[linux-block.git] / drivers / clk / clk-cs2000-cp.c

/*
 * 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_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)
{
	/* 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 __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		= 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");
Commit	Line	Data
64dfbe24 KM	1	/*
	2	* CS2000 -- CIRRUS LOGIC Fractional-N Clock Synthesizer & Clock Multiplier
	3	*
	4	* Copyright (C) 2015 Renesas Electronics Corporation
	5	* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#include <linux/clk-provider.h>
	12	#include <linux/delay.h>
	13	#include <linux/clk.h>
	14	#include <linux/i2c.h>
	15	#include <linux/of_device.h>
	16	#include <linux/module.h>
	17
	18	#define CH_MAX 4
	19	#define RATIO_REG_SIZE 4
	20
	21	#define DEVICE_ID 0x1
	22	#define DEVICE_CTRL 0x2
	23	#define DEVICE_CFG1 0x3
	24	#define DEVICE_CFG2 0x4
	25	#define GLOBAL_CFG 0x5
	26	#define Ratio_Add(x, nth) (6 + (x * 4) + (nth))
	27	#define Ratio_Val(x, nth) ((x >> (24 - (8 * nth))) & 0xFF)
	28	#define Val_Ratio(x, nth) ((x & 0xFF) << (24 - (8 * nth)))
	29	#define FUNC_CFG1 0x16
	30	#define FUNC_CFG2 0x17
	31
	32	/* DEVICE_ID */
	33	#define REVISION_MASK (0x7)
	34	#define REVISION_B2_B3 (0x4)
	35	#define REVISION_C1 (0x6)
	36
	37	/* DEVICE_CTRL */
	38	#define PLL_UNLOCK (1 << 7)
1f9dfd7a KM	39	#define AUXOUTDIS (1 << 1)
1f9dfd7a KM	40	#define CLKOUTDIS (1 << 0)
64dfbe24 KM	41
	42	/* DEVICE_CFG1 */
	43	#define RSEL(x) (((x) & 0x3) << 3)
	44	#define RSEL_MASK RSEL(0x3)
	45	#define ENDEV1 (0x1)
	46
1f9dfd7a KM	47	/* DEVICE_CFG2 */
	48	#define AUTORMOD (1 << 3)
	49	#define LOCKCLK(x) (((x) & 0x3) << 1)
	50	#define LOCKCLK_MASK LOCKCLK(0x3)
b295a015 KM	51	#define FRACNSRC_MASK (1 << 0)
	52	#define FRACNSRC_STATIC (0 << 0)
	53	#define FRACNSRC_DYNAMIC (1 << 1)
1f9dfd7a	54
64dfbe24 KM	55	/* GLOBAL_CFG */
	56	#define ENDEV2 (0x1)
	57
1f9dfd7a	58	/* FUNC_CFG1 */
d127967a	59	#define CLKSKIPEN (1 << 7)
1f9dfd7a KM	60	#define REFCLKDIV(x) (((x) & 0x3) << 3)
	61	#define REFCLKDIV_MASK REFCLKDIV(0x3)
	62
b3da896e KM	63	/* FUNC_CFG2 */
	64	#define LFRATIO_MASK (1 << 3)
	65	#define LFRATIO_20_12 (0 << 3)
	66	#define LFRATIO_12_20 (1 << 3)
	67
64dfbe24 KM	68	#define CH_SIZE_ERR(ch) ((ch < 0) \|\| (ch >= CH_MAX))
	69	#define hw_to_priv(_hw) container_of(_hw, struct cs2000_priv, hw)
	70	#define priv_to_client(priv) (priv->client)
	71	#define priv_to_dev(priv) (&(priv_to_client(priv)->dev))
	72
	73	#define CLK_IN 0
	74	#define REF_CLK 1
	75	#define CLK_MAX 2
	76
	77	struct cs2000_priv {
	78	struct clk_hw hw;
	79	struct i2c_client *client;
	80	struct clk *clk_in;
	81	struct clk *ref_clk;
c567fb37 KN	82
	83	/* suspend/resume */
	84	unsigned long saved_rate;
	85	unsigned long saved_parent_rate;
64dfbe24 KM	86	};
	87
