linux-toradex.git/drivers/rtc/rtc-ds1307.c, branch v3.2.28

rtc: add initial support for mcp7941x parts

2011-11-02T23:06:58+00:00

Add initial support for the microchip mcp7941x series of real time clocks.

The mcp7941x series is generally compatible with the ds1307 and ds1337 rtc
devices from dallas semiconductor.  minor differences include a backup
battery enable bit, and the polarity of the oscillator enable bit.

Signed-off-by: David Anders 
Cc: Alessandro Zummo 
Reviewed-by: Wolfram Sang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/rtc/rtc-ds1307.c: add support for RTC device pt7c4338

2011-06-28T01:00:12+00:00

PT7C4338 chip is being manufactured by Pericom Technology Inc.  It is a
serial real-time clock which provides:

1) Low-power clock/calendar.
2) Programmable square-wave output.

It has 56 bytes of nonvolatile RAM.  Its register set is same as that of
rtc device: DS1307.

Signed-off-by: Priyanka Jain 
Acked-by: Timur Tabi 
Reviewed-by: Wolfram Sang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

RTC: Convert rtc drivers to use the alarm_irq_enable method

2011-02-03T21:02:35+00:00

Some rtc drivers use the ioctl method instead of the alarm_irq_enable
method for enabling alarm interupts. With the new virtualized RTC
rework, its important for drivers to use the alarm_irq_enable instead.

This patch converts the drivers that use the AIE ioctl method to
use the alarm_irq_enable method. Other ioctl cmds are left untouched.

I have not been able to test or even compile most of these drivers.
Any help to make sure this change is correct would be appreciated!

CC: Alessandro Zummo 
CC: Thomas Gleixner 
CC: Marcelo Roberto Jimenez 
Reported-by: Marcelo Roberto Jimenez 
Tested-by: Marcelo Roberto Jimenez 
Signed-off-by: John Stultz

i2c: Constify i2c_client where possible

2011-01-10T21:11:23+00:00

Helper functions for I2C and SMBus transactions don't modify the
i2c_client that is passed to them, so it can be marked const.

Signed-off-by: Jean Delvare

rtc: fix ds1388 time corruption

2010-06-29T22:29:31+00:00

The ds1307 driver misreads the ds1388 registers when checking for 12 or 24
hour mode.  Instead of checking the hour register it reads the minute
register.  Therefore the driver thinks minutes >= 40 has the 12HR bit set
and resets the minute register by zeroing the high bits.  This results in
minutes are reset to 0-9, jumping back in time 40 or 50 minutes.  The time
jump is also written back to the RTC.

Signed-off-by: Joakim Tjernlund 
Cc: Wan ZongShun 
Cc: Alessandro Zummo 
Cc: Paul Gortmaker 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sysfs: add struct file* to bin_attr callbacks

2010-05-21T16:37:31+00:00

This allows bin_attr->read,write,mmap callbacks to check file specific data
(such as inode owner) as part of any privilege validation.

Signed-off-by: Chris Wright 
Signed-off-by: Greg Kroah-Hartman

rtc: set wakeup capability for I2C and SPI RTC drivers

2009-12-17T23:45:32+00:00

RTC core won't allow wakeup alarms to be set if RTC devices' parent (i.e.
i2c_client or spi_device) isn't wakeup capable.

For I2C devices there is I2C_CLIENT_WAKE flag exists that we can pass via
board info, and if set, I2C core will initialize wakeup capability.  For
SPI devices there is no such flag at all.

I believe that it's not platform code responsibility to allow or disallow
wakeups, instead, drivers themselves should set the capability if a device
can trigger wakeups.

That's what drivers/base/power/sysfs.c says:

 * It is the responsibility of device drivers to enable (or disable)
 * wakeup signaling as part of changing device power states, respecting
 * the policy choices provided through the driver model.

I2C and SPI RTC devices send wakeup events via interrupt lines, so we
should set the wakeup capability if IRQ is routed.

Ideally we should also check irq for wakeup capability before setting
device's capability, i.e.

	if (can_irq_wake(irq))
		device_set_wakeup_capable(&client->dev, 1);

But there is no can_irq_wake() call exist, and it is not that trivial to
implement it for all interrupts controllers and complex/cascaded setups.

drivers/base/power/sysfs.c also covers these cases:

 * Devices may not be able to generate wakeup events from all power
 * states.  Also, the events may be ignored in some configurations;
 * for example, they might need help from other devices that aren't
 * active

So there is no guarantee that wakeup will actually work, and so I think
there is no point in being pedantic wrt checking IRQ wakeup capability.

Signed-off-by: Anton Vorontsov 
Cc: David Brownell 
Cc: Ben Dooks 
Cc: Jean Delvare 
Cc: Alessandro Zummo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc: ds1307 make it possible to share an irq

2009-12-16T15:20:00+00:00

It's possible to have RTC irq shared with other device (e.g.
mpc8349e-mitx board shares ds1339 irq with phy one).  Handle this in
driver.

Signed-off-by: Dmitry Eremin-Solenikov 
Signed-off-by: Alessandro Zummo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

drivers/rtc: correct error-handling code

2009-09-23T14:39:45+00:00

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/)

// 
@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
)
// 

Signed-off-by: Julia Lawall 
Acked-by: Wolfram Sang 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc: make rtc_update_irq callable with irqs enabled

2009-06-19T23:46:05+00:00

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 
Cc: Alessandro Zummo 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds