The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c

The change enables burst mode of access to SRAM for any read()/write()
operations, it is worth to mention that this may influence on
userspace, for instance prior to the change

  read(fd, buf, 1);
  read(fd, buf + 1, 1);

and

  read(fd, buf, 2);

sequences of syscalls over DS1511's sysfs "nvram" fd led to different
DS1511 state changes and/or buf content, if some userspace applications
are written specifically for DS1511 and exploit this strange
"feature", they may be impacted.

Also the change corrects NVRAM size accessible to userspace from 255
bytes to 256 bytes.
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller size in fs/sysfs/file.c
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The change removes redundant sysfs binary file boundary checks, since
this task is already done on caller side in fs/sysfs/file.c
Signed-off-by: NVladimir Zapolskiy <vz@mleia.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

If century field is supported by the RTC CMOS device, then we should use
it and then do not consider years greater that 169 as an error.

For information, the year field of the rtc_time structure contains the
value to add to 1970 to obtain the current year.

This was a hack to be able to support years for 1970 to 2069.
This patch remains compatible with this implementation.
Signed-off-by: NSylvain Chouleur <sylvain.chouleur@intel.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Commit dca1a4b5 ("clk: at91: keep slow clk enabled to prevent system
hang") added a workaround for the slow clock as it is not properly handled
by its users.

Get and use the slow clock as it is necessary for the at91rm9200 rtc.
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

drivers/rtc/rtc-gemini.c:151:1-3: WARNING: PTR_ERR_OR_ZERO can be used

 Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR

Generated by: scripts/coccinelle/api/ptr_ret.cocci
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

IS_ERR(_OR_NULL) already contain an 'unlikely' compiler flag and there
is no need to do that again from its callers. Drop it.

gemini driver was using likely() for a failure case while the rtc driver
is getting registered. That looks wrong and it should really be
unlikely. But because we are killing all the unlikely() flags, lets kill
that too.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Acked-by: NHans Ulli Kroll <ulli.kroll@googlemail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Sort included headers alphabetically.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

See help for clk_get_rate(): "obtain the current clock rate (in Hz) for a
clock source. This is only valid once the clock source has been enabled."

It currently returns the correct value but that may not stay that way.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

Sort included headers alphabetically.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

rtc->sclk necessarily points to a valid clocks at this point. Else the
probe would have aborted.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

In case of a probe error, it is possible to abort after issuing
clk_prepare_enable(). Ensure the clock is disabled and unprepared in that
case.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: NNicolas Ferre <nicolas.ferre@atmel.com>

The email address missed character ">", so add it.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The I2C core always reports the MODALIAS uevent as "i2c:<client name"
regardless if the driver was matched using the I2C id_table or the
of_match_table. So technically there's no need for a driver to export
the OF table since currently it's not used.

In fact, the I2C device ID table is mandatory for I2C drivers since
a i2c_device_id is passed to the driver's probe function even if the
I2C core used the OF table to match the driver.

And since the I2C core uses different tables, OF-only drivers needs to
have duplicated data that has to be kept in sync and also the dev node
compatible manufacturer prefix is stripped when reporting the MODALIAS.

To avoid the above, the I2C core behavior may be changed in the future
to not require an I2C device table for OF-only drivers and report the
OF module alias. So, it's better to also export the OF table to prevent
breaking module autoloading if that happens.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Commit d5a1c7e3 ("rtc-cmos: Add an alarm disable quirk") that
added a special quirk is not needed because [PATCH 1/2] of this
patchset makes the kernel more robust:
rtc-cmos: Cancel alarm timer if alarm time is equal to now+1 seconds
Signed-off-by: NAdrian Huang <ahuang12@lenovo.com>
Tested-by: NEgbert Eich <eich@suse.de>
Tested-by: NDiego Ercolani <diego.ercolani@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Steps to reproduce the problem:
	1) Enable RTC wake-up option in BIOS Setup
	2) Issue one of these commands in the OS: "poweroff"
	   or "shutdown -h now"
	3) System will shut down and then reboot automatically

Root-cause of the issue:
	1) During the shutdown process, the hwclock utility is used
	   to save the system clock to hardware clock (RTC).
	2) The hwclock utility invokes ioctl() with RTC_UIE_ON. The
	   kernel configures the RTC alarm for the periodic interrupt
	   (every 1 second).
	3) The hwclock uitlity closes the /dev/rtc0 device, and the
	   kernel disables the RTC alarm irq (AIE bit of Register B)
	   via ioctl() with RTC_UIE_OFF. But, the configured alarm
	   time is the current_time + 1.
	4) After the next 1 second is elapsed, the AF (alarm
	   interrupt flag) of Register C is set.
	5) The S5 handler in BIOS is invoked to configure alarm
	   registers (enable AIE bit and configure alarm date/time).
	   But, BIOS does not clear the previous interrupt status
	   during alarm configuration. Therefore, "AF=AIE=1" causes
	   the rtc device to trigger an interrupt.
	6) So, the machine reboots automatically right after shutdown.

