drivers/clk/clk-wm831x.c - linux/kernel/git/viro/vfs - Git at Google

 /*
  * WM831x clock control
  *
  * Copyright 2011-2 Wolfson Microelectronics PLC.
  *
  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  *
  *  This program is free software; you can redistribute  it and/or modify it
  *  under  the terms of  the GNU General  Public License as published by the
  *  Free Software Foundation;  either version 2 of the  License, or (at your
  *  option) any later version.
  *
  */

 #include <linux/clk.h>
 #include <linux/clk-provider.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/platform_device.h>
 #include <linux/mfd/wm831x/core.h>

 struct wm831x_clk {
 	struct wm831x *wm831x;
 	struct clk_hw xtal_hw;
 	struct clk_hw fll_hw;
 	struct clk_hw clkout_hw;
 	struct clk *xtal;
 	struct clk *fll;
 	struct clk *clkout;
 	bool xtal_ena;
 };

 static int wm831x_xtal_is_prepared(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  xtal_hw);

 	return clkdata->xtal_ena;
 }

 static unsigned long wm831x_xtal_recalc_rate(struct clk_hw *hw,
 					     unsigned long parent_rate)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  xtal_hw);

 	if (clkdata->xtal_ena)
 		return 32768;
 	else
 		return 0;
 }

 static const struct clk_ops wm831x_xtal_ops = {
 	.is_prepared = wm831x_xtal_is_prepared,
 	.recalc_rate = wm831x_xtal_recalc_rate,
 };

 static struct clk_init_data wm831x_xtal_init = {
 	.name = "xtal",
 	.ops = &wm831x_xtal_ops,
 	.flags = CLK_IS_ROOT,
 };

 static const unsigned long wm831x_fll_auto_rates[] = {
 	 2048000,
 	11289600,
 	12000000,
 	12288000,
 	19200000,
 	22579600,
 	24000000,
 	24576000,
 };

 static int wm831x_fll_is_prepared(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_1);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read FLL_CONTROL_1: %d\n",
 			ret);
 		return true;
 	}

 	return (ret & WM831X_FLL_ENA) != 0;
 }

 static int wm831x_fll_prepare(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1,
 			      WM831X_FLL_ENA, WM831X_FLL_ENA);
 	if (ret != 0)
 		dev_crit(wm831x->dev, "Failed to enable FLL: %d\n", ret);

 	usleep_range(2000, 2000);

 	return ret;
 }

 static void wm831x_fll_unprepare(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1, WM831X_FLL_ENA, 0);
 	if (ret != 0)
 		dev_crit(wm831x->dev, "Failed to disable FLL: %d\n", ret);
 }

 static unsigned long wm831x_fll_recalc_rate(struct clk_hw *hw,
 					    unsigned long parent_rate)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
 			ret);
 		return 0;
 	}

 	if (ret & WM831X_FLL_AUTO)
 		return wm831x_fll_auto_rates[ret & WM831X_FLL_AUTO_FREQ_MASK];

 	dev_err(wm831x->dev, "FLL only supported in AUTO mode\n");

 	return 0;
 }

 static long wm831x_fll_round_rate(struct clk_hw *hw, unsigned long rate,
 				  unsigned long *unused)
 {
 	int best = 0;
 	int i;

 	for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++)
 		if (abs(wm831x_fll_auto_rates[i] - rate) <
 		    abs(wm831x_fll_auto_rates[best] - rate))
 			best = i;

 	return wm831x_fll_auto_rates[best];
 }

 static int wm831x_fll_set_rate(struct clk_hw *hw, unsigned long rate,
 			       unsigned long parent_rate)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int i;

 	for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++)
 		if (wm831x_fll_auto_rates[i] == rate)
 			break;
 	if (i == ARRAY_SIZE(wm831x_fll_auto_rates))
 		return -EINVAL;

 	if (wm831x_fll_is_prepared(hw))
 		return -EPERM;

 	return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_2,
 			       WM831X_FLL_AUTO_FREQ_MASK, i);
 }

 static const char *wm831x_fll_parents[] = {
 	"xtal",
 	"clkin",
 };

 static u8 wm831x_fll_get_parent(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  fll_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	/* AUTO mode is always clocked from the crystal */
 	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
 			ret);
 		return 0;
 	}

 	if (ret & WM831X_FLL_AUTO)
 		return 0;

