clk: at91: rework main clk implementation

AT91 main clk is a clk multiplexer and not a simple fixed rate clk as
currently implemented.

In some SoCs (sam9x5, sama5, sam9g45 families) this multiplexer can
choose among 2 sources: an internal RC oscillator circuit and an
oscillator using an external crystal.

In other Socs (sam9260, rm9200 families) the multiplexer source is
hardcoded to the external crystal oscillator.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 4413509..42cc7cc 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -58,8 +58,14 @@
 int of_at91_get_clk_range(struct device_node *np, const char *propname,
 			  struct clk_range *range);
 
+extern void __init of_at91rm9200_clk_main_osc_setup(struct device_node *np,
+						    struct at91_pmc *pmc);
+extern void __init of_at91sam9x5_clk_main_rc_osc_setup(struct device_node *np,
+						       struct at91_pmc *pmc);
 extern void __init of_at91rm9200_clk_main_setup(struct device_node *np,
 						struct at91_pmc *pmc);
+extern void __init of_at91sam9x5_clk_main_setup(struct device_node *np,
+						struct at91_pmc *pmc);
 
 extern void __init of_at91rm9200_clk_pll_setup(struct device_node *np,
 					       struct at91_pmc *pmc);