1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Spreadtrum gate clock driver
4 //
5 // Copyright (C) 2017 Spreadtrum, Inc.
6 // Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
7
8 #include <linux/clk-provider.h>
9 #include <linux/regmap.h>
10
11 #include "gate.h"
12
clk_gate_toggle(const struct sprd_gate * sg,bool en)13 static void clk_gate_toggle(const struct sprd_gate *sg, bool en)
14 {
15 const struct sprd_clk_common *common = &sg->common;
16 unsigned int reg;
17 bool set = sg->flags & CLK_GATE_SET_TO_DISABLE ? true : false;
18
19 set ^= en;
20
21 regmap_read(common->regmap, common->reg, ®);
22
23 if (set)
24 reg |= sg->enable_mask;
25 else
26 reg &= ~sg->enable_mask;
27
28 regmap_write(common->regmap, common->reg, reg);
29 }
30
clk_sc_gate_toggle(const struct sprd_gate * sg,bool en)31 static void clk_sc_gate_toggle(const struct sprd_gate *sg, bool en)
32 {
33 const struct sprd_clk_common *common = &sg->common;
34 bool set = sg->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
35 unsigned int offset;
36
37 set ^= en;
38
39 /*
40 * Each set/clear gate clock has three registers:
41 * common->reg - base register
42 * common->reg + offset - set register
43 * common->reg + 2 * offset - clear register
44 */
45 offset = set ? sg->sc_offset : sg->sc_offset * 2;
46
47 regmap_write(common->regmap, common->reg + offset,
48 sg->enable_mask);
49 }
50
sprd_gate_disable(struct clk_hw * hw)51 static void sprd_gate_disable(struct clk_hw *hw)
52 {
53 struct sprd_gate *sg = hw_to_sprd_gate(hw);
54
55 clk_gate_toggle(sg, false);
56 }
57
sprd_gate_enable(struct clk_hw * hw)58 static int sprd_gate_enable(struct clk_hw *hw)
59 {
60 struct sprd_gate *sg = hw_to_sprd_gate(hw);
61
62 clk_gate_toggle(sg, true);
63
64 return 0;
65 }
66
sprd_sc_gate_disable(struct clk_hw * hw)67 static void sprd_sc_gate_disable(struct clk_hw *hw)
68 {
69 struct sprd_gate *sg = hw_to_sprd_gate(hw);
70
71 clk_sc_gate_toggle(sg, false);
72 }
73
sprd_sc_gate_enable(struct clk_hw * hw)74 static int sprd_sc_gate_enable(struct clk_hw *hw)
75 {
76 struct sprd_gate *sg = hw_to_sprd_gate(hw);
77
78 clk_sc_gate_toggle(sg, true);
79
80 return 0;
81 }
82
sprd_pll_sc_gate_prepare(struct clk_hw * hw)83 static int sprd_pll_sc_gate_prepare(struct clk_hw *hw)
84 {
85 struct sprd_gate *sg = hw_to_sprd_gate(hw);
86
87 clk_sc_gate_toggle(sg, true);
88 udelay(sg->udelay);
89
90 return 0;
91 }
92
sprd_gate_is_enabled(struct clk_hw * hw)93 static int sprd_gate_is_enabled(struct clk_hw *hw)
94 {
95 struct sprd_gate *sg = hw_to_sprd_gate(hw);
96 struct sprd_clk_common *common = &sg->common;
97 struct clk_hw *parent;
98 unsigned int reg;
99
100 if (sg->flags & SPRD_GATE_NON_AON) {
101 parent = clk_hw_get_parent(hw);
102 if (!parent || !clk_hw_is_enabled(parent))
103 return 0;
104 }
105
106 regmap_read(common->regmap, common->reg, ®);
107
108 if (sg->flags & CLK_GATE_SET_TO_DISABLE)
109 reg ^= sg->enable_mask;
110
111 reg &= sg->enable_mask;
112
113 return reg ? 1 : 0;
114 }
115
116 const struct clk_ops sprd_gate_ops = {
117 .disable = sprd_gate_disable,
118 .enable = sprd_gate_enable,
119 .is_enabled = sprd_gate_is_enabled,
120 };
121 EXPORT_SYMBOL_GPL(sprd_gate_ops);
122
123 const struct clk_ops sprd_sc_gate_ops = {
124 .disable = sprd_sc_gate_disable,
125 .enable = sprd_sc_gate_enable,
126 .is_enabled = sprd_gate_is_enabled,
127 };
128 EXPORT_SYMBOL_GPL(sprd_sc_gate_ops);
129
130 const struct clk_ops sprd_pll_sc_gate_ops = {
131 .unprepare = sprd_sc_gate_disable,
132 .prepare = sprd_pll_sc_gate_prepare,
133 .is_enabled = sprd_gate_is_enabled,
134 };
135 EXPORT_SYMBOL_GPL(sprd_pll_sc_gate_ops);
136