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/container_of.h>
9 #include <linux/err.h>
10 #include <linux/mfd/syscon.h>
11 #include <linux/module.h>
12 #include <linux/regmap.h>
13 #include <linux/slab.h>
14
15 #include "clk-mtk.h"
16 #include "clk-cpumux.h"
17
18 struct mtk_clk_cpumux {
19 struct clk_hw hw;
20 struct regmap *regmap;
21 u32 reg;
22 u32 mask;
23 u8 shift;
24 };
25
to_mtk_clk_cpumux(struct clk_hw * _hw)26 static inline struct mtk_clk_cpumux *to_mtk_clk_cpumux(struct clk_hw *_hw)
27 {
28 return container_of(_hw, struct mtk_clk_cpumux, hw);
29 }
30
clk_cpumux_get_parent(struct clk_hw * hw)31 static u8 clk_cpumux_get_parent(struct clk_hw *hw)
32 {
33 struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
34 unsigned int val;
35
36 regmap_read(mux->regmap, mux->reg, &val);
37
38 val >>= mux->shift;
39 val &= mux->mask;
40
41 return val;
42 }
43
clk_cpumux_set_parent(struct clk_hw * hw,u8 index)44 static int clk_cpumux_set_parent(struct clk_hw *hw, u8 index)
45 {
46 struct mtk_clk_cpumux *mux = to_mtk_clk_cpumux(hw);
47 u32 mask, val;
48
49 val = index << mux->shift;
50 mask = mux->mask << mux->shift;
51
52 return regmap_update_bits(mux->regmap, mux->reg, mask, val);
53 }
54
55 static const struct clk_ops clk_cpumux_ops = {
56 .get_parent = clk_cpumux_get_parent,
57 .set_parent = clk_cpumux_set_parent,
58 };
59
60 static struct clk_hw *
mtk_clk_register_cpumux(const struct mtk_composite * mux,struct regmap * regmap)61 mtk_clk_register_cpumux(const struct mtk_composite *mux,
62 struct regmap *regmap)
63 {
64 struct mtk_clk_cpumux *cpumux;
65 int ret;
66 struct clk_init_data init;
67
68 cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
69 if (!cpumux)
70 return ERR_PTR(-ENOMEM);
71
72 init.name = mux->name;
73 init.ops = &clk_cpumux_ops;
74 init.parent_names = mux->parent_names;
75 init.num_parents = mux->num_parents;
76 init.flags = mux->flags;
77
78 cpumux->reg = mux->mux_reg;
79 cpumux->shift = mux->mux_shift;
80 cpumux->mask = BIT(mux->mux_width) - 1;
81 cpumux->regmap = regmap;
82 cpumux->hw.init = &init;
83
84 ret = clk_hw_register(NULL, &cpumux->hw);
85 if (ret) {
86 kfree(cpumux);
87 return ERR_PTR(ret);
88 }
89
90 return &cpumux->hw;
91 }
92
mtk_clk_unregister_cpumux(struct clk_hw * hw)93 static void mtk_clk_unregister_cpumux(struct clk_hw *hw)
94 {
95 struct mtk_clk_cpumux *cpumux;
96 if (!hw)
97 return;
98
99 cpumux = to_mtk_clk_cpumux(hw);
100
101 clk_hw_unregister(hw);
102 kfree(cpumux);
103 }
104
mtk_clk_register_cpumuxes(struct device_node * node,const struct mtk_composite * clks,int num,struct clk_hw_onecell_data * clk_data)105 int mtk_clk_register_cpumuxes(struct device_node *node,
106 const struct mtk_composite *clks, int num,
107 struct clk_hw_onecell_data *clk_data)
108 {
109 int i;
110 struct clk_hw *hw;
111 struct regmap *regmap;
112
113 regmap = device_node_to_regmap(node);
114 if (IS_ERR(regmap)) {
115 pr_err("Cannot find regmap for %pOF: %pe\n", node, regmap);
116 return PTR_ERR(regmap);
117 }
118
119 for (i = 0; i < num; i++) {
120 const struct mtk_composite *mux = &clks[i];
121
122 if (!IS_ERR_OR_NULL(clk_data->hws[mux->id])) {
123 pr_warn("%pOF: Trying to register duplicate clock ID: %d\n",
124 node, mux->id);
125 continue;
126 }
127
128 hw = mtk_clk_register_cpumux(mux, regmap);
129 if (IS_ERR(hw)) {
130 pr_err("Failed to register clk %s: %pe\n", mux->name,
131 hw);
132 goto err;
133 }
134
135 clk_data->hws[mux->id] = hw;
136 }
137
138 return 0;
139
140 err:
141 while (--i >= 0) {
142 const struct mtk_composite *mux = &clks[i];
143
144 if (IS_ERR_OR_NULL(clk_data->hws[mux->id]))
145 continue;
146
147 mtk_clk_unregister_cpumux(clk_data->hws[mux->id]);
148 clk_data->hws[mux->id] = ERR_PTR(-ENOENT);
149 }
150
151 return PTR_ERR(hw);
152 }
153 EXPORT_SYMBOL_GPL(mtk_clk_register_cpumuxes);
154
mtk_clk_unregister_cpumuxes(const struct mtk_composite * clks,int num,struct clk_hw_onecell_data * clk_data)155 void mtk_clk_unregister_cpumuxes(const struct mtk_composite *clks, int num,
156 struct clk_hw_onecell_data *clk_data)
157 {
158 int i;
159
160 for (i = num; i > 0; i--) {
161 const struct mtk_composite *mux = &clks[i - 1];
162
163 if (IS_ERR_OR_NULL(clk_data->hws[mux->id]))
164 continue;
165
166 mtk_clk_unregister_cpumux(clk_data->hws[mux->id]);
167 clk_data->hws[mux->id] = ERR_PTR(-ENOENT);
168 }
169 }
170 EXPORT_SYMBOL_GPL(mtk_clk_unregister_cpumuxes);
171
172 MODULE_LICENSE("GPL");
173