153 строки
3.0 KiB
C
153 строки
3.0 KiB
C
/*
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* Clock management for AT32AP CPUs
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*
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* Copyright (C) 2006 Atmel Corporation
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*
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* Based on arch/arm/mach-at91/clock.c
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* Copyright (C) 2005 David Brownell
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* Copyright (C) 2005 Ivan Kokshaysky
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/clk.h>
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#include <linux/err.h>
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#include <linux/device.h>
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#include <linux/string.h>
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#include "clock.h"
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static spinlock_t clk_lock = SPIN_LOCK_UNLOCKED;
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struct clk *clk_get(struct device *dev, const char *id)
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{
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int i;
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for (i = 0; i < at32_nr_clocks; i++) {
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struct clk *clk = at32_clock_list[i];
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if (clk->dev == dev && strcmp(id, clk->name) == 0)
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return clk;
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}
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return ERR_PTR(-ENOENT);
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}
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EXPORT_SYMBOL(clk_get);
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void clk_put(struct clk *clk)
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{
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/* clocks are static for now, we can't free them */
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}
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EXPORT_SYMBOL(clk_put);
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static void __clk_enable(struct clk *clk)
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{
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if (clk->parent)
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__clk_enable(clk->parent);
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if (clk->users++ == 0 && clk->mode)
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clk->mode(clk, 1);
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}
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int clk_enable(struct clk *clk)
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{
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unsigned long flags;
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spin_lock_irqsave(&clk_lock, flags);
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__clk_enable(clk);
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spin_unlock_irqrestore(&clk_lock, flags);
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return 0;
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}
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EXPORT_SYMBOL(clk_enable);
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static void __clk_disable(struct clk *clk)
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{
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if (clk->users == 0) {
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printk(KERN_ERR "%s: mismatched disable\n", clk->name);
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WARN_ON(1);
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return;
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}
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if (--clk->users == 0 && clk->mode)
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clk->mode(clk, 0);
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if (clk->parent)
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__clk_disable(clk->parent);
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}
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void clk_disable(struct clk *clk)
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{
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unsigned long flags;
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spin_lock_irqsave(&clk_lock, flags);
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__clk_disable(clk);
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spin_unlock_irqrestore(&clk_lock, flags);
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}
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EXPORT_SYMBOL(clk_disable);
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unsigned long clk_get_rate(struct clk *clk)
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{
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unsigned long flags;
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unsigned long rate;
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spin_lock_irqsave(&clk_lock, flags);
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rate = clk->get_rate(clk);
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spin_unlock_irqrestore(&clk_lock, flags);
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return rate;
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}
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EXPORT_SYMBOL(clk_get_rate);
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long clk_round_rate(struct clk *clk, unsigned long rate)
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{
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unsigned long flags, actual_rate;
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if (!clk->set_rate)
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return -ENOSYS;
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spin_lock_irqsave(&clk_lock, flags);
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actual_rate = clk->set_rate(clk, rate, 0);
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spin_unlock_irqrestore(&clk_lock, flags);
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return actual_rate;
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}
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EXPORT_SYMBOL(clk_round_rate);
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int clk_set_rate(struct clk *clk, unsigned long rate)
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{
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unsigned long flags;
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long ret;
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if (!clk->set_rate)
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return -ENOSYS;
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spin_lock_irqsave(&clk_lock, flags);
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ret = clk->set_rate(clk, rate, 1);
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spin_unlock_irqrestore(&clk_lock, flags);
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return (ret < 0) ? ret : 0;
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}
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EXPORT_SYMBOL(clk_set_rate);
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int clk_set_parent(struct clk *clk, struct clk *parent)
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{
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unsigned long flags;
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int ret;
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if (!clk->set_parent)
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return -ENOSYS;
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spin_lock_irqsave(&clk_lock, flags);
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ret = clk->set_parent(clk, parent);
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spin_unlock_irqrestore(&clk_lock, flags);
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return ret;
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}
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EXPORT_SYMBOL(clk_set_parent);
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struct clk *clk_get_parent(struct clk *clk)
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{
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return clk->parent;
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}
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EXPORT_SYMBOL(clk_get_parent);
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