ARM: imx6: Derive spdif clock from pll3_pfd3_454m

SPDIF can derive a TX clock for playback from one of its clock sources --
spdif root clock to match its supporting sample rates. So this patch set
the spdif root clock's parent to pll3_pfd3_454m since the pll3_pfd3_454m
can approximately meet its sample rate requirement.

Signed-off-by: Nicolin Chen <Guangyu.Chen@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
diff --git a/arch/arm/mach-imx/clk-imx6sl.c b/arch/arm/mach-imx/clk-imx6sl.c
index a747a7d..a222280 100644
--- a/arch/arm/mach-imx/clk-imx6sl.c
+++ b/arch/arm/mach-imx/clk-imx6sl.c
@@ -261,6 +261,9 @@
 		clk_prepare_enable(clks[IMX6SL_CLK_USBPHY2_GATE]);
 	}
 
+	/* Audio-related clocks configuration */
+	clk_set_parent(clks[IMX6SL_CLK_SPDIF0_SEL], clks[IMX6SL_CLK_PLL3_PFD3]);
+
 	np = of_find_compatible_node(NULL, NULL, "fsl,imx6sl-gpt");
 	base = of_iomap(np, 0);
 	WARN_ON(!base);