CONFIG_RTC_HCTOSYS allows the kernel to read the system time from the RTC
at boot and resume, avoiding the need for userspace to do so.
Unfortunately userspace currently has no way to know whether this
configuration option is enabled and thus cannot sensibly choose whether to
run hwclock itself or not.  Add a hctosys sysfs attribute which indicates
whether a given RTC set the system clock.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
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>

Fix two new-ish runtime warnings in the at91rm9200 (etc) RTC:

 Platform driver 'at91_rtc' needs updating - please use dev_pm_ops
 	... by just switching

 IRQ 1/at91_rtc: IRQF_DISABLED is not guaranteed on shared IRQs
 	... no longer needed now that rtc_update_irq() changed

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

Error handling code following a kzalloc should free the allocated data.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/

)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: David Brownell <david-b@pacbell.net>
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>

This code is not executed before ds1307->rtc has been successfully
initialized to the result of calling rtc_device_register.  Thus the test
that ds1307->rtc is not NULL is always true.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/

)

// <smpl>
@match exists@
expression x, E;
statement S1, S2;
@@

x = rtc_device_register(...)
... when != x = E
(
*  if (x == NULL || ...) S1 else S2
|
*  if (x == NULL && ...) S1 else S2
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
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>

[ospite@studenti.unina.it: get pcap data from the parent device]
Signed-off-by: guiming zhuo <gmzhuo@gmail.com>
Signed-off-by: Daniel Ribeiro <drwyrm@gmail.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Antonio Ospite <ospite@studenti.unina.it>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add support for RTC on the Freescale STMP37xx/378x platform.

Signed-off-by: dmitry pervushin <dpervushin@embeddedalley.com>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The Blackfin RTC IRQ is an internal interrupt, so it makes no sense to
have it be shared.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds a driver for the RTC COH 901 331 found in the ST-Ericsson U300
series mobile platforms to the RTC subsystem.  It integrates to the ARM
kernel support recently added to RMKs ARM tree and will be enabled in the
U300 defconfig in due time.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This adds a driver for Freescale's MXC internal real time clock modules.

The code is taken from Freescale's BSPs, but modified to fit the current
kernel coding mechanisms.  Also, the PMIC external clock function was
removed for now to not add dead bits and keep the code as simple as
possible.

[akpm@linux-foundation.org: make PIE_BIT_DEF[] static]
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Daniel Mack <daniel@caiaq.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off: Chris Verges <chrisv@cyberswitching.com>
Cc: Christian Pellegrin <chripell@fsfe.org>
Cc: 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>

Add support for the Philips/NXP PCF2123 RTC.

Signed-off: Chris Verges <chrisv@cyberswitching.com>
Tested-by: Chris Verges <chrisv@cyberswitching.com>
Signed-off: Christian Pellegrin <chripell@fsfe.org>
Tested-by: Christian Pellegrin <chripell@fsfe.org>
Cc: 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>

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>

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

This adds support for the RTC found inside the AB3100 Mixed Signal chip.
The symbols used for communicating with the chip is found in the
mfd/ab3100-core.c driver that also provides the platform device.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Alessandro Zummo <alessandro.zummo@towertech.it>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

The WM831x series of PMICs contain RTC functionality. The hardware
provides a 32 bit counter incrementing at 1Hz together with a per
tick interrupt and an alarm value. For simplicity the driver chooses
to define the epoch for the counter as the Unix epoch - if required
platform data can be used in future to customise this.

When powered on from a completely cold state the RTC reports that it
has not been configured - when this happens an error is returned
when attempting to read the RTC in order to avoid use of values we
know to be invalid.

The hardware also provides security features which mean that it can
ignore attempts to set the RTC time in certain circumstances, most
notably if the RTC is written to too often. These errors are detected
by verifying the written RTC value.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

Due to problems at cam.org, my nico@cam.org email address is no longer
valid.  FRom now on, nico@fluxnic.net should be used instead.

Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Remove the following warning:
Platform driver 'sa1100-rtc' needs updating - please use dev_pm_ops

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>

Remove the following warning:
Platform driver 'pxa-rtc' needs updating - please use dev_pm_ops

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>

With the reordered init order, the rtc device is not registered until
later, while sh_rtc_irq_set_freq() was attempting to assign ->irq_freq
directly, resulting in an oops. This is handled by the upper layers for
us, so just kill off the problematic dereference completely.

Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

There were a few stray unused variables left over, kill them off.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

- simplifies irq set freq
- ioctl() was duplicating functionalities of rtc-dev core
- corrected initialization sequence
- use platform_driver_probe

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Angelo Castello <angelo.castello@st.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Jamie Lenehan <lenehan@twibble.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

- removed spinlock protection, it's handled by the rtc class
- use platform_driver_probe
- return appropriate code for rtc_read_time
- style issues

Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

rtc-cmos has two drivers, one PNP and one platform.  When PNP has not
succeeded probing, platform is registered.  However, it tries to
unregister both drivers unconditionally, instead of only unregistering
those that were successfully registered.  This causes runtime warnings to
be emitted from the driver core code.

