drivers/clk/zte/clk.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright 2014 Linaro Ltd.
  * Copyright (C) 2014 ZTE Corporation.
  *
  * 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/err.h>
 #include <linux/gcd.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <asm/div64.h>

 #include "clk.h"

 #define to_clk_zx_pll(_hw) container_of(_hw, struct clk_zx_pll, hw)
 #define to_clk_zx_audio(_hw) container_of(_hw, struct clk_zx_audio, hw)

 #define CFG0_CFG1_OFFSET 4
 #define LOCK_FLAG 30
 #define POWER_DOWN 31

 static int rate_to_idx(struct clk_zx_pll *zx_pll, unsigned long rate)
 {
 	const struct zx_pll_config *config = zx_pll->lookup_table;
 	int i;

 	for (i = 0; i < zx_pll->count; i++) {
 		if (config[i].rate > rate)
 			return i > 0 ? i - 1 : 0;

 		if (config[i].rate == rate)
 			return i;
 	}

 	return i - 1;
 }

 static int hw_to_idx(struct clk_zx_pll *zx_pll)
 {
 	const struct zx_pll_config *config = zx_pll->lookup_table;
 	u32 hw_cfg0, hw_cfg1;
 	int i;

 	hw_cfg0 = readl_relaxed(zx_pll->reg_base);
 	hw_cfg1 = readl_relaxed(zx_pll->reg_base + CFG0_CFG1_OFFSET);

 	/* For matching the value in lookup table */
 	hw_cfg0 &= ~BIT(zx_pll->lock_bit);
 	hw_cfg0 |= BIT(zx_pll->pd_bit);

 	for (i = 0; i < zx_pll->count; i++) {
 		if (hw_cfg0 == config[i].cfg0 && hw_cfg1 == config[i].cfg1)
 			return i;
 	}

 	return -EINVAL;
 }

 static unsigned long zx_pll_recalc_rate(struct clk_hw *hw,
 					unsigned long parent_rate)
 {
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	int idx;

 	idx = hw_to_idx(zx_pll);
 	if (unlikely(idx == -EINVAL))
 		return 0;

 	return zx_pll->lookup_table[idx].rate;
 }

 static long zx_pll_round_rate(struct clk_hw *hw, unsigned long rate,
 			      unsigned long *prate)
 {
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	int idx;

 	idx = rate_to_idx(zx_pll, rate);

 	return zx_pll->lookup_table[idx].rate;
 }

 static int zx_pll_set_rate(struct clk_hw *hw, unsigned long rate,
 			   unsigned long parent_rate)
 {
 	/* Assume current cpu is not running on current PLL */
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	const struct zx_pll_config *config;
 	int idx;

 	idx = rate_to_idx(zx_pll, rate);
 	config = &zx_pll->lookup_table[idx];

 	writel_relaxed(config->cfg0, zx_pll->reg_base);
 	writel_relaxed(config->cfg1, zx_pll->reg_base + CFG0_CFG1_OFFSET);

 	return 0;
 }

 static int zx_pll_enable(struct clk_hw *hw)
 {
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_pll->reg_base);
 	writel_relaxed(reg & ~BIT(zx_pll->pd_bit), zx_pll->reg_base);

 	return readl_relaxed_poll_timeout(zx_pll->reg_base, reg,
 					  reg & BIT(zx_pll->lock_bit), 0, 100);
 }

 static void zx_pll_disable(struct clk_hw *hw)
 {
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_pll->reg_base);
 	writel_relaxed(reg | BIT(zx_pll->pd_bit), zx_pll->reg_base);
 }

 static int zx_pll_is_enabled(struct clk_hw *hw)
 {
 	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_pll->reg_base);

