1 /*
2 * Copyright (C) 2016 Socionext Inc.
3 * Author: Masahiro Yamada <yamada.masahiro@socionext.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 #include <linux/clk-provider.h>
17 #include <linux/device.h>
18 #include <linux/regmap.h>
19
20 #include "clk-uniphier.h"
21
22 struct uniphier_clk_mux {
23 struct clk_hw hw;
24 struct regmap *regmap;
25 unsigned int reg;
26 const unsigned int *masks;
27 const unsigned int *vals;
28 };
29
30 #define to_uniphier_clk_mux(_hw) container_of(_hw, struct uniphier_clk_mux, hw)
31
uniphier_clk_mux_set_parent(struct clk_hw * hw,u8 index)32 static int uniphier_clk_mux_set_parent(struct clk_hw *hw, u8 index)
33 {
34 struct uniphier_clk_mux *mux = to_uniphier_clk_mux(hw);
35
36 return regmap_write_bits(mux->regmap, mux->reg, mux->masks[index],
37 mux->vals[index]);
38 }
39
uniphier_clk_mux_get_parent(struct clk_hw * hw)40 static u8 uniphier_clk_mux_get_parent(struct clk_hw *hw)
41 {
42 struct uniphier_clk_mux *mux = to_uniphier_clk_mux(hw);
43 unsigned int num_parents = clk_hw_get_num_parents(hw);
44 int ret;
45 unsigned int val;
46 unsigned int i;
47
48 ret = regmap_read(mux->regmap, mux->reg, &val);
49 if (ret)
50 return ret;
51
52 for (i = 0; i < num_parents; i++)
53 if ((mux->masks[i] & val) == mux->vals[i])
54 return i;
55
56 return -EINVAL;
57 }
58
59 static const struct clk_ops uniphier_clk_mux_ops = {
60 .determine_rate = __clk_mux_determine_rate,
61 .set_parent = uniphier_clk_mux_set_parent,
62 .get_parent = uniphier_clk_mux_get_parent,
63 };
64
uniphier_clk_register_mux(struct device * dev,struct regmap * regmap,const char * name,const struct uniphier_clk_mux_data * data)65 struct clk_hw *uniphier_clk_register_mux(struct device *dev,
66 struct regmap *regmap,
67 const char *name,
68 const struct uniphier_clk_mux_data *data)
69 {
70 struct uniphier_clk_mux *mux;
71 struct clk_init_data init;
72 int ret;
73
74 mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
75 if (!mux)
76 return ERR_PTR(-ENOMEM);
77
78 init.name = name;
79 init.ops = &uniphier_clk_mux_ops;
80 init.flags = CLK_SET_RATE_PARENT;
81 init.parent_names = data->parent_names;
82 init.num_parents = data->num_parents,
83
84 mux->regmap = regmap;
85 mux->reg = data->reg;
86 mux->masks = data->masks;
87 mux->vals = data->vals;
88 mux->hw.init = &init;
89
90 ret = devm_clk_hw_register(dev, &mux->hw);
91 if (ret)
92 return ERR_PTR(ret);
93
94 return &mux->hw;
95 }
96