arch/arm/mach-omap2/clkt2xxx_dpll.c

   1 /*
   2  * OMAP2-specific DPLL control functions
   3  *
   4  * Copyright (C) 2011 Nokia Corporation
   5  * Paul Walmsley
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/clk.h>
  15 #include <linux/io.h>
  16
  17 #include <plat/clock.h>
  18
  19 #include "clock.h"
  20 #include "cm2xxx_3xxx.h"
  21 #include "cm-regbits-24xx.h"
  22
  23 /* Private functions */
  24
  25 /**
  26  * _allow_idle - enable DPLL autoidle bits
  27  * @clk: struct clk * of the DPLL to operate on
  28  *
  29  * Enable DPLL automatic idle control.  The DPLL will enter low-power
  30  * stop when its downstream clocks are gated.  No return value.
  31  * REVISIT: DPLL can optionally enter low-power bypass by writing 0x1
  32  * instead.  Add some mechanism to optionally enter this mode.
  33  */
  34 static void _allow_idle(struct clk *clk)
  35 {
  36         if (!clk || !clk->dpll_data)
  37                 return;
  38
  39         omap2xxx_cm_set_dpll_auto_low_power_stop();
  40 }
  41
  42 /**
  43  * _deny_idle - prevent DPLL from automatically idling
  44  * @clk: struct clk * of the DPLL to operate on
  45  *
  46  * Disable DPLL automatic idle control.  No return value.
  47  */
  48 static void _deny_idle(struct clk *clk)
  49 {
  50         if (!clk || !clk->dpll_data)
  51                 return;
  52
  53         omap2xxx_cm_set_dpll_disable_autoidle();
  54 }
  55
  56
  57 /* Public data */
  58
  59 const struct clkops clkops_omap2xxx_dpll_ops = {
  60         .allow_idle     = _allow_idle,
  61         .deny_idle      = _deny_idle,
  62 };
  63