 	return !(reg & BIT(zx_pll->pd_bit));
 }

 const struct clk_ops zx_pll_ops = {
 	.recalc_rate = zx_pll_recalc_rate,
 	.round_rate = zx_pll_round_rate,
 	.set_rate = zx_pll_set_rate,
 	.enable = zx_pll_enable,
 	.disable = zx_pll_disable,
 	.is_enabled = zx_pll_is_enabled,
 };
 EXPORT_SYMBOL(zx_pll_ops);

 struct clk *clk_register_zx_pll(const char *name, const char *parent_name,
 				unsigned long flags, void __iomem *reg_base,
 				const struct zx_pll_config *lookup_table,
 				int count, spinlock_t *lock)
 {
 	struct clk_zx_pll *zx_pll;
 	struct clk *clk;
 	struct clk_init_data init;

 	zx_pll = kzalloc(sizeof(*zx_pll), GFP_KERNEL);
 	if (!zx_pll)
 		return ERR_PTR(-ENOMEM);

 	init.name = name;
 	init.ops = &zx_pll_ops;
 	init.flags = flags;
 	init.parent_names = parent_name ? &parent_name : NULL;
 	init.num_parents = parent_name ? 1 : 0;

 	zx_pll->reg_base = reg_base;
 	zx_pll->lookup_table = lookup_table;
 	zx_pll->count = count;
 	zx_pll->lock_bit = LOCK_FLAG;
 	zx_pll->pd_bit = POWER_DOWN;
 	zx_pll->lock = lock;
 	zx_pll->hw.init = &init;

 	clk = clk_register(NULL, &zx_pll->hw);
 	if (IS_ERR(clk))
 		kfree(zx_pll);

 	return clk;
 }

 #define BPAR 1000000
 static u32 calc_reg(u32 parent_rate, u32 rate)
 {
 	u32 sel, integ, fra_div, tmp;
 	u64 tmp64 = (u64)parent_rate * BPAR;

 	do_div(tmp64, rate);
 	integ = (u32)tmp64 / BPAR;
 	integ = integ >> 1;

 	tmp = (u32)tmp64 % BPAR;
 	sel = tmp / BPAR;

 	tmp = tmp % BPAR;
 	fra_div = tmp * 0xff / BPAR;
 	tmp = (sel << 24) | (integ << 16) | (0xff << 8) | fra_div;

 	/* Set I2S integer divider as 1. This bit is reserved for SPDIF
 	 * and do no harm.
 	 */
 	tmp |= BIT(28);
 	return tmp;
 }

 static u32 calc_rate(u32 reg, u32 parent_rate)
 {
 	u32 sel, integ, fra_div, tmp;
 	u64 tmp64 = (u64)parent_rate * BPAR;

 	tmp = reg;
 	sel = (tmp >> 24) & BIT(0);
 	integ = (tmp >> 16) & 0xff;
 	fra_div = tmp & 0xff;

 	tmp = fra_div * BPAR;
 	tmp = tmp / 0xff;
 	tmp += sel * BPAR;
 	tmp += 2 * integ * BPAR;
 	do_div(tmp64, tmp);

 	return (u32)tmp64;
 }

 static unsigned long zx_audio_recalc_rate(struct clk_hw *hw,
 					  unsigned long parent_rate)
 {
 	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_audio->reg_base);
 	return calc_rate(reg, parent_rate);
 }

 static long zx_audio_round_rate(struct clk_hw *hw, unsigned long rate,
 				unsigned long *prate)
 {
 	u32 reg;

 	if (rate * 2 > *prate)
 		return -EINVAL;

 	reg = calc_reg(*prate, rate);
 	return calc_rate(reg, *prate);
 }

 static int zx_audio_set_rate(struct clk_hw *hw, unsigned long rate,
 			     unsigned long parent_rate)
 {
 	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
 	u32 reg;

 	reg = calc_reg(parent_rate, rate);
 	writel_relaxed(reg, zx_audio->reg_base);

 	return 0;
 }

 #define ZX_AUDIO_EN BIT(25)
 static int zx_audio_enable(struct clk_hw *hw)
 {
 	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_audio->reg_base);
 	writel_relaxed(reg & ~ZX_AUDIO_EN, zx_audio->reg_base);
 	return 0;
 }

