auxdisplay: charlcd: Extract character LCD core from misc/panel

Extract the character LCD core from the Parallel port LCD/Keypad Panel
driver in the misc subsystem, and convert it into a subdriver in the
auxdisplay subsystem.  This allows the character LCD core to be used by
other drivers later.

Compilation is controlled by its own Kconfig symbol CHARLCD, which is to
be selected by its users, but can be enabled manually for
compile-testing.

All functions changed their prefix from "lcd_" to "charlcd_", and gained
a "struct charlcd *" parameter to operate on a specific instance.
While the driver API thus is ready to support multiple instances, the
current limitation of a single display (/dev/lcd has a single misc minor
assigned) is retained.

No functional changes intended.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: geertu

drivers/auxdisplay/Kconfig

@@ -13,6 +13,9 @@ menuconfig AUXDISPLAY
 
 	  If you say N, all options in this submenu will be skipped and disabled.
 
+config CHARLCD
+	tristate "Character LCD core support" if COMPILE_TEST
+
 if AUXDISPLAY
 
 config KS0108

drivers/auxdisplay/Makefile

@@ -2,6 +2,7 @@
 # Makefile for the kernel auxiliary displays device drivers.
 #
 
+obj-$(CONFIG_CHARLCD)		+= charlcd.o
 obj-$(CONFIG_KS0108)		+= ks0108.o
 obj-$(CONFIG_CFAG12864B)	+= cfag12864b.o cfag12864bfb.o
 obj-$(CONFIG_IMG_ASCII_LCD)	+= img-ascii-lcd.o