Commit 22652ba7 ("rtc: stop validating rtc_time in .read_time") removed
the code but not the associated comment.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201015191135.471249-1-alexandre.belloni@bootlin.com

New driver for the Microcrystal RV-3032, including support for:
 - Date/time
 - Alarms
 - Low voltage detection
 - Trickle charge
 - Trimming
 - Clkout
 - RAM
 - EEPROM
 - Temperature sensor
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201013144110.1942218-3-alexandre.belloni@bootlin.com

Document the Microcrystal RV-3032 device tree bindings
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201013144110.1942218-2-alexandre.belloni@bootlin.com

Some RTCs have a trickle charge that is able to output different voltages
depending on the type of the connected auxiliary power (battery, supercap,
...). Add a property allowing to specify the necessary voltage.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20201013144110.1942218-1-alexandre.belloni@bootlin.com

If RV3028_CTRL1_EERD is not set (this is the default), the RTC will refresh
the RAM configuration registers from the EEPROM at midnight. It is
necessary to save the RAM registers back to EEPROM after modifying them.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201009153101.721149-4-alexandre.belloni@bootlin.com

Both rv3028_eeprom_write and rv3028_eeprom_read enable EERD before sending
commands to the EEPROM and restore it afterwards. Factorize this code.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201009153101.721149-3-alexandre.belloni@bootlin.com

Version 1.0 of the application manual had the wrong resistor values. Fix
them according to version 1.1
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201009153101.721149-2-alexandre.belloni@bootlin.com

rv3028_clkout_set_rate unconditionally sets RV3028_CLKOUT_CLKOE but
clk_set_rate may be called with the clock disabled. Ensure the clock is
kept disabled if it was not yet enabled.

Also, the actual rate was overwritten when enabling the clock, properly
write to the register only once.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201009153101.721149-1-alexandre.belloni@bootlin.com

Removing the struct member "dev" in mt6397 RTC driver because it's not
initialized and the only usage is for one debugging message.

Also fixed a typo in the error message.
Signed-off-by: Fei Shao <fshao@chromium.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201008093414.1911699-1-fshao@chromium.org

Simplify the return expression.
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200921082449.2591981-1-liushixin2@huawei.com

Simplify the return expression.
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Kevin Hilman <khilman@baylibre.com>
Link: https://lore.kernel.org/r/20200919100856.1639319-1-liushixin2@huawei.com

Since the switch to using regmap this function no longer takes the
I2C client struct as argument nor do we even interact with the client
anywhere other than when creating the regmap.

Rename it to a less misleading name: "rx8010_init()".
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917114656.9036-1-brgl@bgdev.pl

The ds1307 charger infrastructure now allows to add a rx8130 charger
setup that..

- does not depend on trickle-resistor-ohms
- does not use DS13XX_TRICKLE_CHARGER_MAGIC trickle-charge select (TCS)
  bits
- keeps previous no-charge behavior for device trees without
  aux-voltage-chargeable

Make that happen.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917183246.19446-9-bst@pengutronix.de

Prefer aux-voltage-chargeable over trickle-diode-disable and set diode
accordingly. This is then passed to the chip's appropriate charge setup
function.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917183246.19446-8-bst@pengutronix.de

Some RTC's batteries and supercaps were charged by default until now.
In contrast other RTCs allow charging but the driver did not configure
them to do so until now. These must not be charged by default to stay
backwards compatible.

In order to do that, store the charge default per chip.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917183246.19446-7-bst@pengutronix.de

Make trickle-resistor-ohms optional for charging setups that do not
require specifying ROUT bits (specifying the resistor value between Vcc
and Vbackup). In order to allow specifying that, introduce
requires_trickle_resistor per chip.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917183246.19446-6-bst@pengutronix.de

DS13XX_TRICKLE_CHARGER_MAGIC sets the trickle-charge select (TCS) bits
(7..4). The datasheet of Maxim Integrated's DS1339 [1] for instance
reads:

"To prevent accidental enabling, only a pattern on 1010 enables the
trickle charger. All other patterns disable the trickle charger."

Since not all RTCs connected to a backup battery or supercap use these
bits DS13XX_TRICKLE_CHARGER_MAGIC should not get applied for all charger
setups unconditionally.
Epson's RX8130 is such an example: Instead of TCS bits "SMPTSEL1",
"SMPTSEL0",  "CHGEN" and "INIEN" are expected as bit 7..4.

DS1339 and DS1340 are currently the only RTCs in the ds1307 driver that
apply DS13XX_TRICKLE_CHARGER_MAGIC to their setup register value. So
apply DS13XX_TRICKLE_CHARGER_MAGIC in do_trickle_setup_ds1339() which
is used by both RTCs.

