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 MODULE_DESCRIPTION("Amlogic phase driver"); 129 MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>"); 130 MODULE_LICENSE("GPL v2"); 131