drivers/clk/at91/clk-peripheral.c - kernel/quantenna - Git at Google

 /*
  *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.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-provider.h>
 #include <linux/clkdev.h>
 #include <linux/clk/at91_pmc.h>
 #include <linux/of.h>
 #include <linux/mfd/syscon.h>
 #include <linux/regmap.h>

 #include "pmc.h"

 DEFINE_SPINLOCK(pmc_pcr_lock);

 #define PERIPHERAL_MAX		64

 #define PERIPHERAL_AT91RM9200	0
 #define PERIPHERAL_AT91SAM9X5	1

 #define PERIPHERAL_ID_MIN	2
 #define PERIPHERAL_ID_MAX	31
 #define PERIPHERAL_MASK(id)	(1 << ((id) & PERIPHERAL_ID_MAX))

 #define PERIPHERAL_RSHIFT_MASK	0x3
 #define PERIPHERAL_RSHIFT(val)	(((val) >> 16) & PERIPHERAL_RSHIFT_MASK)

 #define PERIPHERAL_MAX_SHIFT	3

 struct clk_peripheral {
 	struct clk_hw hw;
 	struct regmap *regmap;
 	u32 id;
 };

 #define to_clk_peripheral(hw) container_of(hw, struct clk_peripheral, hw)

 struct clk_sam9x5_peripheral {
 	struct clk_hw hw;
 	struct regmap *regmap;
 	struct clk_range range;
 	spinlock_t *lock;
 	u32 id;
 	u32 div;
 	bool auto_div;
 };

 #define to_clk_sam9x5_peripheral(hw) \
 	container_of(hw, struct clk_sam9x5_peripheral, hw)

 static int clk_peripheral_enable(struct clk_hw *hw)
 {
 	struct clk_peripheral *periph = to_clk_peripheral(hw);
 	int offset = AT91_PMC_PCER;
 	u32 id = periph->id;

 	if (id < PERIPHERAL_ID_MIN)
 		return 0;
 	if (id > PERIPHERAL_ID_MAX)
 		offset = AT91_PMC_PCER1;
 	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));

 	return 0;
 }

 static void clk_peripheral_disable(struct clk_hw *hw)
 {
 	struct clk_peripheral *periph = to_clk_peripheral(hw);
 	int offset = AT91_PMC_PCDR;
 	u32 id = periph->id;

 	if (id < PERIPHERAL_ID_MIN)
 		return;
 	if (id > PERIPHERAL_ID_MAX)
 		offset = AT91_PMC_PCDR1;
 	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));
 }

 static int clk_peripheral_is_enabled(struct clk_hw *hw)
 {
 	struct clk_peripheral *periph = to_clk_peripheral(hw);
 	int offset = AT91_PMC_PCSR;
 	unsigned int status;
 	u32 id = periph->id;

 	if (id < PERIPHERAL_ID_MIN)
 		return 1;
 	if (id > PERIPHERAL_ID_MAX)
 		offset = AT91_PMC_PCSR1;
 	regmap_read(periph->regmap, offset, &status);

 	return status & PERIPHERAL_MASK(id) ? 1 : 0;
 }

 static const struct clk_ops peripheral_ops = {
 	.enable = clk_peripheral_enable,
 	.disable = clk_peripheral_disable,
 	.is_enabled = clk_peripheral_is_enabled,
 };

 static struct clk * __init
 at91_clk_register_peripheral(struct regmap *regmap, const char *name,
 			     const char *parent_name, u32 id)
 {
 	struct clk_peripheral *periph;
 	struct clk *clk = NULL;
 	struct clk_init_data init;

 	if (!name || !parent_name || id > PERIPHERAL_ID_MAX)
 		return ERR_PTR(-EINVAL);

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

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

 	periph->id = id;
 	periph->hw.init = &init;
 	periph->regmap = regmap;

