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: NNicolin Chen <Guangyu.Chen@freescale.com>
Signed-off-by: NShawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/clk-imx6q.c

@@ -475,6 +475,9 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
 	if (ret)
 		pr_warn("failed to set up CLKO: %d\n", ret);
 
+	/* Audio-related clocks configuration */
+	clk_set_parent(clk[spdif_sel], clk[pll3_pfd3_454m]);
+
 	/* All existing boards with PCIe use LVDS1 */
 	if (IS_ENABLED(CONFIG_PCI_IMX6))
 		clk_set_parent(clk[lvds1_sel], clk[sata_ref]);

arch/arm/mach-imx/clk-imx6sl.c

@@ -261,6 +261,9 @@ static void __init imx6sl_clocks_init(struct device_node *ccm_node)
 		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);