serial: Add support for UART on VIA VT8500 and compatibles

This adds a driver for the serial ports found in VIA and WonderMedia
Systems-on-Chip. Interrupt-driven FIFO operation is implemented.
The hardware also supports pure register-based operation (which is
slower) and DMA-based FIFO operation. As the FIFOs are only 16 bytes
long, DMA operation is probably not worth the hassle.

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/serial/Kconfig

@@ -1381,6 +1381,16 @@ config SERIAL_MSM_CONSOLE
 	depends on SERIAL_MSM=y
 	select SERIAL_CORE_CONSOLE
 
+config SERIAL_VT8500
+	bool "VIA VT8500 on-chip serial port support"
+	depends on ARM && ARCH_VT8500
+	select SERIAL_CORE
+
+config SERIAL_VT8500_CONSOLE
+	bool "VIA VT8500 serial console support"
+	depends on SERIAL_VT8500=y
+	select SERIAL_CORE_CONSOLE
+
 config SERIAL_NETX
 	tristate "NetX serial port support"
 	depends on ARM && ARCH_NETX

drivers/serial/Makefile

@@ -86,6 +86,7 @@ obj-$(CONFIG_SERIAL_TIMBERDALE)	+= timbuart.o
 obj-$(CONFIG_SERIAL_GRLIB_GAISLER_APBUART) += apbuart.o
 obj-$(CONFIG_SERIAL_ALTERA_JTAGUART) += altera_jtaguart.o
 obj-$(CONFIG_SERIAL_ALTERA_UART) += altera_uart.o
+obj-$(CONFIG_SERIAL_VT8500) += vt8500_serial.o
 obj-$(CONFIG_SERIAL_MRST_MAX3110)	+= mrst_max3110.o
 obj-$(CONFIG_SERIAL_MFD_HSU)	+= mfd.o
 obj-$(CONFIG_SERIAL_OMAP) += omap-serial.o

include/linux/serial_core.h

@@ -199,6 +199,9 @@
 /* TI OMAP-UART */
 #define PORT_OMAP	96
 
+/* VIA VT8500 SoC */
+#define PORT_VT8500	97
+
 #ifdef __KERNEL__
 
 #include <linux/compiler.h>