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

 	return clk;
 }

 static void clk_sam9x5_peripheral_autodiv(struct clk_sam9x5_peripheral *periph)
 {
 	struct clk_hw *parent;
 	unsigned long parent_rate;
 	int shift = 0;

 	if (!periph->auto_div)
 		return;

 	if (periph->range.max) {
 		parent = clk_hw_get_parent_by_index(&periph->hw, 0);
 		parent_rate = clk_hw_get_rate(parent);
 		if (!parent_rate)
 			return;

 		for (; shift < PERIPHERAL_MAX_SHIFT; shift++) {
 			if (parent_rate >> shift <= periph->range.max)
 				break;
 		}
 	}

 	periph->auto_div = false;
 	periph->div = shift;
 }

 static int clk_sam9x5_peripheral_enable(struct clk_hw *hw)
 {
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
 	unsigned long flags;

 	if (periph->id < PERIPHERAL_ID_MIN)
 		return 0;

 	spin_lock_irqsave(periph->lock, flags);
 	regmap_write(periph->regmap, AT91_PMC_PCR,
 		     (periph->id & AT91_PMC_PCR_PID_MASK));
 	regmap_update_bits(periph->regmap, AT91_PMC_PCR,
 			   AT91_PMC_PCR_DIV_MASK | AT91_PMC_PCR_CMD |
 			   AT91_PMC_PCR_EN,
 			   AT91_PMC_PCR_DIV(periph->div) |
 			   AT91_PMC_PCR_CMD |
 			   AT91_PMC_PCR_EN);
 	spin_unlock_irqrestore(periph->lock, flags);

 	return 0;
 }

 static void clk_sam9x5_peripheral_disable(struct clk_hw *hw)
 {
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
 	unsigned long flags;

 	if (periph->id < PERIPHERAL_ID_MIN)
 		return;

 	spin_lock_irqsave(periph->lock, flags);
 	regmap_write(periph->regmap, AT91_PMC_PCR,
 		     (periph->id & AT91_PMC_PCR_PID_MASK));
 	regmap_update_bits(periph->regmap, AT91_PMC_PCR,
 			   AT91_PMC_PCR_EN | AT91_PMC_PCR_CMD,
 			   AT91_PMC_PCR_CMD);
 	spin_unlock_irqrestore(periph->lock, flags);
 }

 static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw)
 {
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
 	unsigned long flags;
 	unsigned int status;

 	if (periph->id < PERIPHERAL_ID_MIN)
 		return 1;

 	spin_lock_irqsave(periph->lock, flags);
 	regmap_write(periph->regmap, AT91_PMC_PCR,
 		     (periph->id & AT91_PMC_PCR_PID_MASK));
 	regmap_read(periph->regmap, AT91_PMC_PCR, &status);
 	spin_unlock_irqrestore(periph->lock, flags);

 	return status & AT91_PMC_PCR_EN ? 1 : 0;
 }

 static unsigned long
 clk_sam9x5_peripheral_recalc_rate(struct clk_hw *hw,
 				  unsigned long parent_rate)
 {
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
 	unsigned long flags;
 	unsigned int status;

 	if (periph->id < PERIPHERAL_ID_MIN)
 		return parent_rate;

 	spin_lock_irqsave(periph->lock, flags);
 	regmap_write(periph->regmap, AT91_PMC_PCR,
 		     (periph->id & AT91_PMC_PCR_PID_MASK));
 	regmap_read(periph->regmap, AT91_PMC_PCR, &status);
 	spin_unlock_irqrestore(periph->lock, flags);

 	if (status & AT91_PMC_PCR_EN) {
 		periph->div = PERIPHERAL_RSHIFT(status);
 		periph->auto_div = false;
 	} else {
 		clk_sam9x5_peripheral_autodiv(periph);
 	}

 	return parent_rate >> periph->div;
 }

 static long clk_sam9x5_peripheral_round_rate(struct clk_hw *hw,
 					     unsigned long rate,
 					     unsigned long *parent_rate)
 {
 	int shift = 0;
 	unsigned long best_rate;
 	unsigned long best_diff;
 	unsigned long cur_rate = *parent_rate;
 	unsigned long cur_diff;
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);

 	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max)
 		return *parent_rate;

 	if (periph->range.max) {
 		for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
 			cur_rate = *parent_rate >> shift;
 			if (cur_rate <= periph->range.max)
 				break;
 		}
 	}

 	if (rate >= cur_rate)
 		return cur_rate;

 	best_diff = cur_rate - rate;
 	best_rate = cur_rate;
 	for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
 		cur_rate = *parent_rate >> shift;
 		if (cur_rate < rate)
 			cur_diff = rate - cur_rate;
 		else
 			cur_diff = cur_rate - rate;

 		if (cur_diff < best_diff) {
 			best_diff = cur_diff;
 			best_rate = cur_rate;
 		}

 		if (!best_diff || cur_rate < rate)
 			break;
 	}

 	return best_rate;
 }

 static int clk_sam9x5_peripheral_set_rate(struct clk_hw *hw,
 					  unsigned long rate,
 					  unsigned long parent_rate)
 {
 	int shift;
 	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
 	if (periph->id < PERIPHERAL_ID_MIN || !periph->range.max) {
 		if (parent_rate == rate)
 			return 0;
 		else
 			return -EINVAL;
 	}

 	if (periph->range.max && rate > periph->range.max)
 		return -EINVAL;

