xref: /openbmc/linux/drivers/clk/mediatek/clk-mux.c (revision 82df5b73)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2018 MediaTek Inc.
4  * Author: Owen Chen <owen.chen@mediatek.com>
5  */
6 
7 #include <linux/of.h>
8 #include <linux/of_address.h>
9 #include <linux/slab.h>
10 #include <linux/mfd/syscon.h>
11 
12 #include "clk-mtk.h"
13 #include "clk-mux.h"
14 
15 static inline struct mtk_clk_mux *to_mtk_clk_mux(struct clk_hw *hw)
16 {
17 	return container_of(hw, struct mtk_clk_mux, hw);
18 }
19 
20 static int mtk_clk_mux_enable(struct clk_hw *hw)
21 {
22 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
23 	u32 mask = BIT(mux->data->gate_shift);
24 
25 	return regmap_update_bits(mux->regmap, mux->data->mux_ofs,
26 			mask, ~mask);
27 }
28 
29 static void mtk_clk_mux_disable(struct clk_hw *hw)
30 {
31 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
32 	u32 mask = BIT(mux->data->gate_shift);
33 
34 	regmap_update_bits(mux->regmap, mux->data->mux_ofs, mask, mask);
35 }
36 
37 static int mtk_clk_mux_enable_setclr(struct clk_hw *hw)
38 {
39 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
40 
41 	return regmap_write(mux->regmap, mux->data->clr_ofs,
42 			BIT(mux->data->gate_shift));
43 }
44 
45 static void mtk_clk_mux_disable_setclr(struct clk_hw *hw)
46 {
47 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
48 
49 	regmap_write(mux->regmap, mux->data->set_ofs,
50 			BIT(mux->data->gate_shift));
51 }
52 
53 static int mtk_clk_mux_is_enabled(struct clk_hw *hw)
54 {
55 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
56 	u32 val;
57 
58 	regmap_read(mux->regmap, mux->data->mux_ofs, &val);
59 
60 	return (val & BIT(mux->data->gate_shift)) == 0;
61 }
62 
63 static u8 mtk_clk_mux_get_parent(struct clk_hw *hw)
64 {
65 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
66 	u32 mask = GENMASK(mux->data->mux_width - 1, 0);
67 	u32 val;
68 
69 	regmap_read(mux->regmap, mux->data->mux_ofs, &val);
70 	val = (val >> mux->data->mux_shift) & mask;
71 
72 	return val;
73 }
74 
75 static int mtk_clk_mux_set_parent_lock(struct clk_hw *hw, u8 index)
76 {
77 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
78 	u32 mask = GENMASK(mux->data->mux_width - 1, 0);
79 	unsigned long flags = 0;
80 
81 	if (mux->lock)
82 		spin_lock_irqsave(mux->lock, flags);
83 	else
84 		__acquire(mux->lock);
85 
86 	regmap_update_bits(mux->regmap, mux->data->mux_ofs, mask,
87 		index << mux->data->mux_shift);
88 
89 	if (mux->lock)
90 		spin_unlock_irqrestore(mux->lock, flags);
91 	else
92 		__release(mux->lock);
93 
94 	return 0;
95 }
96 
97 static int mtk_clk_mux_set_parent_setclr_lock(struct clk_hw *hw, u8 index)
98 {
99 	struct mtk_clk_mux *mux = to_mtk_clk_mux(hw);
100 	u32 mask = GENMASK(mux->data->mux_width - 1, 0);
101 	u32 val, orig;
102 	unsigned long flags = 0;
103 
104 	if (mux->lock)
105 		spin_lock_irqsave(mux->lock, flags);
106 	else
107 		__acquire(mux->lock);
108 
109 	regmap_read(mux->regmap, mux->data->mux_ofs, &orig);
110 	val = (orig & ~(mask << mux->data->mux_shift))
111 			| (index << mux->data->mux_shift);
