[RFC PATCH 02/11] clk: imx: add clk_hw based API imx_get_clk_hw_from_dt()

[Dario Binacchi <dario.binacchi@amarulasolutions.com>]

Clock providers are recommended to use the struct clk_hw based API, so
add an IMX provider helper to get clk_hw from device tree node name.

This is a preparation patch for the upcoming support to setup clocks
directly from the device tree.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
---

 drivers/clk/imx/clk.c | 21 +++++++++++++++++++++
 drivers/clk/imx/clk.h |  3 +++
 2 files changed, 24 insertions(+)

diff --git a/drivers/clk/imx/clk.c b/drivers/clk/imx/clk.c
index b636cc099d96..6ae122ccd83e 100644
--- a/drivers/clk/imx/clk.c
+++ b/drivers/clk/imx/clk.c
@@ -68,6 +68,27 @@ void imx_check_clk_hws(struct clk_hw *clks[], unsigned int count)
 }
 EXPORT_SYMBOL_GPL(imx_check_clk_hws);
 
+struct clk_hw *imx_get_clk_hw_from_dt(struct device_node *np,
+				      const char *name)
+{
+	struct of_phandle_args clkspec;
+	struct clk *clk;
+
+	clkspec.np = of_find_node_by_name(np, name);
+	if (clkspec.np) {
+		clk = of_clk_get_from_provider(&clkspec);
+		if (!IS_ERR(clk)) {
+			pr_debug("%s: got %s clock\n", __func__, name);
+			of_node_put(clkspec.np);
+			return __clk_get_hw(clk);
+		}
+	}
+
+	pr_err("%s: failed to %s clock\n", __func__, name);
+	return ERR_PTR(-ENODEV);
+}
+EXPORT_SYMBOL_GPL(imx_get_clk_hw_from_dt);
+
 static struct clk *imx_obtain_fixed_clock_from_dt(const char *name)
 {
 	struct of_phandle_args phandle;
diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h
index 86538c990a0d..a0e6b8357eb7 100644
--- a/drivers/clk/imx/clk.h
+++ b/drivers/clk/imx/clk.h
@@ -294,6 +294,9 @@ struct clk_hw *clk_hw_register_gate2(struct device *dev, const char *name,
 		u8 clk_gate_flags, spinlock_t *lock,
 		unsigned int *share_count);
 
+struct clk_hw *imx_get_clk_hw_from_dt(struct device_node *np,
+				      const char *name);
+
 struct clk * imx_obtain_fixed_clock(
 			const char *name, unsigned long rate);
 
-- 
2.32.0