This patch cancels the alarm timer if the following condictions are
met (suggested by Alexandre):
	1) The configured alarm time is equal to current_time + 1
	   seconds.
	2) The AIE timer is not in use.

The member 'alarm_expires' is introduced in struct cmos_rtc because
of the following reasons:
	1) The configured alarm time can be retrieved from
	   cmos_read_alarm(), but we need to take the 'wrapped
	   timestamp' and 'time rollover' into consideration. The
	   function __rtc_read_alarm() eliminates the concerns. To
	   avoid the duplicated code in the lower level RTC driver,
	   invoking __rtc_read_alarm from the lower level RTC driver
	   is not encouraged. Moreover, the compilation error 'the
	   undefined __rtc_read_alarm" is observed if the lower level
	   RTC driver is compiled as a kernel module.
	2) The uie_rtctimer.node.expires and aie_timer.node.expires can
	   be retrieved for the configured alarm time. But, the problem
	   is that either of them might configure the CMOS alarm time.
	   We cannot make sure UIE timer or AIE tiemr configured the
	   CMOS alarm time before. (uie_rtctimer or aie_timer is enabled
	   and then is disabled).
	3) The patch introduces the member 'alarm_expires' to keep the
	   newly configured alarm time, so the above-mentioned concerns
	   can be eliminated.

The issue goes away after 20-time shutdown tests.
Signed-off-by: NAdrian Huang <ahuang12@lenovo.com>
Tested-by: NEgbert Eich <eich@suse.de>
Tested-by: NDiego Ercolani <diego.ercolani@gmail.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Add DA9062 RTC support into the existing DA9063 RTC driver component by
using generic access tables for common register and bit mask definitions.

The following change will add generic register and bit mask support to the
DA9063 RTC. The changes are slightly complicated by requiring support for
three register sets: DA9063-AD, DA9063-BB and DA9062-AA.

The following alterations have been made to the DA9063 RTC:

- Addition of a da9063_compatible_rtc_regmap structure to hold all generic
  registers and bitmasks for this type of RTC component.
- A re-write of struct da9063 to use pointers for regmap and compatible
  registers/masks definitions
- Addition of a of_device_id table for DA9063 and DA9062 defaults
- Refactoring functions to use struct da9063_compatible_rtc accesses to
  generic registers/masks instead of using defines from registers.h
- Re-work of da9063_rtc_probe() to use of_match_node() and dev_get_regmap()
  to provide initialisation of generic registers and masks and access to
  regmap
Signed-off-by: NSteve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Implement the suspend/resume function in order to control rtc's irq_wake flag and handle as wakeup source.
Signed-off-by: NHenry Chen <henryc.chen@mediatek.com>
Acked-by: NEddie Huang <eddie.huang@mediatek.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Instead of creating wakealarm attribute manually, after the device has been
registered, let's rely on facilities provided by the attribute groups to
control which attributes are visible and which are not. This allows to
create all needed attributes at once, at the same time that we register RTC
class device.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Instead of using older style DEVICE_ATTR for wakealarm attribute let's
switch to using DEVICE_ATTR_RW that ensures consistent across the kernel
permissions on the attribute.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Users of rtc_does_wakealarm() return value treat it as boolean so let's
change the signature accordingly.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Since commit e6229bec ("rtc: make rtc_update_irq callable with irqs
enabled") rtc_update_irq() is callable with irqs enabled.
Signed-off-by: NHenri Roosen <henriroosen@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Since dab472eb ("i2c / ACPI: Use 0 to indicate that device does not
have interrupt assigned"), 0 is not a valid i2c client irq anymore, so
change all driver's checks accordingly.