 	ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_5);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read FLL_CONTROL_5: %d\n",
 			ret);
 		return 0;
 	}

 	switch (ret & WM831X_FLL_CLK_SRC_MASK) {
 	case 0:
 		return 0;
 	case 1:
 		return 1;
 	default:
 		dev_err(wm831x->dev, "Unsupported FLL clock source %d\n",
 			ret & WM831X_FLL_CLK_SRC_MASK);
 		return 0;
 	}
 }

 static const struct clk_ops wm831x_fll_ops = {
 	.is_prepared = wm831x_fll_is_prepared,
 	.prepare = wm831x_fll_prepare,
 	.unprepare = wm831x_fll_unprepare,
 	.round_rate = wm831x_fll_round_rate,
 	.recalc_rate = wm831x_fll_recalc_rate,
 	.set_rate = wm831x_fll_set_rate,
 	.get_parent = wm831x_fll_get_parent,
 };

 static struct clk_init_data wm831x_fll_init = {
 	.name = "fll",
 	.ops = &wm831x_fll_ops,
 	.parent_names = wm831x_fll_parents,
 	.num_parents = ARRAY_SIZE(wm831x_fll_parents),
 	.flags = CLK_SET_RATE_GATE,
 };

 static int wm831x_clkout_is_prepared(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  clkout_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n",
 			ret);
 		return true;
 	}

 	return (ret & WM831X_CLKOUT_ENA) != 0;
 }

 static int wm831x_clkout_prepare(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  clkout_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_unlock(wm831x);
 	if (ret != 0) {
 		dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret);
 		return ret;
 	}

 	ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
 			      WM831X_CLKOUT_ENA, WM831X_CLKOUT_ENA);
 	if (ret != 0)
 		dev_crit(wm831x->dev, "Failed to enable CLKOUT: %d\n", ret);

 	wm831x_reg_lock(wm831x);

 	return ret;
 }

 static void wm831x_clkout_unprepare(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  clkout_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_unlock(wm831x);
 	if (ret != 0) {
 		dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret);
 		return;
 	}

 	ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
 			      WM831X_CLKOUT_ENA, 0);
 	if (ret != 0)
 		dev_crit(wm831x->dev, "Failed to disable CLKOUT: %d\n", ret);

 	wm831x_reg_lock(wm831x);
 }

 static const char *wm831x_clkout_parents[] = {
 	"fll",
 	"xtal",
 };

 static u8 wm831x_clkout_get_parent(struct clk_hw *hw)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  clkout_hw);
 	struct wm831x *wm831x = clkdata->wm831x;
 	int ret;

 	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n",
 			ret);
 		return 0;
 	}

 	if (ret & WM831X_CLKOUT_SRC)
 		return 1;
 	else
 		return 0;
 }

 static int wm831x_clkout_set_parent(struct clk_hw *hw, u8 parent)
 {
 	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
 						  clkout_hw);
 	struct wm831x *wm831x = clkdata->wm831x;

 	return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
 			       WM831X_CLKOUT_SRC,
 			       parent << WM831X_CLKOUT_SRC_SHIFT);
 }

 static const struct clk_ops wm831x_clkout_ops = {
 	.is_prepared = wm831x_clkout_is_prepared,
 	.prepare = wm831x_clkout_prepare,
 	.unprepare = wm831x_clkout_unprepare,
 	.get_parent = wm831x_clkout_get_parent,
 	.set_parent = wm831x_clkout_set_parent,
 };

 static struct clk_init_data wm831x_clkout_init = {
 	.name = "clkout",
 	.ops = &wm831x_clkout_ops,
 	.parent_names = wm831x_clkout_parents,
 	.num_parents = ARRAY_SIZE(wm831x_clkout_parents),
 	.flags = CLK_SET_RATE_PARENT,
 };

 static int wm831x_clk_probe(struct platform_device *pdev)
 {
 	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
 	struct wm831x_clk *clkdata;
 	int ret;

 	clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
 	if (!clkdata)
 		return -ENOMEM;

 	clkdata->wm831x = wm831x;