112 
113 	if (val != orig) {
114 		regmap_write(mux->regmap, mux->data->clr_ofs,
115 				mask << mux->data->mux_shift);
116 		regmap_write(mux->regmap, mux->data->set_ofs,
117 				index << mux->data->mux_shift);
118 
119 		if (mux->data->upd_shift >= 0)
120 			regmap_write(mux->regmap, mux->data->upd_ofs,
121 					BIT(mux->data->upd_shift));
122 	}
123 
124 	if (mux->lock)
125 		spin_unlock_irqrestore(mux->lock, flags);
126 	else
127 		__release(mux->lock);
128 
129 	return 0;
130 }
131 
132 const struct clk_ops mtk_mux_ops = {
133 	.get_parent = mtk_clk_mux_get_parent,
134 	.set_parent = mtk_clk_mux_set_parent_lock,
135 };
136 
137 const struct clk_ops mtk_mux_clr_set_upd_ops = {
138 	.get_parent = mtk_clk_mux_get_parent,
139 	.set_parent = mtk_clk_mux_set_parent_setclr_lock,
140 };
141 
142 const struct clk_ops mtk_mux_gate_ops = {
143 	.enable = mtk_clk_mux_enable,
144 	.disable = mtk_clk_mux_disable,
145 	.is_enabled = mtk_clk_mux_is_enabled,
146 	.get_parent = mtk_clk_mux_get_parent,
147 	.set_parent = mtk_clk_mux_set_parent_lock,
148 };
149 
150 const struct clk_ops mtk_mux_gate_clr_set_upd_ops = {
151 	.enable = mtk_clk_mux_enable_setclr,
152 	.disable = mtk_clk_mux_disable_setclr,
153 	.is_enabled = mtk_clk_mux_is_enabled,
154 	.get_parent = mtk_clk_mux_get_parent,
155 	.set_parent = mtk_clk_mux_set_parent_setclr_lock,
156 };
157 
158 struct clk *mtk_clk_register_mux(const struct mtk_mux *mux,
159 				 struct regmap *regmap,
160 				 spinlock_t *lock)
161 {
162 	struct mtk_clk_mux *clk_mux;
163 	struct clk_init_data init = {};
164 	struct clk *clk;
165 
166 	clk_mux = kzalloc(sizeof(*clk_mux), GFP_KERNEL);
167 	if (!clk_mux)
168 		return ERR_PTR(-ENOMEM);
169 
170 	init.name = mux->name;
171 	init.flags = mux->flags | CLK_SET_RATE_PARENT;
172 	init.parent_names = mux->parent_names;
173 	init.num_parents = mux->num_parents;
174 	init.ops = mux->ops;
175 
176 	clk_mux->regmap = regmap;
177 	clk_mux->data = mux;
178 	clk_mux->lock = lock;
179 	clk_mux->hw.init = &init;
180 
181 	clk = clk_register(NULL, &clk_mux->hw);
182 	if (IS_ERR(clk)) {
183 		kfree(clk_mux);
184 		return clk;
185 	}
186 
187 	return clk;
188 }
189 
190 int mtk_clk_register_muxes(const struct mtk_mux *muxes,
191 			   int num, struct device_node *node,
192 			   spinlock_t *lock,
193 			   struct clk_onecell_data *clk_data)
194 {
195 	struct regmap *regmap;
196 	struct clk *clk;
197 	int i;
198 
199 	regmap = syscon_node_to_regmap(node);
200 	if (IS_ERR(regmap)) {
201 		pr_err("Cannot find regmap for %pOF: %ld\n", node,
202 		       PTR_ERR(regmap));
203 		return PTR_ERR(regmap);
204 	}
205 
206 	for (i = 0; i < num; i++) {
207 		const struct mtk_mux *mux = &muxes[i];
208 
209 		if (IS_ERR_OR_NULL(clk_data->clks[mux->id])) {
210 			clk = mtk_clk_register_mux(mux, regmap, lock);
211 
212 			if (IS_ERR(clk)) {
213 				pr_err("Failed to register clk %s: %ld\n",
214 				       mux->name, PTR_ERR(clk));
215 				continue;
216 			}
217 
218 			clk_data->clks[mux->id] = clk;
219 		}
220 	}
221 
222 	return 0;
223 }
224