	88	static const struct of_device_id cs2000_of_match[] = {
	89	{ .compatible = "cirrus,cs2000-cp", },
	90	{},
	91	};
	92	MODULE_DEVICE_TABLE(of, cs2000_of_match);
	93
	94	static const struct i2c_device_id cs2000_id[] = {
	95	{ "cs2000-cp", },
	96	{}
	97	};
	98	MODULE_DEVICE_TABLE(i2c, cs2000_id);
	99
	100	#define cs2000_read(priv, addr) \
	101	i2c_smbus_read_byte_data(priv_to_client(priv), addr)
	102	#define cs2000_write(priv, addr, val) \
	103	i2c_smbus_write_byte_data(priv_to_client(priv), addr, val)
	104
	105	static int cs2000_bset(struct cs2000_priv *priv, u8 addr, u8 mask, u8 val)
	106	{
	107	s32 data;
	108
	109	data = cs2000_read(priv, addr);
	110	if (data < 0)
	111	return data;
	112
	113	data &= ~mask;
	114	data \|= (val & mask);
	115
	116	return cs2000_write(priv, addr, data);
	117	}
	118
	119	static int cs2000_enable_dev_config(struct cs2000_priv *priv, bool enable)
	120	{
	121	int ret;
	122
	123	ret = cs2000_bset(priv, DEVICE_CFG1, ENDEV1,
	124	enable ? ENDEV1 : 0);
	125	if (ret < 0)
	126	return ret;
	127
	128	ret = cs2000_bset(priv, GLOBAL_CFG, ENDEV2,
	129	enable ? ENDEV2 : 0);
	130	if (ret < 0)
	131	return ret;
	132
d127967a KM	133	ret = cs2000_bset(priv, FUNC_CFG1, CLKSKIPEN,
	134	enable ? CLKSKIPEN : 0);
	135	if (ret < 0)
	136	return ret;
	137
b3da896e KM	138	/* FIXME: for Static ratio mode */
	139	ret = cs2000_bset(priv, FUNC_CFG2, LFRATIO_MASK,
	140	LFRATIO_12_20);
	141	if (ret < 0)
	142	return ret;
	143
64dfbe24 KM	144	return 0;
	145	}
	146
	147	static int cs2000_clk_in_bound_rate(struct cs2000_priv *priv,
	148	u32 rate_in)
	149	{
	150	u32 val;
	151
	152	if (rate_in >= 32000000 && rate_in < 56000000)
	153	val = 0x0;
	154	else if (rate_in >= 16000000 && rate_in < 28000000)
	155	val = 0x1;
	156	else if (rate_in >= 8000000 && rate_in < 14000000)
	157	val = 0x2;
	158	else
	159	return -EINVAL;
	160
1f9dfd7a KM	161	return cs2000_bset(priv, FUNC_CFG1,
	162	REFCLKDIV_MASK,
	163	REFCLKDIV(val));
64dfbe24 KM	164	}
	165
	166	static int cs2000_wait_pll_lock(struct cs2000_priv *priv)
	167	{
	168	struct device *dev = priv_to_dev(priv);
	169	s32 val;
	170	unsigned int i;
	171
	172	for (i = 0; i < 256; i++) {
	173	val = cs2000_read(priv, DEVICE_CTRL);
	174	if (val < 0)
	175	return val;
	176	if (!(val & PLL_UNLOCK))
	177	return 0;
	178	udelay(1);
	179	}
	180
	181	dev_err(dev, "pll lock failed\n");
	182
	183	return -ETIMEDOUT;
	184	}
	185
	186	static int cs2000_clk_out_enable(struct cs2000_priv *priv, bool enable)
	187	{
	188	/* enable both AUX_OUT, CLK_OUT */
1f9dfd7a KM	189	return cs2000_bset(priv, DEVICE_CTRL,
	190	(AUXOUTDIS \| CLKOUTDIS),
	191	enable ? 0 :
	192	(AUXOUTDIS \| CLKOUTDIS));
64dfbe24 KM	193	}
	194
	195	static u32 cs2000_rate_to_ratio(u32 rate_in, u32 rate_out)
	196	{
	197	u64 ratio;
	198
	199	/*
	200	* ratio = rate_out / rate_in * 2^20
	201	*
	202	* To avoid over flow, rate_out is u64.
