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
13static 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(map: common->regmap, reg: common->reg, val: &reg);
22
23 if (set)
24 reg |= sg->enable_mask;
25 else
26 reg &= ~sg->enable_mask;
27
28 regmap_write(map: common->regmap, reg: common->reg, val: reg);
29}
30
31static 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(map: common->regmap, reg: common->reg + offset,
48 val: sg->enable_mask);
49}
50
51static 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, en: false);
56}
57
58static 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, en: true);
63
64 return 0;
65}
66
67static 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, en: false);
72}
73
74static 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, en: true);
79
80 return 0;
81}
82
83static 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, en: true);
88 udelay(sg->udelay);
89
90 return 0;
91}
92
93static 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(hw: parent))
103 return 0;
104 }
105
106 regmap_read(map: common->regmap, reg: common->reg, val: &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
116const struct clk_ops sprd_gate_ops = {
117 .disable = sprd_gate_disable,
118 .enable = sprd_gate_enable,
119 .is_enabled = sprd_gate_is_enabled,
120};
121EXPORT_SYMBOL_GPL(sprd_gate_ops);
122
123const 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};
128EXPORT_SYMBOL_GPL(sprd_sc_gate_ops);
129
130const 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};
135EXPORT_SYMBOL_GPL(sprd_pll_sc_gate_ops);
136

source code of linux/drivers/clk/sprd/gate.c