linux/drivers/clk/meson/clk-phase.c

64 lines
1.6 KiB
C

// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/*
* Copyright (c) 2018 BayLibre, SAS.
* Author: Jerome Brunet <jbrunet@baylibre.com>
*/
#include <linux/clk-provider.h>
#include "clkc.h"
#define phase_step(_width) (360 / (1 << (_width)))
static inline struct meson_clk_phase_data *
meson_clk_phase_data(struct clk_regmap *clk)
{
return (struct meson_clk_phase_data *)clk->data;
}
int meson_clk_degrees_from_val(unsigned int val, unsigned int width)
{
return phase_step(width) * val;
}
EXPORT_SYMBOL_GPL(meson_clk_degrees_from_val);
unsigned int meson_clk_degrees_to_val(int degrees, unsigned int width)
{
unsigned int val = DIV_ROUND_CLOSEST(degrees, phase_step(width));
/*
* This last calculation is here for cases when degrees is rounded
* to 360, in which case val == (1 << width).
*/
return val % (1 << width);
}
EXPORT_SYMBOL_GPL(meson_clk_degrees_to_val);
static int meson_clk_phase_get_phase(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_phase_data *phase = meson_clk_phase_data(clk);
unsigned int val;
val = meson_parm_read(clk->map, &phase->ph);
return meson_clk_degrees_from_val(val, phase->ph.width);
}
static int meson_clk_phase_set_phase(struct clk_hw *hw, int degrees)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_phase_data *phase = meson_clk_phase_data(clk);
unsigned int val;
val = meson_clk_degrees_to_val(degrees, phase->ph.width);
meson_parm_write(clk->map, &phase->ph, val);
return 0;
}
const struct clk_ops meson_clk_phase_ops = {
.get_phase = meson_clk_phase_get_phase,
.set_phase = meson_clk_phase_set_phase,
};
EXPORT_SYMBOL_GPL(meson_clk_phase_ops);