	203	* The result should be u32.
	204	*/
	205	ratio = (u64)rate_out << 20;
	206	do_div(ratio, rate_in);
	207
	208	return ratio;
	209	}
	210
	211	static unsigned long cs2000_ratio_to_rate(u32 ratio, u32 rate_in)
	212	{
	213	u64 rate_out;
	214
	215	/*
	216	* ratio = rate_out / rate_in * 2^20
	217	*
	218	* To avoid over flow, rate_out is u64.
	219	* The result should be u32 or unsigned long.
	220	*/
	221
	222	rate_out = (u64)ratio * rate_in;
	223	return rate_out >> 20;
	224	}
	225
	226	static int cs2000_ratio_set(struct cs2000_priv *priv,
	227	int ch, u32 rate_in, u32 rate_out)
	228	{
	229	u32 val;
	230	unsigned int i;
	231	int ret;
	232
	233	if (CH_SIZE_ERR(ch))
	234	return -EINVAL;
	235
	236	val = cs2000_rate_to_ratio(rate_in, rate_out);
	237	for (i = 0; i < RATIO_REG_SIZE; i++) {
	238	ret = cs2000_write(priv,
	239	Ratio_Add(ch, i),
	240	Ratio_Val(val, i));
	241	if (ret < 0)
	242	return ret;
	243	}
	244
	245	return 0;
	246	}
	247
	248	static u32 cs2000_ratio_get(struct cs2000_priv *priv, int ch)
	249	{
	250	s32 tmp;
	251	u32 val;
	252	unsigned int i;
	253
	254	val = 0;
	255	for (i = 0; i < RATIO_REG_SIZE; i++) {
	256	tmp = cs2000_read(priv, Ratio_Add(ch, i));
257	if (tmp < 0)
258	return 0;
259
260	val \|= Val_Ratio(tmp, i);
261	}
262
263	return val;
264	}
265
266	static int cs2000_ratio_select(struct cs2000_priv *priv, int ch)
267	{
268	int ret;
269
270	if (CH_SIZE_ERR(ch))
271	return -EINVAL;
272
273	/*
274	* FIXME
275	*
276	* this driver supports static ratio mode only at this point.
277	*/
278	ret = cs2000_bset(priv, DEVICE_CFG1, RSEL_MASK, RSEL(ch));
279	if (ret < 0)
280	return ret;
281
1f9dfd7a	282	ret = cs2000_bset(priv, DEVICE_CFG2,
b295a015 KM	283	(AUTORMOD \| LOCKCLK_MASK \| FRACNSRC_MASK),
b295a015 KM	284	(LOCKCLK(ch) \| FRACNSRC_STATIC));
64dfbe24 KM	285	if (ret < 0)
	286	return ret;
	287
	288	return 0;
	289	}
	290
	291	static unsigned long cs2000_recalc_rate(struct clk_hw *hw,
	292	unsigned long parent_rate)
	293	{
	294	struct cs2000_priv *priv = hw_to_priv(hw);
	295	int ch = 0; /* it uses ch0 only at this point */
	296	u32 ratio;
	297
	298	ratio = cs2000_ratio_get(priv, ch);
	299
	300	return cs2000_ratio_to_rate(ratio, parent_rate);
	301	}
	302
	303	static long cs2000_round_rate(struct clk_hw *hw, unsigned long rate,
	304	unsigned long *parent_rate)
	305	{
	306	u32 ratio;
	307
	308	ratio = cs2000_rate_to_ratio(*parent_rate, rate);
	309
	310	return cs2000_ratio_to_rate(ratio, *parent_rate);
	311	}
	312
	313	static int __cs2000_set_rate(struct cs2000_priv *priv, int ch,
	314	unsigned long rate, unsigned long parent_rate)
	315
	316	{
	317	int ret;
	318
	319	ret = cs2000_clk_in_bound_rate(priv, parent_rate);
	320	if (ret < 0)
	321	return ret;
	322
	323	ret = cs2000_ratio_set(priv, ch, parent_rate, rate);
	324	if (ret < 0)
