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 .determine_rate = clk_hw_determine_rate_no_reparent,
57 .get_parent = clk_cpumux_get_parent,
58 .set_parent = clk_cpumux_set_parent,
59 };
60
61 static struct clk_hw *
mtk_clk_register_cpumux(struct device * dev,const struct mtk_composite * mux,struct regmap * regmap)62 mtk_clk_register_cpumux(struct device *dev, const struct mtk_composite *mux,
63 struct regmap *regmap)
64 {
65 struct mtk_clk_cpumux *cpumux;
66 int ret;
67 struct clk_init_data init;
68
69 cpumux = kzalloc(sizeof(*cpumux), GFP_KERNEL);
70 if (!cpumux)
71 return ERR_PTR(-ENOMEM);
72
73 init.name = mux->name;
74 init.ops = &clk_cpumux_ops;
75 init.parent_names = mux->parent_names;
76 init.num_parents = mux->num_parents;
77 init.flags = mux->flags;
78
79 cpumux->reg = mux->mux_reg;
80 cpumux->shift = mux->mux_shift;
81 cpumux->mask = BIT(mux->mux_width) - 1;
82 cpumux->regmap = regmap;
83 cpumux->hw.init = &init;
84
85 ret = clk_hw_register(dev, &cpumux->hw);
86 if (ret) {
87 kfree(cpumux);
88 return ERR_PTR(ret);
89 }
90
91 return &cpumux->hw;
92 }
93
mtk_clk_unregister_cpumux(struct clk_hw * hw)94 static void mtk_clk_unregister_cpumux(struct clk_hw *hw)
95 {
96 struct mtk_clk_cpumux *cpumux;
97 if (!hw)
98 return;
99
100 cpumux = to_mtk_clk_cpumux(hw);
101
102 clk_hw_unregister(hw);
103 kfree(cpumux);
104 }
105
mtk_clk_register_cpumuxes(struct device * dev,struct device_node * node,const struct mtk_composite * clks,int num,struct clk_hw_onecell_data * clk_data)106 int mtk_clk_register_cpumuxes(struct device *dev, struct device_node *node,
107 const struct mtk_composite *clks, int num,
108 struct clk_hw_onecell_data *clk_data)
109 {
110 int i;
111 struct clk_hw *hw;
112 struct regmap *regmap;
113
114 regmap = device_node_to_regmap(node);
115 if (IS_ERR(regmap)) {
116 pr_err("Cannot find regmap for %pOF: %pe\n", node, regmap);
117 return PTR_ERR(regmap);
118 }
119
120 for (i = 0; i < num; i++) {
121 const struct mtk_composite *mux = &clks[i];
122
123 if (!IS_ERR_OR_NULL(clk_data->hws[mux->id])) {
124 pr_warn("%pOF: Trying to register duplicate clock ID: %d\n",
125 node, mux->id);
126 continue;
127 }
128
129 hw = mtk_clk_register_cpumux(dev, mux, regmap);
130 if (IS_ERR(hw)) {
131 pr_err("Failed to register clk %s: %pe\n", mux->name,
132 hw);
133 goto err;
134 }
135
136 clk_data->hws[mux->id] = hw;
137 }
138
139 return 0;
140
141 err:
142 while (--i >= 0) {
143 const struct mtk_composite *mux = &clks[i];
144
145 if (IS_ERR_OR_NULL(clk_data->hws[mux->id]))
146 continue;
147
148 mtk_clk_unregister_cpumux(clk_data->hws[mux->id]);
149 clk_data->hws[mux->id] = ERR_PTR(-ENOENT);
150 }
151
152 return PTR_ERR(hw);
153 }
154 EXPORT_SYMBOL_GPL(mtk_clk_register_cpumuxes);
155
mtk_clk_unregister_cpumuxes(const struct mtk_composite * clks,int num,struct clk_hw_onecell_data * clk_data)156 void mtk_clk_unregister_cpumuxes(const struct mtk_composite *clks, int num,
157 struct clk_hw_onecell_data *clk_data)
158 {
159 int i;
160
161 for (i = num; i > 0; i--) {
162 const struct mtk_composite *mux = &clks[i - 1];
163
164 if (IS_ERR_OR_NULL(clk_data->hws[mux->id]))
165 continue;
166
167 mtk_clk_unregister_cpumux(clk_data->hws[mux->id]);
168 clk_data->hws[mux->id] = ERR_PTR(-ENOENT);
169 }
170 }
171 EXPORT_SYMBOL_GPL(mtk_clk_unregister_cpumuxes);
172
173 MODULE_LICENSE("GPL");
174