Documentation: rtc: move iotcl interface documentation to ABI
The ioctl interface should be in Documentation/ABI along with the rest
of the interfaces.
Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
diff --git a/Documentation/ABI/testing/rtc-cdev b/Documentation/ABI/testing/rtc-cdev
new file mode 100644
index 0000000..9744728
--- /dev/null
+++ b/Documentation/ABI/testing/rtc-cdev
@@ -0,0 +1,42 @@
+What: /dev/rtcX
+Date: April 2005
+KernelVersion: 2.6.12
+Contact: linux-rtc@vger.kernel.org
+Description:
+ The ioctl interface to drivers for real-time clocks (RTCs).
+ Following actions are supported:
+
+ * RTC_RD_TIME, RTC_SET_TIME: Read or set the RTC time. Time
+ format is a Gregorian calendar date and 24 hour wall clock
+ time.
+
+ * RTC_AIE_ON, RTC_AIE_OFF: Enable or disable the alarm interrupt
+ for RTCs that support alarms
+
+ * RTC_ALM_READ, RTC_ALM_SET: Read or set the alarm time for
+ RTCs that support alarms. Can be set upto 24 hours in the
+ future. Requires a separate RTC_AIE_ON call to enable the
+ alarm interrupt. (Prefer to use RTC_WKALM_*)
+
+ * RTC_WKALM_RD, RTC_WKALM_SET: For RTCs that support a more
+ powerful interface, which can issue alarms beyond 24 hours and
+ enable IRQs in the same request.
+
+ * RTC_PIE_ON, RTC_PIE_OFF: Enable or disable the periodic
+ interrupt for RTCs that support periodic interrupts.
+
+ * RTC_UIE_ON, RTC_UIE_OFF: Enable or disable the update
+ interrupt for RTCs that support it.
+
+ * RTC_IRQP_READ, RTC_IRQP_SET: Read or set the frequency for
+ periodic interrupts for RTCs that support periodic interrupts.
+ Requires a separate RTC_PIE_ON call to enable the periodic
+ interrupts.
+
+ The ioctl() calls supported by the older /dev/rtc interface are
+ also supported by the newer RTC class framework. However,
+ because the chips and systems are not standardized, some PC/AT
+ functionality might not be provided. And in the same way, some
+ newer features -- including those enabled by ACPI -- are exposed
+ by the RTC class framework, but can't be supported by the older
+ driver.
diff --git a/Documentation/rtc.txt b/Documentation/rtc.txt
index f521262..a129acf 100644
--- a/Documentation/rtc.txt
+++ b/Documentation/rtc.txt
@@ -136,50 +136,5 @@
the system clock from the discrete RTC, but use the integrated one for all
other tasks, because of its greater functionality.
-IOCTL interface
----------------
-
-The ioctl() calls supported by /dev/rtc are also supported by the RTC class
-framework. However, because the chips and systems are not standardized,
-some PC/AT functionality might not be provided. And in the same way, some
-newer features -- including those enabled by ACPI -- are exposed by the
-RTC class framework, but can't be supported by the older driver.
-
- * RTC_RD_TIME, RTC_SET_TIME ... every RTC supports at least reading
- time, returning the result as a Gregorian calendar date and 24 hour
- wall clock time. To be most useful, this time may also be updated.
-
- * RTC_AIE_ON, RTC_AIE_OFF, RTC_ALM_SET, RTC_ALM_READ ... when the RTC
- is connected to an IRQ line, it can often issue an alarm IRQ up to
- 24 hours in the future. (Use RTC_WKALM_* by preference.)
-
- * RTC_WKALM_SET, RTC_WKALM_RD ... RTCs that can issue alarms beyond
- the next 24 hours use a slightly more powerful API, which supports
- setting the longer alarm time and enabling its IRQ using a single
- request (using the same model as EFI firmware).
-
- * RTC_UIE_ON, RTC_UIE_OFF ... if the RTC offers IRQs, the RTC framework
- will emulate this mechanism.
-
- * RTC_PIE_ON, RTC_PIE_OFF, RTC_IRQP_SET, RTC_IRQP_READ ... these icotls
- are emulated via a kernel hrtimer.
-
-In many cases, the RTC alarm can be a system wake event, used to force
-Linux out of a low power sleep state (or hibernation) back to a fully
-operational state. For example, a system could enter a deep power saving
-state until it's time to execute some scheduled tasks.
-
-Note that many of these ioctls are handled by the common rtc-dev interface.
-Some common examples:
-
- * RTC_RD_TIME, RTC_SET_TIME: the read_time/set_time functions will be
- called with appropriate values.
-
- * RTC_ALM_SET, RTC_ALM_READ, RTC_WKALM_SET, RTC_WKALM_RD: gets or sets
- the alarm rtc_timer. May call the set_alarm driver function.
-
- * RTC_IRQP_SET, RTC_IRQP_READ: These are emulated by the generic code.
-
- * RTC_PIE_ON, RTC_PIE_OFF: These are also emulated by the generic code.
-
-If all else fails, check out the tools/testing/selftests/timers/rtctest.c test!
+Check out tools/testing/selftests/timers/rtctest.c for an example usage of the
+ioctl interface.
