drivers/clk/clk-cs2000-cp.c - third_party/kernel - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * CS2000  --  CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
  *
  * Copyright (C) 2015 Renesas Electronics Corporation
  * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
  */
 #include <linux/clk-provider.h>
 #include <linux/delay.h>
 #include <linux/clk.h>
 #include <linux/i2c.h>
 #include <linux/of_device.h>
 #include <linux/module.h>
 #include <linux/regmap.h>

 #define CH_MAX 4
 #define RATIO_REG_SIZE 4

 #define DEVICE_ID	0x1
 #define DEVICE_CTRL	0x2
 #define DEVICE_CFG1	0x3
 #define DEVICE_CFG2	0x4
 #define GLOBAL_CFG	0x5
 #define Ratio_Add(x, nth)	(6 + (x * 4) + (nth))
 #define Ratio_Val(x, nth)	((x >> (24 - (8 * nth))) & 0xFF)
 #define Val_Ratio(x, nth)	((x & 0xFF) << (24 - (8 * nth)))
 #define FUNC_CFG1	0x16
 #define FUNC_CFG2	0x17

 /* DEVICE_ID */
 #define REVISION_MASK	(0x7)
 #define REVISION_B2_B3	(0x4)
 #define REVISION_C1	(0x6)

 /* DEVICE_CTRL */
 #define PLL_UNLOCK	(1 << 7)
 #define AUXOUTDIS	(1 << 1)
 #define CLKOUTDIS	(1 << 0)

 /* DEVICE_CFG1 */
 #define RSEL(x)		(((x) & 0x3) << 3)
 #define RSEL_MASK	RSEL(0x3)
 #define AUXOUTSRC(x)	(((x) & 0x3) << 1)
 #define AUXOUTSRC_MASK	AUXOUTSRC(0x3)
 #define ENDEV1		(0x1)

 /* DEVICE_CFG2 */
 #define AUTORMOD	(1 << 3)
 #define LOCKCLK(x)	(((x) & 0x3) << 1)
 #define LOCKCLK_MASK	LOCKCLK(0x3)
 #define FRACNSRC_MASK	(1 << 0)
 #define FRACNSRC_STATIC		(0 << 0)
 #define FRACNSRC_DYNAMIC	(1 << 0)

 /* GLOBAL_CFG */
 #define FREEZE		(1 << 7)
 #define ENDEV2		(0x1)

 /* FUNC_CFG1 */
 #define CLKSKIPEN	(1 << 7)
 #define REFCLKDIV(x)	(((x) & 0x3) << 3)
 #define REFCLKDIV_MASK	REFCLKDIV(0x3)

 /* FUNC_CFG2 */
 #define LFRATIO_MASK	(1 << 3)
 #define LFRATIO_20_12	(0 << 3)
 #define LFRATIO_12_20	(1 << 3)

 #define CH_SIZE_ERR(ch)		((ch < 0) || (ch >= CH_MAX))
 #define hw_to_priv(_hw)		container_of(_hw, struct cs2000_priv, hw)
 #define priv_to_client(priv)	(priv->client)
 #define priv_to_dev(priv)	(&(priv_to_client(priv)->dev))

 #define CLK_IN	0
 #define REF_CLK	1
 #define CLK_MAX 2

 static bool cs2000_readable_reg(struct device *dev, unsigned int reg)
 {
 	return reg > 0;
 }

 static bool cs2000_writeable_reg(struct device *dev, unsigned int reg)
 {
 	return reg != DEVICE_ID;
 }

 static bool cs2000_volatile_reg(struct device *dev, unsigned int reg)
 {
 	return reg == DEVICE_CTRL;
 }

 static const struct regmap_config cs2000_regmap_config = {
 	.reg_bits	= 8,
 	.val_bits	= 8,
 	.max_register	= FUNC_CFG2,
 	.readable_reg	= cs2000_readable_reg,
 	.writeable_reg	= cs2000_writeable_reg,
 	.volatile_reg	= cs2000_volatile_reg,
 };

 struct cs2000_priv {
 	struct clk_hw hw;
 	struct i2c_client *client;
 	struct clk *clk_in;
 	struct clk *ref_clk;
 	struct regmap *regmap;

 	bool dynamic_mode;
 	bool lf_ratio;
 	bool clk_skip;

 	/* suspend/resume */
 	unsigned long saved_rate;
 	unsigned long saved_parent_rate;
 };

 static const struct of_device_id cs2000_of_match[] = {
 	{ .compatible = "cirrus,cs2000-cp", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, cs2000_of_match);

 static const struct i2c_device_id cs2000_id[] = {
 	{ "cs2000-cp", },
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, cs2000_id);

 static int cs2000_enable_dev_config(struct cs2000_priv *priv, bool enable)
 {
 	int ret;

