clk: imx: add imx_obtain_fixed_of_clock()

Add imx_obtain_fixed_of_clock() to optionally add clock not configured in
the devicetree.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Link: https://lore.kernel.org/r/20230131084642.709385-15-o.rempel@pengutronix.de

drivers/clk/imx/clk.c

@@ -110,6 +110,20 @@ struct clk_hw *imx_obtain_fixed_clock_hw(
 	return __clk_get_hw(clk);
 }
 
+struct clk_hw *imx_obtain_fixed_of_clock(struct device_node *np,
+					 const char *name, unsigned long rate)
+{
+	struct clk *clk = of_clk_get_by_name(np, name);
+	struct clk_hw *hw;
+
+	if (IS_ERR(clk))
+		hw = imx_obtain_fixed_clock_hw(name, rate);
+	else
+		hw = __clk_get_hw(clk);
+
+	return hw;
+}
+
 struct clk_hw *imx_get_clk_hw_by_name(struct device_node *np, const char *name)
 {
 	struct clk *clk;

drivers/clk/imx/clk.h

@@ -288,6 +288,9 @@ struct clk * imx_obtain_fixed_clock(
 struct clk_hw *imx_obtain_fixed_clock_hw(
 			const char *name, unsigned long rate);
 
+struct clk_hw *imx_obtain_fixed_of_clock(struct device_node *np,
+					 const char *name, unsigned long rate);
+
 struct clk_hw *imx_get_clk_hw_by_name(struct device_node *np, const char *name);
 
 struct clk_hw *imx_clk_hw_gate_exclusive(const char *name, const char *parent,