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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 | /* * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * */ #include <linux/clk-provider.h> #include <linux/clkdev.h> #include <linux/clk/at91_pmc.h> #include <linux/of.h> #include <linux/mfd/syscon.h> #include <linux/regmap.h> #include "pmc.h" #define UTMI_FIXED_MUL 40 struct clk_utmi { struct clk_hw hw; struct regmap *regmap; }; #define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw) static inline bool clk_utmi_ready(struct regmap *regmap) { unsigned int status; regmap_read(regmap, AT91_PMC_SR, &status); return status & AT91_PMC_LOCKU; } static int clk_utmi_prepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); unsigned int uckr = AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT | AT91_PMC_BIASEN; regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, uckr, uckr); while (!clk_utmi_ready(utmi->regmap)) cpu_relax(); return 0; } static int clk_utmi_is_prepared(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); return clk_utmi_ready(utmi->regmap); } static void clk_utmi_unprepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0); } static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { /* UTMI clk is a fixed clk multiplier */ return parent_rate * UTMI_FIXED_MUL; } static const struct clk_ops utmi_ops = { .prepare = clk_utmi_prepare, .unprepare = clk_utmi_unprepare, .is_prepared = clk_utmi_is_prepared, .recalc_rate = clk_utmi_recalc_rate, }; static struct clk_hw * __init at91_clk_register_utmi(struct regmap *regmap, const char *name, const char *parent_name) { struct clk_utmi *utmi; struct clk_hw *hw; struct clk_init_data init; int ret; utmi = kzalloc(sizeof(*utmi), GFP_KERNEL); if (!utmi) return ERR_PTR(-ENOMEM); init.name = name; init.ops = &utmi_ops; init.parent_names = parent_name ? &parent_name : NULL; init.num_parents = parent_name ? 1 : 0; init.flags = CLK_SET_RATE_GATE; utmi->hw.init = &init; utmi->regmap = regmap; hw = &utmi->hw; ret = clk_hw_register(NULL, &utmi->hw); if (ret) { kfree(utmi); hw = ERR_PTR(ret); } return hw; } static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np) { struct clk_hw *hw; const char *parent_name; const char *name = np->name; struct regmap *regmap; parent_name = of_clk_get_parent_name(np, 0); of_property_read_string(np, "clock-output-names", &name); regmap = syscon_node_to_regmap(of_get_parent(np)); if (IS_ERR(regmap)) return; hw = at91_clk_register_utmi(regmap, name, parent_name); if (IS_ERR(hw)) return; of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw); return; } CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi", of_at91sam9x5_clk_utmi_setup); |