The same issue occurs when the device is instantiated via device tree
with no IRQ, or from the i2c sysfs interface, even before the patch
above.
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com>
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

struct rtc embeds both struct dev and struct cdev.  Unfortunately character
device structure may outlive the parent rtc structure unless we set it up
as parent of character device so that it will stay pinned until character
device is freed.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Technically the address of rtc->dev can never be NULL, so get_device()
can never fail. Also caller of rtc_device_unregister() supposed to be
the owner of the device and thus have a valid reference. Therefore
call to get_device() is not needed here.
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Commit 59cca865 ("drivers/rtc/class.c: fix device_register() error
handling") correctly noted that naked kfree() should not be used after
failed device_register() call, however, while it added the needed
put_device() it forgot to remove the original kfree() causing double-free.

Cc: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

The current codes use CSR platform specific API exported by machine
codes to read/write RTC registers. they are:
sirfsoc_rtc_iobrg_readl()
sirfsoc_rtc_iobrg_writel()

commit b1999477 ("ARM: prima2: move to use REGMAP APIs for rtciobrg")
moves to regmap support, now we can move to use regmap APIs in RTC
driver.
Signed-off-by: NGuo Zeng <guo.zeng@csr.com>
Signed-off-by: NBarry Song <Baohua.Song@csr.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

rtc-opal driver provides support for rtc alarms via
timed-power-on(tpo). However some Power platforms like BML use a fake
rtc clock and don't support tpo. Such platforms are indicated by the
missing 'has-tpo' property in the device tree.

Current implementation however enables callback for
rtc_class_ops.read/set alarm irrespective of the tpo support from the
platform. This results in a failed opal call when kernel tries to read
an existing alarms via opal_get_tpo_time during rtc device registration.

This patch fixes this issue by setting opal_rtc_ops.read/set_alarm
callback pointers only when tpo is supported.
Acked-by: NMichael Neuling <mikey@neuling.org>
Acked-by: NNeelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: NVaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: NStewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Add driver for the RTC found on NXP LPC178x/18xx/408x/43xx devices.
The RTC provides calendar and clock functionality together with
alarm interrupt support.
Signed-off-by: NJoachim Eastwood <manabian@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Document NXP LPC178x/18xx/408x/43xx bindings
Signed-off-by: NJoachim Eastwood <manabian@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

platform_driver does not need to set an owner because
platform_driver_register() will set it.
Signed-off-by: NAlexandre 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: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: NAlexandre 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: NAndrea Scian <andrea.scian@dave.eu>
Signed-off-by: NAlexandre 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: NAndrea Scian <andrea.scian@dave.eu>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Along with DT support, this patch also cleans up the unnecessary
code around 'rtc_wakeup' initialization.
Signed-off-by: NChao Xie <chao.xie@marvell.com>
Signed-off-by: NVaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

removing below static analysis error:
(error) Possible null pointer dereference: client

if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
							^^^^^^^
Error comes because client is dereferenced before NULL check.
So probably NULL this check is not required.
Signed-off-by: NManinder Singh <maninder1.s@samsung.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

Use module_platform_driver for drivers whose init and exit functions
only register and unregister, respectively.

A simplified version of the Coccinelle semantic patch that performs
this transformation is as follows:

@a@
identifier f, x;
@@
-static f(...) { return platform_driver_register(&x); }

@b depends on a@
identifier e, a.x;
@@
-static e(...) { platform_driver_unregister(&x); }

@c depends on a && b@
identifier a.f;
declarer name module_init;
@@
-module_init(f);

@d depends on a && b && c@
identifier b.e, a.x;
declarer name module_exit;
declarer name module_platform_driver;
@@
-module_exit(e);
+module_platform_driver(x);
Signed-off-by: NVaishali Thakkar <vthakkar1994@gmail.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>

With the recent pinctrl-single changes, SoCs such as Texas
Instrument's OMAP processors can treat wake-up events from deeper idle
states as interrupts.

Let's add support for the optional second interrupt for wake-up using
the generic wakeirq support added in commit 4990d4fe ("PM /
Wakeirq: Add automated device wake IRQ handling")

Finally, to pass the wake-up interrupt in the dts file,
interrupts-extended property needs to be passed.

This is similar in approach to commit 2a0b965c ("serial: omap: Add
support for optional wake-up") + ee83bd3b ("serial: omap: Switch
wake-up interrupt to generic wakeirq")
Signed-off-by: NNishanth Menon <nm@ti.com>
Reviewed-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Acked-by: NTony Lindgren <tony@atomide.com>
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>