 	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1, ENDEV1,
 				 enable ? ENDEV1 : 0);
 	if (ret < 0)
 		return ret;

 	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG,  ENDEV2,
 				 enable ? ENDEV2 : 0);
 	if (ret < 0)
 		return ret;

 	ret = regmap_update_bits(priv->regmap, FUNC_CFG1, CLKSKIPEN,
 				 (enable && priv->clk_skip) ? CLKSKIPEN : 0);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int cs2000_ref_clk_bound_rate(struct cs2000_priv *priv,
 				     u32 rate_in)
 {
 	u32 val;

 	if (rate_in >= 32000000 && rate_in < 56000000)
 		val = 0x0;
 	else if (rate_in >= 16000000 && rate_in < 28000000)
 		val = 0x1;
 	else if (rate_in >= 8000000 && rate_in < 14000000)
 		val = 0x2;
 	else
 		return -EINVAL;

 	return regmap_update_bits(priv->regmap, FUNC_CFG1,
 				  REFCLKDIV_MASK,
 				  REFCLKDIV(val));
 }

 static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
 {
 	struct device *dev = priv_to_dev(priv);
 	unsigned int i, val;
 	int ret;

 	for (i = 0; i < 256; i++) {
 		ret = regmap_read(priv->regmap, DEVICE_CTRL, &val);
 		if (ret < 0)
 			return ret;
 		if (!(val & PLL_UNLOCK))
 			return 0;
 		udelay(1);
 	}

 	dev_err(dev, "pll lock failed\n");

 	return -ETIMEDOUT;
 }

 static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable)
 {
 	/* enable both AUX_OUT, CLK_OUT */
 	return regmap_update_bits(priv->regmap, DEVICE_CTRL,
 				  (AUXOUTDIS | CLKOUTDIS),
 				  enable ? 0 :
 				  (AUXOUTDIS | CLKOUTDIS));
 }

 static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out, bool lf_ratio)
 {
 	u64 ratio;
 	u32 multiplier = lf_ratio ? 12 : 20;

 	/*
 	 * ratio = rate_out / rate_in * 2^multiplier
 	 *
 	 * To avoid over flow, rate_out is u64.
 	 * The result should be u32.
 	 */
 	ratio = (u64)rate_out << multiplier;
 	do_div(ratio, rate_in);

 	return ratio;
 }

 static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in, bool lf_ratio)
 {
 	u64 rate_out;
 	u32 multiplier = lf_ratio ? 12 : 20;

 	/*
 	 * ratio = rate_out / rate_in * 2^multiplier
 	 *
 	 * To avoid over flow, rate_out is u64.
 	 * The result should be u32 or unsigned long.
 	 */

 	rate_out = (u64)ratio * rate_in;
 	return rate_out >> multiplier;
 }

 static int cs2000_ratio_set(struct cs2000_priv *priv,
 			    int ch, u32 rate_in, u32 rate_out)
 {
 	u32 val;
 	unsigned int i;
 	int ret;

 	if (CH_SIZE_ERR(ch))
 		return -EINVAL;

 	val = cs2000_rate_to_ratio(rate_in, rate_out, priv->lf_ratio);
 	for (i = 0; i < RATIO_REG_SIZE; i++) {
 		ret = regmap_write(priv->regmap,
 				   Ratio_Add(ch, i),
 				   Ratio_Val(val, i));
 		if (ret < 0)
 			return ret;
 	}

 	return 0;
 }

 static u32 cs2000_ratio_get(struct cs2000_priv *priv, int ch)
 {
 	unsigned int tmp, i;
 	u32 val;
 	int ret;

 	val = 0;
 	for (i = 0; i < RATIO_REG_SIZE; i++) {
 		ret = regmap_read(priv->regmap, Ratio_Add(ch, i), &tmp);
 		if (ret < 0)
 			return 0;

 		val |= Val_Ratio(tmp, i);
 	}

 	return val;
 }

 static int cs2000_ratio_select(struct cs2000_priv *priv, int ch)
 {
 	int ret;
 	u8 fracnsrc;

 	if (CH_SIZE_ERR(ch))
 		return -EINVAL;