[1] https://datasheets.maximintegrated.com/en/ds/DS1339-DS1339U.pdf
[2] https://support.epson.biz/td/api/doc_check.php?dl=app_RX8130CESigned-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200917183246.19446-5-bst@pengutronix.de

Epson's RX8130 was not charged before. A related patch will allow
optional charging.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200917183246.19446-4-bst@pengutronix.de

trickle-diode-disable is deprecated, so reflect that in the driver's
binding and add the new aux-voltage-chargeable.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200917183246.19446-3-bst@pengutronix.de

Some RTCs can be equipped with a chargeable battery or supercap.
Every RTC allowing this whose driver's implement it are charged by
default. To disable this the trickle-diode-disable flag exists.

If a driver did not support charging and some time later one wants to
add that feature, there is currently no way to do it without breaking
dt backwards compatibility. RTCs on boards without the
trickle-diode-disable flag in their device tree would suddenly charge
their battery/supercap which is a change in behavior.

Change that by introducing aux-voltage-chargeable, not as a flag but as
a uint32 enum allowing to set "do not charge" (0) or "charge" (1). This
dt property is optional, so we can now distinguish these cases.

Care must be taken to support the old behavior for device trees without
aux-voltage-chargeable nonetheless to stay compatible.
Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200917183246.19446-2-bst@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

ds1685_rtc_begin_data_access() tried to access an extended register before
enabling access to it by switching to bank 1. Depending on content in NVRAM
this could lead to an endless loop. While at it fix also switch back to
bank 0 in ds1685_rtc_end_data_access().
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Joshua Kinard <kumba@gentoo.org>
Link: https://lore.kernel.org/r/20200910084124.138560-1-tsbogend@alpha.franken.de

The only usage of st_rtc_ops is to assign its address to the ops field
in the rtc_device struct. which is a const pointer. Make it const to
allow the compiler to put it in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200913122644.35515-1-rikard.falkeborn@gmail.com

We don't need to check the time range manually in set_time(), we can
use range_min and range_max exposed by struct rtc_device.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-15-brgl@bgdev.pl

This driver requires SMBUS to work. We can relax this requirement if we
switch to using i2c regmap and let the regmap sub-system figure out how
to talk to the bus.

This also has the advantage of shrinking the code for register updates.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-14-brgl@bgdev.pl

We should generally use probe_new instead of probe when registering i2c
drivers. Convert rx8010 to using it.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-13-brgl@bgdev.pl

Use devm_rtc_allocate_device() + rtc_register_device() instead of the
deprecated devm_rtc_device_register().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-12-brgl@bgdev.pl

Using the size of the variable is preferred over using the size of its
type when allocating memory. Convert the call to devm_kzalloc() in
probe().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-11-brgl@bgdev.pl

Simple 'dev' looks better then repeated &client->dev and has the added
benefit of avoiding unnecessary line breaks.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-10-brgl@bgdev.pl

The 'err' local variable in rx8010_init_client() doesn't need to be
initialized.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-9-brgl@bgdev.pl

The time buffer len is used directly in this driver. For readability
it's better to define it as the difference between the date register
offsets and use sizeof() whenever referencing it.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-8-brgl@bgdev.pl

All other functions in this driver use 'err' for integer return values.
Do the same in rx8010_set_time() for consistency.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-7-brgl@bgdev.pl

The define values in this driver are close to their names and they are
separated by spaces. Use tabs instead and align all defines.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-6-brgl@bgdev.pl

Move local variables of the same type into a single line for better
readability.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-5-brgl@bgdev.pl

Remove brackets wherever they guard a single line.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-4-brgl@bgdev.pl

Remove an unnecessary newline after requesting the interrupt.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200914154601.32245-3-brgl@bgdev.pl

The way the driver is implemented is buggy for the (admittedly unlikely)
use case where there are two RTCs with one having an interrupt configured
and the second not. This is caused by the fact that we use a global
rtc_class_ops struct which we modify depending on whether the irq number
is present or not.

Fix it by using two const ops structs with and without alarm operations.
While at it: not being able to request a configured interrupt is an error
so don't ignore it and bail out of probe().

Fixes: ed13d89b ("rtc: Add Epson RX8010SJ RTC driver")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200914154601.32245-2-brgl@bgdev.pl

Common pattern of handling deferred probe can be simplified with
dev_err_probe().  Less code and the error value gets printed.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200830080937.14367-1-krzk@kernel.org

Original device id would conflict with crypto driver, change it.
Signed-off-by: Peng Ma <peng.ma@nxp.com>
Signed-off-by: Ran Wang <ran.wang_1@nxp.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200818063609.39859-1-ran.wang_1@nxp.com

Ensure the OSF flag is cleared on the DS1388 when the clock is set.

Fixes: df11b323 ("rtc: ds1307: handle oscillator failure flags for ds1388 variant")
Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200818013543.4283-1-chris.packham@alliedtelesis.co.nz