Merge tag 'rtc-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux

Pull RTC updates from Alexandre Belloni:
 "Not much this cycle. I've pushed the at32ap700x removal late but it is
  unlikely to cause any issues.

  Summary:

  Subsystem:
   - Move ABI documentation to Documentation/ABI

  New driver:
   - NXP i.MX53 SRTC
   - Chrome OS EC RTC

  Drivers:
   - Remove at32ap700x
   - Many fixes in various error paths"

* tag 'rtc-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux:
  rtc: remove rtc-at32ap700x
  Documentation: rtc: move iotcl interface documentation to ABI
  Documentation: rtc: add sysfs file permissions
  Documentation: rtc: move sysfs documentation to ABI
  rtc: mxc_v2: remove __exit annotation
  rtc: mxc_v2: Remove unnecessary platform_get_resource() error check
  rtc: add mxc driver for i.MX53 SRTC
  dt-bindings: rtc: add bindings for i.MX53 SRTC
  rtc: r7301: Fix a possible sleep-in-atomic bug in rtc7301_set_time
  rtc: r7301: Fix a possible sleep-in-atomic bug in rtc7301_read_time
  rtc: omap: fix unbalanced clk_prepare_enable/clk_disable_unprepare
  rtc: ac100: Fix multiple race conditions
  rtc: sun6i: ensure rtc is kfree'd on error
  rtc: cros-ec: add cros-ec-rtc driver.
  mfd: cros_ec: Introduce RTC commands and events definitions.
  rtc: stm32: Fix copyright
  rtc: Remove unused RTC_DEVICE_NAME_SIZE
  rtc: r9701: Remove r9701_remove function
  rtc: brcmstb-waketimer: fix error handling in brcmstb_waketmr_probe()

4 files changed, 152 insertions, 79 deletions

diff --git a/Documentation/ABI/testing/rtc-cdev b/Documentation/ABI/testing/rtc-cdev
new file mode 100644
index 000000000000..97447283f13b
--- /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/ABI/testing/sysfs-class-rtc b/Documentation/ABI/testing/sysfs-class-rtc
new file mode 100644
index 000000000000..cf60412882f0
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-rtc
@@ -0,0 +1,91 @@
+What:		/sys/class/rtc/
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		The rtc/ class subdirectory belongs to the RTC subsystem.
+
+What:		/sys/class/rtc/rtcX/
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		The /sys/class/rtc/rtc{0,1,2,3,...} directories correspond
+		to each RTC device.
+
+What:		/sys/class/rtc/rtcX/date
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RO) RTC-provided date in YYYY-MM-DD format
+
+What:		/sys/class/rtc/rtcX/hctosys
+Date:		September 2009
+KernelVersion:	2.6.32
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RO) 1 if the RTC provided the system time at boot via the
+		CONFIG_RTC_HCTOSYS kernel option, 0 otherwise
+
+What:		/sys/class/rtc/rtcX/max_user_freq
+Date:		October 2007
+KernelVersion:	2.6.24
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RW) The maximum interrupt rate an unprivileged user may request
+		from this RTC.
+
+What:		/sys/class/rtc/rtcX/name
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RO) The name of the RTC corresponding to this sysfs directory
+
+What:		/sys/class/rtc/rtcX/since_epoch
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RO) RTC-provided time as the number of seconds since the epoch
+
+What:		/sys/class/rtc/rtcX/time
+Date:		March 2006
+KernelVersion:	2.6.17
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RO) RTC-provided time in 24-hour notation (hh:mm:ss)
+
+What:		/sys/class/rtc/rtcX/*/nvmem
+Date:		February 2016
+KernelVersion:	4.6
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RW) The non volatile storage exported as a raw file, as
+		described in Documentation/nvmem/nvmem.txt
+
+What:		/sys/class/rtc/rtcX/offset
+Date:		February 2016
+KernelVersion:	4.6
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RW) The amount which the rtc clock has been adjusted in
+		firmware. Visible only if the driver supports clock offset
+		adjustment. The unit is parts per billion, i.e. The number of
+		clock ticks which are added to or removed from the rtc's base
+		clock per billion ticks. A positive value makes a day pass more
+		slowly, longer, and a negative value makes a day pass more
+		quickly.
+
+What:		/sys/class/rtc/rtcX/wakealarm
+Date:		February 2007
+KernelVersion:	2.6.20
+Contact:	linux-rtc@vger.kernel.org
+Description:
+		(RW) The time at which the clock will generate a system wakeup
+		event. This is a one shot wakeup event, so must be reset after
+		wake if a daily wakeup is required. Format is seconds since the
+		epoch by default, or if there's a leading +, seconds in the
+		future, or if there is a leading +=, seconds ahead of the
+		current alarm.
diff --git a/Documentation/devicetree/bindings/rtc/rtc-mxc_v2.txt b/Documentation/devicetree/bindings/rtc/rtc-mxc_v2.txt
new file mode 100644
index 000000000000..79d7e87b0d91
--- /dev/null
+++ b/Documentation/devicetree/bindings/rtc/rtc-mxc_v2.txt
@@ -0,0 +1,17 @@
+* i.MX53 Secure Real Time Clock (SRTC)
+
+Required properties:
+- compatible: should be: "fsl,imx53-rtc"
+- reg: physical base address of the controller and length of memory mapped
+  region.
+- clocks: should contain the phandle for the rtc clock
+- interrupts: rtc alarm interrupt
+
+Example:
+
+rtc@53fa4000 {
+	compatible = "fsl,imx53-rtc";
+	reg = <0x53fa4000 0x4000>;
+	interrupts = <24>;
+	clocks = <&clks IMX5_CLK_SRTC_GATE>;
+};
diff --git a/Documentation/rtc.txt b/Documentation/rtc.txt
index c0c977445fb9..a129acf38537 100644
--- a/Documentation/rtc.txt
+++ b/Documentation/rtc.txt
@@ -136,82 +136,5 @@ a high functionality RTC is integrated into the SOC.  That system might read
 the system clock from the discrete RTC, but use the integrated one for all
 other tasks, because of its greater functionality.
 
-SYSFS interface
----------------
-
-The sysfs interface under /sys/class/rtc/rtcN provides access to various
-rtc attributes without requiring the use of ioctls. All dates and times
-are in the RTC's timezone, rather than in system time.
-
-================ ==============================================================
-date  	   	 RTC-provided date
-hctosys   	 1 if the RTC provided the system time at boot via the
-		 CONFIG_RTC_HCTOSYS kernel option, 0 otherwise
-max_user_freq	 The maximum interrupt rate an unprivileged user may request
-		 from this RTC.
-name		 The name of the RTC corresponding to this sysfs directory
-since_epoch	 The number of seconds since the epoch according to the RTC
-time		 RTC-provided time
-wakealarm	 The time at which the clock will generate a system wakeup
-		 event. This is a one shot wakeup event, so must be reset
-		 after wake if a daily wakeup is required. Format is seconds
-		 since the epoch by default, or if there's a leading +, seconds
-		 in the future, or if there is a leading +=, seconds ahead of
-		 the current alarm.
-offset		 The amount which the rtc clock has been adjusted in firmware.
-		 Visible only if the driver supports clock offset adjustment.
-		 The unit is parts per billion, i.e. The number of clock ticks
-		 which are added to or removed from the rtc's base clock per
-		 billion ticks. A positive value makes a day pass more slowly,
-		 longer, and a negative value makes a day pass more quickly.
-*/nvmem		 The non volatile storage exported as a raw file, as described
-		 in Documentation/nvmem/nvmem.txt
-================ ==============================================================
-
-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.