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 <mach/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 DEFINE_SPINLOCK(clocks_lock);
  38
  39 int clk_enable(struct clk *clk)
  40 {
  41         unsigned long flags;
  42
  43         spin_lock_irqsave(&clocks_lock, flags);
  44         if (clk->enabled++ == 0)
  45                 clk->ops->enable(clk);
  46         spin_unlock_irqrestore(&clocks_lock, flags);
  47         return 0;
  48 }
  49 EXPORT_SYMBOL(clk_enable);
  50
  51 void clk_disable(struct clk *clk)
  52 {
  53         unsigned long flags;
  54
  55         WARN_ON(clk->enabled == 0);
  56
  57         spin_lock_irqsave(&clocks_lock, flags);
  58         if (--clk->enabled == 0)
  59                 clk->ops->disable(clk);
  60         spin_unlock_irqrestore(&clocks_lock, flags);
  61 }
  62 EXPORT_SYMBOL(clk_disable);
  63
  64 unsigned long clk_get_rate(struct clk *clk)
  65 {
  66         unsigned long rate;
  67
  68         if (clk->ops->getrate)
  69                 rate = clk->ops->getrate(clk);
  70         else
  71                 rate = clk->rate;
  72
  73         return rate;
  74 }
  75 EXPORT_SYMBOL(clk_get_rate);
  76
  77 void clks_register(struct clk_lookup *clks, size_t num)
  78 {
  79         int i;
  80
  81         for (i = 0; i < num; i++)
  82                 clkdev_add(&clks[i]);
  83 }