 	/* XTAL_ENA can only be set via OTP/InstantConfig so just read once */
 	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
 	if (ret < 0) {
 		dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
 			ret);
 		return ret;
 	}
 	clkdata->xtal_ena = ret & WM831X_XTAL_ENA;

 	clkdata->xtal_hw.init = &wm831x_xtal_init;
 	clkdata->xtal = devm_clk_register(&pdev->dev, &clkdata->xtal_hw);
 	if (IS_ERR(clkdata->xtal))
 		return PTR_ERR(clkdata->xtal);

 	clkdata->fll_hw.init = &wm831x_fll_init;
 	clkdata->fll = devm_clk_register(&pdev->dev, &clkdata->fll_hw);
 	if (IS_ERR(clkdata->fll))
 		return PTR_ERR(clkdata->fll);

 	clkdata->clkout_hw.init = &wm831x_clkout_init;
 	clkdata->clkout = devm_clk_register(&pdev->dev, &clkdata->clkout_hw);
 	if (IS_ERR(clkdata->clkout))
 		return PTR_ERR(clkdata->clkout);

 	platform_set_drvdata(pdev, clkdata);

 	return 0;
 }

 static struct platform_driver wm831x_clk_driver = {
 	.probe = wm831x_clk_probe,
 	.driver		= {
 		.name	= "wm831x-clk",
 		.owner	= THIS_MODULE,
 	},
 };

 module_platform_driver(wm831x_clk_driver);

 /* Module information */
 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 MODULE_DESCRIPTION("WM831x clock driver");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("platform:wm831x-clk");
	/*
	* WM831x clock control
	*
	* Copyright 2011-2 Wolfson Microelectronics PLC.
	*
	* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License as published by the
	* Free Software Foundation; either version 2 of the License, or (at your
	* option) any later version.
	*
	*/

	#include <linux/clk.h>
	#include <linux/clk-provider.h>
	#include <linux/delay.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/platform_device.h>
	#include <linux/mfd/wm831x/core.h>

	struct wm831x_clk {
	struct wm831x *wm831x;
	struct clk_hw xtal_hw;
	struct clk_hw fll_hw;
	struct clk_hw clkout_hw;
	struct clk *xtal;
	struct clk *fll;
	struct clk *clkout;
	bool xtal_ena;
	};

	static int wm831x_xtal_is_prepared(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	xtal_hw);

	return clkdata->xtal_ena;
	}

	static unsigned long wm831x_xtal_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	xtal_hw);

	if (clkdata->xtal_ena)
	return 32768;
	else
	return 0;
	}

	static const struct clk_ops wm831x_xtal_ops = {
	.is_prepared = wm831x_xtal_is_prepared,
	.recalc_rate = wm831x_xtal_recalc_rate,
	};

	static struct clk_init_data wm831x_xtal_init = {
	.name = "xtal",
	.ops = &wm831x_xtal_ops,
	.flags = CLK_IS_ROOT,
	};

	static const unsigned long wm831x_fll_auto_rates[] = {
	2048000,
	11289600,
	12000000,
	12288000,
	19200000,
	22579600,
	24000000,
	24576000,
	};

	static int wm831x_fll_is_prepared(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_1);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read FLL_CONTROL_1: %d\n",
	ret);
	return true;
	}

	return (ret & WM831X_FLL_ENA) != 0;
	}

	static int wm831x_fll_prepare(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1,
	WM831X_FLL_ENA, WM831X_FLL_ENA);
	if (ret != 0)
	dev_crit(wm831x->dev, "Failed to enable FLL: %d\n", ret);

