Add support for the MAX6902 SPI RTC chip.  Tested on a pxa2xx cpu.

The compulab code comes from the kernel patch the produce for their
cn-x255 board. (inside a zip file on the
http://www.compulab.co.il/x255/html/x255-developer.htm)

The original file (drivers/char/max6902.c) was GPL, which is of course
an appropriate licence:

/*
 * max6902.c
 *
 * Driver for MAX6902 RTC
 *
 * Copyright (C) 2004 Compulab Ltd.
 *
 *
 * 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.
 *
 *
 */

For reference, you can get the original file here:
http://raph.people.8d.com/misc/max6902.c

[akpm@osdl.org: cleanups]
Signed-off-by: NRaphael Assenat <raph@raphnet.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Centralize CAP_SYS_XXX checks to avoid duplicate code and missing checks in
the drivers.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Remove commented capability checks and add some others.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A port of the driver for the pcf8583 i2c rtc controller to the generic RTC
framework by Alessandro Zummo.  Based on
drivers/acorn/char/{pcf8583.[hc],i2c.c}.  Hopefully, acorn can be converted
too to use this driver in the future.
Signed-off-by: NG. Liakhovetski <gl@dsa-ac.de>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Import genrtc's RTC UIE emulation (CONFIG_GEN_RTC_X) to rtc-dev driver with
slight adjustments/refinements.  This makes UIE-less rtc drivers work
better with programs doing read/poll on /dev/rtc, such as hwclock.  This
emulation should not harm rtc drivers with UIE support, since
rtc_dev_ioctl() calls underlaying rtc driver's ioctl() first.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is an "RTC-framework" driver for DS1307 and similar RTC chips,

It should be a full replacement for the existing ds1337.c driver (using the
older RTC glue), giving a net increase in the number of RTC chips that work
out-of-the-box.  There's a whole cluster of RTCs that are very similar, but
the 1337 driver was a bit too picky to work with most of them.

Still no support for RTC alarm IRQs (on chips that support them).
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJames Chapman <jchapman@katalix.com>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add a driver for the ARM PL031 RTC found on some ARM SOCs.  The driver is
fairly trivial as the RTC only provides a read/write and alarm capability.

[akpm@osdl.org: compile fix]
Signed-off-by: NDeepak <dsaxena@plexity.net>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

From: Andrew Morton <akpm@osdl.org>

drivers/rtc/rtc-m48t86.c: In function `m48t86_rtc_read_time':
drivers/rtc/rtc-m48t86.c:51: error: structure has no member named `ia64_mv'
drivers/rtc/rtc-m48t86.c:55: error: structure has no member named `ia64_mv'
drivers/rtc/rtc-m48t86.c:56: error: structure has no member named `ia64_mv'
drivers/rtc/rtc-m48t86.c:57: error: structure has no member named `ia64_mv'
drivers/rtc/rtc-m48t86.c:58: error: structure has no member named `ia64_mv'
drivers/rtc/rtc-m48t86.c:60: error: structure has no member named `ia64_mv'

readb() and writeb() are macros on ia64.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Appropriately use -ENOIOCTLCMD and -ENOTTY when the ioctl is not
implemented by a driver.

(akpm: we're not allowed to return -ENOIOCTLCMD to userspace.  This patch does
the right thing).
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix:
drivers/rtc/rtc-sa1100.c: In function `sa1100_rtc_proc':
drivers/rtc/rtc-sa1100.c:298: warning: unsigned int format, long unsigned int arg (arg 3)

and arrange for sa1100_rtc_open() to pass the devid to free_irq()
rather than NULL.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Make rtc-dev work well on 64-bit platforms with 32-bit userland.  On those
platforms, users might try to read 32-bit integer value.  This patch make
rtc-dev's read() work well for both "int" and "long" size.  This tweak is came
from genrtc driver.
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Clean up kconfig entry for the rtc-vr41xx.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch updates VR4100 series RTC driver.

* This driver supports new RTC subsystem.
* Simple set time/read time test worked fine.
Signed-off-by: NYoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- convert printks to dev_xxx

- remove messages in excess
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Move registration error message from drivers to core.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix sysfs show() return code
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Move the "24hr: yes" proc output from drivers to rtc proc code.  This is
required because the time value in the proc output is always in 24hr mode
regardless of the driver.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

- fix whitespace

- remove some debugging in excess
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix sysfs show() return code
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

 - removed a duplicate error message
 - bumped driver version
 - removed some debugging messages in excess
 - refined the formatting
 - adjusted copyright notice
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

* Always enable the oscillator when we set the time
* If the oscillator is disable when we probe the RTC report back a warning
  to the user
* Added sysfs attribute to represent the state of the oscillator
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add a driver for the ST M48T86 / Dallas DS12887 RTC.

This is a platform driver.  The platform device must provide I/O routines to
access the RTC.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add an RTC subsystem driver for the ARM SA1100/PXA2XX processor RTC.
Signed-off-by: NRichard Purdie <rpurdie@rpsys.net>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds a driver for the RTC embedded in the Cirrus Logic EP93XX
family of processors.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

RTC class aware driver for the Ricoh RS5C372 chip used, among others, on the
Synology DS101.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

An RTC class aware driver for the Philips PCF8563 RTC and Epson RTC8564 chips.

This chip is used on the Iomega NAS100D.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Driver for the Dallas/Maxim DS1672 chip, found on the Loft
(http://www.giantshoulderinc.com).
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Interrupts can be generated by

echo "alarm|tick|update" >/sys/class/rtc/rtcX/device/irq
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A port of the existing x1205 driver under the new RTC subsystem.

It is actually under test within the NSLU2 project
(http://www.nslu2-linux.org) and it is working quite well.

It is the first driver under this new subsystem and should be used as a guide
to port other drivers.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add the dev interface to the RTC subsystem.

Each RTC will be available under /dev/rtcX .  A symlink from /dev/rtc0 to
/dev/rtc cab be obtained with the following udev rule:

KERNEL=="rtc0", SYMLINK+="rtc"
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add the proc interface to the RTC subsystem.

The first RTC driver which registers with the class will be accessible by
/proc/driver/rtc .

This is required for compatibility with the standard RTC driver and to avoid
breaking any user space application which may erroneusly rely on this.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the sysfs interface to the RTC subsystem.

Each RTC client will have his own entry under /sys/classs/rtc/rtcN .

Within this entry some attributes are exported by the subsystem, like date and
time.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add the basic RTC subsystem infrastructure to the kernel.

rtc/class.c - registration facilities for RTC drivers
rtc/interface.c - kernel/rtc interface functions
rtc/hctosys.c - snippet of code that copies hw clock to sw clock
		at bootup, if configured to do so.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

RTC and date/time related functions.
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>