 	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
 		if (parent_rate >> shift == rate) {
 			periph->auto_div = false;
 			periph->div = shift;
 			return 0;
 		}
 	}

 	return -EINVAL;
 }

 static const struct clk_ops sam9x5_peripheral_ops = {
 	.enable = clk_sam9x5_peripheral_enable,
 	.disable = clk_sam9x5_peripheral_disable,
 	.is_enabled = clk_sam9x5_peripheral_is_enabled,
 	.recalc_rate = clk_sam9x5_peripheral_recalc_rate,
 	.round_rate = clk_sam9x5_peripheral_round_rate,
 	.set_rate = clk_sam9x5_peripheral_set_rate,
 };

 static struct clk * __init
 at91_clk_register_sam9x5_peripheral(struct regmap *regmap, spinlock_t *lock,
 				    const char *name, const char *parent_name,
 				    u32 id, const struct clk_range *range)
 {
 	struct clk_sam9x5_peripheral *periph;
 	struct clk *clk = NULL;
 	struct clk_init_data init;

 	if (!name || !parent_name)
 		return ERR_PTR(-EINVAL);

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

 	init.name = name;
 	init.ops = &sam9x5_peripheral_ops;
 	init.parent_names = (parent_name ? &parent_name : NULL);
 	init.num_parents = (parent_name ? 1 : 0);
 	init.flags = 0;

 	periph->id = id;
 	periph->hw.init = &init;
 	periph->div = 0;
 	periph->regmap = regmap;
 	periph->lock = lock;
 	periph->auto_div = true;
 	periph->range = *range;

 	clk = clk_register(NULL, &periph->hw);
 	if (IS_ERR(clk))
 		kfree(periph);
 	else
 		clk_sam9x5_peripheral_autodiv(periph);

 	return clk;
 }

 static void __init
 of_at91_clk_periph_setup(struct device_node *np, u8 type)
 {
 	int num;
 	u32 id;
 	struct clk *clk;
 	const char *parent_name;
 	const char *name;
 	struct device_node *periphclknp;
 	struct regmap *regmap;

 	parent_name = of_clk_get_parent_name(np, 0);
 	if (!parent_name)
 		return;

 	num = of_get_child_count(np);
 	if (!num || num > PERIPHERAL_MAX)
 		return;

 	regmap = syscon_node_to_regmap(of_get_parent(np));
 	if (IS_ERR(regmap))
 		return;

 	for_each_child_of_node(np, periphclknp) {
 		if (of_property_read_u32(periphclknp, "reg", &id))
 			continue;

 		if (id >= PERIPHERAL_MAX)
 			continue;

 		if (of_property_read_string(np, "clock-output-names", &name))
 			name = periphclknp->name;

 		if (type == PERIPHERAL_AT91RM9200) {
 			clk = at91_clk_register_peripheral(regmap, name,
 							   parent_name, id);
 		} else {
 			struct clk_range range = CLK_RANGE(0, 0);

 			of_at91_get_clk_range(periphclknp,
 					      "atmel,clk-output-range",
 					      &range);

 			clk = at91_clk_register_sam9x5_peripheral(regmap,
 								  &pmc_pcr_lock,
 								  name,
 								  parent_name,
 								  id, &range);
 		}

 		if (IS_ERR(clk))
 			continue;

 		of_clk_add_provider(periphclknp, of_clk_src_simple_get, clk);
 	}
 }

 static void __init of_at91rm9200_clk_periph_setup(struct device_node *np)
 {
 	of_at91_clk_periph_setup(np, PERIPHERAL_AT91RM9200);
 }
 CLK_OF_DECLARE(at91rm9200_clk_periph, "atmel,at91rm9200-clk-peripheral",
 	       of_at91rm9200_clk_periph_setup);

 static void __init of_at91sam9x5_clk_periph_setup(struct device_node *np)
 {
 	of_at91_clk_periph_setup(np, PERIPHERAL_AT91SAM9X5);
 }
 CLK_OF_DECLARE(at91sam9x5_clk_periph, "atmel,at91sam9x5-clk-peripheral",
 	       of_at91sam9x5_clk_periph_setup);
	/*
	* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.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-provider.h>
	#include <linux/clkdev.h>
	#include <linux/clk/at91_pmc.h>
	#include <linux/of.h>
	#include <linux/mfd/syscon.h>
	#include <linux/regmap.h>

