From: Alexandre Belloni <alexandre.belloni@bootlin.com>
Date: Sat, 14 Dec 2019 23:02:44 +0100
Subject: rtc: Document RTC_VL_READ and RTC_VL_CLR ioctls
Git-commit: 790a19f18a70bf1e30b6b4d00559e1bb8a3f7e23
Patch-mainline: v5.6-rc1
References: jsc#SLE-12251
RTC_VL_READ and RTC_VL_CLR have been introduced in 2012 with commit
0f20b767e20a ("drivers/rtc/rtc-pcf8563.c: add RTC_VL_READ/RTC_VL_CLR ioctl
feature")
Document them now that they have been unified.
Link: https://lore.kernel.org/r/20191214220259.621996-3-alexandre.belloni@bootlin.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>
---
Documentation/ABI/testing/rtc-cdev | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/Documentation/ABI/testing/rtc-cdev b/Documentation/ABI/testing/rtc-cdev
index 97447283f13b..25910c3c3d7e 100644
--- a/Documentation/ABI/testing/rtc-cdev
+++ b/Documentation/ABI/testing/rtc-cdev
@@ -33,6 +33,14 @@ Description:
Requires a separate RTC_PIE_ON call to enable the periodic
interrupts.
+ * RTC_VL_READ: Read the voltage inputs status of the RTC when
+ supported. The value is a bit field of RTC_VL_*, giving the
+ status of the main and backup voltages.
+
+ * RTC_VL_CLEAR: Clear the voltage status of the RTC. Some RTCs
+ need user interaction when the backup power provider is
+ replaced or charged to be able to clear the status.
+
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
--
2.26.2