s3c_rtc_gettime() already returns the result of rtc_valid_tm() on the
obtained time so get rid of another call to rtc_valid_tm().
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: NChanwoo Choi <cw00.choi@samsung.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

module_platform_driver_probe() prevents driver from requesting probe
deferral.  So using module_platform_drive() to support probe deferral.
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

RTC is present in AM43xx and DRA7xx also.  Updating the Kconfig to depend
on ARCH_OMAP or ARCH_DAVINCI
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

RTC module contains a kicker mechanism to prevent any spurious writes from
changing the register values.  This mechanism requires two MMR writes to
the KICK0 and KICK1 registers with exact data values before the kicker
lock mechanism is released.

Currently the driver release the lock in the probe and leaves it enabled
until the rtc driver removal.  This eliminates the idea of preventing
spurious writes when RTC driver is loaded.  So implement rtc lock and
unlock functions before and after register writes.

This is as advised by Paul to implement lock and unlock functions in the
driver and not to unlock and leave it in probe.  The same discussion can
be seen here:
http://www.mail-archive.com/linux-omap%40vger.kernel.org/msg111588.htmlSigned-off-by: NLokesh Vutla <lokeshvutla@ti.com>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Tero Kristo <t-kristo@ti.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Initialize the device time (if it is wrong) before registering RTC device
to fix following error message during rtc-s3c probe:

[    2.215414] rtc (null): read_time: fail to read
[    2.216322] s3c-rtc 10070000.rtc: rtc core: registered s3c as rtc1
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: NChanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use function name in the error log instead of __FILE__.
Signed-off-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

__rtc_read_time logs should be debug logs instead of error logs.

For example, when the RTC clock is not set, it's not really useful
to print a kernel error log every time someone tries to read the clock:

	~ # hwclock -r
	[  604.508263] rtc rtc0: read_time: fail to read
	hwclock: RTC_RD_TIME: Invalid argument

If there's a real error, it's likely that lower level or higher level
code will tell it anyway. Make these logs debug logs, and also print
the error code for the read failure.
Signed-off-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In some error cases RTC name is used before it is initialized:

	rtc-rs5c372 0-0032: clock needs to be set
	rtc-rs5c372 0-0032: rs5c372b found, 24hr, driver version 0.6
	rtc (null): read_time: fail to read
	rtc-rs5c372 0-0032: rtc core: registered rtc-rs5c372 as rtc0

Fix by initializing the name early.
Signed-off-by: NAaro Koskinen <aaro.koskinen@iki.fi>
Acked-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The S2MPS13 RTC is almost the same as S2MPS14. The differences when
updating alarm are:
1. Set WUDR+AUDR field instead of WUDR+RUDR.
2. Clear the AUDR field later (it is not auto-cleared).
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I've noticed that most of the patches for the RTC subsystem are currently
either taken directly by Andrew or going through another maintainer's
tree, quite often without an Acked-by or Reviewed-by tag.

I'd like to propose myself as the RTC subsystem co-maintainer, to mainly
help Alessandro reviewing incoming patches and maintain a subsystem tree
to avoid having the RTC patches going through trees when they have no
particular dependencies.
Signed-off-by: NAlexandre Belloni <alexandre.belloni@free-electrons.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add driver for the RTC hardware block on the Conexant CX92755 SoC, from
the Digicolor series of SoCs.  Tested on the Equinox evaluation board for
the CX92755 chip.

[akpm@linux-foundation.org: build command arrays at compile-time]
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a device tree binding documentation to the Real Time Clock hardware
block on the Conexant CX92755 SoC.  The CX92755 is from the Digicolor SoCs
series.  Other SoCs in that series may share the same hardware block.
Signed-off-by: NBaruch Siach <baruch@tkos.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When the clock is disabled, do not return a rate of 0 but instead return
the rate the clock will be running at after it gets enabled.  This
prevents problems when the core clock code is trying to determine a
suitable rate, while the clock is still off.
Signed-off-by: NHeiko Stuebner <heiko@sntech.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Tested-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Tested-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The RTC is in a different clock domain so a quick read after write
can retrieve a mangled value of the old/new values
Signed-off-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Tested-by: NAdam Ward <adam.ward.opensource@diasemi.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix two minor sparse warnings:

  CHECK   drivers/rtc/rtc-ds1685.c
  drivers/rtc/rtc-ds1685.c:2178:1: warning: function 'ds1685_rtc_poweroff' with external linkage has definition
  drivers/rtc/rtc-ds1685.c:802:23: warning: Using plain integer as NULL pointer

Fixes: aaaf5fbf ("rtc: add driver for DS1685 family of real time clocks")
Signed-off-by: NJoshua Kinard <kumba@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The rtc driver core now sets the platform_driver 'owner' property, so
remove the assignment from the DS1685 driver.

Fixes: aaaf5fbf: "rtc: add driver for DS1685 family of real time clocks"
Signed-off-by: NJoshua Kinard <kumba@gentoo.org>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The regmap_config struct may be const because it is not modified by the
driver and regmap_init() accepts pointer to const.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The current functions in s3c-rtc driver execute clk_enable/disable() to
control clocks and some functions execute s3c_rtc_alarm_clk_enable()
unnecessarily.  So this patch deletes the duplicate clock control and
spilts s3c_rtc_alarm_clk_enable() out as
s3c_rtc_enable_clk()/s3c_rtc_disable_clk() to improve readability.
Signed-off-by: NChanwoo Choi <cw00.choi@samsung.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Kukjin Kim <kgene@kernel.org>
Cc: Inki Dae <inki.dae@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When using device trees on the ARM platform, it is not certain at compile
time whether or not the system will have a RTC.

