Quelle  owl-divider.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0+
//
// OWL divider clock driver
//
// Copyright (c) 2014 Actions Semi Inc.
// Author: David Liu <liuwei@actions-semi.com>
//
// Copyright (c) 2018 Linaro Ltd.
// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

#include <linux/clk-provider.h>
#include <linux/regmap.h>

#include "owl-divider.h"

long owl_divider_helper_round_rate(struct owl_clk_common *common,
    const struct owl_divider_hw *div_hw,
    unsigned long rate,
    unsigned long *parent_rate)
{
 return divider_round_rate(&common->hw, rate, parent_rate,
      div_hw->table, div_hw->width,
      div_hw->div_flags);
}

static long owl_divider_round_rate(struct clk_hw *hw, unsigned long rate,
    unsigned long *parent_rate)
{
 struct owl_divider *div = hw_to_owl_divider(hw);

 return owl_divider_helper_round_rate(&div->common, &div->div_hw,
          rate, parent_rate);
}

unsigned long owl_divider_helper_recalc_rate(struct owl_clk_common *common,
      const struct owl_divider_hw *div_hw,
      unsigned long parent_rate)
{
 unsigned long val;
 unsigned int reg;

 regmap_read(common->regmap, div_hw->reg, ®);
 val = reg >> div_hw->shift;
 val &= (1 << div_hw->width) - 1;

 return divider_recalc_rate(&common->hw, parent_rate,
       val, div_hw->table,
       div_hw->div_flags,
       div_hw->width);
}

static unsigned long owl_divider_recalc_rate(struct clk_hw *hw,
       unsigned long parent_rate)
{
 struct owl_divider *div = hw_to_owl_divider(hw);

 return owl_divider_helper_recalc_rate(&div->common,
           &div->div_hw, parent_rate);
}

int owl_divider_helper_set_rate(const struct owl_clk_common *common,
    const struct owl_divider_hw *div_hw,
    unsigned long rate,
    unsigned long parent_rate)
{
 unsigned long val;
 unsigned int reg;

 val = divider_get_val(rate, parent_rate, div_hw->table,
         div_hw->width, 0);

 regmap_read(common->regmap, div_hw->reg, ®);
 reg &= ~GENMASK(div_hw->width + div_hw->shift - 1, div_hw->shift);

 regmap_write(common->regmap, div_hw->reg,
     reg | (val << div_hw->shift));

 return 0;
}

static int owl_divider_set_rate(struct clk_hw *hw, unsigned long rate,
    unsigned long parent_rate)
{
 struct owl_divider *div = hw_to_owl_divider(hw);

 return owl_divider_helper_set_rate(&div->common, &div->div_hw,
     rate, parent_rate);
}

const struct clk_ops owl_divider_ops = {
 .recalc_rate = owl_divider_recalc_rate,
 .round_rate = owl_divider_round_rate,
 .set_rate = owl_divider_set_rate,
};