[mirror_ubuntu-zesty-kernel.git] / arch / arm / plat-s3c / clock.c

/* linux/arch/arm/plat-s3c24xx/clock.c
 *
 * Copyright (c) 2004-2005 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * S3C24XX Core clock control support
 *
 * Based on, and code from linux/arch/arm/mach-versatile/clock.c
 **
 **  Copyright (C) 2004 ARM Limited.
 **  Written by Deep Blue Solutions Limited.
 *
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/sysdev.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/spinlock.h>
#include <linux/io.h>

#include <mach/hardware.h>
#include <asm/irq.h>

#include <plat/cpu-freq.h>

#include <plat/clock.h>
#include <plat/cpu.h>

/* clock information */

static LIST_HEAD(clocks);

/* We originally used an mutex here, but some contexts (see resume)
 * are calling functions such as clk_set_parent() with IRQs disabled
 * causing an BUG to be triggered.
 */
DEFINE_SPINLOCK(clocks_lock);

/* enable and disable calls for use with the clk struct */

static int clk_null_enable(struct clk *clk, int enable)
{
	return 0;
}

/* Clock API calls */

struct clk *clk_get(struct device *dev, const char *id)
{
	struct clk *p;
	struct clk *clk = ERR_PTR(-ENOENT);
	int idno;

	if (dev == NULL || dev->bus != &platform_bus_type)
		idno = -1;
	else
		idno = to_platform_device(dev)->id;

	spin_lock(&clocks_lock);

	list_for_each_entry(p, &clocks, list) {
		if (p->id == idno &&
		    strcmp(id, p->name) == 0 &&
		    try_module_get(p->owner)) {
			clk = p;
			break;
		}
	}

	/* check for the case where a device was supplied, but the
	 * clock that was being searched for is not device specific */

	if (IS_ERR(clk)) {
		list_for_each_entry(p, &clocks, list) {
			if (p->id == -1 && strcmp(id, p->name) == 0 &&
			    try_module_get(p->owner)) {
				clk = p;
				break;
			}
		}
	}

	spin_unlock(&clocks_lock);
	return clk;
}

void clk_put(struct clk *clk)
{
	module_put(clk->owner);
}

int clk_enable(struct clk *clk)
{
	if (IS_ERR(clk) || clk == NULL)
		return -EINVAL;

	clk_enable(clk->parent);

	spin_lock(&clocks_lock);

	if ((clk->usage++) == 0)
		(clk->enable)(clk, 1);

	spin_unlock(&clocks_lock);
	return 0;
}

void clk_disable(struct clk *clk)
{
	if (IS_ERR(clk) || clk == NULL)
		return;

	spin_lock(&clocks_lock);

	if ((--clk->usage) == 0)
		(clk->enable)(clk, 0);

	spin_unlock(&clocks_lock);
	clk_disable(clk->parent);
}


unsigned long clk_get_rate(struct clk *clk)
{
	if (IS_ERR(clk))
		return 0;

	if (clk->rate != 0)
		return clk->rate;

	if (clk->get_rate != NULL)
		return (clk->get_rate)(clk);

	if (clk->parent != NULL)
		return clk_get_rate(clk->parent);

	return clk->rate;
}

long clk_round_rate(struct clk *clk, unsigned long rate)
{
	if (!IS_ERR(clk) && clk->round_rate)
		return (clk->round_rate)(clk, rate);

	return rate;
}

int clk_set_rate(struct clk *clk, unsigned long rate)
{
	int ret;

	if (IS_ERR(clk))
		return -EINVAL;

	/* We do not default just do a clk->rate = rate as
	 * the clock may have been made this way by choice.
	 */

	WARN_ON(clk->set_rate == NULL);

	if (clk->set_rate == NULL)
		return -EINVAL;

	spin_lock(&clocks_lock);
	ret = (clk->set_rate)(clk, rate);
	spin_unlock(&clocks_lock);

	return ret;
}

struct clk *clk_get_parent(struct clk *clk)
{
	return clk->parent;
}

int clk_set_parent(struct clk *clk, struct clk *parent)
{
	int ret = 0;

	if (IS_ERR(clk))
		return -EINVAL;

	spin_lock(&clocks_lock);

	if (clk->set_parent)
		ret = (clk->set_parent)(clk, parent);

	spin_unlock(&clocks_lock);

	return ret;
}

EXPORT_SYMBOL(clk_get);
EXPORT_SYMBOL(clk_put);
EXPORT_SYMBOL(clk_enable);
EXPORT_SYMBOL(clk_disable);
EXPORT_SYMBOL(clk_get_rate);
EXPORT_SYMBOL(clk_round_rate);
EXPORT_SYMBOL(clk_set_rate);
EXPORT_SYMBOL(clk_get_parent);
EXPORT_SYMBOL(clk_set_parent);