	325	return ret;
	326
	327	ret = cs2000_ratio_select(priv, ch);
	328	if (ret < 0)
	329	return ret;
	330
c567fb37 KN	331	priv->saved_rate = rate;
	332	priv->saved_parent_rate = parent_rate;
	333
64dfbe24 KM	334	return 0;
	335	}
	336
	337	static int cs2000_set_rate(struct clk_hw *hw,
	338	unsigned long rate, unsigned long parent_rate)
	339	{
	340	struct cs2000_priv *priv = hw_to_priv(hw);
	341	int ch = 0; /* it uses ch0 only at this point */
	342
	343	return __cs2000_set_rate(priv, ch, rate, parent_rate);
	344	}
	345
e001525c GI	346	static int cs2000_set_saved_rate(struct cs2000_priv *priv)
	347	{
	348	int ch = 0; /* it uses ch0 only at this point */
	349
	350	return __cs2000_set_rate(priv, ch,
	351	priv->saved_rate,
	352	priv->saved_parent_rate);
	353	}
	354
64dfbe24 KM	355	static int cs2000_enable(struct clk_hw *hw)
	356	{
	357	struct cs2000_priv *priv = hw_to_priv(hw);
	358	int ret;
	359
	360	ret = cs2000_enable_dev_config(priv, true);
	361	if (ret < 0)
	362	return ret;
	363
	364	ret = cs2000_clk_out_enable(priv, true);
	365	if (ret < 0)
	366	return ret;
	367
	368	ret = cs2000_wait_pll_lock(priv);
	369	if (ret < 0)
	370	return ret;
	371
	372	return ret;
	373	}
	374
	375	static void cs2000_disable(struct clk_hw *hw)
	376	{
	377	struct cs2000_priv *priv = hw_to_priv(hw);
	378
	379	cs2000_enable_dev_config(priv, false);
	380
	381	cs2000_clk_out_enable(priv, false);
	382	}
	383
	384	static u8 cs2000_get_parent(struct clk_hw *hw)
	385	{
	386	/* always return REF_CLK */
	387	return REF_CLK;
	388	}
	389
	390	static const struct clk_ops cs2000_ops = {
	391	.get_parent = cs2000_get_parent,
	392	.recalc_rate = cs2000_recalc_rate,
	393	.round_rate = cs2000_round_rate,
	394	.set_rate = cs2000_set_rate,
	395	.prepare = cs2000_enable,
	396	.unprepare = cs2000_disable,
	397	};
	398
	399	static int cs2000_clk_get(struct cs2000_priv *priv)
	400	{
83dd720d	401	struct device *dev = priv_to_dev(priv);
64dfbe24 KM	402	struct clk clk_in, ref_clk;
	403
	404	clk_in = devm_clk_get(dev, "clk_in");
	405	/* not yet provided */
	406	if (IS_ERR(clk_in))
	407	return -EPROBE_DEFER;
	408
	409	ref_clk = devm_clk_get(dev, "ref_clk");
	410	/* not yet provided */
	411	if (IS_ERR(ref_clk))
	412	return -EPROBE_DEFER;
	413
	414	priv->clk_in = clk_in;
	415	priv->ref_clk = ref_clk;
	416
	417	return 0;
	418	}
	419
	420	static int cs2000_clk_register(struct cs2000_priv *priv)
	421	{
	422	struct device *dev = priv_to_dev(priv);
	423	struct device_node *np = dev->of_node;
	424	struct clk_init_data init;
	425	const char *name = np->name;
64dfbe24 KM	426	static const char *parent_names[CLK_MAX];
	427	int ch = 0; /* it uses ch0 only at this point */
	428	int rate;
	429	int ret;
	430
	431	of_property_read_string(np, "clock-output-names", &name);
	432
	433	/*
	434	* set default rate as 1/1.
