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/module.h>
10 #include <linux/slab.h>
11 
12 #include "clk-mtk.h"
13 #include "clk-cpumux.h"
14 
15 static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct clk_hw *_hw)
16 {
17 	return container_of(_hw, struct mtk_clk_cpumux, hw);
18 }
19 
20 static u8 clk_cpumux_get_parent(struct clk_hw *hw)
21 {
22 	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
23 	unsigned int val;
24 
25 	regmap_read(mux->regmap, mux->reg, &val);
26 
27 	val >>= mux->shift;
28 	val &= mux->mask;
29 
30 	return val;
31 }
32 
33 static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
34 {
35 	struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
36 	u32 mask, val;
37 
38 	val = index << mux->shift;
39 	mask = mux->mask << mux->shift;
40 
41 	return regmap_update_bits(mux->regmap, mux->reg, mask, val);
42 }
43 
44 static const struct clk_ops clk_cpumux_ops = {
45 	.get_parent = clk_cpumux_get_parent,
46 	.set_parent = clk_cpumux_set_parent,
47 };
48 
49 static struct clk *
50 mtk_clk_register_cpumux(const struct mtk_composite *mux,
51 			struct regmap *regmap)
52 {
53 	struct mtk_clk_cpumux *cpumux;
54 	struct clk *clk;
55 	struct clk_init_data init;
56 
57 	cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
58 	if (!cpumux)
59 		return ERR_PTR(-ENOMEM);
60 
61 	init.name = mux->name;
62 	init.ops = &clk_cpumux_ops;
63 	init.parent_names = mux->parent_names;
64 	init.num_parents = mux->num_parents;
65 	init.flags = mux->flags;
66 
67 	cpumux->reg = mux->mux_reg;
68 	cpumux->shift = mux->mux_shift;
69 	cpumux->mask = BIT(mux->mux_width) - 1;
70 	cpumux->regmap = regmap;
71 	cpumux->hw.init = &init;
72 
73 	clk = clk_register(NULL, &cpumux->hw);
74 	if (IS_ERR(clk))
75 		kfree(cpumux);
76 
77 	return clk;
78 }
79 
80 int mtk_clk_register_cpumuxes(struct device_node *node,
81 			      const struct mtk_composite *clks, int num,
82 			      struct clk_onecell_data *clk_data)
83 {
84 	int i;
85 	struct clk *clk;
86 	struct regmap *regmap;
87 
88 	regmap = device_node_to_regmap(node);
89 	if (IS_ERR(regmap)) {
90 		pr_err("Cannot find regmap for %pOF: %ld\n", node,
91 		       PTR_ERR(regmap));
92 		return PTR_ERR(regmap);
93 	}
94 
95 	for (i = 0; i < num; i++) {
96 		const struct mtk_composite *mux = &clks[i];
97 
98 		clk = mtk_clk_register_cpumux(mux, regmap);
99 		if (IS_ERR(clk)) {
100 			pr_err("Failed to register clk %s: %ld\n",
101 			       mux->name, PTR_ERR(clk));
102 			continue;
103 		}
104 
105 		clk_data->clks[mux->id] = clk;
106 	}
107 
108 	return 0;
109 }
110 
111 MODULE_LICENSE("GPL");
112