[linux-2.6-block.git] / drivers / clk / at91 / clk-system.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/of_address.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of_irq.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/sched.h>

#include "pmc.h"

#define SYSTEM_MAX_ID		31

#define SYSTEM_MAX_NAME_SZ	32

#define to_clk_system(hw) container_of(hw, struct clk_system, hw)
struct clk_system {
	struct clk_hw hw;
	struct at91_pmc *pmc;
	unsigned int irq;
	wait_queue_head_t wait;
	u8 id;
};

static inline int is_pck(int id)
{
	return (id >= 8) && (id <= 15);
}
static irqreturn_t clk_system_irq_handler(int irq, void *dev_id)
{
	struct clk_system *sys = (struct clk_system *)dev_id;

	wake_up(&sys->wait);
	disable_irq_nosync(sys->irq);

	return IRQ_HANDLED;
}

static int clk_system_prepare(struct clk_hw *hw)
{
	struct clk_system *sys = to_clk_system(hw);
	struct at91_pmc *pmc = sys->pmc;
	u32 mask = 1 << sys->id;

	pmc_write(pmc, AT91_PMC_SCER, mask);

	if (!is_pck(sys->id))
		return 0;

	while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) {
		if (sys->irq) {
			enable_irq(sys->irq);
			wait_event(sys->wait,
				   pmc_read(pmc, AT91_PMC_SR) & mask);
		} else
			cpu_relax();
	}
	return 0;
}

static void clk_system_unprepare(struct clk_hw *hw)
{
	struct clk_system *sys = to_clk_system(hw);
	struct at91_pmc *pmc = sys->pmc;

	pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id);
}

static int clk_system_is_prepared(struct clk_hw *hw)
{
	struct clk_system *sys = to_clk_system(hw);
	struct at91_pmc *pmc = sys->pmc;

	if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)))
		return 0;

	if (!is_pck(sys->id))
		return 1;

	return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id));
}

static const struct clk_ops system_ops = {
	.prepare = clk_system_prepare,
	.unprepare = clk_system_unprepare,
	.is_prepared = clk_system_is_prepared,
};

static struct clk * __init
at91_clk_register_system(struct at91_pmc *pmc, const char *name,
			 const char *parent_name, u8 id, int irq)
{
	struct clk_system *sys;
	struct clk *clk = NULL;
	struct clk_init_data init;
	int ret;

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

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

	init.name = name;
	init.ops = &system_ops;
	init.parent_names = &parent_name;
	init.num_parents = 1;
	init.flags = CLK_SET_RATE_PARENT;

	sys->id = id;
	sys->hw.init = &init;
	sys->pmc = pmc;
	sys->irq = irq;
	if (irq) {
		init_waitqueue_head(&sys->wait);
		irq_set_status_flags(sys->irq, IRQ_NOAUTOEN);
		ret = request_irq(sys->irq, clk_system_irq_handler,
				IRQF_TRIGGER_HIGH, name, sys);
		if (ret) {
			kfree(sys);
			return ERR_PTR(ret);
		}
	}

	clk = clk_register(NULL, &sys->hw);
	if (IS_ERR(clk)) {
		free_irq(sys->irq, sys);
		kfree(sys);
	}

	return clk;
}

static void __init
of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
{
	int num;
	int irq = 0;
	u32 id;
	struct clk *clk;
	const char *name;
	struct device_node *sysclknp;
	const char *parent_name;

	num = of_get_child_count(np);
	if (num > (SYSTEM_MAX_ID + 1))
		return;

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

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

		if (is_pck(id))
			irq = irq_of_parse_and_map(sysclknp, 0);

		parent_name = of_clk_get_parent_name(sysclknp, 0);

		clk = at91_clk_register_system(pmc, name, parent_name, id, irq);
		if (IS_ERR(clk))
			continue;