 	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
 	if (ret < 0)
 		return ret;

 	fracnsrc = priv->dynamic_mode ? FRACNSRC_DYNAMIC : FRACNSRC_STATIC;

 	ret = regmap_update_bits(priv->regmap, DEVICE_CFG2,
 				 AUTORMOD | LOCKCLK_MASK | FRACNSRC_MASK,
 				 LOCKCLK(ch) | fracnsrc);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static unsigned long cs2000_recalc_rate(struct clk_hw *hw,
 					unsigned long parent_rate)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);
 	int ch = 0; /* it uses ch0 only at this point */
 	u32 ratio;

 	ratio = cs2000_ratio_get(priv, ch);

 	return cs2000_ratio_to_rate(ratio, parent_rate, priv->lf_ratio);
 }

 static long cs2000_round_rate(struct clk_hw *hw, unsigned long rate,
 			      unsigned long *parent_rate)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);
 	u32 ratio;

 	ratio = cs2000_rate_to_ratio(*parent_rate, rate, priv->lf_ratio);

 	return cs2000_ratio_to_rate(ratio, *parent_rate, priv->lf_ratio);
 }

 static int cs2000_select_ratio_mode(struct cs2000_priv *priv,
 				    unsigned long rate,
 				    unsigned long parent_rate)
 {
 	/*
 	 * From the datasheet:
 	 *
 	 * | It is recommended that the 12.20 High-Resolution format be
 	 * | utilized whenever the desired ratio is less than 4096 since
 	 * | the output frequency accuracy of the PLL is directly proportional
 	 * | to the accuracy of the timing reference clock and the resolution
 	 * | of the R_UD.
 	 *
 	 * This mode is only available in dynamic mode.
 	 */
 	priv->lf_ratio = priv->dynamic_mode && ((rate / parent_rate) > 4096);

 	return regmap_update_bits(priv->regmap, FUNC_CFG2, LFRATIO_MASK,
 				  priv->lf_ratio ? LFRATIO_20_12 : LFRATIO_12_20);
 }

 static int __cs2000_set_rate(struct cs2000_priv *priv, int ch,
 			     unsigned long rate, unsigned long parent_rate)

 {
 	int ret;

 	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG, FREEZE, FREEZE);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_select_ratio_mode(priv, rate, parent_rate);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_ratio_set(priv, ch, parent_rate, rate);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_ratio_select(priv, ch);
 	if (ret < 0)
 		return ret;

 	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG, FREEZE, 0);
 	if (ret < 0)
 		return ret;

 	priv->saved_rate	= rate;
 	priv->saved_parent_rate	= parent_rate;

 	return 0;
 }

 static int cs2000_set_rate(struct clk_hw *hw,
 			   unsigned long rate, unsigned long parent_rate)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);
 	int ch = 0; /* it uses ch0 only at this point */

 	return __cs2000_set_rate(priv, ch, rate, parent_rate);
 }

 static int cs2000_set_saved_rate(struct cs2000_priv *priv)
 {
 	int ch = 0; /* it uses ch0 only at this point */

 	return __cs2000_set_rate(priv, ch,
 				 priv->saved_rate,
 				 priv->saved_parent_rate);
 }

 static int cs2000_enable(struct clk_hw *hw)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);
 	int ret;

 	ret = cs2000_enable_dev_config(priv, true);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_clk_out_enable(priv, true);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_wait_pll_lock(priv);
 	if (ret < 0)
 		return ret;

 	return ret;
 }

 static void cs2000_disable(struct clk_hw *hw)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);

 	cs2000_enable_dev_config(priv, false);

 	cs2000_clk_out_enable(priv, false);
 }

 static u8 cs2000_get_parent(struct clk_hw *hw)
 {
 	struct cs2000_priv *priv = hw_to_priv(hw);

 	/*
 	 * In dynamic mode, output rates are derived from CLK_IN.
 	 * In static mode, CLK_IN is ignored, so we return REF_CLK instead.
 	 */
 	return priv->dynamic_mode ? CLK_IN : REF_CLK;
 }

 static const struct clk_ops cs2000_ops = {
 	.get_parent	= cs2000_get_parent,
 	.recalc_rate	= cs2000_recalc_rate,
 	.round_rate	= cs2000_round_rate,
 	.set_rate	= cs2000_set_rate,
 	.prepare	= cs2000_enable,
 	.unprepare	= cs2000_disable,
 };

 static int cs2000_clk_get(struct cs2000_priv *priv)
 {
 	struct device *dev = priv_to_dev(priv);
 	struct clk *clk_in, *ref_clk;

 	clk_in = devm_clk_get(dev, "clk_in");
 	/* not yet provided */
 	if (IS_ERR(clk_in))
 		return -EPROBE_DEFER;

 	ref_clk = devm_clk_get(dev, "ref_clk");
 	/* not yet provided */
 	if (IS_ERR(ref_clk))
 		return -EPROBE_DEFER;

 	priv->clk_in	= clk_in;
 	priv->ref_clk	= ref_clk;

 	return 0;
 }

 static int cs2000_clk_register(struct cs2000_priv *priv)
 {
 	struct device *dev = priv_to_dev(priv);
 	struct device_node *np = dev->of_node;
 	struct clk_init_data init;
 	const char *name = np->name;
 	static const char *parent_names[CLK_MAX];
 	u32 aux_out = 0;
 	int ref_clk_rate;
 	int ch = 0; /* it uses ch0 only at this point */
 	int ret;

 	of_property_read_string(np, "clock-output-names", &name);

 	priv->dynamic_mode = of_property_read_bool(np, "cirrus,dynamic-mode");
 	dev_info(dev, "operating in %s mode\n",
 		 priv->dynamic_mode ? "dynamic" : "static");

 	of_property_read_u32(np, "cirrus,aux-output-source", &aux_out);
 	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1,
 				 AUXOUTSRC_MASK, AUXOUTSRC(aux_out));
 	if (ret < 0)
 		return ret;

 	priv->clk_skip = of_property_read_bool(np, "cirrus,clock-skip");

 	ref_clk_rate = clk_get_rate(priv->ref_clk);
 	ret = cs2000_ref_clk_bound_rate(priv, ref_clk_rate);
 	if (ret < 0)
 		return ret;

 	if (priv->dynamic_mode) {
 		/* Default to low-frequency mode to allow for large ratios */
 		priv->lf_ratio = true;
 	} else {
 		/*
 		 * set default rate as 1/1.
 		 * otherwise .set_rate which setup ratio
 		 * is never called if user requests 1/1 rate
 		 */
 		ret = __cs2000_set_rate(priv, ch, ref_clk_rate, ref_clk_rate);
 		if (ret < 0)
 			return ret;
 	}

 	parent_names[CLK_IN]	= __clk_get_name(priv->clk_in);
 	parent_names[REF_CLK]	= __clk_get_name(priv->ref_clk);

 	init.name		= name;
 	init.ops		= &cs2000_ops;
 	init.flags		= CLK_SET_RATE_GATE;
 	init.parent_names	= parent_names;
 	init.num_parents	= ARRAY_SIZE(parent_names);

 	priv->hw.init = &init;

 	ret = clk_hw_register(dev, &priv->hw);
 	if (ret)
 		return ret;

 	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
 	if (ret < 0) {
 		clk_hw_unregister(&priv->hw);
 		return ret;
 	}

 	return 0;
 }

 static int cs2000_version_print(struct cs2000_priv *priv)
 {
 	struct device *dev = priv_to_dev(priv);
 	const char *revision;
 	unsigned int val;
 	int ret;

 	ret = regmap_read(priv->regmap, DEVICE_ID, &val);
 	if (ret < 0)
 		return ret;

 	/* CS2000 should be 0x0 */
 	if (val >> 3)
 		return -EIO;

 	switch (val & REVISION_MASK) {
 	case REVISION_B2_B3:
 		revision = "B2 / B3";
 		break;
 	case REVISION_C1:
 		revision = "C1";
 		break;
 	default:
 		return -EIO;
 	}

 	dev_info(dev, "revision - %s\n", revision);

 	return 0;
 }

 static void cs2000_remove(struct i2c_client *client)
 {
 	struct cs2000_priv *priv = i2c_get_clientdata(client);
 	struct device *dev = priv_to_dev(priv);
 	struct device_node *np = dev->of_node;

 	of_clk_del_provider(np);

 	clk_hw_unregister(&priv->hw);
 }

 static int cs2000_probe(struct i2c_client *client)
 {
 	struct cs2000_priv *priv;
 	struct device *dev = &client->dev;
 	int ret;

 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	priv->client = client;
 	i2c_set_clientdata(client, priv);

 	priv->regmap = devm_regmap_init_i2c(client, &cs2000_regmap_config);
 	if (IS_ERR(priv->regmap))
 		return PTR_ERR(priv->regmap);

 	ret = cs2000_clk_get(priv);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_clk_register(priv);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_version_print(priv);
 	if (ret < 0)
 		goto probe_err;

 	return 0;

 probe_err:
 	cs2000_remove(client);

 	return ret;
 }

 static int __maybe_unused cs2000_resume(struct device *dev)
 {
 	struct cs2000_priv *priv = dev_get_drvdata(dev);

 	return cs2000_set_saved_rate(priv);
 }

 static const struct dev_pm_ops cs2000_pm_ops = {
 	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, cs2000_resume)
 };

 static struct i2c_driver cs2000_driver = {
 	.driver = {
 		.name = "cs2000-cp",
 		.pm	= &cs2000_pm_ops,
 		.of_match_table = cs2000_of_match,
 	},
 	.probe_new	= cs2000_probe,
 	.remove		= cs2000_remove,
 	.id_table	= cs2000_id,
 };

 module_i2c_driver(cs2000_driver);

