arch/m68k/platform/coldfire/clk.c

   1 /***************************************************************************/
   2
   3 /*
   4  *      clk.c -- general ColdFire CPU kernel clk handling
   5  *
   6  *      Copyright (C) 2009, Greg Ungerer (gerg@snapgear.com)
   7  */
   8
   9 /***************************************************************************/
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <linux/mutex.h>
  15 #include <linux/clk.h>
  16 #include <linux/io.h>
  17 #include <linux/err.h>
  18 #include <asm/coldfire.h>
  19 #include <asm/mcfsim.h>
  20 #include <asm/mcfclk.h>
  21
  22 /***************************************************************************/
  23 #ifndef MCFPM_PPMCR0
  24 struct clk *clk_get(struct device *dev, const char *id)
  25 {
  26         return NULL;
  27 }
  28 EXPORT_SYMBOL(clk_get);
  29
  30 int clk_enable(struct clk *clk)
  31 {
  32         return 0;
  33 }
  34 EXPORT_SYMBOL(clk_enable);
  35
  36 void clk_disable(struct clk *clk)
  37 {
  38 }
  39 EXPORT_SYMBOL(clk_disable);
  40
  41 void clk_put(struct clk *clk)
  42 {
  43 }
  44 EXPORT_SYMBOL(clk_put);
  45
  46 unsigned long clk_get_rate(struct clk *clk)
  47 {
  48         return MCF_CLK;
  49 }
  50 EXPORT_SYMBOL(clk_get_rate);
  51 #else
  52 static DEFINE_SPINLOCK(clk_lock);
  53
  54 struct clk *clk_get(struct device *dev, const char *id)
  55 {
  56         const char *clk_name = dev ? dev_name(dev) : id ? id : NULL;
  57         struct clk *clk;
  58         unsigned i;
  59
  60         for (i = 0; (clk = mcf_clks[i]) != NULL; ++i)
  61                 if (!strcmp(clk->name, clk_name))
  62                         return clk;
  63         pr_warn("clk_get: didn't find clock %s\n", clk_name);
  64         return ERR_PTR(-ENOENT);
  65 }
  66 EXPORT_SYMBOL(clk_get);
  67
  68 int clk_enable(struct clk *clk)
  69 {
  70         unsigned long flags;
  71         spin_lock_irqsave(&clk_lock, flags);
  72         if ((clk->enabled++ == 0) && clk->clk_ops)
  73                 clk->clk_ops->enable(clk);
  74         spin_unlock_irqrestore(&clk_lock, flags);
  75
  76         return 0;
  77 }
  78 EXPORT_SYMBOL(clk_enable);
  79
  80 void clk_disable(struct clk *clk)
  81 {
  82         unsigned long flags;
  83         spin_lock_irqsave(&clk_lock, flags);
  84         if ((--clk->enabled == 0) && clk->clk_ops)
  85                 clk->clk_ops->disable(clk);
  86         spin_unlock_irqrestore(&clk_lock, flags);
  87 }
  88 EXPORT_SYMBOL(clk_disable);
  89
  90 void clk_put(struct clk *clk)
  91 {
  92         if (clk->enabled != 0)
  93                 pr_warn("clk_put %s still enabled\n", clk->name);
  94 }
  95 EXPORT_SYMBOL(clk_put);
  96
  97 unsigned long clk_get_rate(struct clk *clk)
  98 {
  99         return clk->rate;
 100 }
 101 EXPORT_SYMBOL(clk_get_rate);
 102
 103 /***************************************************************************/
 104
 105 void __clk_init_enabled(struct clk *clk)
 106 {
 107         clk->enabled = 1;
 108         clk->clk_ops->enable(clk);
 109 }
 110
 111 void __clk_init_disabled(struct clk *clk)
 112 {
 113         clk->enabled = 0;
 114         clk->clk_ops->disable(clk);
 115 }
 116
 117 static void __clk_enable0(struct clk *clk)
 118 {
 119         __raw_writeb(clk->slot, MCFPM_PPMCR0);
 120 }
 121
 122 static void __clk_disable0(struct clk *clk)
 123 {
 124         __raw_writeb(clk->slot, MCFPM_PPMSR0);
 125 }
 126
 127 struct clk_ops clk_ops0 = {
 128         .enable         = __clk_enable0,
 129         .disable        = __clk_disable0,
 130 };
 131
 132 #ifdef MCFPM_PPMCR1
 133 static void __clk_enable1(struct clk *clk)
 134 {
 135         __raw_writeb(clk->slot, MCFPM_PPMCR1);
 136 }
 137
 138 static void __clk_disable1(struct clk *clk)
 139 {
 140         __raw_writeb(clk->slot, MCFPM_PPMSR1);
 141 }
 142
 143 struct clk_ops clk_ops1 = {
 144         .enable         = __clk_enable1,
 145         .disable        = __clk_disable1,
 146 };
 147 #endif /* MCFPM_PPMCR1 */
 148 #endif /* MCFPM_PPMCR0 */
 149
 150 struct clk *devm_clk_get(struct device *dev, const char *id)
 151 {
 152         return NULL;
 153 }
 154 EXPORT_SYMBOL(devm_clk_get);