Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright (C) 2016 Free Electrons
 * Copyright (C) 2016 NextThing Co
 *
 * Maxime Ripard <maxime.ripard@free-electrons.com>
 */
 
#include <linux/clk-provider.h>
#include <linux/regmap.h>
 
#include "sun4i_hdmi.h"
 
struct sun4i_ddc {
<------>struct clk_hw		hw;
<------>struct sun4i_hdmi	*hdmi;
<------>struct regmap_field	*reg;
<------>u8			pre_div;
<------>u8			m_offset;
};
 
static inline struct sun4i_ddc *hw_to_ddc(struct clk_hw *hw)
{
<------>return container_of(hw, struct sun4i_ddc, hw);
}
 
static unsigned long sun4i_ddc_calc_divider(unsigned long rate,
<------><------><------><------><------>    unsigned long parent_rate,
<------><------><------><------><------>    const u8 pre_div,
<------><------><------><------><------>    const u8 m_offset,
<------><------><------><------><------>    u8 *m, u8 *n)
{
<------>unsigned long best_rate = 0;
<------>u8 best_m = 0, best_n = 0, _m, _n;
 
<------>for (_m = 0; _m < 16; _m++) {
<------><------>for (_n = 0; _n < 8; _n++) {
<------><------><------>unsigned long tmp_rate;
 
<------><------><------>tmp_rate = (((parent_rate / pre_div) / 10) >> _n) /
<------><------><------><------>(_m + m_offset);
 
<------><------><------>if (tmp_rate > rate)
<------><------><------><------>continue;
 
<------><------><------>if (abs(rate - tmp_rate) < abs(rate - best_rate)) {
<------><------><------><------>best_rate = tmp_rate;
<------><------><------><------>best_m = _m;
<------><------><------><------>best_n = _n;
<------><------><------>}
<------><------>}
<------>}
 
<------>if (m && n) {
<------><------>*m = best_m;
<------><------>*n = best_n;
<------>}
 
<------>return best_rate;
}
 
static long sun4i_ddc_round_rate(struct clk_hw *hw, unsigned long rate,
<------><------><------><------> unsigned long *prate)
{
<------>struct sun4i_ddc *ddc = hw_to_ddc(hw);
 
<------>return sun4i_ddc_calc_divider(rate, *prate, ddc->pre_div,
<------><------><------><------>      ddc->m_offset, NULL, NULL);
}
 
static unsigned long sun4i_ddc_recalc_rate(struct clk_hw *hw,
<------><------><------><------><------>    unsigned long parent_rate)
{
<------>struct sun4i_ddc *ddc = hw_to_ddc(hw);
<------>unsigned int reg;
<------>u8 m, n;
 
<------>regmap_field_read(ddc->reg, &reg);
<------>m = (reg >> 3) & 0xf;
<------>n = reg & 0x7;
 
<------>return (((parent_rate / ddc->pre_div) / 10) >> n) /
<------>       (m + ddc->m_offset);
}
 
static int sun4i_ddc_set_rate(struct clk_hw *hw, unsigned long rate,
<------><------><------>      unsigned long parent_rate)
{
<------>struct sun4i_ddc *ddc = hw_to_ddc(hw);
<------>u8 div_m, div_n;
 
<------>sun4i_ddc_calc_divider(rate, parent_rate, ddc->pre_div,
<------><------><------>       ddc->m_offset, &div_m, &div_n);
 
<------>regmap_field_write(ddc->reg,
<------><------><------>   SUN4I_HDMI_DDC_CLK_M(div_m) |
<------><------><------>   SUN4I_HDMI_DDC_CLK_N(div_n));
 
<------>return 0;
}
 
static const struct clk_ops sun4i_ddc_ops = {
<------>.recalc_rate	= sun4i_ddc_recalc_rate,
<------>.round_rate	= sun4i_ddc_round_rate,
<------>.set_rate	= sun4i_ddc_set_rate,
};
 
int sun4i_ddc_create(struct sun4i_hdmi *hdmi, struct clk *parent)
{
<------>struct clk_init_data init;
<------>struct sun4i_ddc *ddc;
<------>const char *parent_name;
 
<------>parent_name = __clk_get_name(parent);
<------>if (!parent_name)
<------><------>return -ENODEV;
 
<------>ddc = devm_kzalloc(hdmi->dev, sizeof(*ddc), GFP_KERNEL);
<------>if (!ddc)
<------><------>return -ENOMEM;
 
<------>ddc->reg = devm_regmap_field_alloc(hdmi->dev, hdmi->regmap,
<------><------><------><------><------>   hdmi->variant->ddc_clk_reg);
<------>if (IS_ERR(ddc->reg))
<------><------>return PTR_ERR(ddc->reg);
 
<------>init.name = "hdmi-ddc";
<------>init.ops = &sun4i_ddc_ops;
<------>init.parent_names = &parent_name;
<------>init.num_parents = 1;
 
<------>ddc->hdmi = hdmi;
<------>ddc->hw.init = &init;
<------>ddc->pre_div = hdmi->variant->ddc_clk_pre_divider;
<------>ddc->m_offset = hdmi->variant->ddc_clk_m_offset;
 
<------>hdmi->ddc_clk = devm_clk_register(hdmi->dev, &ddc->hw);
<------>if (IS_ERR(hdmi->ddc_clk))
<------><------>return PTR_ERR(hdmi->ddc_clk);
 
<------>return 0;
}