linux-toradex.git/drivers/rtc/rtc-ds1307.c, branch v2.6.34-rc1

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

rtc: rtc-ds1307 add ds3231

2009-06-18T20:03:43+00:00

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

rtc: rtc-ds1307 add ds1388

2009-06-18T20:03:43+00:00

Extend the ds1307 driver to support ds1388 too.

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

rtc: add EPSON RX8025 support to DS1307 RTC driver

2009-04-01T15:59:25+00:00

Add support for the EPSON RX8025 RTC.  The date/time registers of this
chip are compatible with the DS1307.

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

rtc-ds1307: true SMBus compatibility

2009-04-01T15:59:25+00:00

Allow the rtc-ds1307 driver to work with SMBus controllers like nforce2
that do not support i2c block transfers.

Signed-off-by: Ed Swierk 
Acked-by: Jean Delvare 
Acked-by: David Brownell 
Cc: Alessandro Zummo 
Cc: BARRE Sebastien 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc-ds1307: remove legacy probe() checks

2009-01-08T16:31:00+00:00

Remove RTC register value checks from the rtc-ds1307 probe() function.
They were left over from the legacy style I2C driver, which had to defend
against finding a non-RTC chip when the driver was probed.

Also fix a minor glitch in the alarm support: DS1307 chips don't have
alarms, so name those methods after one of the chips which actually *do*
have alarms (DS1337).

Signed-off-by: Jüri Reitel 
Signed-off-by: David Brownell 
Cc: Sebastien Barre 
Cc: Alessandro Zummo 
Acked-by: Jean Delvare 
Cc: Rodolfo Giometti 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc-ds1307: SMBus compatibility

2009-01-08T16:30:59+00:00

Change i2c access functions to SMBus access functions in order to use the
ds1307 with SMBus adapter.

Signed-off-by: Sebastien Barre 
Acked-by: David Brownell 
Tested-by: David Brownell 
Acked-by: Alessandro Zummo 
Acked-by: Jean Delvare 
Cc: Rodolfo Giometti 
Tested-by: Sebastien Barre 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds