char/genrtc: remove powerpc support

PowerPC is the last architecture using the GEN_RTC driver on some
machines, but we can migrate them all to using the RTC_DRV_GENERIC
driver instead now.

This moves over the CONFIG_GEN_RTC option from drivers/char into
arch/powerpc/platforms/Kconfig and makes it just select the
replacement driver instead, for the only reason of not breaking
existing defconfig and .config files that users may have.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

arch/powerpc/platforms/Kconfig

@@ -321,6 +321,17 @@ config OF_RTC
 	  Uses information from the OF or flattened device tree to instantiate
 	  platform devices for direct mapped RTC chips like the DS1742 or DS1743.
 
+config GEN_RTC
+	bool "Use the platform RTC operations from user space"
+	select RTC_CLASS
+	select RTC_DRV_GENERIC
+	help
+	  This option provides backwards compatibility with the old gen_rtc.ko
+	  module that was traditionally used for old PowerPC machines.
+	  Platforms should migrate to enabling the RTC_DRV_GENERIC by hand
+	  replacing their get_rtc_time/set_rtc_time callbacks with
+	  a proper RTC device driver.
+
 config SIMPLE_GPIO
 	bool "Support for simple, memory-mapped GPIO controllers"
 	depends on PPC

arch/powerpc/platforms/ps3/time.c

@@ -20,9 +20,9 @@
 
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
+#include <linux/rtc.h>
 
 #include <asm/firmware.h>
-#include <asm/rtc.h>
 #include <asm/lv1call.h>
 #include <asm/ps3.h>
 

drivers/char/Kconfig

@@ -325,10 +325,10 @@ config JS_RTC
 	  To compile this driver as a module, choose M here: the
 	  module will be called js-rtc.
 
-config GEN_RTC
+config OLD_GEN_RTC
 	tristate "Generic /dev/rtc emulation"
 	depends on RTC!=y
-	depends on PPC
+	depends on BROKEN
 	---help---
 	  If you say Y here and create a character special file /dev/rtc with
 	  major number 10 and minor number 135 using mknod ("man mknod"), you

drivers/char/Makefile

@@ -25,7 +25,7 @@ obj-$(CONFIG_APPLICOM)		+= applicom.o
 obj-$(CONFIG_SONYPI)		+= sonypi.o
 obj-$(CONFIG_RTC)		+= rtc.o
 obj-$(CONFIG_HPET)		+= hpet.o
-obj-$(CONFIG_GEN_RTC)		+= genrtc.o
+obj-$(CONFIG_OLD_GEN_RTC)	+= genrtc.o
 obj-$(CONFIG_EFI_RTC)		+= efirtc.o
 obj-$(CONFIG_DS1302)		+= ds1302.o
 obj-$(CONFIG_XILINX_HWICAP)	+= xilinx_hwicap/