xref: /openbmc/linux/drivers/clk/meson/clk-phase.c (revision fbb6b31a)
1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
2 /*
3  * Copyright (c) 2018 BayLibre, SAS.
4  * Author: Jerome Brunet <jbrunet@baylibre.com>
5  */
6 
7 #include <linux/clk-provider.h>
8 #include <linux/module.h>
9 
10 #include "clk-regmap.h"
11 #include "clk-phase.h"
12 
13 #define phase_step(_width) (360 / (1 << (_width)))
14 
15 static inline struct meson_clk_phase_data *
16 meson_clk_phase_data(struct clk_regmap *clk)
17 {
18 	return (struct meson_clk_phase_data *)clk->data;
19 }
20 
21 static int meson_clk_degrees_from_val(unsigned int val, unsigned int width)
22 {
23 	return phase_step(width) * val;
24 }
25 
26 static unsigned int meson_clk_degrees_to_val(int degrees, unsigned int width)
27 {
28 	unsigned int val = DIV_ROUND_CLOSEST(degrees, phase_step(width));
29 
30 	/*
31 	 * This last calculation is here for cases when degrees is rounded
32 	 * to 360, in which case val == (1 << width).
33 	 */
34 	return val % (1 << width);
35 }
36 
37 static int meson_clk_phase_get_phase(struct clk_hw *hw)
38 {
39 	struct clk_regmap *clk = to_clk_regmap(hw);
40 	struct meson_clk_phase_data *phase = meson_clk_phase_data(clk);
41 	unsigned int val;
42 
43 	val = meson_parm_read(clk->map, &phase->ph);
44 
45 	return meson_clk_degrees_from_val(val, phase->ph.width);
46 }
47 
48 static int meson_clk_phase_set_phase(struct clk_hw *hw, int degrees)
49 {
50 	struct clk_regmap *clk = to_clk_regmap(hw);
51 	struct meson_clk_phase_data *phase = meson_clk_phase_data(clk);
52 	unsigned int val;
53 
54 	val = meson_clk_degrees_to_val(degrees, phase->ph.width);
55 	meson_parm_write(clk->map, &phase->ph, val);
56 
57 	return 0;
58 }
59 
60 const struct clk_ops meson_clk_phase_ops = {
61 	.get_phase	= meson_clk_phase_get_phase,
62 	.set_phase	= meson_clk_phase_set_phase,
63 };
64 EXPORT_SYMBOL_GPL(meson_clk_phase_ops);
65 
66 /*
67  * This is a special clock for the audio controller.
68  * The phase of mst_sclk clock output can be controlled independently
69  * for the outside world (ph0), the tdmout (ph1) and tdmin (ph2).
70  * Controlling these 3 phases as just one makes things simpler and
71  * give the same clock view to all the element on the i2s bus.
72  * If necessary, we can still control the phase in the tdm block
73  * which makes these independent control redundant.
74  */
75 static inline struct meson_clk_triphase_data *
76 meson_clk_triphase_data(struct clk_regmap *clk)
77 {
78 	return (struct meson_clk_triphase_data *)clk->data;
79 }
80 
81 static int meson_clk_triphase_sync(struct clk_hw *hw)
82 {
83 	struct clk_regmap *clk = to_clk_regmap(hw);
84 	struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
85 	unsigned int val;
86 
87 	/* Get phase 0 and sync it to phase 1 and 2 */
88 	val = meson_parm_read(clk->map, &tph->ph0);
89 	meson_parm_write(clk->map, &tph->ph1, val);
90 	meson_parm_write(clk->map, &tph->ph2, val);
91 
92 	return 0;
93 }
94 
95 static int meson_clk_triphase_get_phase(struct clk_hw *hw)
96 {
97 	struct clk_regmap *clk = to_clk_regmap(hw);
98 	struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
99 	unsigned int val;
100 
101 	/* Phase are in sync, reading phase 0 is enough */
102 	val = meson_parm_read(clk->map, &tph->ph0);
103 
104 	return meson_clk_degrees_from_val(val, tph->ph0.width);
105 }
106 
107 static int meson_clk_triphase_set_phase(struct clk_hw *hw, int degrees)
108 {
109 	struct clk_regmap *clk = to_clk_regmap(hw);
110 	struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
111 	unsigned int val;
112 
113 	val = meson_clk_degrees_to_val(degrees, tph->ph0.width);
114 	meson_parm_write(clk->map, &tph->ph0, val);
115 	meson_parm_write(clk->map, &tph->ph1, val);
116 	meson_parm_write(clk->map, &tph->ph2, val);
117 
118 	return 0;
119 }
120 
121 const struct clk_ops meson_clk_triphase_ops = {
122 	.init		= meson_clk_triphase_sync,
123 	.get_phase	= meson_clk_triphase_get_phase,
124 	.set_phase	= meson_clk_triphase_set_phase,
125 };
126 EXPORT_SYMBOL_GPL(meson_clk_triphase_ops);
127 
128 /*
129  * This is a special clock for the audio controller.
130  * This drive a bit clock inverter for which the
131  * opposite value of the inverter bit needs to be manually
132  * set into another bit
133  */
134 static inline struct meson_sclk_ws_inv_data *
135 meson_sclk_ws_inv_data(struct clk_regmap *clk)
136 {
137 	return (struct meson_sclk_ws_inv_data *)clk->data;
138 }
139 
140 static int meson_sclk_ws_inv_sync(struct clk_hw *hw)
141 {
142 	struct clk_regmap *clk = to_clk_regmap(hw);
143 	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
144 	unsigned int val;
145 
146 	/* Get phase and sync the inverted value to ws */
147 	val = meson_parm_read(clk->map, &tph->ph);
148 	meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
149 
150 	return 0;
151 }
152 
153 static int meson_sclk_ws_inv_get_phase(struct clk_hw *hw)
154 {
155 	struct clk_regmap *clk = to_clk_regmap(hw);
156 	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
157 	unsigned int val;
158 
159 	val = meson_parm_read(clk->map, &tph->ph);
160 
161 	return meson_clk_degrees_from_val(val, tph->ph.width);
162 }
163 
164 static int meson_sclk_ws_inv_set_phase(struct clk_hw *hw, int degrees)
165 {
166 	struct clk_regmap *clk = to_clk_regmap(hw);
167 	struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
168 	unsigned int val;
169 
170 	val = meson_clk_degrees_to_val(degrees, tph->ph.width);
171 	meson_parm_write(clk->map, &tph->ph, val);
172 	meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
173 	return 0;
174 }
175 
176 const struct clk_ops meson_sclk_ws_inv_ops = {
177 	.init		= meson_sclk_ws_inv_sync,
178 	.get_phase	= meson_sclk_ws_inv_get_phase,
179 	.set_phase	= meson_sclk_ws_inv_set_phase,
180 };
181 EXPORT_SYMBOL_GPL(meson_sclk_ws_inv_ops);
182 
183 
184 MODULE_DESCRIPTION("Amlogic phase driver");
185 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
186 MODULE_LICENSE("GPL v2");
187