linux-toradex.git/Documentation/rtc.txt, branch v3.3.5

RTC: Fix up rtc.txt documentation to reflect changes to generic rtc layer

2011-03-09T19:25:10+00:00

Now that the genric RTC layer handles much of the RTC functionality,
the rtc.txt documentation needs to be updated to remove outdated information.

CC: Thomas Gleixner 
CC: Alessandro Zummo 
CC: Marcelo Roberto Jimenez 
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz

rtc: add boot_timesource sysfs attribute

2009-09-23T14:39:46+00:00

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

rtc: document the sysfs interface

2009-09-23T14:39:46+00:00

The sysfs interface to the RTC class drivers is currently undocumented.
Add some basic documentation defining the semantics of the fields.

Signed-off-by: Matthew Garrett 
Cc: Mark Brown 
Acked-by: Alessandro Zummo 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc: update documentation wrt RTC_PIE/irq_set_state

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

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

rtc: cleanup example code

2008-02-06T18:41:14+00:00

No functional changes here, just tighten up style/whitespace.

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

rtc: update documentation wrt irq_set_freq

2008-02-06T18:41:14+00:00

Document the proper use of the irq_set_freq function.

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

rtc: tweak driver documentation for rtc periodic

2007-11-15T02:45:37+00:00

The max_user_freq member is not really meant for RTC drivers to modify, so
update the rtc documentation so drivers writers know what is expected of
them when handling periodic events.

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

rtc: make example code jump to done instead of return when ioctl not supported

2007-07-17T17:23:08+00:00

Signed-off-by: Hans-Christian Egtvedt 
Cc: Haavard Skinnemoen 
Cc: David Brownell 
Cc: Alessandro Zummo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rtc: remove "RTC_ALM_SET mode" bugs

2007-05-08T18:15:19+00:00

This fixes a common glitch in how RTC drivers handle two "set alarm" modes,
by getting rid of the surprising/hidden one that was rarely implemented
correctly (and which could expose nonportable hardware-specific behavior).

The glitch comes from the /dev/rtcX logic implementing the legacy
RTC_ALM_SET (limited to 24 hours, needing RTC_AIE_ON) ioctl on top of the
RTC driver call providing access to the newer RTC_WKALM_SET (without those
limitations) by initializing the day/month/year fields to be invalid ...
that second mode.

Now, since few RTC drivers check those fields, and most hardware misbehaves
when faced with invalid date fields, many RTC drivers will set bogus alarm
times on those RTC_ALM_SET code paths.  (Several in-tree drivers have that
issue, and I also noticed it with code reviews on several new RTC drivers.)

This patch ensures that RTC drivers never see such invalid alarm fields, by
moving some logic out of rtc-omap into the RTC_ALM_SET code and adding an
explicit check (which will prevent the issue on other code paths).

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

[PATCH] some rtc documentation updates

2007-02-11T19:18:06+00:00

Fix typo when describing RTC_WKALM.  Add some helpful pointers to people
developing their own RTC driver.  Change a bunch of the error messages in the
test program to be a bit more helpful.

Signed-off-by: Mike Frysinger 
Cc: Alessandro Zummo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds