clk: meson: introduce meson-clkc-utils

Let's introduce a new module called meson-clkc-utils that
will contain shared utility functions for all Amlogic clock
controller drivers.

The first utility function is a replacement of of_clk_hw_onecell_get
in order to get rid of the NR_CLKS define in all Amlogic clock
drivers.

The goal is to move all duplicate probe and init code in this module.

[jbrunet: Fixed MODULE_LICENCE checkpatch warning]
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20230607-topic-amlogic-upstream-clkid-public-migration-v2-1-38172d17c27a@linaro.org
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>

drivers/clk/meson/Kconfig

@@ -30,6 +30,9 @@ config COMMON_CLK_MESON_VID_PLL_DIV
 	tristate
 	select COMMON_CLK_MESON_REGMAP
 
+config COMMON_CLK_MESON_CLKC_UTILS
+	tristate
+
 config COMMON_CLK_MESON_AO_CLKC
 	tristate
 	select COMMON_CLK_MESON_REGMAP

drivers/clk/meson/Makefile

@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 # Amlogic clock drivers
 
+obj-$(CONFIG_COMMON_CLK_MESON_CLKC_UTILS) += meson-clkc-utils.o
 obj-$(CONFIG_COMMON_CLK_MESON_AO_CLKC) += meson-aoclk.o
 obj-$(CONFIG_COMMON_CLK_MESON_CPU_DYNDIV) += clk-cpu-dyndiv.o
 obj-$(CONFIG_COMMON_CLK_MESON_DUALDIV) += clk-dualdiv.o

drivers/clk/meson/meson-clkc-utils.c

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2023 Neil Armstrong <neil.armstrong@linaro.org>
+ */
+
+#include <linux/of_device.h>
+#include <linux/clk-provider.h>
+#include <linux/module.h>
+#include "meson-clkc-utils.h"
+
+struct clk_hw *meson_clk_hw_get(struct of_phandle_args *clkspec, void *clk_hw_data)
+{
+	const struct meson_clk_hw_data *data = clk_hw_data;
+	unsigned int idx = clkspec->args[0];
+
+	if (idx >= data->num) {
+		pr_err("%s: invalid index %u\n", __func__, idx);
+		return ERR_PTR(-EINVAL);
+	}
+
+	return data->hws[idx];
+}
+EXPORT_SYMBOL_GPL(meson_clk_hw_get);
+
+MODULE_LICENSE("GPL");

drivers/clk/meson/meson-clkc-utils.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: (GPL-2.0+ OR MIT) */
+/*
+ * Copyright (c) 2023 Neil Armstrong <neil.armstrong@linaro.org>
+ */
+
+#ifndef __MESON_CLKC_UTILS_H__
+#define __MESON_CLKC_UTILS_H__
+
+#include <linux/of_device.h>
+#include <linux/clk-provider.h>
+
+struct meson_clk_hw_data {
+	struct clk_hw	**hws;
+	unsigned int	num;
+};
+
+struct clk_hw *meson_clk_hw_get(struct of_phandle_args *clkspec, void *clk_hw_data);
+
+#endif