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
Issue:
- # hwclock -w
hwclock: RTC_SET_TIME: Invalid argument
Why:
- Relative commit: 8b9f9d4dc5 ("regmap: verify if register is
writeable before writing operations"), this patch
will always check for unwritable registers, it will compare reg
with max_register in regmap_writeable.
- The pcf85363/pcf85263 has the capability of address wrapping
which means if you access an address outside the allowed range
(0x00-0x2f) hardware actually wraps the access to a lower address.
The rtc-pcf85363 driver will use this feature to configure the time
and execute 2 actions in the same i2c write operation (stopping the
clock and configure the time). However the driver has also
configured the `regmap maxregister` protection mechanism that will
block accessing addresses outside valid range (0x00-0x2f).
How:
- Split of writing regs to two parts, first part writes control
registers about stop_enable and resets, second part writes
RTC time and date registers.
Signed-off-by: Biwen Li <biwen.li@nxp.com>
Link: https://lore.kernel.org/r/20190829021418.4607-1-biwen.li@nxp.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
It is not necessary to forward declare pcf85363_driver as it is not used
before being declared.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
regmap is abstracting the i2c functionalities the best it can, there is no
need to check.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Add support for NXP pcf85263 real-time clock. pcf85263 rtc is compatible
with pcf85363,except that pcf85363 has additional 64 bytes of RAM.
1 byte of nvmem is supported and exposed in sysfs (# is the instance
number,starting with 0): /sys/bus/nvmem/devices/pcf85x63-#/nvmem
Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
As per 8.2.6 Setting and reading the time in RTC mode, first stop the clok,
then reset it before setting the date and time registers. Finally, start
the clock.
This uses register address wrap around from 0x2f to 0x00 for efficiency.
This allows to set the clock with a millisecond accuracy (drift is not
corrected in this example):
RTC System
1325388767 1325388767.000029180
1325388768 1325388768.000018362
1325388769 1325388769.000006544
1325388770 1325388769.999992725
1325388771 1325388770.999974544
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Call rtc_nvmem_register instead of letting the core do it and stop using
the nvmem_config member of struct rtc_device.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Note that alarms are not currently implemented.
64 bytes of nvmem is supported and exposed in
sysfs (# is the instance number, starting with 0):
/sys/bus/nvmem/devices/pcf85363-#/nvmem
Signed-off-by: Eric Nelson <eric@nelint.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
