1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2015 Linaro Ltd.
4  * Author: Pi-Cheng Chen <pi-cheng.chen@linaro.org>
5  */
6 
7 #include <linux/clk-provider.h>
8 #include <linux/mfd/syscon.h>
9 #include <linux/slab.h>
10 
11 #include "clk-mtk.h"
12 #include "clk-cpumux.h"
13 
14 static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct clk_hw *_hw)
15 {
16 	return container_of(_hw, struct mtk_clk_cpumux, hw);
17 }
18 
19 static u8 clk_cpumux_get_parent(struct clk_hw *hw)
20 {
21 	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
22 	unsigned int val;
23 
24 	regmap_read(mux->regmap, mux->reg, &val);
25 
26 	val >>= mux->shift;
27 	val &= mux->mask;
28 
29 	return val;
30 }
31 
32 static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
33 {
34 	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
35 	u32 mask, val;
36 
37 	val = index << mux->shift;
38 	mask = mux->mask << mux->shift;
39 
40 	return regmap_update_bits(mux->regmap, mux->reg, mask, val);
41 }
42 
43 static const struct clk_ops clk_cpumux_ops = {
44 	.get_parent = clk_cpumux_get_parent,
45 	.set_parent = clk_cpumux_set_parent,
46 };
47 
48 static struct clk *
49 mtk_clk_register_cpumux(const struct mtk_composite *mux,
50 			struct regmap *regmap)
51 {
52 	struct mtk_clk_cpumux *cpumux;
53 	struct clk *clk;
54 	struct clk_init_data init;
55 
56 	cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
57 	if (!cpumux)
58 		return ERR_PTR(-ENOMEM);
59 
60 	init.name = mux->name;
61 	init.ops = &clk_cpumux_ops;
62 	init.parent_names = mux->parent_names;
63 	init.num_parents = mux->num_parents;
64 	init.flags = mux->flags;
65 
66 	cpumux->reg = mux->mux_reg;
67 	cpumux->shift = mux->mux_shift;
68 	cpumux->mask = BIT(mux->mux_width) - 1;
69 	cpumux->regmap = regmap;
70 	cpumux->hw.init = &init;
71 
72 	clk = clk_register(NULL, &cpumux->hw);
73 	if (IS_ERR(clk))
74 		kfree(cpumux);
75 
76 	return clk;
77 }
78 
79 int mtk_clk_register_cpumuxes(struct device_node *node,
80 			      const struct mtk_composite *clks, int num,
81 			      struct clk_onecell_data *clk_data)
82 {
83 	int i;
84 	struct clk *clk;
85 	struct regmap *regmap;
86 
87 	regmap = device_node_to_regmap(node);
88 	if (IS_ERR(regmap)) {
89 		pr_err("Cannot find regmap for %pOF: %ld\n", node,
90 		       PTR_ERR(regmap));
91 		return PTR_ERR(regmap);
92 	}
93 
94 	for (i = 0; i < num; i++) {
95 		const struct mtk_composite *mux = &clks[i];
96 
97 		clk = mtk_clk_register_cpumux(mux, regmap);
98 		if (IS_ERR(clk)) {
99 			pr_err("Failed to register clk %s: %ld\n",
100 			       mux->name, PTR_ERR(clk));
101 			continue;
102 		}
103 
104 		clk_data->clks[mux->id] = clk;
105 	}
106 
107 	return 0;
108 }
109