	#include "pmc.h"

	DEFINE_SPINLOCK(pmc_pcr_lock);

	#define PERIPHERAL_MAX 64

	#define PERIPHERAL_AT91RM9200 0
	#define PERIPHERAL_AT91SAM9X5 1

	#define PERIPHERAL_ID_MIN 2
	#define PERIPHERAL_ID_MAX 31
	#define PERIPHERAL_MASK(id) (1 << ((id) & PERIPHERAL_ID_MAX))

	#define PERIPHERAL_RSHIFT_MASK 0x3
	#define PERIPHERAL_RSHIFT(val) (((val) >> 16) & PERIPHERAL_RSHIFT_MASK)

	#define PERIPHERAL_MAX_SHIFT 3

	struct clk_peripheral {
	struct clk_hw hw;
	struct regmap *regmap;
	u32 id;
	};

	#define to_clk_peripheral(hw) container_of(hw, struct clk_peripheral, hw)

	struct clk_sam9x5_peripheral {
	struct clk_hw hw;
	struct regmap *regmap;
	struct clk_range range;
	spinlock_t *lock;
	u32 id;
	u32 div;
	bool auto_div;
	};

	#define to_clk_sam9x5_peripheral(hw) \
	container_of(hw, struct clk_sam9x5_peripheral, hw)

	static int clk_peripheral_enable(struct clk_hw *hw)
	{
	struct clk_peripheral *periph = to_clk_peripheral(hw);
	int offset = AT91_PMC_PCER;
	u32 id = periph->id;

	if (id < PERIPHERAL_ID_MIN)
	return 0;
	if (id > PERIPHERAL_ID_MAX)
	offset = AT91_PMC_PCER1;
	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));

	return 0;
	}

	static void clk_peripheral_disable(struct clk_hw *hw)
	{
	struct clk_peripheral *periph = to_clk_peripheral(hw);
	int offset = AT91_PMC_PCDR;
	u32 id = periph->id;

	if (id < PERIPHERAL_ID_MIN)
	return;
	if (id > PERIPHERAL_ID_MAX)
	offset = AT91_PMC_PCDR1;
	regmap_write(periph->regmap, offset, PERIPHERAL_MASK(id));
	}

	static int clk_peripheral_is_enabled(struct clk_hw *hw)
	{
	struct clk_peripheral *periph = to_clk_peripheral(hw);
	int offset = AT91_PMC_PCSR;
	unsigned int status;
	u32 id = periph->id;

	if (id < PERIPHERAL_ID_MIN)
	return 1;
	if (id > PERIPHERAL_ID_MAX)
	offset = AT91_PMC_PCSR1;
	regmap_read(periph->regmap, offset, &status);

	return status & PERIPHERAL_MASK(id) ? 1 : 0;
	}

	static const struct clk_ops peripheral_ops = {
	.enable = clk_peripheral_enable,
	.disable = clk_peripheral_disable,
	.is_enabled = clk_peripheral_is_enabled,
	};

	static struct clk * __init
	at91_clk_register_peripheral(struct regmap regmap, const char name,
	const char *parent_name, u32 id)
	{
	struct clk_peripheral *periph;
	struct clk *clk = NULL;
	struct clk_init_data init;

	if (!name \|\| !parent_name \|\| id > PERIPHERAL_ID_MAX)
	return ERR_PTR(-EINVAL);

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

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

	periph->id = id;
	periph->hw.init = &init;
	periph->regmap = regmap;