/* base clocks */

static int clk_default_setrate(struct clk *clk, unsigned long rate)
{
	clk->rate = rate;
	return 0;
}

struct clk clk_xtal = {
	.name		= "xtal",
	.id		= -1,
	.rate		= 0,
	.parent		= NULL,
	.ctrlbit	= 0,
};

struct clk clk_ext = {
	.name		= "ext",
	.id		= -1,
};

struct clk clk_epll = {
	.name		= "epll",
	.id		= -1,
};

struct clk clk_mpll = {
	.name		= "mpll",
	.id		= -1,
	.set_rate	= clk_default_setrate,
};

struct clk clk_upll = {
	.name		= "upll",
	.id		= -1,
	.parent		= NULL,
	.ctrlbit	= 0,
};

struct clk clk_f = {
	.name		= "fclk",
	.id		= -1,
	.rate		= 0,
	.parent		= &clk_mpll,
	.ctrlbit	= 0,
	.set_rate	= clk_default_setrate,
};

struct clk clk_h = {
	.name		= "hclk",
	.id		= -1,
	.rate		= 0,
	.parent		= NULL,
	.ctrlbit	= 0,
	.set_rate	= clk_default_setrate,
};

struct clk clk_p = {
	.name		= "pclk",
	.id		= -1,
	.rate		= 0,
	.parent		= NULL,
	.ctrlbit	= 0,
	.set_rate	= clk_default_setrate,
};

struct clk clk_usb_bus = {
	.name		= "usb-bus",
	.id		= -1,
	.rate		= 0,
	.parent		= &clk_upll,
};


struct clk s3c24xx_uclk = {
	.name		= "uclk",
	.id		= -1,
};

/* initialise the clock system */

int s3c24xx_register_clock(struct clk *clk)
{
	clk->owner = THIS_MODULE;

	if (clk->enable == NULL)
		clk->enable = clk_null_enable;

	/* add to the list of available clocks */

	/* Quick check to see if this clock has already been registered. */
	BUG_ON(clk->list.prev != clk->list.next);

	spin_lock(&clocks_lock);
	list_add(&clk->list, &clocks);
	spin_unlock(&clocks_lock);

	return 0;
}

int s3c24xx_register_clocks(struct clk **clks, int nr_clks)
{
	int fails = 0;

	for (; nr_clks > 0; nr_clks--, clks++) {
		if (s3c24xx_register_clock(*clks) < 0)
			fails++;
	}

	return fails;
}

/* initalise all the clocks */

int __init s3c24xx_register_baseclocks(unsigned long xtal)
{
	printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n");

	clk_xtal.rate = xtal;

	/* register our clocks */

	if (s3c24xx_register_clock(&clk_xtal) < 0)
		printk(KERN_ERR "failed to register master xtal\n");

	if (s3c24xx_register_clock(&clk_mpll) < 0)
		printk(KERN_ERR "failed to register mpll clock\n");

	if (s3c24xx_register_clock(&clk_upll) < 0)
		printk(KERN_ERR "failed to register upll clock\n");

	if (s3c24xx_register_clock(&clk_f) < 0)
		printk(KERN_ERR "failed to register cpu fclk\n");

	if (s3c24xx_register_clock(&clk_h) < 0)
		printk(KERN_ERR "failed to register cpu hclk\n");

	if (s3c24xx_register_clock(&clk_p) < 0)
		printk(KERN_ERR "failed to register cpu pclk\n");

