[deliverable/linux.git] / drivers / clk / at91 / clk-utmi.c

/*
 *  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 UTMI_FIXED_MUL		40

struct clk_utmi {
	struct clk_hw hw;
	struct regmap *regmap;
};

#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)

static inline bool clk_utmi_ready(struct regmap *regmap)
{
	unsigned int status;

	regmap_read(regmap, AT91_PMC_SR, &status);

	return status & AT91_PMC_LOCKU;
}

static int clk_utmi_prepare(struct clk_hw *hw)
{
	struct clk_utmi *utmi = to_clk_utmi(hw);
	unsigned int uckr = AT91_PMC_UPLLEN | AT91_PMC_UPLLCOUNT |
			    AT91_PMC_BIASEN;

	regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, uckr, uckr);

	while (!clk_utmi_ready(utmi->regmap))
		cpu_relax();

	return 0;
}

static int clk_utmi_is_prepared(struct clk_hw *hw)
{
	struct clk_utmi *utmi = to_clk_utmi(hw);

	return clk_utmi_ready(utmi->regmap);
}

static void clk_utmi_unprepare(struct clk_hw *hw)
{
	struct clk_utmi *utmi = to_clk_utmi(hw);

	regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0);
}

static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
					  unsigned long parent_rate)
{
	/* UTMI clk is a fixed clk multiplier */
	return parent_rate * UTMI_FIXED_MUL;
}

static const struct clk_ops utmi_ops = {
	.prepare = clk_utmi_prepare,
	.unprepare = clk_utmi_unprepare,
	.is_prepared = clk_utmi_is_prepared,
	.recalc_rate = clk_utmi_recalc_rate,
};

static struct clk * __init
at91_clk_register_utmi(struct regmap *regmap,
		       const char *name, const char *parent_name)
{
	struct clk_utmi *utmi;
	struct clk *clk = NULL;
	struct clk_init_data init;

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

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

	utmi->hw.init = &init;
	utmi->regmap = regmap;

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

	return clk;
}

static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np)
{
	struct clk *clk;
	const char *parent_name;
	const char *name = np->name;
	struct regmap *regmap;

	parent_name = of_clk_get_parent_name(np, 0);

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

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

	clk = at91_clk_register_utmi(regmap, name, parent_name);
	if (IS_ERR(clk))
		return;

	of_clk_add_provider(np, of_clk_src_simple_get, clk);
	return;
}
CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi",
	       of_at91sam9x5_clk_utmi_setup);
Commit	Line	Data
f090fb37 BB	1	/*
	2	* Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	*/
	10
	11	#include <linux/clk-provider.h>
	12	#include <linux/clkdev.h>
	13	#include <linux/clk/at91_pmc.h>
f090fb37	14	#include <linux/of.h>
1bdf0232 BB	15	#include <linux/mfd/syscon.h>
1bdf0232 BB	16	#include <linux/regmap.h>
f090fb37 BB	17
	18	#include "pmc.h"
	19
	20	#define UTMI_FIXED_MUL 40
	21
	22	struct clk_utmi {
	23	struct clk_hw hw;
1bdf0232	24	struct regmap *regmap;
f090fb37 BB	25	};
	26
	27	#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
	28
1bdf0232 BB	29	static inline bool clk_utmi_ready(struct regmap *regmap)
	30	{
	31	unsigned int status;
	32
	33	regmap_read(regmap, AT91_PMC_SR, &status);
	34
	35	return status & AT91_PMC_LOCKU;
	36	}
	37
f090fb37 BB	38	static int clk_utmi_prepare(struct clk_hw *hw)
	39	{
	40	struct clk_utmi *utmi = to_clk_utmi(hw);
1bdf0232 BB	41	unsigned int uckr = AT91_PMC_UPLLEN \| AT91_PMC_UPLLCOUNT \|
1bdf0232 BB	42	AT91_PMC_BIASEN;
f090fb37	43
1bdf0232	44	regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, uckr, uckr);
f090fb37	45
99a81706 AB	46	while (!clk_utmi_ready(utmi->regmap))
99a81706 AB	47	cpu_relax();
f090fb37 BB	48
	49	return 0;
	50	}
	51
	52	static int clk_utmi_is_prepared(struct clk_hw *hw)
	53	{
	54	struct clk_utmi *utmi = to_clk_utmi(hw);
f090fb37	55
1bdf0232	56	return clk_utmi_ready(utmi->regmap);
f090fb37 BB	57	}
	58
	59	static void clk_utmi_unprepare(struct clk_hw *hw)
	60	{
	61	struct clk_utmi *utmi = to_clk_utmi(hw);
f090fb37	62
1bdf0232	63	regmap_update_bits(utmi->regmap, AT91_CKGR_UCKR, AT91_PMC_UPLLEN, 0);
f090fb37 BB	64	}
	65
	66	static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
	67	unsigned long parent_rate)
	68	{
	69	/* UTMI clk is a fixed clk multiplier */
	70	return parent_rate * UTMI_FIXED_MUL;
	71	}
	72
	73	static const struct clk_ops utmi_ops = {
	74	.prepare = clk_utmi_prepare,
	75	.unprepare = clk_utmi_unprepare,
	76	.is_prepared = clk_utmi_is_prepared,
	77	.recalc_rate = clk_utmi_recalc_rate,
	78	};
	79
	80	static struct clk * __init
99a81706	81	at91_clk_register_utmi(struct regmap *regmap,
f090fb37 BB	82	const char name, const char parent_name)
f090fb37 BB	83	{
f090fb37 BB	84	struct clk_utmi *utmi;
	85	struct clk *clk = NULL;
	86	struct clk_init_data init;
	87
	88	utmi = kzalloc(sizeof(*utmi), GFP_KERNEL);
	89	if (!utmi)
	90	return ERR_PTR(-ENOMEM);
	91
	92	init.name = name;
	93	init.ops = &utmi_ops;
	94	init.parent_names = parent_name ? &parent_name : NULL;
	95	init.num_parents = parent_name ? 1 : 0;
	96	init.flags = CLK_SET_RATE_GATE;
	97
	98	utmi->hw.init = &init;
1bdf0232	99	utmi->regmap = regmap;
f090fb37 BB	100
f090fb37 BB	101	clk = clk_register(NULL, &utmi->hw);
99a81706	102	if (IS_ERR(clk))
f090fb37 BB	103	kfree(utmi);
	104
	105	return clk;
	106	}
	107
1bdf0232	108	static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np)
f090fb37	109	{
f090fb37 BB	110	struct clk *clk;
	111	const char *parent_name;
	112	const char *name = np->name;
1bdf0232	113	struct regmap *regmap;
f090fb37 BB	114
	115	parent_name = of_clk_get_parent_name(np, 0);
	116
	117	of_property_read_string(np, "clock-output-names", &name);
	118
1bdf0232 BB	119	regmap = syscon_node_to_regmap(of_get_parent(np));
	120	if (IS_ERR(regmap))
	121	return;
	122
99a81706	123	clk = at91_clk_register_utmi(regmap, name, parent_name);
f090fb37 BB	124	if (IS_ERR(clk))
	125	return;
	126
	127	of_clk_add_provider(np, of_clk_src_simple_get, clk);
	128	return;
	129	}
1bdf0232 BB	130	CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi",
1bdf0232 BB	131	of_at91sam9x5_clk_utmi_setup);