rtc: rework rtc_register_device() resource management

rtc_register_device() is a managed interface but it doesn't use devres
by itself - instead it marks an rtc_device as "registered" and the devres
callback for devm_rtc_allocate_device() takes care of resource release.

This doesn't correspond with the design behind devres where managed
structures should not be aware of being managed. The correct solution
here is to register a separate devres callback for unregistering the
device.

While at it: rename rtc_register_device() to devm_rtc_register_device()
and add it to the list of managed interfaces in devres.rst. This way we
can avoid any potential confusion of driver developers who may expect
there to exist a corresponding unregister function.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20201109163409.24301-8-brgl@bgdev.pl

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

rtc: rs5c348: report error when time is invalid

Instead of resetting the RTC to an bogus valid time, let userspace know
that the time is invalid when XSTP is set. Reset XSTP when setting the time
again.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rtc: rs5c348: remove forward declaration

The name passed to devm_rtc_device_register is now unused. anyway, switch
to devm_rtc_allocate_device to avoid forward declaring rs5c348_driver.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rtc: rs5c348: remove useless label

Since commit 8fb1ecb36f7e ("rtc: rtc-rs5c348: use devm_*() functions") the
kfree_exit label simply returns ret.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rtc: rs5c348: let the core handle invalid time

Returning a valid time when the time is invalid is a bad practice, because
then userspace is not able to react on the information. Also, it doesn't
make sense to return epoch because it is already the default time.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

rtc: remove useless DRV_VERSION

Many drivers are defining a DRV_VERSION. This is often only used for
MODULE_VERSION and sometimes to print an info message at probe time. This
is kind of pointless as they are all versionned with the kernel anyway.
Also the core will print a message when a new rtc is found.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

spi: Drop owner assignment from spi_drivers

An spi_driver does not need to set an owner, it will be populated by the
driver core.

Signed-off-by: Andrew F. Davis <afd@ti.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/rtc/rtc-rs5c348.c: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly. This is a cosmetic change to make
the code simpler and enhance the readability.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-rs5c348.c: remove empty function

After the switch to devm_* functions and the removal of
rtc_device_unregister(), the 'remove' function does not do anything.
Delete it.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: rtc-rs5c348: use devm_*() functions

Use devm_*() functions to make cleanup paths simpler.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Drivers: rtc: remove __dev* attributes.

CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.

This change removes the use of __devinit, __devexit_p, __devinitdata,
__devinitconst, and __devexit from these drivers.

Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.

Cc: Bill Pemberton <wfp5p@virginia.edu>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode

Correct the offset by subtracting 20 from tm_hour before taking the
modulo 12.

[ "Why 20?" I hear you ask. Or at least I did.

Here's the reason why: RS5C348_BIT_PM is 32, and is - stupidly -
included in the RS5C348_HOURS_MASK define. So it's really subtracting
out that bit to get "hour+12". But then because it does things modulo
12, it needs to add the 12 in again afterwards anyway.

This code is confused. It would be much clearer if RS5C348_HOURS_MASK
just didn't include the RS5C348_BIT_PM bit at all, then it wouldn't
need to do the silly subtract either.

Whatever. It's all just math, the end result is the same. - Linus ]

Reported-by: James Nute <newten82@gmail.com>
Tested-by: James Nute <newten82@gmail.com>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: convert rtc spi drivers to module_spi_driver

Factor out some boilerplate code for spi driver registration into
module_spi_driver.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Cc: Mark Jackson <mpfj@mimc.co.uk>
Cc: Dennis Aberilla <denzzzhome@yahoo.com>
Cc: Nikolaus Voss <n.voss@weinmann.de>
Cc: "Kim B. Heino" <Kim.Heino@bluegiga.com>
Cc: Raphael Assenat <raph@raphnet.net>
Cc: Chris Verges <chrisv@cyberswitching.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/: remove redundant spi driver bus initialization

In ancient times it was necessary to manually initialize the bus field of
an spi_driver to spi_bus_type. These days this is done in
spi_driver_register(), so we can drop the manual assignment.

The patch was generated using the following coccinelle semantic patch:
// <smpl>
@@
identifier _driver;
@@
struct spi_driver _driver = {
.driver = {
- .bus = &spi_bus_type,
},
};
// </smpl>

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

rtc: Add module.h to implicit users in drivers/rtc

The module.h was implicitly everywhere, but when we clean
that up, the implicit users will compile fail; fix them up
in advance.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

spi: prefix modalias with "spi:"

This makes it consistent with other buses (platform, i2c, vio, ...). I'm
not sure why we use the prefixes, but there must be a reason.

This was easy enough to do it, and I did it.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Samuel Ortiz <sameo@openedhand.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Acked-by: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/: use bcd2bin/bin2bcd

Change drivers/rtc/ to use the new bcd2bin/bin2bcd functions instead of
the obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[PATCH] rtc: Make rtc-rs5c348 driver hotplug-aware

The rtc-rs5c348 SPI driver name doesn't match its module name, which
prevents it from properly hotplugging. There is only one in-tree user
of its driver, which is fixed by this patch too.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: David Brownell <david-b@pacbell.net>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

[PATCH] constify rtc_class_ops: update drivers

Update RTC framework so that drivers can constify their method tables, moving
them from ".data" to ".rodata". Then update the drivers.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] RTC: more XSTP/VDET support for rtc-rs5c348 driver

If the chip detected "oscillator stop" condition, show an warning message.
And initialize it with the Epoch time instead of leaving it with unknown
date/time.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

[PATCH] RTC: add rtc-rs5c348 driver

Add an SPI driver for the Ricoh RS5C348 RTC chip.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>