clk: mediatek: Add initial common clock support for Mediatek SoCs.

This patch adds common clock support for Mediatek SoCs, including plls,
muxes and clock gates.

Signed-off-by: James Liao <jamesjj.liao@mediatek.com>
Signed-off-by: Henry Chen <henryc.chen@mediatek.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
[sboyd@codeaurora.org: Squelch checkpatch warning in clk-mtk.h]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

1 files changed, 220 insertions, 0 deletions

diff --git a/drivers/clk/mediatek/clk-mtk.c b/drivers/clk/mediatek/clk-mtk.c
new file mode 100644
index 000000000000..18444aea63c9
--- /dev/null
+++ b/drivers/clk/mediatek/clk-mtk.c
@@ -0,0 +1,220 @@
+/*
+ * Copyright (c) 2014 MediaTek Inc.
+ * Author: James Liao <jamesjj.liao@mediatek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/clkdev.h>
+#include <linux/mfd/syscon.h>
+
+#include "clk-mtk.h"
+#include "clk-gate.h"
+
+struct clk_onecell_data *mtk_alloc_clk_data(unsigned int clk_num)
+{
+	int i;
+	struct clk_onecell_data *clk_data;
+
+	clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
+	if (!clk_data)
+		return NULL;
+
+	clk_data->clks = kcalloc(clk_num, sizeof(*clk_data->clks), GFP_KERNEL);
+	if (!clk_data->clks)
+		goto err_out;
+
+	clk_data->clk_num = clk_num;
+
+	for (i = 0; i < clk_num; i++)
+		clk_data->clks[i] = ERR_PTR(-ENOENT);
+
+	return clk_data;
+err_out:
+	kfree(clk_data);
+
+	return NULL;
+}
+
+void mtk_clk_register_factors(const struct mtk_fixed_factor *clks, int num,
+		struct clk_onecell_data *clk_data)
+{
+	int i;
+	struct clk *clk;
+
+	for (i = 0; i < num; i++) {
+		const struct mtk_fixed_factor *ff = &clks[i];
+
+		clk = clk_register_fixed_factor(NULL, ff->name, ff->parent_name,
+				CLK_SET_RATE_PARENT, ff->mult, ff->div);
+
+		if (IS_ERR(clk)) {
+			pr_err("Failed to register clk %s: %ld\n",
+					ff->name, PTR_ERR(clk));
+			continue;
+		}
+
+		if (clk_data)
+			clk_data->clks[ff->id] = clk;
+	}
+}
+
+int mtk_clk_register_gates(struct device_node *node, const struct mtk_gate *clks,
+		int num, struct clk_onecell_data *clk_data)
+{
+	int i;
+	struct clk *clk;
+	struct regmap *regmap;
+
+	if (!clk_data)
+		return -ENOMEM;
+
+	regmap = syscon_node_to_regmap(node);
+	if (IS_ERR(regmap)) {
+		pr_err("Cannot find regmap for %s: %ld\n", node->full_name,
+				PTR_ERR(regmap));
+		return PTR_ERR(regmap);
+	}
+
+	for (i = 0; i < num; i++) {
+		const struct mtk_gate *gate = &clks[i];
+
+		clk = mtk_clk_register_gate(gate->name, gate->parent_name,
+				regmap,
+				gate->regs->set_ofs,
+				gate->regs->clr_ofs,
+				gate->regs->sta_ofs,
+				gate->shift, gate->ops);
+
+		if (IS_ERR(clk)) {
+			pr_err("Failed to register clk %s: %ld\n",
+					gate->name, PTR_ERR(clk));
+			continue;
+		}
+
+		clk_data->clks[gate->id] = clk;
+	}
+
+	return 0;
+}
+
+struct clk *mtk_clk_register_composite(const struct mtk_composite *mc,
+		void __iomem *base, spinlock_t *lock)
+{
+	struct clk *clk;
+	struct clk_mux *mux = NULL;
+	struct clk_gate *gate = NULL;
+	struct clk_divider *div = NULL;
+	struct clk_hw *mux_hw = NULL, *gate_hw = NULL, *div_hw = NULL;
+	const struct clk_ops *mux_ops = NULL, *gate_ops = NULL, *div_ops = NULL;
+	const char * const *parent_names;
+	const char *parent;
+	int num_parents;
+	int ret;
+
+	if (mc->mux_shift >= 0) {
+		mux = kzalloc(sizeof(*mux), GFP_KERNEL);
+		if (!mux)
+			return ERR_PTR(-ENOMEM);
+
+		mux->reg = base + mc->mux_reg;
+		mux->mask = BIT(mc->mux_width) - 1;
+		mux->shift = mc->mux_shift;
+		mux->lock = lock;
+
+		mux_hw = &mux->hw;
+		mux_ops = &clk_mux_ops;
+
+		parent_names = mc->parent_names;
+		num_parents = mc->num_parents;
+	} else {
+		parent = mc->parent;
+		parent_names = &parent;
+		num_parents = 1;
+	}
+
+	if (mc->gate_shift >= 0) {
+		gate = kzalloc(sizeof(*gate), GFP_KERNEL);
+		if (!gate) {
+			ret = -ENOMEM;
+			goto err_out;
+		}
+
+		gate->reg = base + mc->gate_reg;
+		gate->bit_idx = mc->gate_shift;
+		gate->flags = CLK_GATE_SET_TO_DISABLE;
+		gate->lock = lock;
+
+		gate_hw = &gate->hw;
+		gate_ops = &clk_gate_ops;
+	}
+
+	if (mc->divider_shift >= 0) {
+		div = kzalloc(sizeof(*div), GFP_KERNEL);
+		if (!div) {
+			ret = -ENOMEM;
+			goto err_out;
+		}
+
+		div->reg = base + mc->divider_reg;
+		div->shift = mc->divider_shift;
+		div->width = mc->divider_width;
+		div->lock = lock;
+
+		div_hw = &div->hw;
+		div_ops = &clk_divider_ops;
+	}
+
+	clk = clk_register_composite(NULL, mc->name, parent_names, num_parents,
+		mux_hw, mux_ops,
+		div_hw, div_ops,
+		gate_hw, gate_ops,
+		mc->flags);
+
+	if (IS_ERR(clk)) {
+		kfree(gate);
+		kfree(mux);
+	}
+
+	return clk;
+err_out:
+	kfree(mux);
+
+	return ERR_PTR(ret);
+}
+
+void mtk_clk_register_composites(const struct mtk_composite *mcs,
+		int num, void __iomem *base, spinlock_t *lock,
+		struct clk_onecell_data *clk_data)
+{
+	struct clk *clk;
+	int i;
+
+	for (i = 0; i < num; i++) {
+		const struct mtk_composite *mc = &mcs[i];
+
+		clk = mtk_clk_register_composite(mc, base, lock);
+
+		if (IS_ERR(clk)) {
+			pr_err("Failed to register clk %s: %ld\n",
+					mc->name, PTR_ERR(clk));
+			continue;
+		}
+
+		if (clk_data)
+			clk_data->clks[mc->id] = clk;
+	}
+}