 MODULE_DESCRIPTION("CS2000-CP driver");
 MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
	*
	* Copyright (C) 2015 Renesas Electronics Corporation
	* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
	*/
	#include <linux/clk-provider.h>
	#include <linux/delay.h>
	#include <linux/clk.h>
	#include <linux/i2c.h>
	#include <linux/of_device.h>
	#include <linux/module.h>
	#include <linux/regmap.h>

	#define CH_MAX 4
	#define RATIO_REG_SIZE 4

	#define DEVICE_ID 0x1
	#define DEVICE_CTRL 0x2
	#define DEVICE_CFG1 0x3
	#define DEVICE_CFG2 0x4
	#define GLOBAL_CFG 0x5
	#define Ratio_Add(x, nth) (6 + (x * 4) + (nth))
	#define Ratio_Val(x, nth) ((x >> (24 - (8 * nth))) & 0xFF)
	#define Val_Ratio(x, nth) ((x & 0xFF) << (24 - (8 * nth)))
	#define FUNC_CFG1 0x16
	#define FUNC_CFG2 0x17

	/* DEVICE_ID */
	#define REVISION_MASK (0x7)
	#define REVISION_B2_B3 (0x4)
	#define REVISION_C1 (0x6)

	/* DEVICE_CTRL */
	#define PLL_UNLOCK (1 << 7)
	#define AUXOUTDIS (1 << 1)
	#define CLKOUTDIS (1 << 0)

	/* DEVICE_CFG1 */
	#define RSEL(x) (((x) & 0x3) << 3)
	#define RSEL_MASK RSEL(0x3)
	#define AUXOUTSRC(x) (((x) & 0x3) << 1)
	#define AUXOUTSRC_MASK AUXOUTSRC(0x3)
	#define ENDEV1 (0x1)

	/* DEVICE_CFG2 */
	#define AUTORMOD (1 << 3)
	#define LOCKCLK(x) (((x) & 0x3) << 1)
	#define LOCKCLK_MASK LOCKCLK(0x3)
	#define FRACNSRC_MASK (1 << 0)
	#define FRACNSRC_STATIC (0 << 0)
	#define FRACNSRC_DYNAMIC (1 << 0)

	/* GLOBAL_CFG */
	#define FREEZE (1 << 7)
	#define ENDEV2 (0x1)

	/* FUNC_CFG1 */
	#define CLKSKIPEN (1 << 7)
	#define REFCLKDIV(x) (((x) & 0x3) << 3)
	#define REFCLKDIV_MASK REFCLKDIV(0x3)

	/* FUNC_CFG2 */
	#define LFRATIO_MASK (1 << 3)
	#define LFRATIO_20_12 (0 << 3)
	#define LFRATIO_12_20 (1 << 3)

	#define CH_SIZE_ERR(ch) ((ch < 0) \|\| (ch >= CH_MAX))
	#define hw_to_priv(_hw) container_of(_hw, struct cs2000_priv, hw)
	#define priv_to_client(priv) (priv->client)
	#define priv_to_dev(priv) (&(priv_to_client(priv)->dev))

	#define CLK_IN 0
	#define REF_CLK 1
	#define CLK_MAX 2

	static bool cs2000_readable_reg(struct device *dev, unsigned int reg)
	{
	return reg > 0;
	}

	static bool cs2000_writeable_reg(struct device *dev, unsigned int reg)
	{
	return reg != DEVICE_ID;
	}

	static bool cs2000_volatile_reg(struct device *dev, unsigned int reg)
	{
	return reg == DEVICE_CTRL;
	}

	static const struct regmap_config cs2000_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = FUNC_CFG2,
	.readable_reg = cs2000_readable_reg,
	.writeable_reg = cs2000_writeable_reg,
	.volatile_reg = cs2000_volatile_reg,
	};

	struct cs2000_priv {
	struct clk_hw hw;
	struct i2c_client *client;
	struct clk *clk_in;
	struct clk *ref_clk;
	struct regmap *regmap;

	bool dynamic_mode;
	bool lf_ratio;
	bool clk_skip;

	/* suspend/resume */
	unsigned long saved_rate;
	unsigned long saved_parent_rate;
	};

	static const struct of_device_id cs2000_of_match[] = {
	{ .compatible = "cirrus,cs2000-cp", },
	{},
	};
	MODULE_DEVICE_TABLE(of, cs2000_of_match);

	static const struct i2c_device_id cs2000_id[] = {
	{ "cs2000-cp", },
	{}
	};
	MODULE_DEVICE_TABLE(i2c, cs2000_id);

	static int cs2000_enable_dev_config(struct cs2000_priv *priv, bool enable)
	{
	int ret;

