text: /*
   * Copyright (C) 2016 Maxime Ripard
   * Maxime Ripard <maxime.ripard@free-electrons.com>
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
   * published by the Free Software Foundation; either version 2 of
   * the License, or (at your option) any later version.
   */
  
  #include <linux/clk-provider.h>
  #include <linux/spinlock.h>
  
  #include "ccu_frac.h"
  
  bool ccu_frac_helper_is_enabled(struct ccu_common *common,
  				struct ccu_frac_internal *cf)
  {
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return false;
  
  	return !(readl(common->base + common->reg) & cf->enable);
  }
  
  void ccu_frac_helper_enable(struct ccu_common *common,
  			    struct ccu_frac_internal *cf)
  {
  	unsigned long flags;
  	u32 reg;
  
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return;
  
  	spin_lock_irqsave(common->lock, flags);
  	reg = readl(common->base + common->reg);
  	writel(reg & ~cf->enable, common->base + common->reg);
  	spin_unlock_irqrestore(common->lock, flags);
  }
  
  void ccu_frac_helper_disable(struct ccu_common *common,
  			     struct ccu_frac_internal *cf)
  {
  	unsigned long flags;
  	u32 reg;
  
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return;
  
  	spin_lock_irqsave(common->lock, flags);
  	reg = readl(common->base + common->reg);
  	writel(reg | cf->enable, common->base + common->reg);
  	spin_unlock_irqrestore(common->lock, flags);
  }
  
  bool ccu_frac_helper_has_rate(struct ccu_common *common,
  			      struct ccu_frac_internal *cf,
  			      unsigned long rate)
  {
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return false;
  
  	return (cf->rates[0] == rate) || (cf->rates[1] == rate);
  }
  
  unsigned long ccu_frac_helper_read_rate(struct ccu_common *common,
  					struct ccu_frac_internal *cf)
  {
  	u32 reg;
  
  	pr_debug("%s: Read fractional\n", clk_hw_get_name(&common->hw));
  
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return 0;
  
  	pr_debug("%s: clock is fractional (rates %lu and %lu)\n",
  		 clk_hw_get_name(&common->hw), cf->rates[0], cf->rates[1]);
  
  	reg = readl(common->base + common->reg);
  
  	pr_debug("%s: clock reg is 0x%x (select is 0x%x)\n",
  		 clk_hw_get_name(&common->hw), reg, cf->select);
  
  	return (reg & cf->select) ? cf->rates[1] : cf->rates[0];
  }
  
  int ccu_frac_helper_set_rate(struct ccu_common *common,
  			     struct ccu_frac_internal *cf,
  			     unsigned long rate, u32 lock)
  {
  	unsigned long flags;
  	u32 reg, sel;
  
  	if (!(common->features & CCU_FEATURE_FRACTIONAL))
  		return -EINVAL;
  
  	if (cf->rates[0] == rate)
  		sel = 0;
  	else if (cf->rates[1] == rate)
  		sel = cf->select;
  	else
  		return -EINVAL;
  
  	spin_lock_irqsave(common->lock, flags);
  	reg = readl(common->base + common->reg);
  	reg &= ~cf->select;
  	writel(reg | sel, common->base + common->reg);
  	spin_unlock_irqrestore(common->lock, flags);
  
  	ccu_helper_wait_for_lock(common, lock);
  
  	return 0;
  }
  