	return 0;
}
Commit	Line	Data
adbefaa5 BD	1	/* linux/arch/arm/plat-s3c24xx/clock.c
	2	*
	3	* Copyright (c) 2004-2005 Simtec Electronics
	4	* Ben Dooks <ben@simtec.co.uk>
	5	*
	6	* S3C24XX Core clock control support
	7	*
	8	* Based on, and code from linux/arch/arm/mach-versatile/clock.c
	9	**
	10	** Copyright (C) 2004 ARM Limited.
	11	** Written by Deep Blue Solutions Limited.
	12	*
	13	*
	14	* This program is free software; you can redistribute it and/or modify
	15	* it under the terms of the GNU General Public License as published by
	16	* the Free Software Foundation; either version 2 of the License, or
	17	* (at your option) any later version.
	18	*
	19	* This program is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License
	25	* along with this program; if not, write to the Free Software
	26	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	27	*/
	28
	29	#include <linux/init.h>
	30	#include <linux/module.h>
	31	#include <linux/kernel.h>
	32	#include <linux/list.h>
	33	#include <linux/errno.h>
	34	#include <linux/err.h>
	35	#include <linux/platform_device.h>
	36	#include <linux/sysdev.h>
	37	#include <linux/interrupt.h>
	38	#include <linux/ioport.h>
	39	#include <linux/clk.h>
	40	#include <linux/spinlock.h>
adbefaa5 BD	41	#include <linux/io.h>
	42
	43	#include <mach/hardware.h>
	44	#include <asm/irq.h>
	45
	46	#include <plat/cpu-freq.h>
	47
	48	#include <plat/clock.h>
	49	#include <plat/cpu.h>
	50
	51	/* clock information */
	52
	53	static LIST_HEAD(clocks);
	54
	55	/* We originally used an mutex here, but some contexts (see resume)
	56	* are calling functions such as clk_set_parent() with IRQs disabled
	57	* causing an BUG to be triggered.
	58	*/
	59	DEFINE_SPINLOCK(clocks_lock);
	60
	61	/* enable and disable calls for use with the clk struct */
	62
	63	static int clk_null_enable(struct clk *clk, int enable)
	64	{
	65	return 0;
	66	}
	67
	68	/* Clock API calls */
	69
	70	struct clk clk_get(struct device dev, const char *id)
	71	{
	72	struct clk *p;
	73	struct clk *clk = ERR_PTR(-ENOENT);
	74	int idno;
	75
	76	if (dev == NULL \|\| dev->bus != &platform_bus_type)
	77	idno = -1;
	78	else
	79	idno = to_platform_device(dev)->id;
	80
	81	spin_lock(&clocks_lock);
	82
	83	list_for_each_entry(p, &clocks, list) {
	84	if (p->id == idno &&
	85	strcmp(id, p->name) == 0 &&
	86	try_module_get(p->owner)) {
	87	clk = p;
	88	break;
	89	}
	90	}
	91
	92	/* check for the case where a device was supplied, but the
	93	* clock that was being searched for is not device specific */
	94
	95	if (IS_ERR(clk)) {
	96	list_for_each_entry(p, &clocks, list) {
	97	if (p->id == -1 && strcmp(id, p->name) == 0 &&
	98	try_module_get(p->owner)) {
	99	clk = p;
	100	break;
	101	}
	102	}
	103	}
	104
105	spin_unlock(&clocks_lock);
106	return clk;
107	}
108
109	void clk_put(struct clk *clk)
110	{
111	module_put(clk->owner);
112	}
113
114	int clk_enable(struct clk *clk)
115	{
116	if (IS_ERR(clk) \|\| clk == NULL)
117	return -EINVAL;
118
119	clk_enable(clk->parent);
120
121	spin_lock(&clocks_lock);
122
123	if ((clk->usage++) == 0)
124	(clk->enable)(clk, 1);
125
126	spin_unlock(&clocks_lock);
127	return 0;
128	}
129
130	void clk_disable(struct clk *clk)
131	{
132	if (IS_ERR(clk) \|\| clk == NULL)
133	return;
134
135	spin_lock(&clocks_lock);
136
137	if ((--clk->usage) == 0)
138	(clk->enable)(clk, 0);
139
140	spin_unlock(&clocks_lock);
141	clk_disable(clk->parent);
142	}
143
144
145	unsigned long clk_get_rate(struct clk *clk)
146	{
147	if (IS_ERR(clk))
148	return 0;
149
150	if (clk->rate != 0)
151	return clk->rate;
152
153	if (clk->get_rate != NULL)
154	return (clk->get_rate)(clk);
155
156	if (clk->parent != NULL)
157	return clk_get_rate(clk->parent);
158
159	return clk->rate;
160	}
161
162	long clk_round_rate(struct clk *clk, unsigned long rate)
163	{
164	if (!IS_ERR(clk) && clk->round_rate)
165	return (clk->round_rate)(clk, rate);
166
167	return rate;
168	}
169
170	int clk_set_rate(struct clk *clk, unsigned long rate)
171	{
172	int ret;
173
174	if (IS_ERR(clk))
175	return -EINVAL;
176
177	/* We do not default just do a clk->rate = rate as
