By using i2c_smbus_read_i2c_block_data() the code is now much simpler.
While at it: when reading the RTC's seconds register, all time/date registers
are frozen until the RTC's year register is read. So it is important to read
all time/date registers in one turn to not lose a second event. Make it more
clear why the read must happen in this way.
Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
pcf2123 has an offset register, which can be used to make minor
adjustments to the clock rate to compensate for temperature or
a crystal that is not exactly right.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
clock offset may be set and read in decimal parts per billion
attribute is /sys/class/rtc/rtcN/offset
The attribute is only visible for rtcs that have set_offset implemented.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
A number of rtc devices, such as the NXP pcf2123 include a facility
to adjust the clock in order to compensate for temperature or a
crystal, capacitor, etc, that results in the rtc clock not running
at exactly 32.768 kHz.
Data sheets I have seen refer to this as a clock offset, and measure it
in parts per million, however they often reference ppm to 2 digits of
precision, which makes integer ppm less than ideal.
We use parts per billion, which more than covers the precision needed
and works nicely within 32 bits
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
To make RTC block of MAX77686/MAX77802 as independent driver,
move the registration of i2c device, regmap for register access
and irq_chip for interrupt support inside the RTC driver.
Removed the same initialisation from MFD driver.
Having this change will allow to reuse this driver for different
PMIC/devices from Maxim Semiconductor if they kept same RTC IP on
different PMIC. Some of examples as PMIC MAX77620, MAX20024 where
same RTC IP used and hence driver for these chips will use this
driver only for RTC support.
Suggested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Get rid of referring parent device info for register access
all the places by making regmap as part of max77686 rtc
device info. This will also remove the need of storing parent
device info in max77686 rtc device info as this is no more required.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
At the moment the "sun6i" RTC drivers depends on having two specific
SoC families selected.
The Allwinner A64 SoC has the same RTC, so extend the Kconfig option
to allow inclusion of the driver for all Allwinner SoCs.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The RX6110 comes in two different variants: SPI and I2C.
This driver only supports the SPI variant.
If the need ever arises to also support the I2C variant, this driver
could easily be refactored to support both cases.
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
pcf2123 data sheet recommends a software reset when the chip
is first powered on. This change avoids resetting the chip
every time the driver is loaded, which has some negative effects.
There are several registers including a clock rate adjustment that really
should survive a reload of the driver (or reboot).
In addition, stopping and restarting the clock to verify the chip is
there is not a good thing once the time is set.
According to the data sheet, the seconds register has a 1 in
the high bit when the voltage has gotten low. We check for this
condition, as well as whether the time retrieved from the chip is
valid. We reset the rtc only if the time is not reliable and valid.
This is sufficient for checking for the presence of the chip,
as either all zeros or all 0xff will result in an invalid time/date
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Refactor chip reset items into its own function, isolating it from
the rest of the device probe.
Subsequent commits will avoid calling this code.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Add new functions pcf2123_write(), and pcf2123_write_reg().
Use named defines for the values being written.
This improves modularity and readability, and reduces lines of code.
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Add defines for all 16 registers in the pcf2123.
Add defines for useful bits from several registers
I've tried to document all the registers, and
as best as possible, all the special bits they employ
Use BIT() wherever possible in the bit definitions
Signed-off-by: Joshua Clayton <stillcompiling@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
DS3231 has the temperature registers with a resolution of 0.25
degree celsius. This enables to get the value through hwmon.
# cat /sys/class/i2c-adapter/i2c-2/2-0068/hwmon/hwmon0/temp1_input
21000
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
For RTC chips with no IRQ directly connected to the SoC, the RTC chip
can be forced as a wakeup source by stating that explicitly in
the device's .dts file using the "wakeup-source" boolean property.
This will guarantee the 'wakealarm' sysfs entry is available on the
device, if supported by the RTC.
With these changes to the driver rtc-ds1307 and the necessary entries
in the .dts file, I get an working ds1337 RTC on the Witty Pi extension
board by UUGear for the Raspberry Pi.
An example for the entry in the .dts file:
rtc: ds1337@68 {
compatible = "dallas,ds1337";
reg = <0x68>;
wakeup-source;
If the "wakeup-source" property is set, do not request an IRQ.
Set also UIE mode to unsupported, to get a working 'hwclock' binary.
Signed-off-by: Michael Lange <linuxstuff@milaw.biz>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
The mt6397 RTC driver can be built either when the MFD_MT6397 driver
is enabled (which selects IRQ_DOMAIN), or when compile testing.
The latter however fails without IRQ domains:
drivers/rtc/rtc-mt6397.c: In function 'mtk_rtc_probe':
drivers/rtc/rtc-mt6397.c:326:13: error: implicit declaration of function 'irq_create_mapping' [-Werror=implicit-function-declaration]
rtc->irq = irq_create_mapping(mt6397_chip->irq_domain, res->start);
This adds an explicit dependency for the COMPILE_TEST case.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Eddie Huang <eddie.huang@mediatek.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cleanup of entire driver of its dmesg output:
1. Remove printing of the function name, because printing device name is
sufficient. This also makes the dev_err()-like functions more compact
and readable (not need of line break).
2. Lower from info to debug printing of each RTC interrupt (no need to
make noise on each alarm).
3. Remove dev_info() at beginning of probe because a message is already
always printed by either probe failure or from registering the RTC
device as /dev/rtcX.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Juergen Borleis
Joshua Clayton
Oleksij Rempel
Oleksij Rempel
Akinobu Mita
Laxman Dewangan
Andre Przywara
Steffen Trumtrar
Leslie Lau
Michael Lange
Arnd Bergmann
Alexandre Belloni
Geliang Tang
Krzysztof Kozlowski