drivers/clk/clk-cs2000-cp.c - kernel/msm-4.19 - Gitiles

 /*
  * CS2000  --  CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
  *
  * Copyright (C) 2015 Renesas Electronics Corporation
  * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
 #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>

 #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 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 << 1)

 /* GLOBAL_CFG */
 #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

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

 	/* 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);

 #define cs2000_read(priv, addr) \
 	i2c_smbus_read_byte_data(priv_to_client(priv), addr)
 #define cs2000_write(priv, addr, val) \
 	i2c_smbus_write_byte_data(priv_to_client(priv), addr, val)

 static int cs2000_bset(struct cs2000_priv *priv, u8 addr, u8 mask, u8 val)
 {
 	s32 data;

 	data = cs2000_read(priv, addr);
 	if (data < 0)
 		return data;

 	data &= ~mask;
 	data |= (val & mask);

 	return cs2000_write(priv, addr, data);
 }

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

 	ret = cs2000_bset(priv, DEVICE_CFG1, ENDEV1,
 			  enable ? ENDEV1 : 0);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_bset(priv, GLOBAL_CFG,  ENDEV2,
 			  enable ? ENDEV2 : 0);
 	if (ret < 0)
 		return ret;

 	ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN,
 			  enable ? CLKSKIPEN : 0);
 	if (ret < 0)
 		return ret;

 	/* FIXME: for Static ratio mode */
 	ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK,
 			  LFRATIO_12_20);
 	if (ret < 0)
 		return ret;

 	return 0;
 }

 static int cs2000_clk_in_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 cs2000_bset(priv, FUNC_CFG1,
 			   REFCLKDIV_MASK,
 			   REFCLKDIV(val));
 }

 static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
 {
 	struct device *dev = priv_to_dev(priv);
 	s32 val;
 	unsigned int i;

 	for (i = 0; i < 256; i++) {
 		val = cs2000_read(priv, DEVICE_CTRL);
 		if (val < 0)
 			return val;
 		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 cs2000_bset(priv, DEVICE_CTRL,
 			   (AUXOUTDIS | CLKOUTDIS),
 			   enable ? 0 :
 			   (AUXOUTDIS | CLKOUTDIS));
 }

 static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out)
 {
 	u64 ratio;

 	/*
 	 * ratio = rate_out / rate_in * 2^20
 	 *
 	 * To avoid over flow, rate_out is u64.
 	 * The result should be u32.
 	 */
 	ratio = (u64)rate_out << 20;
 	do_div(ratio, rate_in);

 	return ratio;
 }

 static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in)
 {
 	u64 rate_out;

 	/*
 	 * ratio = rate_out / rate_in * 2^20
 	 *
 	 * 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 >> 20;
 }

 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);
 	for (i = 0; i < RATIO_REG_SIZE; i++) {
 		ret = cs2000_write(priv,
 				   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)
 {
 	s32 tmp;
 	u32 val;
 	unsigned int i;

 	val = 0;
 	for (i = 0; i < RATIO_REG_SIZE; i++) {
 		tmp = cs2000_read(priv, Ratio_Add(ch, i));
 		if (tmp < 0)
 			return 0;

 		val |= Val_Ratio(tmp, i);
 	}

 	return val;
 }

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

 	if (CH_SIZE_ERR(ch))
 		return -EINVAL;

 	/*
 	 * FIXME
 	 *
 	 * this driver supports static ratio mode only at this point.
 	 */
 	ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
 	if (ret < 0)
 		return ret;

 	ret = cs2000_bset(priv, DEVICE_CFG2,
 			  (AUTORMOD | LOCKCLK_MASK | FRACNSRC_MASK),
 			  (LOCKCLK(ch) | FRACNSRC_STATIC));
 	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);
 }

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

 	ratio = cs2000_rate_to_ratio(*parent_rate, rate);

 	return cs2000_ratio_to_rate(ratio, *parent_rate);
 }

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

 {
 	int ret;

 	ret = cs2000_clk_in_bound_rate(priv, 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;

 	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_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)
 {
 	/* always return REF_CLK */
 	return 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];
 	int ch = 0; /* it uses ch0 only at this point */
 	int rate;
 	int ret;

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

 	/*
 	 * set default rate as 1/1.
 	 * otherwise .set_rate which setup ratio
 	 * is never called if user requests 1/1 rate
 	 */
 	rate = clk_get_rate(priv->ref_clk);
 	ret = __cs2000_set_rate(priv, ch, rate, 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);
 	s32 val;
 	const char *revision;

 	val = cs2000_read(priv, DEVICE_ID);
 	if (val < 0)
 		return val;

 	/* 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 int 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);

 	return 0;
 }

 static int cs2000_probe(struct i2c_client *client,
 			const struct i2c_device_id *id)
 {
 	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);

 	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 cs2000_resume(struct device *dev)
 {
 	struct cs2000_priv *priv = dev_get_drvdata(dev);
 	int ch = 0; /* it uses ch0 only at this point */

