1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Spreadtrum multiplexer clock driver
4 //
5 // Copyright (C) 2017 Spreadtrum, Inc.
6 // Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
7
8 #include <linux/clk.h>
9 #include <linux/clk-provider.h>
10 #include <linux/regmap.h>
11
12 #include "mux.h"
13
sprd_mux_helper_get_parent(const struct sprd_clk_common * common,const struct sprd_mux_ssel * mux)14 u8 sprd_mux_helper_get_parent(const struct sprd_clk_common *common,
15 const struct sprd_mux_ssel *mux)
16 {
17 unsigned int reg;
18 u8 parent;
19 int num_parents;
20 int i;
21
22 regmap_read(common->regmap, common->reg, ®);
23 parent = reg >> mux->shift;
24 parent &= (1 << mux->width) - 1;
25
26 if (!mux->table)
27 return parent;
28
29 num_parents = clk_hw_get_num_parents(&common->hw);
30
31 for (i = 0; i < num_parents - 1; i++)
32 if (parent >= mux->table[i] && parent < mux->table[i + 1])
33 return i;
34
35 return num_parents - 1;
36 }
37 EXPORT_SYMBOL_GPL(sprd_mux_helper_get_parent);
38
sprd_mux_get_parent(struct clk_hw * hw)39 static u8 sprd_mux_get_parent(struct clk_hw *hw)
40 {
41 struct sprd_mux *cm = hw_to_sprd_mux(hw);
42
43 return sprd_mux_helper_get_parent(&cm->common, &cm->mux);
44 }
45
sprd_mux_helper_set_parent(const struct sprd_clk_common * common,const struct sprd_mux_ssel * mux,u8 index)46 int sprd_mux_helper_set_parent(const struct sprd_clk_common *common,
47 const struct sprd_mux_ssel *mux,
48 u8 index)
49 {
50 unsigned int reg;
51
52 if (mux->table)
53 index = mux->table[index];
54
55 regmap_read(common->regmap, common->reg, ®);
56 reg &= ~GENMASK(mux->width + mux->shift - 1, mux->shift);
57 regmap_write(common->regmap, common->reg,
58 reg | (index << mux->shift));
59
60 return 0;
61 }
62 EXPORT_SYMBOL_GPL(sprd_mux_helper_set_parent);
63
sprd_mux_set_parent(struct clk_hw * hw,u8 index)64 static int sprd_mux_set_parent(struct clk_hw *hw, u8 index)
65 {
66 struct sprd_mux *cm = hw_to_sprd_mux(hw);
67
68 return sprd_mux_helper_set_parent(&cm->common, &cm->mux, index);
69 }
70
71 const struct clk_ops sprd_mux_ops = {
72 .get_parent = sprd_mux_get_parent,
73 .set_parent = sprd_mux_set_parent,
74 .determine_rate = __clk_mux_determine_rate,
75 };
76 EXPORT_SYMBOL_GPL(sprd_mux_ops);
77