serial: sh-sci: Add device tree support for r8a7779

According to the platform data for the legacy-C initialisation of sh-sci
for the r8a7779 SoC and my own testing the SCIx_SH4_SCIF_REGTYPE bit of
scscr needs to be set.
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/serial/renesas,sci-serial.txt

@@ -12,6 +12,7 @@ Required properties:
     - "renesas,scifa-r8a7791" for R8A7791 (R-Car M2) SCIFA compatible UART.
     - "renesas,scifb-r8a7791" for R8A7791 (R-Car M2) SCIFB compatible UART.
     - "renesas,hscif-r8a7791" for R8A7791 (R-Car M2) HSCIF compatible UART.
+    - "renesas,scif-r8a7779" for R8A7779 (R-Car H1) SCIF compatible UART.
     - "renesas,scif" for generic SCIF compatible UART.
     - "renesas,scifa" for generic SCIFA compatible UART.
     - "renesas,scifb" for generic SCIFB compatible UART.

drivers/tty/serial/sh-sci.c

@@ -2419,6 +2419,7 @@ static int sci_remove(struct platform_device *dev)
 struct sci_port_info {
 	unsigned int type;
 	unsigned int regtype;
+	unsigned int scscr_extra;
 };
 
 static const struct of_device_id of_sci_match[] = {
@@ -2428,6 +2429,13 @@ static const struct of_device_id of_sci_match[] = {
 			.type = PORT_SCIF,
 			.regtype = SCIx_SH4_SCIF_REGTYPE,
 		},
+	}, {
+		.compatible = "renesas,scif-r8a7779",
+		.data = (void *)&(const struct sci_port_info) {
+			.type = PORT_SCIF,
+			.regtype = SCIx_SH4_SCIF_REGTYPE,
+			.scscr_extra = SCSCR_CKE1,
+		},
 	}, {
 		.compatible = "renesas,scifa",
 		.data = &(const struct sci_port_info) {
@@ -2488,7 +2496,7 @@ sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id)
 	p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
 	p->type = info->type;
 	p->regtype = info->regtype;
-	p->scscr = SCSCR_RE | SCSCR_TE;
+	p->scscr = SCSCR_RE | SCSCR_TE | info->scscr_extra;
 
 	return p;
 }