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Release 4.17 drivers/gpu/drm/sun4i/sun8i_hdmi_phy_clk.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2018 Jernej Skrabec <jernej.skrabec@siol.net>
 */

#include <linux/clk-provider.h>

#include "sun8i_dw_hdmi.h"


struct sun8i_phy_clk {
	
struct clk_hw		hw;
	
struct sun8i_hdmi_phy	*phy;
};


static inline struct sun8i_phy_clk *hw_to_phy_clk(struct clk_hw *hw) { return container_of(hw, struct sun8i_phy_clk, hw); }

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Jernej Škrabec25100.00%1100.00%
Total25100.00%1100.00%


static int sun8i_phy_clk_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { unsigned long rate = req->rate; unsigned long best_rate = 0; struct clk_hw *parent; int best_div = 1; int i; parent = clk_hw_get_parent(hw); for (i = 1; i <= 16; i++) { unsigned long ideal = rate * i; unsigned long rounded; rounded = clk_hw_round_rate(parent, ideal); if (rounded == ideal) { best_rate = rounded; best_div = i; break; } if (!best_rate || abs(rate - rounded / i) < abs(rate - best_rate / best_div)) { best_rate = rounded; best_div = i; } } req->rate = best_rate / best_div; req->best_parent_rate = best_rate; req->best_parent_hw = parent; return 0; }

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Jernej Škrabec159100.00%1100.00%
Total159100.00%1100.00%


static unsigned long sun8i_phy_clk_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct sun8i_phy_clk *priv = hw_to_phy_clk(hw); u32 reg; regmap_read(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG2_REG, &reg); reg = ((reg >> SUN8I_HDMI_PHY_PLL_CFG2_PREDIV_SHIFT) & SUN8I_HDMI_PHY_PLL_CFG2_PREDIV_MSK) + 1; return parent_rate / reg; }

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Jernej Škrabec62100.00%1100.00%
Total62100.00%1100.00%


static int sun8i_phy_clk_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { struct sun8i_phy_clk *priv = hw_to_phy_clk(hw); unsigned long best_rate = 0; u8 best_m = 0, m; for (m = 1; m <= 16; m++) { unsigned long tmp_rate = parent_rate / m; if (tmp_rate > rate) continue; if (!best_rate || (rate - tmp_rate) < (rate - best_rate)) { best_rate = tmp_rate; best_m = m; } } regmap_update_bits(priv->phy->regs, SUN8I_HDMI_PHY_PLL_CFG2_REG, SUN8I_HDMI_PHY_PLL_CFG2_PREDIV_MSK, SUN8I_HDMI_PHY_PLL_CFG2_PREDIV(best_m)); return 0; }

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Jernej Škrabec120100.00%1100.00%
Total120100.00%1100.00%

static const struct clk_ops sun8i_phy_clk_ops = { .determine_rate = sun8i_phy_clk_determine_rate, .recalc_rate = sun8i_phy_clk_recalc_rate, .set_rate = sun8i_phy_clk_set_rate, };
int sun8i_phy_clk_create(struct sun8i_hdmi_phy *phy, struct device *dev) { struct clk_init_data init; struct sun8i_phy_clk *priv; const char *parents[1]; parents[0] = __clk_get_name(phy->clk_pll0); if (!parents[0]) return -ENODEV; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; init.name = "hdmi-phy-clk"; init.ops = &sun8i_phy_clk_ops; init.parent_names = parents; init.num_parents = 1; init.flags = CLK_SET_RATE_PARENT; priv->phy = phy; priv->hw.init = &init; phy->clk_phy = devm_clk_register(dev, &priv->hw); if (IS_ERR(phy->clk_phy)) return PTR_ERR(phy->clk_phy); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jernej Škrabec160100.00%1100.00%
Total160100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Jernej Škrabec571100.00%1100.00%
Total571100.00%1100.00%
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