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

 static const struct dev_pm_ops cs2000_pm_ops = {
 	.resume_early	= cs2000_resume,
 };

 static struct i2c_driver cs2000_driver = {
 	.driver = {
 		.name = "cs2000-cp",
 		.pm	= &cs2000_pm_ops,
 		.of_match_table = cs2000_of_match,
 	},
 	.probe		= 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");
	/*
	* CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
	*
	* Copyright (C) 2015 Renesas Electronics Corporation
	* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/
	#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>

	#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 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 << 1)

	/* GLOBAL_CFG */
	#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

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

	/* 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);

	#define cs2000_read(priv, addr) \
	i2c_smbus_read_byte_data(priv_to_client(priv), addr)
	#define cs2000_write(priv, addr, val) \
	i2c_smbus_write_byte_data(priv_to_client(priv), addr, val)

	static int cs2000_bset(struct cs2000_priv *priv, u8 addr, u8 mask, u8 val)
	{
	s32 data;

	data = cs2000_read(priv, addr);
	if (data < 0)
	return data;

	data &= ~mask;
	data \|= (val & mask);

	return cs2000_write(priv, addr, data);
	}

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

	ret = cs2000_bset(priv, DEVICE_CFG1, ENDEV1,
	enable ? ENDEV1 : 0);
	if (ret < 0)
	return ret;

	ret = cs2000_bset(priv, GLOBAL_CFG, ENDEV2,
	enable ? ENDEV2 : 0);
	if (ret < 0)
	return ret;

	ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN,
	enable ? CLKSKIPEN : 0);
	if (ret < 0)
	return ret;

	/* FIXME: for Static ratio mode */
	ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK,
	LFRATIO_12_20);
	if (ret < 0)
	return ret;

	return 0;
	}

	static int cs2000_clk_in_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 cs2000_bset(priv, FUNC_CFG1,
	REFCLKDIV_MASK,
	REFCLKDIV(val));
	}

	static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
	{
	struct device *dev = priv_to_dev(priv);
	s32 val;
	unsigned int i;

	for (i = 0; i < 256; i++) {
	val = cs2000_read(priv, DEVICE_CTRL);
	if (val < 0)
	return val;
	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 cs2000_bset(priv, DEVICE_CTRL,
	(AUXOUTDIS \| CLKOUTDIS),
	enable ? 0 :
	(AUXOUTDIS \| CLKOUTDIS));
	}

	static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out)
	{
	u64 ratio;

	/*
	* ratio = rate_out / rate_in * 2^20
	*
	* To avoid over flow, rate_out is u64.
	* The result should be u32.
	*/
	ratio = (u64)rate_out << 20;
	do_div(ratio, rate_in);

	return ratio;
	}

	static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in)
	{
	u64 rate_out;

	/*
	* ratio = rate_out / rate_in * 2^20
	*
	* 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 >> 20;
	}

	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);
	for (i = 0; i < RATIO_REG_SIZE; i++) {
	ret = cs2000_write(priv,
	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)
	{
	s32 tmp;
	u32 val;
	unsigned int i;

	val = 0;
	for (i = 0; i < RATIO_REG_SIZE; i++) {
	tmp = cs2000_read(priv, Ratio_Add(ch, i));
	if (tmp < 0)
	return 0;

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

	return val;
	}

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

	if (CH_SIZE_ERR(ch))
	return -EINVAL;

	/*
	* FIXME
	*
	* this driver supports static ratio mode only at this point.
	*/
	ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
	if (ret < 0)
	return ret;

	ret = cs2000_bset(priv, DEVICE_CFG2,
	(AUTORMOD \| LOCKCLK_MASK \| FRACNSRC_MASK),
	(LOCKCLK(ch) \| FRACNSRC_STATIC));
	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);
	}

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

	ratio = cs2000_rate_to_ratio(*parent_rate, rate);

	return cs2000_ratio_to_rate(ratio, *parent_rate);
	}

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

	{
	int ret;

	ret = cs2000_clk_in_bound_rate(priv, 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;

	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_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)
	{
	/* always return REF_CLK */
	return 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];
	int ch = 0; /* it uses ch0 only at this point */
	int rate;
	int ret;

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

	/*
	* set default rate as 1/1.
	* otherwise .set_rate which setup ratio
	* is never called if user requests 1/1 rate
	*/
	rate = clk_get_rate(priv->ref_clk);
	ret = __cs2000_set_rate(priv, ch, rate, 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);
	s32 val;
	const char *revision;

	val = cs2000_read(priv, DEVICE_ID);
	if (val < 0)
	return val;

	/* 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 int 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);

	return 0;
	}

	static int cs2000_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	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);

	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 cs2000_resume(struct device *dev)
	{
	struct cs2000_priv *priv = dev_get_drvdata(dev);
	int ch = 0; /* it uses ch0 only at this point */

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

	static const struct dev_pm_ops cs2000_pm_ops = {
	.resume_early = cs2000_resume,
	};

	static struct i2c_driver cs2000_driver = {
	.driver = {
	.name = "cs2000-cp",
	.pm = &cs2000_pm_ops,
	.of_match_table = cs2000_of_match,
	},
	.probe = 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");