clk: Add support for I2C clocks on NXP's imx6q SoC which use CCF

This change adds support for I2C clock modeled in CCF. This code intention
is to only enable those clocks in the I2C driver with default settings.
For that reason the "busy" versions of clocks reuse the generic approach
and would need to be updated when one wants to adjust the I2C clock
frequency in U-Boot.

Signed-off-by: Lukasz Majewski <lukma@denx.de>
diff --git a/drivers/clk/imx/clk-imx6q.c b/drivers/clk/imx/clk-imx6q.c
index 92e9337..5ae4781 100644
--- a/drivers/clk/imx/clk-imx6q.c
+++ b/drivers/clk/imx/clk-imx6q.c
@@ -89,6 +89,9 @@
 };
 
 static const char *const usdhc_sels[] = { "pll2_pfd2_396m", "pll2_pfd0_352m", };
+static const char *const periph_sels[]	= { "periph_pre", "periph_clk2", };
+static const char *const periph_pre_sels[] = { "pll2_bus", "pll2_pfd2_396m",
+					       "pll2_pfd0_352m", "pll2_198m", };
 
 static int imx6q_clk_probe(struct udevice *dev)
 {
@@ -161,6 +164,24 @@
 	clk_dm(IMX6QDL_CLK_USDHC4,
 	       imx_clk_gate2("usdhc4", "usdhc4_podf", base + 0x80, 8));
 
+	clk_dm(IMX6QDL_CLK_PERIPH_PRE,
+	       imx_clk_mux("periph_pre", base + 0x18, 18, 2, periph_pre_sels,
+			   ARRAY_SIZE(periph_pre_sels)));
+	clk_dm(IMX6QDL_CLK_PERIPH,
+	       imx_clk_busy_mux("periph",  base + 0x14, 25, 1, base + 0x48,
+				5, periph_sels,  ARRAY_SIZE(periph_sels)));
+	clk_dm(IMX6QDL_CLK_AHB,
+	       imx_clk_busy_divider("ahb", "periph", base + 0x14, 10, 3,
+				    base + 0x48, 1));
+	clk_dm(IMX6QDL_CLK_IPG,
+	       imx_clk_divider("ipg", "ahb", base + 0x14, 8, 2));
+	clk_dm(IMX6QDL_CLK_IPG_PER,
+	       imx_clk_divider("ipg_per", "ipg", base + 0x1c, 0, 6));
+	clk_dm(IMX6QDL_CLK_I2C1,
+	       imx_clk_gate2("i2c1", "ipg_per", base + 0x70, 6));
+	clk_dm(IMX6QDL_CLK_I2C2,
+	       imx_clk_gate2("i2c2", "ipg_per", base + 0x70, 8));
+
 	return 0;
 }