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 "clkc-audio.h"
9
10 /*
11 * This is a special clock for the audio controller.
12 * The phase of mst_sclk clock output can be controlled independently
13 * for the outside world (ph0), the tdmout (ph1) and tdmin (ph2).
14 * Controlling these 3 phases as just one makes things simpler and
15 * give the same clock view to all the element on the i2s bus.
16 * If necessary, we can still control the phase in the tdm block
17 * which makes these independent control redundant.
18 */
19 static inline struct meson_clk_triphase_data *
meson_clk_triphase_data(struct clk_regmap * clk)20 meson_clk_triphase_data(struct clk_regmap *clk)
21 {
22 return (struct meson_clk_triphase_data *)clk->data;
23 }
24
meson_clk_triphase_sync(struct clk_hw * hw)25 static void meson_clk_triphase_sync(struct clk_hw *hw)
26 {
27 struct clk_regmap *clk = to_clk_regmap(hw);
28 struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
29 unsigned int val;
30
31 /* Get phase 0 and sync it to phase 1 and 2 */
32 val = meson_parm_read(clk->map, &tph->ph0);
33 meson_parm_write(clk->map, &tph->ph1, val);
34 meson_parm_write(clk->map, &tph->ph2, val);
35 }
36
meson_clk_triphase_get_phase(struct clk_hw * hw)37 static int meson_clk_triphase_get_phase(struct clk_hw *hw)
38 {
39 struct clk_regmap *clk = to_clk_regmap(hw);
40 struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
41 unsigned int val;
42
43 /* Phase are in sync, reading phase 0 is enough */
44 val = meson_parm_read(clk->map, &tph->ph0);
45
46 return meson_clk_degrees_from_val(val, tph->ph0.width);
47 }
48
meson_clk_triphase_set_phase(struct clk_hw * hw,int degrees)49 static int meson_clk_triphase_set_phase(struct clk_hw *hw, int degrees)
50 {
51 struct clk_regmap *clk = to_clk_regmap(hw);
52 struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
53 unsigned int val;
54
55 val = meson_clk_degrees_to_val(degrees, tph->ph0.width);
56 meson_parm_write(clk->map, &tph->ph0, val);
57 meson_parm_write(clk->map, &tph->ph1, val);
58 meson_parm_write(clk->map, &tph->ph2, val);
59
60 return 0;
61 }
62
63 const struct clk_ops meson_clk_triphase_ops = {
64 .init = meson_clk_triphase_sync,
65 .get_phase = meson_clk_triphase_get_phase,
66 .set_phase = meson_clk_triphase_set_phase,
67 };
68 EXPORT_SYMBOL_GPL(meson_clk_triphase_ops);
69
