xref: /openbmc/linux/drivers/clk/meson/clk-regmap.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018 BayLibre, SAS.
4  * Author: Jerome Brunet <jbrunet@baylibre.com>
5  */
6 
7 #include <linux/module.h>
8 #include "clk-regmap.h"
9 
10 static int clk_regmap_gate_endisable(struct clk_hw *hw, int enable)
11 {
12 	struct clk_regmap *clk = to_clk_regmap(hw);
13 	struct clk_regmap_gate_data *gate = clk_get_regmap_gate_data(clk);
14 	int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
15 
16 	set ^= enable;
17 
18 	return regmap_update_bits(clk->map, gate->offset, BIT(gate->bit_idx),
19 				  set ? BIT(gate->bit_idx) : 0);
20 }
21 
22 static int clk_regmap_gate_enable(struct clk_hw *hw)
23 {
24 	return clk_regmap_gate_endisable(hw, 1);
25 }
26 
27 static void clk_regmap_gate_disable(struct clk_hw *hw)
28 {
29 	clk_regmap_gate_endisable(hw, 0);
30 }
31 
32 static int clk_regmap_gate_is_enabled(struct clk_hw *hw)
33 {
34 	struct clk_regmap *clk = to_clk_regmap(hw);
35 	struct clk_regmap_gate_data *gate = clk_get_regmap_gate_data(clk);
36 	unsigned int val;
37 
38 	regmap_read(clk->map, gate->offset, &val);
39 	if (gate->flags & CLK_GATE_SET_TO_DISABLE)
40 		val ^= BIT(gate->bit_idx);
41 
42 	val &= BIT(gate->bit_idx);
43 
44 	return val ? 1 : 0;
45 }
46 
47 const struct clk_ops clk_regmap_gate_ops = {
48 	.enable = clk_regmap_gate_enable,
49 	.disable = clk_regmap_gate_disable,
50 	.is_enabled = clk_regmap_gate_is_enabled,
51 };
52 EXPORT_SYMBOL_GPL(clk_regmap_gate_ops);
53 
54 const struct clk_ops clk_regmap_gate_ro_ops = {
55 	.is_enabled = clk_regmap_gate_is_enabled,
56 };
57 EXPORT_SYMBOL_GPL(clk_regmap_gate_ro_ops);
58 
59 static unsigned long clk_regmap_div_recalc_rate(struct clk_hw *hw,
60 						unsigned long prate)
61 {
62 	struct clk_regmap *clk = to_clk_regmap(hw);
63 	struct clk_regmap_div_data *div = clk_get_regmap_div_data(clk);
64 	unsigned int val;
65 	int ret;
66 
67 	ret = regmap_read(clk->map, div->offset, &val);
68 	if (ret)
69 		/* Gives a hint that something is wrong */
70 		return 0;
71 
72 	val >>= div->shift;
73 	val &= clk_div_mask(div->width);
74 	return divider_recalc_rate(hw, prate, val, div->table, div->flags,
75 				   div->width);
76 }
77 
78 static int clk_regmap_div_determine_rate(struct clk_hw *hw,
79 					 struct clk_rate_request *req)
80 {
81 	struct clk_regmap *clk = to_clk_regmap(hw);
82 	struct clk_regmap_div_data *div = clk_get_regmap_div_data(clk);
83 	unsigned int val;
84 	int ret;
85 
86 	/* if read only, just return current value */
87 	if (div->flags & CLK_DIVIDER_READ_ONLY) {
88 		ret = regmap_read(clk->map, div->offset, &val);
89 		if (ret)
90 			return ret;
91 
92 		val >>= div->shift;
93 		val &= clk_div_mask(div->width);
94 
95 		return divider_ro_determine_rate(hw, req, div->table,
96 						 div->width, div->flags, val);
97 	}
98 
99 	return divider_determine_rate(hw, req, div->table, div->width,
100 				      div->flags);
101 }
102 
103 static int clk_regmap_div_set_rate(struct clk_hw *hw, unsigned long rate,
104 				   unsigned long parent_rate)
105 {
106 	struct clk_regmap *clk = to_clk_regmap(hw);
107 	struct clk_regmap_div_data *div = clk_get_regmap_div_data(clk);
108 	unsigned int val;
109 	int ret;
110 
111 	ret = divider_get_val(rate, parent_rate, div->table, div->width,
112 			      div->flags);
113 	if (ret < 0)
114 		return ret;
115 
116 	val = (unsigned int)ret << div->shift;
117 	return regmap_update_bits(clk->map, div->offset,
118 				  clk_div_mask(div->width) << div->shift, val);
119 };
120 
121 /* Would prefer clk_regmap_div_ro_ops but clashes with qcom */
122 
123 const struct clk_ops clk_regmap_divider_ops = {
124 	.recalc_rate = clk_regmap_div_recalc_rate,
125 	.determine_rate = clk_regmap_div_determine_rate,
126 	.set_rate = clk_regmap_div_set_rate,
127 };
128 EXPORT_SYMBOL_GPL(clk_regmap_divider_ops);
129 
130 const struct clk_ops clk_regmap_divider_ro_ops = {
131 	.recalc_rate = clk_regmap_div_recalc_rate,
132 	.determine_rate = clk_regmap_div_determine_rate,
133 };
134 EXPORT_SYMBOL_GPL(clk_regmap_divider_ro_ops);
135 
136 static u8 clk_regmap_mux_get_parent(struct clk_hw *hw)
137 {
138 	struct clk_regmap *clk = to_clk_regmap(hw);
139 	struct clk_regmap_mux_data *mux = clk_get_regmap_mux_data(clk);
140 	unsigned int val;
141 	int ret;
142 
143 	ret = regmap_read(clk->map, mux->offset, &val);
144 	if (ret)
145 		return ret;
146 
147 	val >>= mux->shift;
148 	val &= mux->mask;
149 	return clk_mux_val_to_index(hw, mux->table, mux->flags, val);
150 }
151 
152 static int clk_regmap_mux_set_parent(struct clk_hw *hw, u8 index)
153 {
154 	struct clk_regmap *clk = to_clk_regmap(hw);
155 	struct clk_regmap_mux_data *mux = clk_get_regmap_mux_data(clk);
156 	unsigned int val = clk_mux_index_to_val(mux->table, mux->flags, index);
157 
158 	return regmap_update_bits(clk->map, mux->offset,
159 				  mux->mask << mux->shift,
160 				  val << mux->shift);
161 }
162 
163 static int clk_regmap_mux_determine_rate(struct clk_hw *hw,
164 					 struct clk_rate_request *req)
165 {
166 	struct clk_regmap *clk = to_clk_regmap(hw);
167 	struct clk_regmap_mux_data *mux = clk_get_regmap_mux_data(clk);
168 
169 	return clk_mux_determine_rate_flags(hw, req, mux->flags);
170 }
171 
172 const struct clk_ops clk_regmap_mux_ops = {
173 	.get_parent = clk_regmap_mux_get_parent,
174 	.set_parent = clk_regmap_mux_set_parent,
175 	.determine_rate = clk_regmap_mux_determine_rate,
176 };
177 EXPORT_SYMBOL_GPL(clk_regmap_mux_ops);
178 
179 const struct clk_ops clk_regmap_mux_ro_ops = {
180 	.get_parent = clk_regmap_mux_get_parent,
181 };
182 EXPORT_SYMBOL_GPL(clk_regmap_mux_ro_ops);
183 
184 MODULE_DESCRIPTION("Amlogic regmap backed clock driver");
185 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
186 MODULE_LICENSE("GPL v2");
187