Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0318e693 authored by Russell King's avatar Russell King Committed by Russell King
Browse files

[ARM] clkdev: add generic clkdev infrastructure 



Add some generic infrastructure to assist looking up struct clks
for the ARM architecture.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent ed313489

arch/arm/common/Kconfig

+3 −0
Original line number Original line Diff line number Diff line
@@ -33,3 +33,6 @@ config SHARPSL_PM 




config SHARP_SCOOP

config SHARP_SCOOP

	bool

	bool



config COMMON_CLKDEV

	bool

arch/arm/common/Makefile

+1 −0
Original line number Original line Diff line number Diff line
@@ -17,3 +17,4 @@ obj-$(CONFIG_SHARP_SCOOP) += scoop.o 
obj-$(CONFIG_ARCH_IXP2000)	+= uengine.o

obj-$(CONFIG_ARCH_IXP2000)	+= uengine.o

obj-$(CONFIG_ARCH_IXP23XX)	+= uengine.o

obj-$(CONFIG_ARCH_IXP23XX)	+= uengine.o

obj-$(CONFIG_PCI_HOST_ITE8152)  += it8152.o

obj-$(CONFIG_PCI_HOST_ITE8152)  += it8152.o

obj-$(CONFIG_COMMON_CLKDEV)	+= clkdev.o

arch/arm/common/clkdev.c

0 → 100644
+128 −0
Original line number Original line Diff line number Diff line 
/*

 *  arch/arm/common/clkdev.c

 *

 *  Copyright (C) 2008 Russell King.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * Helper for the clk API to assist looking up a struct clk.

 */

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/device.h>

#include <linux/list.h>

#include <linux/errno.h>

#include <linux/err.h>

#include <linux/string.h>

#include <linux/mutex.h>



#include <asm/clkdev.h>

#include <mach/clkdev.h>



static LIST_HEAD(clocks);

static DEFINE_MUTEX(clocks_mutex);



static struct clk *clk_find(const char *dev_id, const char *con_id)

{

	struct clk_lookup *p;

	struct clk *clk = NULL;

	int match, best = 0;



	list_for_each_entry(p, &clocks, node) {

		if ((p->dev_id && !dev_id) || (p->con_id && !con_id))

			continue;

		match = 0;

		if (p->dev_id)

			match += 2 * (strcmp(p->dev_id, dev_id) == 0);

		if (p->con_id)

			match += 1 * (strcmp(p->con_id, con_id) == 0);

		if (match == 0)

			continue;



		if (match > best) {

			clk = p->clk;

			best = match;

		}

	}

	return clk;

}



struct clk *clk_get(struct device *dev, const char *con_id)

{

	const char *dev_id = dev ? dev_name(dev) : NULL;

	struct clk *clk;



	mutex_lock(&clocks_mutex);

	clk = clk_find(dev_id, con_id);

	if (clk && !__clk_get(clk))

		clk = NULL;

	mutex_unlock(&clocks_mutex);



	return clk ? clk : ERR_PTR(-ENOENT);

}

EXPORT_SYMBOL(clk_get);



void clk_put(struct clk *clk)

{

	__clk_put(clk);

}

EXPORT_SYMBOL(clk_put);



void clkdev_add(struct clk_lookup *cl)

{

	mutex_lock(&clocks_mutex);

	list_add_tail(&cl->node, &clocks);

	mutex_unlock(&clocks_mutex);

}

EXPORT_SYMBOL(clkdev_add);



#define MAX_DEV_ID	20

#define MAX_CON_ID	16



struct clk_lookup_alloc {

	struct clk_lookup cl;

	char	dev_id[MAX_DEV_ID];

	char	con_id[MAX_CON_ID];

};



struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,

	const char *dev_fmt, ...)

{

	struct clk_lookup_alloc *cla;



	cla = kzalloc(sizeof(*cla), GFP_KERNEL);

	if (!cla)

		return NULL;



	cla->cl.clk = clk;

	if (con_id) {

		strlcpy(cla->con_id, con_id, sizeof(cla->con_id));

		cla->cl.con_id = cla->con_id;

	}



	if (dev_fmt) {

		va_list ap;



		va_start(ap, dev_fmt);

		vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);

		cla->cl.dev_id = cla->dev_id;

		va_end(ap);

	}



	return &cla->cl;

}

EXPORT_SYMBOL(clkdev_alloc);



/*

 * clkdev_drop - remove a clock dynamically allocated

 */

void clkdev_drop(struct clk_lookup *cl)

{

	mutex_lock(&clocks_mutex);

	list_del(&cl->node);

	mutex_unlock(&clocks_mutex);

	kfree(cl);

}

EXPORT_SYMBOL(clkdev_drop);

arch/arm/include/asm/clkdev.h

0 → 100644
+30 −0
Original line number Original line Diff line number Diff line 
/*

 *  arch/arm/include/asm/clkdev.h

 *

 *  Copyright (C) 2008 Russell King.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 *

 * Helper for the clk API to assist looking up a struct clk.

 */

#ifndef __ASM_CLKDEV_H

#define __ASM_CLKDEV_H



struct clk;



struct clk_lookup {

	struct list_head	node;

	const char		*dev_id;

	const char		*con_id;

	struct clk		*clk;

};



struct clk_lookup *clkdev_alloc(struct clk *clk, const char *con_id,

	const char *dev_fmt, ...);



void clkdev_add(struct clk_lookup *cl);

void clkdev_drop(struct clk_lookup *cl);



#endif