1
linux/drivers/clk/meson/clk-phase.c

187 lines
5.3 KiB
C
Raw Normal View History

// 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 <linux/module.h>
#include "clk-regmap.h"
#include "clk-phase.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;
}
static int meson_clk_degrees_from_val(unsigned int val, unsigned int width)
{
return phase_step(width) * val;
}
static 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);
}
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_NS_GPL(meson_clk_phase_ops, CLK_MESON);
/*
* This is a special clock for the audio controller.
* The phase of mst_sclk clock output can be controlled independently
* for the outside world (ph0), the tdmout (ph1) and tdmin (ph2).
* Controlling these 3 phases as just one makes things simpler and
* give the same clock view to all the element on the i2s bus.
* If necessary, we can still control the phase in the tdm block
* which makes these independent control redundant.
*/
static inline struct meson_clk_triphase_data *
meson_clk_triphase_data(struct clk_regmap *clk)
{
return (struct meson_clk_triphase_data *)clk->data;
}
static int meson_clk_triphase_sync(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
unsigned int val;
/* Get phase 0 and sync it to phase 1 and 2 */
val = meson_parm_read(clk->map, &tph->ph0);
meson_parm_write(clk->map, &tph->ph1, val);
meson_parm_write(clk->map, &tph->ph2, val);
return 0;
}
static int meson_clk_triphase_get_phase(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
unsigned int val;
/* Phase are in sync, reading phase 0 is enough */
val = meson_parm_read(clk->map, &tph->ph0);
return meson_clk_degrees_from_val(val, tph->ph0.width);
}
static int meson_clk_triphase_set_phase(struct clk_hw *hw, int degrees)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_triphase_data *tph = meson_clk_triphase_data(clk);
unsigned int val;
val = meson_clk_degrees_to_val(degrees, tph->ph0.width);
meson_parm_write(clk->map, &tph->ph0, val);
meson_parm_write(clk->map, &tph->ph1, val);
meson_parm_write(clk->map, &tph->ph2, val);
return 0;
}
const struct clk_ops meson_clk_triphase_ops = {
.init = meson_clk_triphase_sync,
.get_phase = meson_clk_triphase_get_phase,
.set_phase = meson_clk_triphase_set_phase,
};
EXPORT_SYMBOL_NS_GPL(meson_clk_triphase_ops, CLK_MESON);
/*
* This is a special clock for the audio controller.
* This drive a bit clock inverter for which the
* opposite value of the inverter bit needs to be manually
* set into another bit
*/
static inline struct meson_sclk_ws_inv_data *
meson_sclk_ws_inv_data(struct clk_regmap *clk)
{
return (struct meson_sclk_ws_inv_data *)clk->data;
}
static int meson_sclk_ws_inv_sync(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
unsigned int val;
/* Get phase and sync the inverted value to ws */
val = meson_parm_read(clk->map, &tph->ph);
meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
return 0;
}
static int meson_sclk_ws_inv_get_phase(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
unsigned int val;
val = meson_parm_read(clk->map, &tph->ph);
return meson_clk_degrees_from_val(val, tph->ph.width);
}
static int meson_sclk_ws_inv_set_phase(struct clk_hw *hw, int degrees)
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_sclk_ws_inv_data *tph = meson_sclk_ws_inv_data(clk);
unsigned int val;
val = meson_clk_degrees_to_val(degrees, tph->ph.width);
meson_parm_write(clk->map, &tph->ph, val);
meson_parm_write(clk->map, &tph->ws, val ? 0 : 1);
return 0;
}
const struct clk_ops meson_sclk_ws_inv_ops = {
.init = meson_sclk_ws_inv_sync,
.get_phase = meson_sclk_ws_inv_get_phase,
.set_phase = meson_sclk_ws_inv_set_phase,
};
EXPORT_SYMBOL_NS_GPL(meson_sclk_ws_inv_ops, CLK_MESON);
MODULE_DESCRIPTION("Amlogic phase driver");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(CLK_MESON);