178	* the clock may have been made this way by choice.
179	*/
180
181	WARN_ON(clk->set_rate == NULL);
182
183	if (clk->set_rate == NULL)
184	return -EINVAL;
185
186	spin_lock(&clocks_lock);
187	ret = (clk->set_rate)(clk, rate);
188	spin_unlock(&clocks_lock);
189
190	return ret;
191	}
192
193	struct clk clk_get_parent(struct clk clk)
194	{
195	return clk->parent;
196	}
197
198	int clk_set_parent(struct clk clk, struct clk parent)
199	{
200	int ret = 0;
201
202	if (IS_ERR(clk))
203	return -EINVAL;
204
205	spin_lock(&clocks_lock);
206
207	if (clk->set_parent)
208	ret = (clk->set_parent)(clk, parent);
209
210	spin_unlock(&clocks_lock);
211
212	return ret;
213	}
214
215	EXPORT_SYMBOL(clk_get);
216	EXPORT_SYMBOL(clk_put);
217	EXPORT_SYMBOL(clk_enable);
218	EXPORT_SYMBOL(clk_disable);
219	EXPORT_SYMBOL(clk_get_rate);
220	EXPORT_SYMBOL(clk_round_rate);
221	EXPORT_SYMBOL(clk_set_rate);
222	EXPORT_SYMBOL(clk_get_parent);
223	EXPORT_SYMBOL(clk_set_parent);
224
225	/* base clocks */
226
227	static int clk_default_setrate(struct clk *clk, unsigned long rate)
228	{
229	clk->rate = rate;
230	return 0;
231	}
232
233	struct clk clk_xtal = {
234	.name = "xtal",
235	.id = -1,
236	.rate = 0,
237	.parent = NULL,
238	.ctrlbit = 0,
239	};
240
4b31d8b2 BD	241	struct clk clk_ext = {
	242	.name = "ext",
	243	.id = -1,
	244	};
	245
	246	struct clk clk_epll = {
	247	.name = "epll",
	248	.id = -1,
	249	};
	250
adbefaa5 BD	251	struct clk clk_mpll = {
	252	.name = "mpll",
	253	.id = -1,
	254	.set_rate = clk_default_setrate,
	255	};
	256
	257	struct clk clk_upll = {
	258	.name = "upll",
	259	.id = -1,
	260	.parent = NULL,
	261	.ctrlbit = 0,
	262	};
	263
	264	struct clk clk_f = {
	265	.name = "fclk",
	266	.id = -1,
	267	.rate = 0,
	268	.parent = &clk_mpll,
	269	.ctrlbit = 0,
	270	.set_rate = clk_default_setrate,
	271	};
	272
	273	struct clk clk_h = {
	274	.name = "hclk",
	275	.id = -1,
	276	.rate = 0,
	277	.parent = NULL,
	278	.ctrlbit = 0,
	279	.set_rate = clk_default_setrate,
	280	};
	281
	282	struct clk clk_p = {
	283	.name = "pclk",
	284	.id = -1,
	285	.rate = 0,
	286	.parent = NULL,
	287	.ctrlbit = 0,
	288	.set_rate = clk_default_setrate,
	289	};
	290
	291	struct clk clk_usb_bus = {
	292	.name = "usb-bus",
	293	.id = -1,
	294	.rate = 0,
	295	.parent = &clk_upll,
	296	};
	297
	298
	299
	300	struct clk s3c24xx_uclk = {
	301	.name = "uclk",
	302	.id = -1,
	303	};
	304
	305	/* initialise the clock system */
	306
	307	int s3c24xx_register_clock(struct clk *clk)
	308	{
	309	clk->owner = THIS_MODULE;
	310
	311	if (clk->enable == NULL)
	312	clk->enable = clk_null_enable;
	313
	314	/* add to the list of available clocks */
315
cec444b7 BD	316	/* Quick check to see if this clock has already been registered. */
	317	BUG_ON(clk->list.prev != clk->list.next);
	318
adbefaa5 BD	319	spin_lock(&clocks_lock);
	320	list_add(&clk->list, &clocks);
	321	spin_unlock(&clocks_lock);
	322
	323	return 0;
	324	}
	325
	326	int s3c24xx_register_clocks(struct clk **clks, int nr_clks)
	327	{
	328	int fails = 0;
	329
	330	for (; nr_clks > 0; nr_clks--, clks++) {
	331	if (s3c24xx_register_clock(*clks) < 0)
	332	fails++;
	333	}
	334
	335	return fails;
	336	}
	337
	338	/* initalise all the clocks */
	339
	340	int __init s3c24xx_register_baseclocks(unsigned long xtal)
	341	{
	342	printk(KERN_INFO "S3C24XX Clocks, (c) 2004 Simtec Electronics\n");
	343
	344	clk_xtal.rate = xtal;
	345
	346	/* register our clocks */
	347
	348	if (s3c24xx_register_clock(&clk_xtal) < 0)
	349	printk(KERN_ERR "failed to register master xtal\n");
	350
	351	if (s3c24xx_register_clock(&clk_mpll) < 0)
	352	printk(KERN_ERR "failed to register mpll clock\n");
	353
	354	if (s3c24xx_register_clock(&clk_upll) < 0)
	355	printk(KERN_ERR "failed to register upll clock\n");
	356
	357	if (s3c24xx_register_clock(&clk_f) < 0)
	358	printk(KERN_ERR "failed to register cpu fclk\n");
	359
	360	if (s3c24xx_register_clock(&clk_h) < 0)
	361	printk(KERN_ERR "failed to register cpu hclk\n");
	362
	363	if (s3c24xx_register_clock(&clk_p) < 0)
	364	printk(KERN_ERR "failed to register cpu pclk\n");
	365
	366	return 0;
	367	}
	368