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

	return clk;
	}

	static void clk_sam9x5_peripheral_autodiv(struct clk_sam9x5_peripheral *periph)
	{
	struct clk_hw *parent;
	unsigned long parent_rate;
	int shift = 0;

	if (!periph->auto_div)
	return;

	if (periph->range.max) {
	parent = clk_hw_get_parent_by_index(&periph->hw, 0);
	parent_rate = clk_hw_get_rate(parent);
	if (!parent_rate)
	return;

	for (; shift < PERIPHERAL_MAX_SHIFT; shift++) {
	if (parent_rate >> shift <= periph->range.max)
	break;
	}
	}

	periph->auto_div = false;
	periph->div = shift;
	}

	static int clk_sam9x5_peripheral_enable(struct clk_hw *hw)
	{
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
	unsigned long flags;

	if (periph->id < PERIPHERAL_ID_MIN)
	return 0;

	spin_lock_irqsave(periph->lock, flags);
	regmap_write(periph->regmap, AT91_PMC_PCR,
	(periph->id & AT91_PMC_PCR_PID_MASK));
	regmap_update_bits(periph->regmap, AT91_PMC_PCR,
	AT91_PMC_PCR_DIV_MASK \| AT91_PMC_PCR_CMD \|
	AT91_PMC_PCR_EN,
	AT91_PMC_PCR_DIV(periph->div) \|
	AT91_PMC_PCR_CMD \|
	AT91_PMC_PCR_EN);
	spin_unlock_irqrestore(periph->lock, flags);

	return 0;
	}

	static void clk_sam9x5_peripheral_disable(struct clk_hw *hw)
	{
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
	unsigned long flags;

	if (periph->id < PERIPHERAL_ID_MIN)
	return;

	spin_lock_irqsave(periph->lock, flags);
	regmap_write(periph->regmap, AT91_PMC_PCR,
	(periph->id & AT91_PMC_PCR_PID_MASK));
	regmap_update_bits(periph->regmap, AT91_PMC_PCR,
	AT91_PMC_PCR_EN \| AT91_PMC_PCR_CMD,
	AT91_PMC_PCR_CMD);
	spin_unlock_irqrestore(periph->lock, flags);
	}

	static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw)
	{
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
	unsigned long flags;
	unsigned int status;

	if (periph->id < PERIPHERAL_ID_MIN)
	return 1;

	spin_lock_irqsave(periph->lock, flags);
	regmap_write(periph->regmap, AT91_PMC_PCR,
	(periph->id & AT91_PMC_PCR_PID_MASK));
	regmap_read(periph->regmap, AT91_PMC_PCR, &status);
	spin_unlock_irqrestore(periph->lock, flags);

	return status & AT91_PMC_PCR_EN ? 1 : 0;
	}

	static unsigned long
	clk_sam9x5_peripheral_recalc_rate(struct clk_hw *hw,
	unsigned long parent_rate)
	{
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
	unsigned long flags;
	unsigned int status;

	if (periph->id < PERIPHERAL_ID_MIN)
	return parent_rate;

	spin_lock_irqsave(periph->lock, flags);
	regmap_write(periph->regmap, AT91_PMC_PCR,
	(periph->id & AT91_PMC_PCR_PID_MASK));
	regmap_read(periph->regmap, AT91_PMC_PCR, &status);
	spin_unlock_irqrestore(periph->lock, flags);

	if (status & AT91_PMC_PCR_EN) {
	periph->div = PERIPHERAL_RSHIFT(status);
	periph->auto_div = false;
	} else {
	clk_sam9x5_peripheral_autodiv(periph);
	}

	return parent_rate >> periph->div;
	}

	static long clk_sam9x5_peripheral_round_rate(struct clk_hw *hw,
	unsigned long rate,
	unsigned long *parent_rate)
	{
	int shift = 0;
	unsigned long best_rate;
	unsigned long best_diff;
	unsigned long cur_rate = *parent_rate;
	unsigned long cur_diff;
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);

	if (periph->id < PERIPHERAL_ID_MIN \|\| !periph->range.max)
	return *parent_rate;

	if (periph->range.max) {
	for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
	cur_rate = *parent_rate >> shift;
	if (cur_rate <= periph->range.max)
	break;
	}
	}

	if (rate >= cur_rate)
	return cur_rate;

	best_diff = cur_rate - rate;
	best_rate = cur_rate;
	for (; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
	cur_rate = *parent_rate >> shift;
	if (cur_rate < rate)
	cur_diff = rate - cur_rate;
	else
	cur_diff = cur_rate - rate;