Fix this with a boolean variable for each driver indicating whether
registering was successful.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Bjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Alessandro Zummo <alessandro.zummo@towertech.it>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Brownell <david-b@pacbell.net>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Greg KH <greg@kroah.com>
Cc: Ozan Caglayan <ozan@pardus.org.tr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When i2c_smbus_read_byte_data fails in ds1374_work, we forgot to unlock
the held lock.  Fix that.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Scott Wood <scottwood@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Yoichi Yuasa <yuasa@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

Make sure we do not actually request the RTC IRQ until the device driver
is fully ready to handle and process any interrupt.  This way a spurious
interrupt won't crash the system (which may happen if the bootloader was
poking the RTC right before booting Linux).

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The rtc_update_irq() might be called with irqs enabled, if a interrupt
handler was registered without IRQF_DISABLED.  Use
spin_lock_irqsave/spin_unlock_irqrestore instead of spin_lock/spin_unlock.

Also update kerneldoc and drivers which do extra work to follow the
current interface spec, as suggestted by David Brownell.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: 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>

IRQF_SHARED should not be used with IRQF_DISABLED.  There is no in-tree
user of this driver and only out-of-tree user I know uses a dedicated irq
line for this RTC.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: 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>

IRQF_SHARED should not be used with IRQF_DISABLED.  This RTC have a
dedicated irq line to SoC's internal interrupt controller so there is
no reason to use IRQF_SHARED.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: 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>

Add support for the Epson RX-8025SA/NB RTC chips.  It includes support for
alarms, periodic interrupts (1 Hz) and clock precision adjustment.

For clock precision adjustment, the SYSFS file "clock_adjust_ppb" gets
created in "/sys/class/rtc/rtcX/device".  It permits to set and get the
clock adjustment in ppb (parts per billion), e.g.:

  # echo -183000 > /sys/class/rtc/rtc0/device/clock_adjust_ppb
  # cat /sys/class/rtc/rtc0/device/clock_adjust_ppb
  -183000

This allows to compensate temperature dependent clock drifts.  According
to the RX8025 SA/NB application manual the frequency and temperature
characteristics can be approximated using the following equation:

  df = a * (ut - t)**2

  df: Frequency deviation in any temperature
  a : Coefficient = (-35 +-5) * 10**-9
  ut: Ultimate temperature in degree = +25 +-5 degree
  t : Any temperature in degree

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Sergei Poselenov <sposelenov@emcraft.com>
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Dmitry Rakhchev <rda@emcraft.com>
Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-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>

Add ds3231 variant.  For that, the BBSQI bit position was changed from a
simple define into a lookup-array as it differs.  This also removes
writing to an unused bit in case of the ds1337.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Extend the ds1307 driver to support ds1388 too.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-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>

The RTC driver for ds1742 / ds1743 uses a static nvram attribute.  This
patch replaces this static attribute with one nvram attribute for each
ds174x registered.

The nvram size is not the same for all types of ds174x.  The nvram size is
accessible as the file size of the nvram attribute in sysfs.  With only a
single nvram attribute, this file size will be incorrect if more than one
type of ds174x is present on a system.  See the comment in the removed
code below.

This patch have been tested with linux-2.6.28 and linux-2.6.29-rc5/6 on a
custom board with one ds1743.

Signed-off-by: Torsten Ertbjerg Rasmussen <ertbjerg@gmail.com>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
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>

I found the PrimeCell/AMBA Bus drivers distrusting the resource
passed in as part of the struct amba_device abstraction. This
patch removes all hard coded resource sizes found in the PrimeCell
drivers and move the responsibility of this definition back to
the platform/board device definition, which already exist and
appear to be correct for all in-tree users of these drivers.
We do this using the resource_size() inline function which was
also replicated in the only driver using the resource size, so
that has been changed too. The KMI_SIZE was left in kmi.h in case
someone likes it. Test-compiled against Versatile and Integrator
defconfigs, seems to work but I don't posess these boards and
cannot test them.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The second argument of the probe method points to the amba_id
structure, so it's better passed with the correct type. None of the
current in-tree drivers uses the pointer, so they have only been
checked for a clean compile.

Change suggested by Russell King.

Signed-off-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This patch enables the alarm interrupt of TWL4030 RTC to wake up the
system from suspend. You can test this patch with following command.

# echo +10 > /sys/class/rtc/rtc0/wakealarm; echo mem > /sys/power/state;

Signed-off-by: Kim Kyuwon <q1.kim@samsung.com>
Acked-by: David Brownell <david-b@pacbell.net>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
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>

This adds rtc-generic support for SUPERH32.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Update the rtc-ep93xx driver to use ioremap'ed addresses.

This removes the dependency on <mach/hardware.h> and properly
reports the memory addresses used by the driver in /proc/iomem.

In addition, ep93xx_rtc_init() is updated to use
platform_driver_probe() instead of platform_driver_register().

Also, the device_create_file() calls are now properly checked for
error conditions.  The created sysfs files are also now removed
when the driver is removed.

The version number for the driver has been bumped at the request
of Alessandro Zummo.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

With no IRQ available/defined, RTC-CMOS driver prints something like:
	rtc0: alarms up to one no, y3k, 114 bytes nvram
                              ^^^^
I guess the following is a bit easier to understand:
	rtc0: no alarms, y3k, 114 bytes nvram

Signed-off-by: Krzysztof Halasa <khc@pm.waw.pl>
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>