serial: sh-sci: Handle GPIO function requests.

This adds initial support for requesting the various GPIO functions
necessary for certain ports. This just plugs in dumb request/free logic,
but serves as a building block for migrating off of the ->init_pins mess
to a wholly gpiolib backed solution (primarily parts with external
RTS/CTS pins, but will also allow us to clean up RXD pin testing).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/linux/serial_sci.h b/include/linux/serial_sci.h
index 15b1bdc..7877907 100644
--- a/include/linux/serial_sci.h
+++ b/include/linux/serial_sci.h
@@ -64,6 +64,17 @@
 	SCIx_MUX_IRQ = SCIx_NR_IRQS,	/* special case */
 };
 
+/* Offsets into the sci_port->gpios array */
+enum {
+	SCIx_SCK,
+	SCIx_RXD,
+	SCIx_TXD,
+	SCIx_CTS,
+	SCIx_RTS,
+
+	SCIx_NR_FNS,
+};
+
 enum {
 	SCIx_PROBE_REGTYPE,
 
@@ -123,6 +134,7 @@
 struct plat_sci_port {
 	unsigned long	mapbase;		/* resource base */
 	unsigned int	irqs[SCIx_NR_IRQS];	/* ERI, RXI, TXI, BRI */
+	unsigned int	gpios[SCIx_NR_FNS];	/* SCK, RXD, TXD, CTS, RTS */
 	unsigned int	type;			/* SCI / SCIF / IRDA */
 	upf_t		flags;			/* UPF_* flags */
 	unsigned long	capabilities;		/* Port features/capabilities */