 static void zx_audio_disable(struct clk_hw *hw)
 {
 	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
 	u32 reg;

 	reg = readl_relaxed(zx_audio->reg_base);
 	writel_relaxed(reg | ZX_AUDIO_EN, zx_audio->reg_base);
 }

 static const struct clk_ops zx_audio_ops = {
 	.recalc_rate = zx_audio_recalc_rate,
 	.round_rate = zx_audio_round_rate,
 	.set_rate = zx_audio_set_rate,
 	.enable = zx_audio_enable,
 	.disable = zx_audio_disable,
 };

 struct clk *clk_register_zx_audio(const char *name,
 				  const char * const parent_name,
 				  unsigned long flags,
 				  void __iomem *reg_base)
 {
 	struct clk_zx_audio *zx_audio;
 	struct clk *clk;
 	struct clk_init_data init;

 	zx_audio = kzalloc(sizeof(*zx_audio), GFP_KERNEL);
 	if (!zx_audio)
 		return ERR_PTR(-ENOMEM);

 	init.name = name;
 	init.ops = &zx_audio_ops;
 	init.flags = flags;
 	init.parent_names = parent_name ? &parent_name : NULL;
 	init.num_parents = parent_name ? 1 : 0;

 	zx_audio->reg_base = reg_base;
 	zx_audio->hw.init = &init;

 	clk = clk_register(NULL, &zx_audio->hw);
 	if (IS_ERR(clk))
 		kfree(zx_audio);

 	return clk;
 }

 #define CLK_AUDIO_DIV_FRAC	BIT(0)
 #define CLK_AUDIO_DIV_INT	BIT(1)
 #define CLK_AUDIO_DIV_UNCOMMON	BIT(1)

 #define CLK_AUDIO_DIV_FRAC_NSHIFT	16
 #define CLK_AUDIO_DIV_INT_FRAC_RE	BIT(16)
 #define CLK_AUDIO_DIV_INT_FRAC_MAX	(0xffff)
 #define CLK_AUDIO_DIV_INT_FRAC_MIN	(0x2)
 #define CLK_AUDIO_DIV_INT_INT_SHIFT	24
 #define CLK_AUDIO_DIV_INT_INT_WIDTH	4

 struct zx_clk_audio_div_table {
 	unsigned long rate;
 	unsigned int int_reg;
 	unsigned int frac_reg;
 };

 #define to_clk_zx_audio_div(_hw) container_of(_hw, struct clk_zx_audio_divider, hw)

 static unsigned long audio_calc_rate(struct clk_zx_audio_divider *audio_div,
 				     u32 reg_frac, u32 reg_int,
 				     unsigned long parent_rate)
 {
 	unsigned long rate, m, n;

 	m = reg_frac & 0xffff;
 	n = (reg_frac >> 16) & 0xffff;

 	m = (reg_int & 0xffff) * n + m;
 	rate = (parent_rate * n) / m;

 	return rate;
 }

 static void audio_calc_reg(struct clk_zx_audio_divider *audio_div,
 			   struct zx_clk_audio_div_table *div_table,
 			   unsigned long rate, unsigned long parent_rate)
 {
 	unsigned int reg_int, reg_frac;
 	unsigned long m, n, div;

 	reg_int = parent_rate / rate;

 	if (reg_int > CLK_AUDIO_DIV_INT_FRAC_MAX)
 		reg_int = CLK_AUDIO_DIV_INT_FRAC_MAX;
 	else if (reg_int < CLK_AUDIO_DIV_INT_FRAC_MIN)
 		reg_int = 0;
 	m = parent_rate - rate * reg_int;
 	n = rate;

 	div = gcd(m, n);
 	m = m / div;
 	n = n / div;

