Instead of adding a binary sysfs attribute from the driver (which suffers
from a race condition as the attribute appears after the device), use the
core to register an nvmem device.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This removes a possible race condition and crash and allows for further
improvement of the driver.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

rv8803_remove() is now empty, remove it.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Instead of adding a binary sysfs attribute from the driver (which suffers
from a race condition as the attribute appears after the device), use the
core to register an nvmem device.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This removes a possible race condition and allows for further improvement
of the driver.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Many RTCs have an on board non volatile storage. It can be battery backed
RAM or an EEPROM. Use the nvmem subsystem to export it to both userspace
and in-kernel consumers.

This stays compatible with the previous (non documented) ABI that was using
/sys/class/rtc/rtcx/device/nvram to export that memory. But will warn about
the deprecation.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

While highly unlikely, it is possible to get an interrupt as soon as it is
requested. In that case, at91_rtc_interrupt() will be called with rtc ==
NULL.

Solve that by using devm_rtc_allocate_device/rtc_register_device.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Introduce rtc_register_device() to register an already allocated and
initialized struct rtc_device. It automatically sets up the owner and the
two steps allocation/registration will allow to remove race conditions in
the IRQ handling of some driver. It also allows to properly extend the core
without adding more arguments to rtc_device_register().
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Create rtc_device_get_id to allocate the id for an RTC.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Create rtc_allocate_device to allocate memory for a struct rtc_device and
initialize it.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This patch adds support for STM32H7 RTC. On STM32H7, the RTC bus interface
clock (APB clock) needs to be enabled.
Signed-off-by: NAmelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The ds1308 variant is very similar to the already supported ds1338
variant, it have more debug registers and a square wave clock output.
Signed-off-by: NSean Nyekjaer <sean.nyekjaer@prevas.dk>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

DS3232/DS3234 has the temperature registers with a resolution of 0.25
degree celsius. This enables to get the value through hwmon.

	# cat /sys/class/hwmon/hwmon0/temp1_input
	37250
Signed-off-by: NKirill Esipov <yesipov@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

We should change this post-op to a pre-op because we want the loop to
exit with "timeout" set to zero.

Fixes: 0a89b553 ("nuc900/rtc: change the waiting for device ready implement")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The Gemini RTC is actually a generic IP block from Faraday
Technology names FTRTC010. Rename the driver file and all
symbols to match this IP name.

The relationship can be clearly seen in the U-Boot driver
posted by Po-Yu Chuang for the Faraday A320 board:
https://lists.denx.de/pipermail/u-boot/2009-September/061326.html

Remove the dependency on ARCH_GEMINI but select the driver
for ARCH_GEMINI so we get a smooth transition. The IP block
is synthsized on different silicon and architectures.

Cc: Po-Yu Chuang <ratbert@faraday-tech.com>
Acked-by: NHans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This makes the Gemini optionally take two clock references to
the PCLK and EXTCLK. As we are adding a clock framework to the
Gemini platform we need to make sure that we get the right
references.
Acked-by: NHans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The driver has lots of places with chip-specific code what doesn't
necessarily facilitate maintenance.

Let's describe chip-specific differences in century bit handling
in struct chip_desc to improve this.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

After the switch to regmap we can now make use of regmap_update_bits
to simplify read/modify/write ops.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This adds support for the Broadcom STB wake-timer which is a timer in
the chip's 27Mhz clock domain that offers the ability to wake the system
(wake-up source) from suspend states (S2, S3, S5). It is supported using
the rtc framework allowing us to configure alarms for system wake-up.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NMarkus Mayer <mmayer@broadcom.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Add support for yet another RTC chip, Epson RX8130CE. This time around,
the chip has slightly permutated registers and also the register starts
at 0x10 instead of 0x0 .

So far, we only support the RTC and NVRAM parts of the chip, Alarm and
Timer is not supported.
Signed-off-by: NMarek Vasut <marex@denx.de>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Nishanth Menon <nm@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

clk_enable() can fail so handle such case.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

clk_prepare_enable() can fail so handle such case.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

All instances of struct s3c_rtc_data are in fact static const thus
put in rodata so we should not drop the const while getting the pointer
to them.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

There is no need for casting to void pointer for of_device_id data.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Minor cleanups to make the code easier to read. No functional changes.
1. Remove one space before labels as this is nowadays mostly preferred.
2. Fix indentation of arguments in function calls.
3. Split structure member declaration.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

In other error paths in probe, centralized exit point was used so make
this consistent.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This variable was never used. With GCC 6.2, we get the following warning:

drivers/rtc/rtc-mxc.c:44:18: warning: ‘PIE_BIT_DEF’ defined but not used [-Wunused-const-variable=]
 static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
Signed-off-by: NDiaz de Grenu, Jose <Jose.DiazdeGrenu@digi.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Provide an implementation of the callback
rtc_class_ops.alarm_irq_enable for rtc-opal driver. This callback is
called when the wake alarm is disabled via the command:

'echo 0 > /sys/class/rtc/rtc0/wakealarm'

Without this the Timed-Power-On(TPO) config remains set even when its
disabled by the above command and FSP will still force machine
boot at previously configured alarm time.

