path: root/arch/arm/mach-omap2/clockdomain.c

/*
 * OMAP2/3/4 clockdomain framework functions
 *
 * Copyright (C) 2008-2010 Texas Instruments, Inc.
 * Copyright (C) 2008-2010 Nokia Corporation
 *
 * Written by Paul Walmsley and Jouni Högander
 * Added OMAP4 specific support by Abhijit Pagare <abhijitpagare@ti.com>
 *
 * 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.
 */
#undef DEBUG

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/list.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/limits.h>
#include <linux/err.h>

#include <linux/io.h>

#include <linux/bitops.h>

#include "prm.h"
#include "prm-regbits-24xx.h"
#include "cm.h"

#include <plat/clock.h>
#include <plat/powerdomain.h>
#include <plat/clockdomain.h>
#include <plat/prcm.h>

/* clkdm_list contains all registered struct clockdomains */
static LIST_HEAD(clkdm_list);

/* array of clockdomain deps to be added/removed when clkdm in hwsup mode */
static struct clkdm_autodep *autodeps;


/* Private functions */

static struct clockdomain *_clkdm_lookup(const char *name)
{
	struct clockdomain *clkdm, *temp_clkdm;

	if (!name)
		return NULL;

	clkdm = NULL;

	list_for_each_entry(temp_clkdm, &clkdm_list, node) {
		if (!strcmp(name, temp_clkdm->name)) {
			clkdm = temp_clkdm;
			break;
		}
	}

	return clkdm;
}

/**
 * _clkdm_register - register a clockdomain
 * @clkdm: struct clockdomain * to register
 *
 * Adds a clockdomain to the internal clockdomain list.
 * Returns -EINVAL if given a null pointer, -EEXIST if a clockdomain is
 * already registered by the provided name, or 0 upon success.
 */
static int _clkdm_register(struct clockdomain *clkdm)
{
	struct powerdomain *pwrdm;

	if (!clkdm || !clkdm->name)
		return -EINVAL;

	if (!omap_chip_is(clkdm->omap_chip))
		return -EINVAL;

	pwrdm = pwrdm_lookup(clkdm->pwrdm.name);
	if (!pwrdm) {
		pr_err("clockdomain: %s: powerdomain %s does not exist\n",
			clkdm->name, clkdm->pwrdm.name);
		return -EINVAL;
	}
	clkdm->pwrdm.ptr = pwrdm;

	/* Verify that the clockdomain is not already registered */
	if (_clkdm_lookup(clkdm->name))
		return -EEXIST;

	list_add(&clkdm->node, &clkdm_list);

	pwrdm_add_clkdm(pwrdm, clkdm);

	pr_debug("clockdomain: registered %s\n", clkdm->name);

	return 0;
}

/* _clkdm_deps_lookup - look up the specified clockdomain in a clkdm list */
static struct clkdm_dep *_clkdm_deps_lookup(struct clockdomain *clkdm,
					    struct clkdm_dep *deps)
{
	struct clkdm_dep *cd;

	if (!clkdm || !deps || !omap_chip_is(clkdm->omap_chip))
		return ERR_PTR(-EINVAL);

	for (cd = deps; cd->clkdm_name; cd++) {
		if (!omap_chip_is(cd->omap_chip))
			continue;

		if (!cd->clkdm && cd->clkdm_name)
			cd->clkdm = _clkdm_lookup(cd->clkdm_name);

		if (cd->clkdm == clkdm)
			break;
	}

	if (!cd->clkdm_name)
		return ERR_PTR(-ENOENT);

	return cd;
}

/*
 * _autodep_lookup - resolve autodep clkdm names to clkdm pointers; store
 * @autodep: struct clkdm_autodep * to resolve
 *
 * Resolve autodep clockdomain names to clockdomain pointers via
 * clkdm_lookup() and store the pointers in the autodep structure.  An
 * "autodep" is a clockdomain sleep/wakeup dependency that is
 * automatically added and removed whenever clocks in the associated
 * clockdomain are enabled or disabled (respectively) when the
 * clockdomain is in hardware-supervised mode.	Meant to be called
 * once at clockdomain layer initialization, since these should remain
 * fixed for a particular architecture.  No return value.
 */
static void _autodep_lookup(struct clkdm_autodep *autodep)
{
	struct clockdomain *clkdm;

	if (!autodep)
		return;

	if (!omap_chip_is(autodep->omap_chip))
		return;

	clkdm = clkdm_lookup(autodep->clkdm.name);
	if (!clkdm) {
		pr_err("clockdomain: autodeps: clockdomain %s does not exist\n",
			 autodep->clkdm.name);
		clkdm = ERR_PTR(-ENOENT);
	}
	autodep->clkdm.ptr = clkdm;
}

/*
 * _clkdm_add_autodeps - add auto sleepdeps/wkdeps to clkdm upon clock enable
 * @clkdm: struct clockdomain *
 *
 * Add the "autodep" sleep & wakeup dependencies to clockdomain 'clkdm'
 * in hardware-supervised mode.  Meant to be called from clock framework
 * when a clock inside clockdomain 'clkdm' is enabled.	No return value.
 */
static void _clkdm_add_autodeps(struct clockdomain *clkdm</