arch/arm/mach-mmp/clock.c

   1 /*
   2  *  linux/arch/arm/mach-mmp/clock.c
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License version 2 as
   6  *  published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/kernel.h>
  11 #include <linux/list.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/clk.h>
  14 #include <linux/io.h>
  15
  16 #include "regs-apbc.h"
  17 #include "clock.h"
  18
  19 static void apbc_clk_enable(struct clk *clk)
  20 {
  21         uint32_t clk_rst;
  22
  23         clk_rst = APBC_APBCLK | APBC_FNCLK | APBC_FNCLKSEL(clk->fnclksel);
  24         __raw_writel(clk_rst, clk->clk_rst);
  25 }
  26
  27 static void apbc_clk_disable(struct clk *clk)
  28 {
  29         __raw_writel(0, clk->clk_rst);
  30 }
  31
  32 struct clkops apbc_clk_ops = {
  33         .enable         = apbc_clk_enable,
  34         .disable        = apbc_clk_disable,
  35 };
  36
  37 static void apmu_clk_enable(struct clk *clk)
  38 {
  39         __raw_writel(clk->enable_val, clk->clk_rst);
  40 }
  41
  42 static void apmu_clk_disable(struct clk *clk)
  43 {
  44         __raw_writel(0, clk->clk_rst);
  45 }
  46
  47 struct clkops apmu_clk_ops = {
  48         .enable         = apmu_clk_enable,
  49         .disable        = apmu_clk_disable,
  50 };
  51
  52 static DEFINE_SPINLOCK(clocks_lock);
  53
  54 int clk_enable(struct clk *clk)
  55 {
  56         unsigned long flags;
  57
  58         spin_lock_irqsave(&clocks_lock, flags);
  59         if (clk->enabled++ == 0)
  60                 clk->ops->enable(clk);
  61         spin_unlock_irqrestore(&clocks_lock, flags);
  62         return 0;
  63 }
  64 EXPORT_SYMBOL(clk_enable);
  65
  66 void clk_disable(struct clk *clk)
  67 {
  68         unsigned long flags;
  69
  70         if (!clk)
  71                 return;
  72
  73         WARN_ON(clk->enabled == 0);
  74
  75         spin_lock_irqsave(&clocks_lock, flags);
  76         if (--clk->enabled == 0)
  77                 clk->ops->disable(clk);
  78         spin_unlock_irqrestore(&clocks_lock, flags);
  79 }
  80 EXPORT_SYMBOL(clk_disable);
  81
  82 unsigned long clk_get_rate(struct clk *clk)
  83 {
  84         unsigned long rate;
  85
  86         if (clk->ops->getrate)
  87                 rate = clk->ops->getrate(clk);
  88         else
  89                 rate = clk->rate;
  90
  91         return rate;
  92 }
  93 EXPORT_SYMBOL(clk_get_rate);
  94
  95 int clk_set_rate(struct clk *clk, unsigned long rate)
  96 {
  97         unsigned long flags;
  98         int ret = -EINVAL;
  99
 100         if (clk->ops->setrate) {
 101                 spin_lock_irqsave(&clocks_lock, flags);
 102                 ret = clk->ops->setrate(clk, rate);
 103                 spin_unlock_irqrestore(&clocks_lock, flags);
 104         }
 105
 106         return ret;
 107 }
 108 EXPORT_SYMBOL(clk_set_rate);