 	if ((m >> 16) || (n >> 16)) {
 		if (m > n) {
 			n = n * 0xffff / m;
 			m = 0xffff;
 		} else {
 			m = m * 0xffff / n;
 			n = 0xffff;
 		}
 	}
 	reg_frac = m | (n << 16);

 	div_table->rate = parent_rate * n / (reg_int * n + m);
 	div_table->int_reg = reg_int;
 	div_table->frac_reg = reg_frac;
 }

 static unsigned long zx_audio_div_recalc_rate(struct clk_hw *hw,
 					  unsigned long parent_rate)
 {
 	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
 	u32 reg_frac, reg_int;

 	reg_frac = readl_relaxed(zx_audio_div->reg_base);
 	reg_int = readl_relaxed(zx_audio_div->reg_base + 0x4);

 	return audio_calc_rate(zx_audio_div, reg_frac, reg_int, parent_rate);
 }

 static long zx_audio_div_round_rate(struct clk_hw *hw, unsigned long rate,
 				unsigned long *prate)
 {
 	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
 	struct zx_clk_audio_div_table divt;

 	audio_calc_reg(zx_audio_div, &divt, rate, *prate);

 	return audio_calc_rate(zx_audio_div, divt.frac_reg, divt.int_reg, *prate);
 }

 static int zx_audio_div_set_rate(struct clk_hw *hw, unsigned long rate,
 				    unsigned long parent_rate)
 {
 	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
 	struct zx_clk_audio_div_table divt;
 	unsigned int val;

 	audio_calc_reg(zx_audio_div, &divt, rate, parent_rate);
 	if (divt.rate != rate)
 		pr_debug("the real rate is:%ld", divt.rate);

 	writel_relaxed(divt.frac_reg, zx_audio_div->reg_base);

 	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
 	val &= ~0xffff;
 	val |= divt.int_reg | CLK_AUDIO_DIV_INT_FRAC_RE;
 	writel_relaxed(val, zx_audio_div->reg_base + 0x4);

 	mdelay(1);

 	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
 	val &= ~CLK_AUDIO_DIV_INT_FRAC_RE;
 	writel_relaxed(val, zx_audio_div->reg_base + 0x4);

 	return 0;
 }

 const struct clk_ops zx_audio_div_ops = {
 	.recalc_rate = zx_audio_div_recalc_rate,
 	.round_rate = zx_audio_div_round_rate,
 	.set_rate = zx_audio_div_set_rate,
 };
	/*
	* Copyright 2014 Linaro Ltd.
	* Copyright (C) 2014 ZTE Corporation.
	*
	* 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/err.h>
	#include <linux/gcd.h>
	#include <linux/io.h>
	#include <linux/iopoll.h>
	#include <linux/slab.h>
	#include <linux/spinlock.h>
	#include <asm/div64.h>

	#include "clk.h"

	#define to_clk_zx_pll(_hw) container_of(_hw, struct clk_zx_pll, hw)
	#define to_clk_zx_audio(_hw) container_of(_hw, struct clk_zx_audio, hw)

	#define CFG0_CFG1_OFFSET 4
	#define LOCK_FLAG 30
	#define POWER_DOWN 31

	static int rate_to_idx(struct clk_zx_pll *zx_pll, unsigned long rate)
	{
	const struct zx_pll_config *config = zx_pll->lookup_table;
	int i;

	for (i = 0; i < zx_pll->count; i++) {
	if (config[i].rate > rate)
	return i > 0 ? i - 1 : 0;

	if (config[i].rate == rate)
	return i;
	}

	return i - 1;
	}

	static int hw_to_idx(struct clk_zx_pll *zx_pll)
	{
	const struct zx_pll_config *config = zx_pll->lookup_table;
	u32 hw_cfg0, hw_cfg1;
	int i;

	hw_cfg0 = readl_relaxed(zx_pll->reg_base);
	hw_cfg1 = readl_relaxed(zx_pll->reg_base + CFG0_CFG1_OFFSET);