	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1, ENDEV1,
	enable ? ENDEV1 : 0);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG, ENDEV2,
	enable ? ENDEV2 : 0);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(priv->regmap, FUNC_CFG1, CLKSKIPEN,
	(enable && priv->clk_skip) ? CLKSKIPEN : 0);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int cs2000_ref_clk_bound_rate(struct cs2000_priv *priv,
	u32 rate_in)
	{
	u32 val;

	if (rate_in >= 32000000 && rate_in < 56000000)
	val = 0x0;
	else if (rate_in >= 16000000 && rate_in < 28000000)
	val = 0x1;
	else if (rate_in >= 8000000 && rate_in < 14000000)
	val = 0x2;
	else
	return -EINVAL;

	return regmap_update_bits(priv->regmap, FUNC_CFG1,
	REFCLKDIV_MASK,
	REFCLKDIV(val));
	}

	static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
	{
	struct device *dev = priv_to_dev(priv);
	unsigned int i, val;
	int ret;

	for (i = 0; i < 256; i++) {
	ret = regmap_read(priv->regmap, DEVICE_CTRL, &val);
	if (ret < 0)
	return ret;
	if (!(val & PLL_UNLOCK))
	return 0;
	udelay(1);
	}

	dev_err(dev, "pll lock failed\n");

	return -ETIMEDOUT;
	}

	static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable)
	{
	/* enable both AUX_OUT, CLK_OUT */
	return regmap_update_bits(priv->regmap, DEVICE_CTRL,
	(AUXOUTDIS \| CLKOUTDIS),
	enable ? 0 :
	(AUXOUTDIS \| CLKOUTDIS));
	}

	static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out, bool lf_ratio)
	{
	u64 ratio;
	u32 multiplier = lf_ratio ? 12 : 20;

	/*
	* ratio = rate_out / rate_in * 2^multiplier
	*
	* To avoid over flow, rate_out is u64.
	* The result should be u32.
	*/
	ratio = (u64)rate_out << multiplier;
	do_div(ratio, rate_in);

	return ratio;
	}

	static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in, bool lf_ratio)
	{
	u64 rate_out;
	u32 multiplier = lf_ratio ? 12 : 20;

	/*
	* ratio = rate_out / rate_in * 2^multiplier
	*
	* To avoid over flow, rate_out is u64.
	* The result should be u32 or unsigned long.
	*/

	rate_out = (u64)ratio * rate_in;
	return rate_out >> multiplier;
	}

	static int cs2000_ratio_set(struct cs2000_priv *priv,
	int ch, u32 rate_in, u32 rate_out)
	{
	u32 val;
	unsigned int i;
	int ret;

	if (CH_SIZE_ERR(ch))
	return -EINVAL;

	val = cs2000_rate_to_ratio(rate_in, rate_out, priv->lf_ratio);
	for (i = 0; i < RATIO_REG_SIZE; i++) {
	ret = regmap_write(priv->regmap,
	Ratio_Add(ch, i),
	Ratio_Val(val, i));
	if (ret < 0)
	return ret;
	}

	return 0;
	}

	static u32 cs2000_ratio_get(struct cs2000_priv *priv, int ch)
	{
	unsigned int tmp, i;
	u32 val;
	int ret;

	val = 0;
	for (i = 0; i < RATIO_REG_SIZE; i++) {
	ret = regmap_read(priv->regmap, Ratio_Add(ch, i), &tmp);
	if (ret < 0)
	return 0;

	val \|= Val_Ratio(tmp, i);
	}

	return val;
	}

	static int cs2000_ratio_select(struct cs2000_priv *priv, int ch)
	{
	int ret;
	u8 fracnsrc;

	if (CH_SIZE_ERR(ch))
	return -EINVAL;