		of_clk_add_provider(sysclknp, of_clk_src_simple_get, clk);
	}
}

void __init of_at91rm9200_clk_sys_setup(struct device_node *np,
					struct at91_pmc *pmc)
{
	of_at91_clk_sys_setup(np, pmc);
}
Commit	Line	Data
5fba62ea 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>
	14	#include <linux/of.h>
	15	#include <linux/of_address.h>
	16	#include <linux/io.h>
cce6db80 JJH	17	#include <linux/irq.h>
	18	#include <linux/of_irq.h>
	19	#include <linux/interrupt.h>
	20	#include <linux/wait.h>
	21	#include <linux/sched.h>
5fba62ea BB	22
	23	#include "pmc.h"
	24
	25	#define SYSTEM_MAX_ID 31
	26
	27	#define SYSTEM_MAX_NAME_SZ 32
	28
	29	#define to_clk_system(hw) container_of(hw, struct clk_system, hw)
	30	struct clk_system {
	31	struct clk_hw hw;
	32	struct at91_pmc *pmc;
cce6db80 JJH	33	unsigned int irq;
cce6db80 JJH	34	wait_queue_head_t wait;
5fba62ea BB	35	u8 id;
	36	};
	37
cce6db80 JJH	38	static inline int is_pck(int id)
	39	{
	40	return (id >= 8) && (id <= 15);
	41	}
	42	static irqreturn_t clk_system_irq_handler(int irq, void *dev_id)
	43	{
	44	struct clk_system sys = (struct clk_system )dev_id;
	45
	46	wake_up(&sys->wait);
	47	disable_irq_nosync(sys->irq);
	48
	49	return IRQ_HANDLED;
	50	}
	51
	52	static int clk_system_prepare(struct clk_hw *hw)
5fba62ea BB	53	{
	54	struct clk_system *sys = to_clk_system(hw);
	55	struct at91_pmc *pmc = sys->pmc;
cce6db80	56	u32 mask = 1 << sys->id;
5fba62ea	57
cce6db80 JJH	58	pmc_write(pmc, AT91_PMC_SCER, mask);
	59
	60	if (!is_pck(sys->id))
	61	return 0;
	62
	63	while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) {
	64	if (sys->irq) {
	65	enable_irq(sys->irq);
	66	wait_event(sys->wait,
	67	pmc_read(pmc, AT91_PMC_SR) & mask);
	68	} else
	69	cpu_relax();
	70	}
5fba62ea BB	71	return 0;
	72	}
	73
cce6db80	74	static void clk_system_unprepare(struct clk_hw *hw)
5fba62ea BB	75	{
	76	struct clk_system *sys = to_clk_system(hw);
	77	struct at91_pmc *pmc = sys->pmc;
	78
	79	pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id);
	80	}
	81
cce6db80	82	static int clk_system_is_prepared(struct clk_hw *hw)
5fba62ea BB	83	{
	84	struct clk_system *sys = to_clk_system(hw);
	85	struct at91_pmc *pmc = sys->pmc;
	86
cce6db80 JJH	87	if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)))
	88	return 0;
	89
	90	if (!is_pck(sys->id))
	91	return 1;
	92
	93	return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id));
5fba62ea BB	94	}
	95
	96	static const struct clk_ops system_ops = {
cce6db80 JJH	97	.prepare = clk_system_prepare,
	98	.unprepare = clk_system_unprepare,
	99	.is_prepared = clk_system_is_prepared,
5fba62ea BB	100	};
	101
	102	static struct clk * __init
	103	at91_clk_register_system(struct at91_pmc pmc, const char name,
cce6db80	104	const char *parent_name, u8 id, int irq)
5fba62ea BB	105	{
	106	struct clk_system *sys;
	107	struct clk *clk = NULL;
	108	struct clk_init_data init;
cce6db80	109	int ret;
5fba62ea BB	110
	111	if (!parent_name \|\| id > SYSTEM_MAX_ID)
	112	return ERR_PTR(-EINVAL);
	113
	114	sys = kzalloc(sizeof(*sys), GFP_KERNEL);
	115	if (!sys)
	116	return ERR_PTR(-ENOMEM);
	117
	118	init.name = name;
	119	init.ops = &system_ops;
	120	init.parent_names = &parent_name;
	121	init.num_parents = 1;
b736bcb3	122	init.flags = CLK_SET_RATE_PARENT;
5fba62ea BB	123
	124	sys->id = id;
	125	sys->hw.init = &init;
	126	sys->pmc = pmc;
cce6db80 JJH	127	sys->irq = irq;
	128	if (irq) {
	129	init_waitqueue_head(&sys->wait);
	130	irq_set_status_flags(sys->irq, IRQ_NOAUTOEN);
	131	ret = request_irq(sys->irq, clk_system_irq_handler,
	132	IRQF_TRIGGER_HIGH, name, sys);
c76a024e DD	133	if (ret) {
c76a024e DD	134	kfree(sys);
cce6db80	135	return ERR_PTR(ret);
c76a024e	136	}
cce6db80	137	}
5fba62ea BB	138
5fba62ea BB	139	clk = clk_register(NULL, &sys->hw);
c76a024e DD	140	if (IS_ERR(clk)) {
c76a024e DD	141	free_irq(sys->irq, sys);
5fba62ea	142	kfree(sys);
c76a024e	143	}
5fba62ea BB	144
	145	return clk;
	146	}
	147
	148	static void __init
	149	of_at91_clk_sys_setup(struct device_node np, struct at91_pmc pmc)
	150	{
	151	int num;
cce6db80	152	int irq = 0;
5fba62ea BB	153	u32 id;
	154	struct clk *clk;
	155	const char *name;
	156	struct device_node *sysclknp;
	157	const char *parent_name;
	158
	159	num = of_get_child_count(np);
	160	if (num > (SYSTEM_MAX_ID + 1))
	161	return;
	162
	163	for_each_child_of_node(np, sysclknp) {
	164	if (of_property_read_u32(sysclknp, "reg", &id))
	165	continue;
	166
	167	if (of_property_read_string(np, "clock-output-names", &name))
	168	name = sysclknp->name;
	169
cce6db80 JJH	170	if (is_pck(id))
	171	irq = irq_of_parse_and_map(sysclknp, 0);
	172
5fba62ea BB	173	parent_name = of_clk_get_parent_name(sysclknp, 0);
5fba62ea BB	174
cce6db80	175	clk = at91_clk_register_system(pmc, name, parent_name, id, irq);
5fba62ea BB	176	if (IS_ERR(clk))
	177	continue;
	178
	179	of_clk_add_provider(sysclknp, of_clk_src_simple_get, clk);
	180	}
	181	}
	182
	183	void __init of_at91rm9200_clk_sys_setup(struct device_node *np,
	184	struct at91_pmc *pmc)
	185	{
	186	of_at91_clk_sys_setup(np, pmc);
	187	}