	/* For matching the value in lookup table */
	hw_cfg0 &= ~BIT(zx_pll->lock_bit);
	hw_cfg0 \|= BIT(zx_pll->pd_bit);

	for (i = 0; i < zx_pll->count; i++) {
	if (hw_cfg0 == config[i].cfg0 && hw_cfg1 == config[i].cfg1)
	return i;
	}

	return -EINVAL;
	}

	static unsigned long zx_pll_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	int idx;

	idx = hw_to_idx(zx_pll);
	if (unlikely(idx == -EINVAL))
	return 0;

	return zx_pll->lookup_table[idx].rate;
	}

	static long zx_pll_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *prate)
	{
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	int idx;

	idx = rate_to_idx(zx_pll, rate);

	return zx_pll->lookup_table[idx].rate;
	}

	static int zx_pll_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	/* Assume current cpu is not running on current PLL */
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	const struct zx_pll_config *config;
	int idx;

	idx = rate_to_idx(zx_pll, rate);
	config = &zx_pll->lookup_table[idx];

	writel_relaxed(config->cfg0, zx_pll->reg_base);
	writel_relaxed(config->cfg1, zx_pll->reg_base + CFG0_CFG1_OFFSET);

	return 0;
	}

	static int zx_pll_enable(struct clk_hw *hw)
	{
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	u32 reg;

	reg = readl_relaxed(zx_pll->reg_base);
	writel_relaxed(reg & ~BIT(zx_pll->pd_bit), zx_pll->reg_base);

	return readl_relaxed_poll_timeout(zx_pll->reg_base, reg,
	reg & BIT(zx_pll->lock_bit), 0, 100);
	}

	static void zx_pll_disable(struct clk_hw *hw)
	{
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	u32 reg;

	reg = readl_relaxed(zx_pll->reg_base);
	writel_relaxed(reg \| BIT(zx_pll->pd_bit), zx_pll->reg_base);
	}

	static int zx_pll_is_enabled(struct clk_hw *hw)
	{
	struct clk_zx_pll *zx_pll = to_clk_zx_pll(hw);
	u32 reg;

	reg = readl_relaxed(zx_pll->reg_base);

	return !(reg & BIT(zx_pll->pd_bit));
	}

	const struct clk_ops zx_pll_ops = {
	.recalc_rate = zx_pll_recalc_rate,
	.round_rate = zx_pll_round_rate,
	.set_rate = zx_pll_set_rate,
	.enable = zx_pll_enable,
	.disable = zx_pll_disable,
	.is_enabled = zx_pll_is_enabled,
	};
	EXPORT_SYMBOL(zx_pll_ops);

	struct clk clk_register_zx_pll(const char name, const char *parent_name,
	unsigned long flags, void __iomem *reg_base,
	const struct zx_pll_config *lookup_table,
	int count, spinlock_t *lock)
	{
	struct clk_zx_pll *zx_pll;
	struct clk *clk;
	struct clk_init_data init;

	zx_pll = kzalloc(sizeof(*zx_pll), GFP_KERNEL);
	if (!zx_pll)
	return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &zx_pll_ops;
	init.flags = flags;
	init.parent_names = parent_name ? &parent_name : NULL;
	init.num_parents = parent_name ? 1 : 0;

	zx_pll->reg_base = reg_base;
	zx_pll->lookup_table = lookup_table;
	zx_pll->count = count;
	zx_pll->lock_bit = LOCK_FLAG;
	zx_pll->pd_bit = POWER_DOWN;
	zx_pll->lock = lock;
	zx_pll->hw.init = &init;

	clk = clk_register(NULL, &zx_pll->hw);
	if (IS_ERR(clk))
	kfree(zx_pll);

	return clk;
	}

	#define BPAR 1000000
	static u32 calc_reg(u32 parent_rate, u32 rate)
	{
	u32 sel, integ, fra_div, tmp;
	u64 tmp64 = (u64)parent_rate * BPAR;

	do_div(tmp64, rate);
	integ = (u32)tmp64 / BPAR;
	integ = integ >> 1;

	tmp = (u32)tmp64 % BPAR;
	sel = tmp / BPAR;

	tmp = tmp % BPAR;
	fra_div = tmp * 0xff / BPAR;
	tmp = (sel << 24) \| (integ << 16) \| (0xff << 8) \| fra_div;

