[PATCH] RTC class: Kconfig improvements

Small updates to make the RTC class Kconfig text be more informative.  This
should help folk used to the drivers/char/rtc.c support, or a single RTC, be
slightly less surprised by the differences.

Also, adds a new RTC_DEBUG option to predefine DEBUG in the framework and its
drivers, while debugging.  That's getting to be a standard idiom, and it's
pretty useful.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: Oleg Verych <olecom@flower.upol.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 23 insertions, 7 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 62c804af9fbe..fc766a7a611e 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -37,6 +37,13 @@ config RTC_HCTOSYS_DEVICE
           The RTC device that will be used as the source for
           the system time, usually rtc0.
 
+config RTC_DEBUG
+        bool "RTC debug support"
+        depends on RTC_CLASS = y
+        help
+          Say yes here to enable debugging support in the RTC framework
+          and individual RTC drivers.
+
 comment "RTC interfaces"
         depends on RTC_CLASS
 
@@ -45,8 +52,8 @@ config RTC_INTF_SYSFS
         depends on RTC_CLASS && SYSFS
         default RTC_CLASS
         help
-          Say yes here if you want to use your RTC using the sysfs
-          interface, /sys/class/rtc/rtcX .
+          Say yes here if you want to use your RTCs using sysfs interfaces,
+          /sys/class/rtc/rtc0 through /sys/.../rtcN.
 
           This driver can also be built as a module. If so, the module
           will be called rtc-sysfs.
@@ -56,8 +63,9 @@ config RTC_INTF_PROC
         depends on RTC_CLASS && PROC_FS
         default RTC_CLASS
         help
-          Say yes here if you want to use your RTC using the proc
-          interface, /proc/driver/rtc .
+          Say yes here if you want to use your first RTC through the proc
+          interface, /proc/driver/rtc.  Other RTCs will not be available
+          through that API.
 
           This driver can also be built as a module. If so, the module
           will be called rtc-proc.
@@ -67,8 +75,11 @@ config RTC_INTF_DEV
         depends on RTC_CLASS
         default RTC_CLASS
         help
-          Say yes here if you want to use your RTC using the dev
-          interface, /dev/rtc .
+          Say yes here if you want to use your RTCs using the /dev
+          interfaces, which "udev" sets up as /dev/rtc0 through
+          /dev/rtcN.  You may want to set up a symbolic link so one
+          of these can be accessed as /dev/rtc, which is a name
+          expected by "hwclock" and some other programs.
 
           This driver can also be built as a module. If so, the module
           will be called rtc-dev.
@@ -78,7 +89,8 @@ config RTC_INTF_DEV_UIE_EMUL
         depends on RTC_INTF_DEV
         help
           Provides an emulation for RTC_UIE if the underlaying rtc chip
-          driver did not provide RTC_UIE ioctls.
+          driver does not expose RTC_UIE ioctls.  Those requests generate
+          once-per-second update interrupts, used for synchronization.
 
 comment "RTC drivers"
         depends on RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index e72d467ab214..3ba5ff6e6800 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -2,6 +2,10 @@
 # Makefile for RTC class/drivers.
 #
 
+ifeq ($(CONFIG_RTC_DEBUG),y)
+        EXTRA_CFLAGS            += -DDEBUG
+endif
+
 obj-$(CONFIG_RTC_LIB)           += rtc-lib.o
 obj-$(CONFIG_RTC_HCTOSYS)       += hctosys.o
 obj-$(CONFIG_RTC_CLASS)         += rtc-core.o