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 "clock.h"
  18 #include "cm2xxx_3xxx.h"
  19 #include "cm-regbits-24xx.h"
  20
  21 /* Private functions */
  22
  23 /**
  24  * _allow_idle - enable DPLL autoidle bits
  25  * @clk: struct clk * of the DPLL to operate on
  26  *
  27  * Enable DPLL automatic idle control.  The DPLL will enter low-power
  28  * stop when its downstream clocks are gated.  No return value.
  29  * REVISIT: DPLL can optionally enter low-power bypass by writing 0x1
  30  * instead.  Add some mechanism to optionally enter this mode.
  31  */
  32 static void _allow_idle(struct clk *clk)
  33 {
  34         if (!clk || !clk->dpll_data)
  35                 return;
  36
  37         omap2xxx_cm_set_dpll_auto_low_power_stop();
  38 }
  39
  40 /**
  41  * _deny_idle - prevent DPLL from automatically idling
  42  * @clk: struct clk * of the DPLL to operate on
  43  *
  44  * Disable DPLL automatic idle control.  No return value.
  45  */
  46 static void _deny_idle(struct clk *clk)
  47 {
  48         if (!clk || !clk->dpll_data)
  49                 return;
  50
  51         omap2xxx_cm_set_dpll_disable_autoidle();
  52 }
  53
  54
  55 /* Public data */
  56
  57 const struct clkops clkops_omap2xxx_dpll_ops = {
  58         .allow_idle     = _allow_idle,
  59         .deny_idle      = _deny_idle,
  60 };
  61