	/* Set I2S integer divider as 1. This bit is reserved for SPDIF
	* and do no harm.
	*/
	tmp \|= BIT(28);
	return tmp;
	}

	static u32 calc_rate(u32 reg, u32 parent_rate)
	{
	u32 sel, integ, fra_div, tmp;
	u64 tmp64 = (u64)parent_rate * BPAR;

	tmp = reg;
	sel = (tmp >> 24) & BIT(0);
	integ = (tmp >> 16) & 0xff;
	fra_div = tmp & 0xff;

	tmp = fra_div * BPAR;
	tmp = tmp / 0xff;
	tmp += sel * BPAR;
	tmp += 2 * integ * BPAR;
	do_div(tmp64, tmp);

	return (u32)tmp64;
	}

	static unsigned long zx_audio_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
	u32 reg;

	reg = readl_relaxed(zx_audio->reg_base);
	return calc_rate(reg, parent_rate);
	}

	static long zx_audio_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *prate)
	{
	u32 reg;

	if (rate * 2 > *prate)
	return -EINVAL;

	reg = calc_reg(*prate, rate);
	return calc_rate(reg, *prate);
	}

	static int zx_audio_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
	u32 reg;

	reg = calc_reg(parent_rate, rate);
	writel_relaxed(reg, zx_audio->reg_base);

	return 0;
	}

	#define ZX_AUDIO_EN BIT(25)
	static int zx_audio_enable(struct clk_hw *hw)
	{
	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
	u32 reg;

	reg = readl_relaxed(zx_audio->reg_base);
	writel_relaxed(reg & ~ZX_AUDIO_EN, zx_audio->reg_base);
	return 0;
	}

	static void zx_audio_disable(struct clk_hw *hw)
	{
	struct clk_zx_audio *zx_audio = to_clk_zx_audio(hw);
	u32 reg;

	reg = readl_relaxed(zx_audio->reg_base);
	writel_relaxed(reg \| ZX_AUDIO_EN, zx_audio->reg_base);
	}

	static const struct clk_ops zx_audio_ops = {
	.recalc_rate = zx_audio_recalc_rate,
	.round_rate = zx_audio_round_rate,
	.set_rate = zx_audio_set_rate,
	.enable = zx_audio_enable,
	.disable = zx_audio_disable,
	};

	struct clk clk_register_zx_audio(const char name,
	const char * const parent_name,
	unsigned long flags,
	void __iomem *reg_base)
	{
	struct clk_zx_audio *zx_audio;
	struct clk *clk;
	struct clk_init_data init;

	zx_audio = kzalloc(sizeof(*zx_audio), GFP_KERNEL);
	if (!zx_audio)
	return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &zx_audio_ops;
	init.flags = flags;
	init.parent_names = parent_name ? &parent_name : NULL;
	init.num_parents = parent_name ? 1 : 0;

	zx_audio->reg_base = reg_base;
	zx_audio->hw.init = &init;

	clk = clk_register(NULL, &zx_audio->hw);
	if (IS_ERR(clk))
	kfree(zx_audio);

	return clk;
	}

	#define CLK_AUDIO_DIV_FRAC BIT(0)
	#define CLK_AUDIO_DIV_INT BIT(1)
	#define CLK_AUDIO_DIV_UNCOMMON BIT(1)