	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
	if (ret < 0)
	return ret;

	fracnsrc = priv->dynamic_mode ? FRACNSRC_DYNAMIC : FRACNSRC_STATIC;

	ret = regmap_update_bits(priv->regmap, DEVICE_CFG2,
	AUTORMOD \| LOCKCLK_MASK \| FRACNSRC_MASK,
	LOCKCLK(ch) \| fracnsrc);
	if (ret < 0)
	return ret;

	return 0;
	}

	static unsigned long cs2000_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);
	int ch = 0; /* it uses ch0 only at this point */
	u32 ratio;

	ratio = cs2000_ratio_get(priv, ch);

	return cs2000_ratio_to_rate(ratio, parent_rate, priv->lf_ratio);
	}

	static long cs2000_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *parent_rate)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);
	u32 ratio;

	ratio = cs2000_rate_to_ratio(*parent_rate, rate, priv->lf_ratio);

	return cs2000_ratio_to_rate(ratio, *parent_rate, priv->lf_ratio);
	}

	static int cs2000_select_ratio_mode(struct cs2000_priv *priv,
	unsigned long rate,
	unsigned long parent_rate)
	{
	/*
	* From the datasheet:
	*
	* \| It is recommended that the 12.20 High-Resolution format be
	* \| utilized whenever the desired ratio is less than 4096 since
	* \| the output frequency accuracy of the PLL is directly proportional
	* \| to the accuracy of the timing reference clock and the resolution
	* \| of the R_UD.
	*
	* This mode is only available in dynamic mode.
	*/
	priv->lf_ratio = priv->dynamic_mode && ((rate / parent_rate) > 4096);

	return regmap_update_bits(priv->regmap, FUNC_CFG2, LFRATIO_MASK,
	priv->lf_ratio ? LFRATIO_20_12 : LFRATIO_12_20);
	}

	static int __cs2000_set_rate(struct cs2000_priv *priv, int ch,
	unsigned long rate, unsigned long parent_rate)

	{
	int ret;

	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG, FREEZE, FREEZE);
	if (ret < 0)
	return ret;

	ret = cs2000_select_ratio_mode(priv, rate, parent_rate);
	if (ret < 0)
	return ret;

	ret = cs2000_ratio_set(priv, ch, parent_rate, rate);
	if (ret < 0)
	return ret;

	ret = cs2000_ratio_select(priv, ch);
	if (ret < 0)
	return ret;

	ret = regmap_update_bits(priv->regmap, GLOBAL_CFG, FREEZE, 0);
	if (ret < 0)
	return ret;

	priv->saved_rate = rate;
	priv->saved_parent_rate = parent_rate;

	return 0;
	}

	static int cs2000_set_rate(struct clk_hw *hw,
	unsigned long rate, unsigned long parent_rate)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);
	int ch = 0; /* it uses ch0 only at this point */

	return __cs2000_set_rate(priv, ch, rate, parent_rate);
	}

	static int cs2000_set_saved_rate(struct cs2000_priv *priv)
	{
	int ch = 0; /* it uses ch0 only at this point */

	return __cs2000_set_rate(priv, ch,
	priv->saved_rate,
	priv->saved_parent_rate);
	}

	static int cs2000_enable(struct clk_hw *hw)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);
	int ret;

	ret = cs2000_enable_dev_config(priv, true);
	if (ret < 0)
	return ret;

	ret = cs2000_clk_out_enable(priv, true);
	if (ret < 0)
	return ret;

	ret = cs2000_wait_pll_lock(priv);
	if (ret < 0)
	return ret;

	return ret;
	}

	static void cs2000_disable(struct clk_hw *hw)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);

	cs2000_enable_dev_config(priv, false);

	cs2000_clk_out_enable(priv, false);
	}

	static u8 cs2000_get_parent(struct clk_hw *hw)
	{
	struct cs2000_priv *priv = hw_to_priv(hw);

	/*
	* In dynamic mode, output rates are derived from CLK_IN.
	* In static mode, CLK_IN is ignored, so we return REF_CLK instead.
	*/
	return priv->dynamic_mode ? CLK_IN : REF_CLK;
	}

	static const struct clk_ops cs2000_ops = {
	.get_parent = cs2000_get_parent,
	.recalc_rate = cs2000_recalc_rate,
	.round_rate = cs2000_round_rate,
	.set_rate = cs2000_set_rate,
	.prepare = cs2000_enable,
	.unprepare = cs2000_disable,
	};

	static int cs2000_clk_get(struct cs2000_priv *priv)
	{
	struct device *dev = priv_to_dev(priv);
	struct clk clk_in, ref_clk;

	clk_in = devm_clk_get(dev, "clk_in");
	/* not yet provided */
	if (IS_ERR(clk_in))
	return -EPROBE_DEFER;

	ref_clk = devm_clk_get(dev, "ref_clk");
	/* not yet provided */
	if (IS_ERR(ref_clk))
	return -EPROBE_DEFER;

	priv->clk_in = clk_in;
	priv->ref_clk = ref_clk;

	return 0;
	}

	static int cs2000_clk_register(struct cs2000_priv *priv)
	{
	struct device *dev = priv_to_dev(priv);
	struct device_node *np = dev->of_node;
	struct clk_init_data init;
	const char *name = np->name;
	static const char *parent_names[CLK_MAX];
	u32 aux_out = 0;
	int ref_clk_rate;
	int ch = 0; /* it uses ch0 only at this point */
	int ret;