If one enables CONFIG_HCTOSYS just in case the system booted has a RTC,
and it turns out not to be, this will result in a big fat "unable to open
rtc device" error being printed to console, even when "quiet" is set in
the kernel cmdline.

Fix this by outputting the message with loglevel info instead.
Signed-off-by: NFloris Bos <bos@je-eigen-domein.nl>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Despite its name, sign_extend32() is safe to use for 8 bit types too.
(See https://lkml.org/lkml/2015/1/18/289).
Signed-off-by: NMartin Kepplinger <martink@posteo.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Set the of_match_table for this driver so that devices can be described in
the device tree.  This device is used in the Trimslice and is already
defined in the Trimslice device tree.
Signed-off-by: NPeter Robinson <pbrobinson@gmail.com>
Cc: Mike Rapoport <mike@compulab.co.il>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The rtc's status register allows to determine if a 32k crystal is
connected to keep the rtc running in low power states provided the
corresponding fuse bits were blown correctly during production.  (In case
they were not, the right frequency can be stated in the device tree.) If
there is no such crystal available force the 24 MHz XTAL clock to keep
running to retain the right date and time.  Otherwise use the crystal to
save some power.

It would be nice to only switch to the crystal when the XTAL clock is
about to be disabled and keep the crystal off when unneeded because XTAL
is always on while the chip is powered on.  But as sudden power loss isn't
detectable this is not save.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This commit does not change any logic here.  It just makes the code easier
to read.

This is how it looked like:
If err != 0 return err;
else return 0;
Signed-off-by: NRobert Kmiec <robert.r.kmiec@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It might be annoying to constantly see this:

	scripts/Makefile.kasan:16: Cannot use CONFIG_KASAN: -fsanitize=kernel-address is not supported by compiler

while performing allmodconfig/allyesconfig build tests.
Disable this warning if CONFIG_COMPILE_TEST=y.
Signed-off-by: NAndrey Ryabinin <a.ryabinin@samsung.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

sprintf() reliably returns the number of characters printed, so we don't
need to ask strlen() where we are.  Also replace calling sprintf("%02x")
in a loop with the much simpler bin2hex().

[akpm@linux-foundation.org: it's odd to include kernel.h after everything else]
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since commit 1f65f947 ("checkpatch: add checks for question mark and
colon spacing") back in 2008, checkpatch has reported false positive for
asm volatile uses of "::" checkpatch thinks colons should always have
spaces around it.

Add an exception for colons with colons on either side for this valid asm
volatile (and c++) use.
Signed-off-by: NJoe Perches <joe@perches.com>
Reported-by: NYehuda Yitschak <yehuday@marvell.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a patch touches multiple files, the --fix and --fix-inplace option
doesn't keep the proper line count and makes the new patch file not able
to be applied via bad offset line numbers when lines are added or deleted
by the --fix option.

Dunno how that extra backslash snuck in there.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ENOSYS is the mechanism used by user code to detect whether the running
kernel implements a given system call.  It should not be returned by
anything except an unimplemented system call.

Unfortunately, it is rather frequently used in the kernel to indicate that
various new functions of existing system calls are not implemented.  This
should be discouraged.

Improve the comment in errno.h to help clarify ENOSYS's purpose.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ENOSYS means that a nonexistent system call was called.  We have a
bad habit of using it for things like invalid operations on
otherwise valid syscalls.  We should avoid this in new code.

Pervasive incorrect usage of ENOSYS came up at the kernel summit ABI
review discussion.  Let's see if checkpatch can help.

I'll submit a separate patch for include/uapi/asm-generic/errno.h.
Signed-off-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

const objects shouldn't be __read_mostly.  They are read-only.

Marking these objects as __read_mostly causes section conflicts with LTO
linking.

So add a test to try to avoid this issue.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Code such as:
       x = timercmp(&now, &end, <);
Will currently trigger a checkpatch error. e.g.

ERROR: spaces required around that '<'

This is because the "Ignore operators passed as parameters" check looks
only for a comma following the operator.  Improve the check by also
looking for a close parenthesis.
Signed-off-by: NSam Bobroff <sam.bobroff@au1.ibm.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a test for sizeof(foo)/sizeof(foo[0]) that could be ARRAY_SIZE(foo).
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add another struct to the list of normally const struct types
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are #defines with long string constants like:
	#define foo "some really long string > 80 columns"
Add a long line exception for them.

Miscellanea:

Use the $String variable for slightly better readability
Signed-off-by: NJoe Perches <joe@perches.com>
Reported-by: NMadalin-Cristian Bucur <madalin.bucur@freescale.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit messages lines are sometimes overly long.

Suggest line wrapping at 75 columns so the default git commit log
indentation of 4 plus the commit message text still fits on an 80 column
screen.

Add a checkpatch test for long commit messages lines too.
Signed-off-by: NJoe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently checkpatch warns when asm/file.h is included and linux/file.h
exists.  That conversion can be made when linux/file.h includes asm/file.h
which is not always the case.(See signal.h)
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Cc: Andy Whitcroft <apw@canonical.com>
Acked-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using 'const <type> const *' is generally meant to be written 'const
<type> * const'.

Add a test for the miswritten form.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a few conditions to the test to find
	return (ERRNO);

Make the output message a bit less cryptic too.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>