The callback is implemented as function opal_tpo_alarm_irq_enable()
which calls opal_set_tpo_time() with alarm.enabled == 0. A branch is
added to opal_set_tpo_time() to handle this case by passing y_m_d ==
h_m_s_ms == 0 to opal as arguments for opal_tpo_write() call.
Signed-off-by: NVaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

rtc->name is only used in messages were it is superfluous. Remove it
completely from the structure.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

ds1307->rtc->name is a copy of ds1307->name, use it instead.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

pcf8563->rtc->name is a copy of pcf8563_driver.driver.name, use it instead
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

rtc->name is superfluous here because the rtc is already registered at that
point and its name has already been printed.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The name sysfs attribute is not useful in its current form because of all
the drivers:
 - 3 are using the feature correctly
 - 2 are clearly misusing it
 - 60 are using driver.name, either directly or indirectly
 - 46 are using pdev->name
 - 8 are using client->name
 - 31 are using a variation of driver.name (addition or removal of rtc-,
   -rtc, _rtc, rtc_)

Make it uniform and use the driver name and the device name.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

In function __rtc_read_alarm() its possible for an alarm time-stamp to
be invalid even after replacing missing components with current
time-stamp. The condition 'alarm->time.tm_year < 70' will trigger this
case and will cause the call to 'rtc_tm_to_time64(&alarm->time)'
return a negative value for variable t_alm.

While handling alarm rollover this negative t_alm (assumed to seconds
offset from '1970-01-01 00:00:00') is converted back to rtc_time via
rtc_time64_to_tm() which results in this error log with seemingly
garbage values:

"rtc rtc0: invalid alarm value: -2-1--1041528741
2005511117:71582844:32"

This error was generated when the rtc driver (rtc-opal in this case)
returned an alarm time-stamp of '00-00-00 00:00:00' to indicate that
the alarm is disabled. Though I have submitted a separate fix for the
rtc-opal driver, this issue may potentially impact other
existing/future rtc drivers.

To fix this issue the patch validates the alarm time-stamp just after
filling up the missing datetime components and if rtc_valid_tm() still
reports it to be invalid then bails out of the function without
handling the rollover.
Reported-by: NSteve Best <sbest@redhat.com>
Signed-off-by: NVaibhav Jain <vaibhav@linux.vnet.ibm.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

On PowerNV platform when Timed-Power-On(TPO) is disabled, read of
stored TPO yields value with all date components set to '0' inside
opal_get_tpo_time(). The function opal_to_tm() then converts it to an
offset from year 1900 yielding alarm-time == "1900-00-01
00:00:00". This causes problems with __rtc_read_alarm() that
expecting an offset from "1970-00-01 00:00:00" and returned alarm-time
results in a -ve value for time64_t. Which ultimately results in this
error reported in kernel logs with a seemingly garbage value:

"rtc rtc0: invalid alarm value: -2-1--1041528741
2005511117:71582844:32"

We fix this by explicitly handling the case of all alarm date-time
components being '0' inside opal_get_tpo_time() and returning -ENOENT
in such a case. This signals generic rtc that no alarm is set and it
bails out from the alarm initialization flow without reporting the
above error.
Signed-off-by: NVaibhav Jain <vaibhav@linux.vnet.ibm.com>
Reported-by: NSteve Best <sbest@redhat.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Some devices supported by the m41t80 driver have a programmable
square-wave output signal (see M41T80_FEATURE_SQ).

This enables to use this feature as a clock provider of common
clock framework.
Signed-off-by: NGary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

In order to use the proper clock framework to control this feature.
Signed-off-by: NGary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This patch is only relevant for RTC with the SQ_ALT feature which
means the clock output frequency divider is stored in the weekday
register.

Current implementation discards the previous dividers value and clear
them as soon as the time is set.
Signed-off-by: NGary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Currently setting an alarm clears the SQWE bit which means that the
clock output is disabled no matter its previous state.
Signed-off-by: NGary Bisson <gary.bisson@boundarydevices.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

This patch extends the fixes for ds1337, ds1339, ds3231 in commit
8bc2a407 ("rtc: ds1307: add support for the DT property
'wakeup-source'") to mcp794xx devices, so that those parts can similarly be
used as a wakeup source without an IRQ to the processor.

Tested on Raspberry Pi ZeroW with MCP79400.
Signed-off-by: NDavid Lowe <dave-lowe@ntlworld.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>