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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 | /* * 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/interrupt.h> #include <linux/irq.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/io.h> #include <linux/sched.h> #include <linux/wait.h> #include "pmc.h" #define UTMI_FIXED_MUL 40 struct clk_utmi { struct clk_hw hw; struct at91_pmc *pmc; unsigned int irq; wait_queue_head_t wait; }; #define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw) static irqreturn_t clk_utmi_irq_handler(int irq, void *dev_id) { struct clk_utmi *utmi = (struct clk_utmi *)dev_id; wake_up(&utmi->wait); disable_irq_nosync(utmi->irq); return IRQ_HANDLED; } static int clk_utmi_prepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); struct at91_pmc *pmc = utmi->pmc; u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) | AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT | AT91_PMC_BIASEN; pmc_write(pmc, AT91_CKGR_UCKR, tmp); while (!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU)) { enable_irq(utmi->irq); wait_event(utmi->wait, pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU); } return 0; } static int clk_utmi_is_prepared(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); struct at91_pmc *pmc = utmi->pmc; return !!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU); } static void clk_utmi_unprepare(struct clk_hw *hw) { struct clk_utmi *utmi = to_clk_utmi(hw); struct at91_pmc *pmc = utmi->pmc; u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) & ~AT91_PMC_UPLLEN; pmc_write(pmc, AT91_CKGR_UCKR, tmp); } 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 * __init at91_clk_register_utmi(struct at91_pmc *pmc, unsigned int irq, const char *name, const char *parent_name) { int ret; struct clk_utmi *utmi; struct clk *clk = NULL; struct clk_init_data init; 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->pmc = pmc; utmi->irq = irq; init_waitqueue_head(&utmi->wait); irq_set_status_flags(utmi->irq, IRQ_NOAUTOEN); ret = request_irq(utmi->irq, clk_utmi_irq_handler, IRQF_TRIGGER_HIGH, "clk-utmi", utmi); if (ret) return ERR_PTR(ret); clk = clk_register(NULL, &utmi->hw); if (IS_ERR(clk)) kfree(utmi); return clk; } static void __init of_at91_clk_utmi_setup(struct device_node *np, struct at91_pmc *pmc) { unsigned int irq; struct clk *clk; const char *parent_name; const char *name = np->name; parent_name = of_clk_get_parent_name(np, 0); of_property_read_string(np, "clock-output-names", &name); irq = irq_of_parse_and_map(np, 0); if (!irq) return; clk = at91_clk_register_utmi(pmc, irq, name, parent_name); if (IS_ERR(clk)) return; of_clk_add_provider(np, of_clk_src_simple_get, clk); return; } void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np, struct at91_pmc *pmc) { of_at91_clk_utmi_setup(np, pmc); } |