	if (cur_diff < best_diff) {
	best_diff = cur_diff;
	best_rate = cur_rate;
	}

	if (!best_diff \|\| cur_rate < rate)
	break;
	}

	return best_rate;
	}

	static int clk_sam9x5_peripheral_set_rate(struct clk_hw *hw,
	unsigned long rate,
	unsigned long parent_rate)
	{
	int shift;
	struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw);
	if (periph->id < PERIPHERAL_ID_MIN \|\| !periph->range.max) {
	if (parent_rate == rate)
	return 0;
	else
	return -EINVAL;
	}

	if (periph->range.max && rate > periph->range.max)
	return -EINVAL;

	for (shift = 0; shift <= PERIPHERAL_MAX_SHIFT; shift++) {
	if (parent_rate >> shift == rate) {
	periph->auto_div = false;
	periph->div = shift;
	return 0;
	}
	}

	return -EINVAL;
	}

	static const struct clk_ops sam9x5_peripheral_ops = {
	.enable = clk_sam9x5_peripheral_enable,
	.disable = clk_sam9x5_peripheral_disable,
	.is_enabled = clk_sam9x5_peripheral_is_enabled,
	.recalc_rate = clk_sam9x5_peripheral_recalc_rate,
	.round_rate = clk_sam9x5_peripheral_round_rate,
	.set_rate = clk_sam9x5_peripheral_set_rate,
	};

	static struct clk * __init
	at91_clk_register_sam9x5_peripheral(struct regmap regmap, spinlock_t lock,
	const char name, const char parent_name,
	u32 id, const struct clk_range *range)
	{
	struct clk_sam9x5_peripheral *periph;
	struct clk *clk = NULL;
	struct clk_init_data init;

	if (!name \|\| !parent_name)
	return ERR_PTR(-EINVAL);

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

	init.name = name;
	init.ops = &sam9x5_peripheral_ops;
	init.parent_names = (parent_name ? &parent_name : NULL);
	init.num_parents = (parent_name ? 1 : 0);
	init.flags = 0;

	periph->id = id;
	periph->hw.init = &init;
	periph->div = 0;
	periph->regmap = regmap;
	periph->lock = lock;
	periph->auto_div = true;
	periph->range = *range;

	clk = clk_register(NULL, &periph->hw);
	if (IS_ERR(clk))
	kfree(periph);
	else
	clk_sam9x5_peripheral_autodiv(periph);

	return clk;
	}

	static void __init
	of_at91_clk_periph_setup(struct device_node *np, u8 type)
	{
	int num;
	u32 id;
	struct clk *clk;
	const char *parent_name;
	const char *name;
	struct device_node *periphclknp;
	struct regmap *regmap;

	parent_name = of_clk_get_parent_name(np, 0);
	if (!parent_name)
	return;

	num = of_get_child_count(np);
	if (!num \|\| num > PERIPHERAL_MAX)
	return;

	regmap = syscon_node_to_regmap(of_get_parent(np));
	if (IS_ERR(regmap))
	return;

	for_each_child_of_node(np, periphclknp) {
	if (of_property_read_u32(periphclknp, "reg", &id))
	continue;

	if (id >= PERIPHERAL_MAX)
	continue;

	if (of_property_read_string(np, "clock-output-names", &name))
	name = periphclknp->name;

	if (type == PERIPHERAL_AT91RM9200) {
	clk = at91_clk_register_peripheral(regmap, name,
	parent_name, id);
	} else {
	struct clk_range range = CLK_RANGE(0, 0);

	of_at91_get_clk_range(periphclknp,
	"atmel,clk-output-range",
	&range);

	clk = at91_clk_register_sam9x5_peripheral(regmap,
	&pmc_pcr_lock,
	name,
	parent_name,
	id, &range);
	}

	if (IS_ERR(clk))
	continue;

	of_clk_add_provider(periphclknp, of_clk_src_simple_get, clk);
	}
	}

	static void __init of_at91rm9200_clk_periph_setup(struct device_node *np)
	{
	of_at91_clk_periph_setup(np, PERIPHERAL_AT91RM9200);
	}
	CLK_OF_DECLARE(at91rm9200_clk_periph, "atmel,at91rm9200-clk-peripheral",
	of_at91rm9200_clk_periph_setup);

	static void __init of_at91sam9x5_clk_periph_setup(struct device_node *np)
	{
	of_at91_clk_periph_setup(np, PERIPHERAL_AT91SAM9X5);
	}
	CLK_OF_DECLARE(at91sam9x5_clk_periph, "atmel,at91sam9x5-clk-peripheral",
	of_at91sam9x5_clk_periph_setup);