	#define CLK_AUDIO_DIV_FRAC_NSHIFT 16
	#define CLK_AUDIO_DIV_INT_FRAC_RE BIT(16)
	#define CLK_AUDIO_DIV_INT_FRAC_MAX (0xffff)
	#define CLK_AUDIO_DIV_INT_FRAC_MIN (0x2)
	#define CLK_AUDIO_DIV_INT_INT_SHIFT 24
	#define CLK_AUDIO_DIV_INT_INT_WIDTH 4

	struct zx_clk_audio_div_table {
	unsigned long rate;
	unsigned int int_reg;
	unsigned int frac_reg;
	};

	#define to_clk_zx_audio_div(_hw) container_of(_hw, struct clk_zx_audio_divider, hw)

	static unsigned long audio_calc_rate(struct clk_zx_audio_divider *audio_div,
	u32 reg_frac, u32 reg_int,
	unsigned long parent_rate)
	{
	unsigned long rate, m, n;

	m = reg_frac & 0xffff;
	n = (reg_frac >> 16) & 0xffff;

	m = (reg_int & 0xffff) * n + m;
	rate = (parent_rate * n) / m;

	return rate;
	}

	static void audio_calc_reg(struct clk_zx_audio_divider *audio_div,
	struct zx_clk_audio_div_table *div_table,
	unsigned long rate, unsigned long parent_rate)
	{
	unsigned int reg_int, reg_frac;
	unsigned long m, n, div;

	reg_int = parent_rate / rate;

	if (reg_int > CLK_AUDIO_DIV_INT_FRAC_MAX)
	reg_int = CLK_AUDIO_DIV_INT_FRAC_MAX;
	else if (reg_int < CLK_AUDIO_DIV_INT_FRAC_MIN)
	reg_int = 0;
	m = parent_rate - rate * reg_int;
	n = rate;

	div = gcd(m, n);
	m = m / div;
	n = n / div;

	if ((m >> 16) \|\| (n >> 16)) {
	if (m > n) {
	n = n * 0xffff / m;
	m = 0xffff;
	} else {
	m = m * 0xffff / n;
	n = 0xffff;
	}
	}
	reg_frac = m \| (n << 16);

	div_table->rate = parent_rate * n / (reg_int * n + m);
	div_table->int_reg = reg_int;
	div_table->frac_reg = reg_frac;
	}

	static unsigned long zx_audio_div_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
	u32 reg_frac, reg_int;

	reg_frac = readl_relaxed(zx_audio_div->reg_base);
	reg_int = readl_relaxed(zx_audio_div->reg_base + 0x4);

	return audio_calc_rate(zx_audio_div, reg_frac, reg_int, parent_rate);
	}

	static long zx_audio_div_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *prate)
	{
	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
	struct zx_clk_audio_div_table divt;

	audio_calc_reg(zx_audio_div, &divt, rate, *prate);

	return audio_calc_rate(zx_audio_div, divt.frac_reg, divt.int_reg, *prate);
	}

	static int zx_audio_div_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct clk_zx_audio_divider *zx_audio_div = to_clk_zx_audio_div(hw);
	struct zx_clk_audio_div_table divt;
	unsigned int val;

	audio_calc_reg(zx_audio_div, &divt, rate, parent_rate);
	if (divt.rate != rate)
	pr_debug("the real rate is:%ld", divt.rate);

	writel_relaxed(divt.frac_reg, zx_audio_div->reg_base);

	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
	val &= ~0xffff;
	val \|= divt.int_reg \| CLK_AUDIO_DIV_INT_FRAC_RE;
	writel_relaxed(val, zx_audio_div->reg_base + 0x4);

	mdelay(1);

	val = readl_relaxed(zx_audio_div->reg_base + 0x4);
	val &= ~CLK_AUDIO_DIV_INT_FRAC_RE;
	writel_relaxed(val, zx_audio_div->reg_base + 0x4);

	return 0;
	}

	const struct clk_ops zx_audio_div_ops = {
	.recalc_rate = zx_audio_div_recalc_rate,
	.round_rate = zx_audio_div_round_rate,
	.set_rate = zx_audio_div_set_rate,
	};