arch/arm/mach-w90x900/clock.c

   1 /*
   2  * linux/arch/arm/mach-w90x900/clock.c
   3  *
   4  * Copyright (c) 2008 Nuvoton technology corporation
   5  *
   6  * Wan ZongShun <mcuos.com@gmail.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/list.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/string.h>
  19 #include <linux/clk.h>
  20 #include <linux/spinlock.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/io.h>
  23
  24 #include <mach/hardware.h>
  25
  26 #include "clock.h"
  27
  28 static DEFINE_SPINLOCK(clocks_lock);
  29
  30 int clk_enable(struct clk *clk)
  31 {
  32         unsigned long flags;
  33
  34         spin_lock_irqsave(&clocks_lock, flags);
  35         if (clk->enabled++ == 0)
  36                 (clk->enable)(clk, 1);
  37         spin_unlock_irqrestore(&clocks_lock, flags);
  38
  39         return 0;
  40 }
  41 EXPORT_SYMBOL(clk_enable);
  42
  43 void clk_disable(struct clk *clk)
  44 {
  45         unsigned long flags;
  46
  47         WARN_ON(clk->enabled == 0);
  48
  49         spin_lock_irqsave(&clocks_lock, flags);
  50         if (--clk->enabled == 0)
  51                 (clk->enable)(clk, 0);
  52         spin_unlock_irqrestore(&clocks_lock, flags);
  53 }
  54 EXPORT_SYMBOL(clk_disable);
  55
  56 void w90x900_clk_enable(struct clk *clk, int enable)
  57 {
  58         unsigned int clocks = clk->cken;
  59         unsigned long clken;
  60
  61         clken = __raw_readl(W90X900_VA_CLKPWR);
  62
  63         if (enable)
  64                 clken |= clocks;
  65         else
  66                 clken &= ~clocks;
  67
  68         __raw_writel(clken, W90X900_VA_CLKPWR);
  69 }
  70
  71 void clks_register(struct clk_lookup *clks, size_t num)
  72 {
  73         int i;
  74
  75         for (i = 0; i < num; i++)
  76                 clkdev_add(&clks[i]);
  77 }