifier instead of "GPL" as the latter
means "GNU Public License v2 or later".
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The PCF2127 datasheet states that it's wrong to say that the date in
unreliable if BLF (battery low flag) is set but instead, OSF (seconds
register) should be used to check if oscillator, for any reason, stopped.
Battery may be low (usually below 2V5 threshold) but the date may be anyway
correct (typically date is unreliable when input voltage is below 1V2).
Signed-off-by: Andrea Scian <andrea.scian@dave.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
There's a wrong comment in some RTC drivers that say it's better to ignore
rtc_valid_tm() when reading RTC timestamp. However this is wrong and is
better to return to the userspace the error if timestamp is not valid.
Signed-off-by: Andrea Scian <andrea.scian@dave.eu>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Fix a coccinelle error regarding usage of IS_ERR and PTR_ERR instead of
PTR_ERR_OR_ZERO.
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The 'remove' function is empty and does not do anything. Delete it.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Biwen Li