	435	* otherwise .set_rate which setup ratio
	436	* is never called if user requests 1/1 rate
	437	*/
	438	rate = clk_get_rate(priv->ref_clk);
	439	ret = __cs2000_set_rate(priv, ch, rate, rate);
	440	if (ret < 0)
	441	return ret;
	442
	443	parent_names[CLK_IN] = __clk_get_name(priv->clk_in);
	444	parent_names[REF_CLK] = __clk_get_name(priv->ref_clk);
	445
	446	init.name = name;
	447	init.ops = &cs2000_ops;
	448	init.flags = CLK_SET_RATE_GATE;
	449	init.parent_names = parent_names;
	450	init.num_parents = ARRAY_SIZE(parent_names);
	451
	452	priv->hw.init = &init;
	453
2ceb3c7a SB	454	ret = clk_hw_register(dev, &priv->hw);
	455	if (ret)
	456	return ret;
64dfbe24	457
2ceb3c7a	458	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
64dfbe24	459	if (ret < 0) {
2ceb3c7a	460	clk_hw_unregister(&priv->hw);
64dfbe24 KM	461	return ret;
	462	}
	463
64dfbe24 KM	464	return 0;
	465	}
	466
	467	static int cs2000_version_print(struct cs2000_priv *priv)
	468	{
83dd720d	469	struct device *dev = priv_to_dev(priv);
64dfbe24 KM	470	s32 val;
	471	const char *revision;
	472
	473	val = cs2000_read(priv, DEVICE_ID);
	474	if (val < 0)
	475	return val;
	476
	477	/* CS2000 should be 0x0 */
	478	if (val >> 3)
	479	return -EIO;
	480
	481	switch (val & REVISION_MASK) {
	482	case REVISION_B2_B3:
	483	revision = "B2 / B3";
	484	break;
	485	case REVISION_C1:
	486	revision = "C1";
	487	break;
	488	default:
	489	return -EIO;
	490	}
	491
	492	dev_info(dev, "revision - %s\n", revision);
	493
	494	return 0;
	495	}
	496
	497	static int cs2000_remove(struct i2c_client *client)
	498	{
	499	struct cs2000_priv *priv = i2c_get_clientdata(client);
83dd720d	500	struct device *dev = priv_to_dev(priv);
64dfbe24 KM	501	struct device_node *np = dev->of_node;
	502
	503	of_clk_del_provider(np);
	504
2ceb3c7a	505	clk_hw_unregister(&priv->hw);
64dfbe24 KM	506
	507	return 0;
	508	}
	509
	510	static int cs2000_probe(struct i2c_client *client,
	511	const struct i2c_device_id *id)
	512	{
	513	struct cs2000_priv *priv;
	514	struct device *dev = &client->dev;
	515	int ret;
	516
	517	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	518	if (!priv)
	519	return -ENOMEM;
	520
	521	priv->client = client;
	522	i2c_set_clientdata(client, priv);
	523
	524	ret = cs2000_clk_get(priv);
	525	if (ret < 0)
	526	return ret;
	527
	528	ret = cs2000_clk_register(priv);
	529	if (ret < 0)
	530	return ret;
	531
	532	ret = cs2000_version_print(priv);
	533	if (ret < 0)
	534	goto probe_err;
	535
	536	return 0;
	537
	538	probe_err:
	539	cs2000_remove(client);
	540
	541	return ret;
	542	}
	543
a21b8594	544	static int __maybe_unused cs2000_resume(struct device *dev)
c567fb37 KN	545	{
c567fb37 KN	546	struct cs2000_priv *priv = dev_get_drvdata(dev);
c567fb37	547
e001525c	548	return cs2000_set_saved_rate(priv);
c567fb37 KN	549	}
	550
	551	static const struct dev_pm_ops cs2000_pm_ops = {
eade4ccd	552	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, cs2000_resume)
c567fb37 KN	553	};
c567fb37 KN	554
64dfbe24 KM	555	static struct i2c_driver cs2000_driver = {
	556	.driver = {
	557	.name = "cs2000-cp",
c567fb37	558	.pm = &cs2000_pm_ops,
64dfbe24 KM	559	.of_match_table = cs2000_of_match,
	560	},
	561	.probe = cs2000_probe,
	562	.remove = cs2000_remove,
	563	.id_table = cs2000_id,
	564	};
	565
	566	module_i2c_driver(cs2000_driver);
	567
	568	MODULE_DESCRIPTION("CS2000-CP driver");
	569	MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");
	570	MODULE_LICENSE("GPL v2");