	of_property_read_string(np, "clock-output-names", &name);

	priv->dynamic_mode = of_property_read_bool(np, "cirrus,dynamic-mode");
	dev_info(dev, "operating in %s mode\n",
	priv->dynamic_mode ? "dynamic" : "static");

	of_property_read_u32(np, "cirrus,aux-output-source", &aux_out);
	ret = regmap_update_bits(priv->regmap, DEVICE_CFG1,
	AUXOUTSRC_MASK, AUXOUTSRC(aux_out));
	if (ret < 0)
	return ret;

	priv->clk_skip = of_property_read_bool(np, "cirrus,clock-skip");

	ref_clk_rate = clk_get_rate(priv->ref_clk);
	ret = cs2000_ref_clk_bound_rate(priv, ref_clk_rate);
	if (ret < 0)
	return ret;

	if (priv->dynamic_mode) {
	/* Default to low-frequency mode to allow for large ratios */
	priv->lf_ratio = true;
	} else {
	/*
	* set default rate as 1/1.
	* otherwise .set_rate which setup ratio
	* is never called if user requests 1/1 rate
	*/
	ret = __cs2000_set_rate(priv, ch, ref_clk_rate, ref_clk_rate);
	if (ret < 0)
	return ret;
	}

	parent_names[CLK_IN] = __clk_get_name(priv->clk_in);
	parent_names[REF_CLK] = __clk_get_name(priv->ref_clk);

	init.name = name;
	init.ops = &cs2000_ops;
	init.flags = CLK_SET_RATE_GATE;
	init.parent_names = parent_names;
	init.num_parents = ARRAY_SIZE(parent_names);

	priv->hw.init = &init;

	ret = clk_hw_register(dev, &priv->hw);
	if (ret)
	return ret;

	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
	if (ret < 0) {
	clk_hw_unregister(&priv->hw);
	return ret;
	}

	return 0;
	}

	static int cs2000_version_print(struct cs2000_priv *priv)
	{
	struct device *dev = priv_to_dev(priv);
	const char *revision;
	unsigned int val;
	int ret;

	ret = regmap_read(priv->regmap, DEVICE_ID, &val);
	if (ret < 0)
	return ret;

	/* CS2000 should be 0x0 */
	if (val >> 3)
	return -EIO;

	switch (val & REVISION_MASK) {
	case REVISION_B2_B3:
	revision = "B2 / B3";
	break;
	case REVISION_C1:
	revision = "C1";
	break;
	default:
	return -EIO;
	}

	dev_info(dev, "revision - %s\n", revision);

	return 0;
	}

	static void cs2000_remove(struct i2c_client *client)
	{
	struct cs2000_priv *priv = i2c_get_clientdata(client);
	struct device *dev = priv_to_dev(priv);
	struct device_node *np = dev->of_node;

	of_clk_del_provider(np);

	clk_hw_unregister(&priv->hw);
	}

	static int cs2000_probe(struct i2c_client *client)
	{
	struct cs2000_priv *priv;
	struct device *dev = &client->dev;
	int ret;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	priv->client = client;
	i2c_set_clientdata(client, priv);

	priv->regmap = devm_regmap_init_i2c(client, &cs2000_regmap_config);
	if (IS_ERR(priv->regmap))
	return PTR_ERR(priv->regmap);

	ret = cs2000_clk_get(priv);
	if (ret < 0)
	return ret;

	ret = cs2000_clk_register(priv);
	if (ret < 0)
	return ret;

	ret = cs2000_version_print(priv);
	if (ret < 0)
	goto probe_err;

	return 0;

	probe_err:
	cs2000_remove(client);

	return ret;
	}

	static int __maybe_unused cs2000_resume(struct device *dev)
	{
	struct cs2000_priv *priv = dev_get_drvdata(dev);

	return cs2000_set_saved_rate(priv);
	}

	static const struct dev_pm_ops cs2000_pm_ops = {
	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, cs2000_resume)
	};

	static struct i2c_driver cs2000_driver = {
	.driver = {
	.name = "cs2000-cp",
	.pm = &cs2000_pm_ops,
	.of_match_table = cs2000_of_match,
	},
	.probe_new = cs2000_probe,
	.remove = cs2000_remove,
	.id_table = cs2000_id,
	};

	module_i2c_driver(cs2000_driver);

	MODULE_DESCRIPTION("CS2000-CP driver");
	MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
	MODULE_LICENSE("GPL v2");