	usleep_range(2000, 2000);

	return ret;
	}

	static void wm831x_fll_unprepare(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_set_bits(wm831x, WM831X_FLL_CONTROL_1, WM831X_FLL_ENA, 0);
	if (ret != 0)
	dev_crit(wm831x->dev, "Failed to disable FLL: %d\n", ret);
	}

	static unsigned long wm831x_fll_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
	ret);
	return 0;
	}

	if (ret & WM831X_FLL_AUTO)
	return wm831x_fll_auto_rates[ret & WM831X_FLL_AUTO_FREQ_MASK];

	dev_err(wm831x->dev, "FLL only supported in AUTO mode\n");

	return 0;
	}

	static long wm831x_fll_round_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long *unused)
	{
	int best = 0;
	int i;

	for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++)
	if (abs(wm831x_fll_auto_rates[i] - rate) <
	abs(wm831x_fll_auto_rates[best] - rate))
	best = i;

	return wm831x_fll_auto_rates[best];
	}

	static int wm831x_fll_set_rate(struct clk_hw *hw, unsigned long rate,
	unsigned long parent_rate)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int i;

	for (i = 0; i < ARRAY_SIZE(wm831x_fll_auto_rates); i++)
	if (wm831x_fll_auto_rates[i] == rate)
	break;
	if (i == ARRAY_SIZE(wm831x_fll_auto_rates))
	return -EINVAL;

	if (wm831x_fll_is_prepared(hw))
	return -EPERM;

	return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_2,
	WM831X_FLL_AUTO_FREQ_MASK, i);
	}

	static const char *wm831x_fll_parents[] = {
	"xtal",
	"clkin",
	};

	static u8 wm831x_fll_get_parent(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	fll_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	/* AUTO mode is always clocked from the crystal */
	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
	ret);
	return 0;
	}

	if (ret & WM831X_FLL_AUTO)
	return 0;

	ret = wm831x_reg_read(wm831x, WM831X_FLL_CONTROL_5);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read FLL_CONTROL_5: %d\n",
	ret);
	return 0;
	}

	switch (ret & WM831X_FLL_CLK_SRC_MASK) {
	case 0:
	return 0;
	case 1:
	return 1;
	default:
	dev_err(wm831x->dev, "Unsupported FLL clock source %d\n",
	ret & WM831X_FLL_CLK_SRC_MASK);
	return 0;
	}
	}

	static const struct clk_ops wm831x_fll_ops = {
	.is_prepared = wm831x_fll_is_prepared,
	.prepare = wm831x_fll_prepare,
	.unprepare = wm831x_fll_unprepare,
	.round_rate = wm831x_fll_round_rate,
	.recalc_rate = wm831x_fll_recalc_rate,
	.set_rate = wm831x_fll_set_rate,
	.get_parent = wm831x_fll_get_parent,
	};

	static struct clk_init_data wm831x_fll_init = {
	.name = "fll",
	.ops = &wm831x_fll_ops,
	.parent_names = wm831x_fll_parents,
	.num_parents = ARRAY_SIZE(wm831x_fll_parents),
	.flags = CLK_SET_RATE_GATE,
	};

	static int wm831x_clkout_is_prepared(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	clkout_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n",
	ret);
	return true;
	}

	return (ret & WM831X_CLKOUT_ENA) != 0;
	}

	static int wm831x_clkout_prepare(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	clkout_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_unlock(wm831x);
	if (ret != 0) {
	dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret);
	return ret;
	}

	ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
	WM831X_CLKOUT_ENA, WM831X_CLKOUT_ENA);
	if (ret != 0)
	dev_crit(wm831x->dev, "Failed to enable CLKOUT: %d\n", ret);

	wm831x_reg_lock(wm831x);

	return ret;
	}

	static void wm831x_clkout_unprepare(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	clkout_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_unlock(wm831x);
	if (ret != 0) {
	dev_crit(wm831x->dev, "Failed to lock registers: %d\n", ret);
	return;
	}

	ret = wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
	WM831X_CLKOUT_ENA, 0);
	if (ret != 0)
	dev_crit(wm831x->dev, "Failed to disable CLKOUT: %d\n", ret);

	wm831x_reg_lock(wm831x);
	}

	static const char *wm831x_clkout_parents[] = {
	"fll",
	"xtal",
	};

	static u8 wm831x_clkout_get_parent(struct clk_hw *hw)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	clkout_hw);
	struct wm831x *wm831x = clkdata->wm831x;
	int ret;

	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_1);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_1: %d\n",
	ret);
	return 0;
	}

	if (ret & WM831X_CLKOUT_SRC)
	return 1;
	else
	return 0;
	}

	static int wm831x_clkout_set_parent(struct clk_hw *hw, u8 parent)
	{
	struct wm831x_clk *clkdata = container_of(hw, struct wm831x_clk,
	clkout_hw);
	struct wm831x *wm831x = clkdata->wm831x;

	return wm831x_set_bits(wm831x, WM831X_CLOCK_CONTROL_1,
	WM831X_CLKOUT_SRC,
	parent << WM831X_CLKOUT_SRC_SHIFT);
	}

	static const struct clk_ops wm831x_clkout_ops = {
	.is_prepared = wm831x_clkout_is_prepared,
	.prepare = wm831x_clkout_prepare,
	.unprepare = wm831x_clkout_unprepare,
	.get_parent = wm831x_clkout_get_parent,
	.set_parent = wm831x_clkout_set_parent,
	};

	static struct clk_init_data wm831x_clkout_init = {
	.name = "clkout",
	.ops = &wm831x_clkout_ops,
	.parent_names = wm831x_clkout_parents,
	.num_parents = ARRAY_SIZE(wm831x_clkout_parents),
	.flags = CLK_SET_RATE_PARENT,
	};

	static int wm831x_clk_probe(struct platform_device *pdev)
	{
	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
	struct wm831x_clk *clkdata;
	int ret;

	clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
	if (!clkdata)
	return -ENOMEM;

	clkdata->wm831x = wm831x;

	/* XTAL_ENA can only be set via OTP/InstantConfig so just read once */
	ret = wm831x_reg_read(wm831x, WM831X_CLOCK_CONTROL_2);
	if (ret < 0) {
	dev_err(wm831x->dev, "Unable to read CLOCK_CONTROL_2: %d\n",
	ret);
	return ret;
	}
	clkdata->xtal_ena = ret & WM831X_XTAL_ENA;

	clkdata->xtal_hw.init = &wm831x_xtal_init;
	clkdata->xtal = devm_clk_register(&pdev->dev, &clkdata->xtal_hw);
	if (IS_ERR(clkdata->xtal))
	return PTR_ERR(clkdata->xtal);

	clkdata->fll_hw.init = &wm831x_fll_init;
	clkdata->fll = devm_clk_register(&pdev->dev, &clkdata->fll_hw);
	if (IS_ERR(clkdata->fll))
	return PTR_ERR(clkdata->fll);

	clkdata->clkout_hw.init = &wm831x_clkout_init;
	clkdata->clkout = devm_clk_register(&pdev->dev, &clkdata->clkout_hw);
	if (IS_ERR(clkdata->clkout))
	return PTR_ERR(clkdata->clkout);

	platform_set_drvdata(pdev, clkdata);

	return 0;
	}

	static struct platform_driver wm831x_clk_driver = {
	.probe = wm831x_clk_probe,
	.driver = {
	.name = "wm831x-clk",
	.owner = THIS_MODULE,
	},
	};

	module_platform_driver(wm831x_clk_driver);

	/* Module information */
	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
	MODULE_DESCRIPTION("WM831x clock driver");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("platform:wm831x-clk");