[PATCH/RFC] ARM: shmobile: rcar-gen2: Add support for RZ/G CPG/MSSR bindings

[Geert Uytterhoeven <geert+renesas@glider.be>]

When using the new CPG/MSSR bindings, there's no longer a
"renesas,rcar-gen2-cpg-clocks" node.  Add support for finding the
external clock crystal oscillator on RZ/G1M and RZ/G1E through a
"renesas,r8a774x-cpg-mssr" node.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
	Hi Sergei,

As I had this patch more or less ready (using r8a779[0-5] instead of
r8a774[35] though), and you're gonna need it as a prerequisite for the
r8a7743 CPG/MSSR driver, I'm sending it now.

 arch/arm/mach-shmobile/setup-rcar-gen2.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-shmobile/setup-rcar-gen2.c b/arch/arm/mach-shmobile/setup-rcar-gen2.c
index b527258e0a62e806..e216f3f83d26ecbb 100644
--- a/arch/arm/mach-shmobile/setup-rcar-gen2.c
+++ b/arch/arm/mach-shmobile/setup-rcar-gen2.c
@@ -46,17 +46,27 @@ u32 rcar_gen2_read_mode_pins(void)
 	return mode;
 }
 
+static const struct of_device_id cpg_matches[] __initconst = {
+	{ .compatible = "renesas,rcar-gen2-cpg-clocks", },
+	{ .compatible = "renesas,r8a7743-cpg-mssr", .data = "extal" },
+	{ .compatible = "renesas,r8a7745-cpg-mssr", .data = "extal" },
+	{ /* sentinel */ }
+};
+
 static unsigned int __init get_extal_freq(void)
 {
+	const struct of_device_id *match;
 	struct device_node *cpg, *extal;
 	u32 freq = 20000000;
+	int idx = 0;
 
-	cpg = of_find_compatible_node(NULL, NULL,
-				      "renesas,rcar-gen2-cpg-clocks");
+	cpg = of_find_matching_node_and_match(NULL, cpg_matches, &match);
 	if (!cpg)
 		return freq;
 
-	extal = of_parse_phandle(cpg, "clocks", 0);
+	if (match->data)
+		idx = of_property_match_string(cpg, "clock-names", match->data);
+	extal = of_parse_phandle(cpg, "clocks", idx);
 	of_node_put(cpg);
 	if (!extal)
 		return freq;
-- 
1.9.1