+++ /dev/null
-/*
- * Based on arch/arm/plat-omap/clock.c
- *
- * Copyright (C) 2004 - 2005 Nokia corporation
- * Written by Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com>
- * Modified for omap shared clock framework by Tony Lindgren <tony@atomide.com>
- * Copyright 2007 Freescale Semiconductor, Inc. All Rights Reserved.
- * Copyright 2008 Juergen Beisert, kernel@pengutronix.de
- *
- * 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., 51 Franklin Street, Fifth Floor, Boston,
- * MA 02110-1301, USA.
- */
-
-/* #define DEBUG */
-
-#include <linux/clk.h>
-#include <linux/err.h>
-#include <linux/errno.h>
-#include <linux/init.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/list.h>
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/platform_device.h>
-#include <linux/proc_fs.h>
-#include <linux/semaphore.h>
-#include <linux/string.h>
-
-#include <mach/clock.h>
-#include <mach/hardware.h>
-
-#ifndef CONFIG_COMMON_CLK
-static LIST_HEAD(clocks);
-static DEFINE_MUTEX(clocks_mutex);
-
-/*-------------------------------------------------------------------------
- * Standard clock functions defined in include/linux/clk.h
- *-------------------------------------------------------------------------*/
-
-static void __clk_disable(struct clk *clk)
-{
- if (clk == NULL || IS_ERR(clk))
- return;
- WARN_ON(!clk->usecount);
-
- if (!(--clk->usecount)) {
- if (clk->disable)
- clk->disable(clk);
- __clk_disable(clk->parent);
- __clk_disable(clk->secondary);
- }
-}
-
-static int __clk_enable(struct clk *clk)
-{
- if (clk == NULL || IS_ERR(clk))
- return -EINVAL;
-
- if (clk->usecount++ == 0) {
- __clk_enable(clk->parent);
- __clk_enable(clk->secondary);
-
- if (clk->enable)
- clk->enable(clk);
- }
- return 0;
-}
-
-/* This function increments the reference count on the clock and enables the
- * clock if not already enabled. The parent clock tree is recursively enabled
- */
-int clk_enable(struct clk *clk)
-{
- int ret = 0;
-
- if (clk == NULL || IS_ERR(clk))
- return -EINVAL;
-
- mutex_lock(&clocks_mutex);
- ret = __clk_enable(clk);
- mutex_unlock(&clocks_mutex);
-
- return ret;
-}
-EXPORT_SYMBOL(clk_enable);
-
-/* This function decrements the reference count on the clock and disables
- * the clock when reference count is 0. The parent clock tree is
- * recursively disabled
- */
-void clk_disable(struct clk *clk)
-{
- if (clk == NULL || IS_ERR(clk))
- return;
-
- mutex_lock(&clocks_mutex);
- __clk_disable(clk);
- mutex_unlock(&clocks_mutex);
-}
-EXPORT_SYMBOL(clk_disable);
-
-/* Retrieve the *current* clock rate. If the clock itself
- * does not provide a special calculation routine, ask
- * its parent and so on, until one is able to return
- * a valid clock rate
- */
-unsigned long clk_get_rate(struct clk *clk)
-{
- if (clk == NULL || IS_ERR(clk))
- return 0UL;
-
- if (clk->get_rate)
- return clk->get_rate(clk);
-
- return clk_get_rate(clk->parent);
-}
-EXPORT_SYMBOL(clk_get_rate);
-
-/* Round the requested clock rate to the nearest supported
- * rate that is less than or equal to the requested rate.
- * This is dependent on the clock's current parent.
- */
-long clk_round_rate(struct clk *clk, unsigned long rate)
-{
- if (clk == NULL || IS_ERR(clk) || !clk->round_rate)
- return 0;
-
- return clk->round_rate(clk, rate);
-}
-EXPORT_SYMBOL(clk_round_rate);
-
-/* Set the clock to the requested clock rate. The rate must
- * match a supported rate exactly based on what clk_round_rate returns
- */
-int clk_set_rate(struct clk *clk, unsigned long rate)
-{
- int ret = -EINVAL;
-
- if (clk == NULL || IS_ERR(clk) || clk->set_rate == NULL || rate == 0)
- return ret;
-
- mutex_lock(&clocks_mutex);
- ret = clk->set_rate(clk, rate);
- mutex_unlock(&clocks_mutex);
-
- return ret;
-}
-EXPORT_SYMBOL(clk_set_rate);
-
-/* Set the clock's parent to another clock source */
-int clk_set_parent(struct clk *clk, struct clk *parent)
-{
- int ret = -EINVAL;
- struct clk *old;
-
- if (clk == NULL || IS_ERR(clk) || parent == NULL ||
- IS_ERR(parent) || clk->set_parent == NULL)
- return ret;
-
- if (clk->usecount)
- clk_enable(parent);
-
- mutex_lock(&clocks_mutex);
- ret = clk->set_parent(clk, parent);
- if (ret == 0) {
- old = clk->parent;
- clk->parent = parent;
- } else {
- old = parent;
- }
- mutex_unlock(&clocks_mutex);
-
- if (clk->usecount)
- clk_disable(old);
-
- return ret;
-}
-EXPORT_SYMBOL(clk_set_parent);
-
-/* Retrieve the clock's parent clock source */
-struct clk *clk_get_parent(struct clk *clk)
-{
- struct clk *ret = NULL;
-
- if (clk == NULL || IS_ERR(clk))
- return ret;
-
- return clk->parent;
-}
-EXPORT_SYMBOL(clk_get_parent);
-
-#else
-
-/*
- * Lock to protect the clock module (ccm) registers. Used
- * on all i.MXs
- */
-DEFINE_SPINLOCK(imx_ccm_lock);
-
-#endif /* CONFIG_COMMON_CLK */
-
-/*
- * Get the resulting clock rate from a PLL register value and the input
- * frequency. PLLs with this register layout can at least be found on
- * MX1, MX21, MX27 and MX31
- *
- * mfi + mfn / (mfd + 1)
- * f = 2 * f_ref * --------------------
- * pd + 1
- */
-unsigned long mxc_decode_pll(unsigned int reg_val, u32 freq)
-{
- long long ll;
- int mfn_abs;
- unsigned int mfi, mfn, mfd, pd;
-
- mfi = (reg_val >> 10) & 0xf;
- mfn = reg_val & 0x3ff;
- mfd = (reg_val >> 16) & 0x3ff;
- pd = (reg_val >> 26) & 0xf;
-
- mfi = mfi <= 5 ? 5 : mfi;
-
- mfn_abs = mfn;
-
- /* On all i.MXs except i.MX1 and i.MX21 mfn is a 10bit
- * 2's complements number
- */
- if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
- mfn_abs = 0x400 - mfn;
-
- freq *= 2;
- freq /= pd + 1;
-
- ll = (unsigned long long)freq * mfn_abs;
-
- do_div(ll, mfd + 1);
-
- if (!cpu_is_mx1() && !cpu_is_mx21() && mfn >= 0x200)
- ll = -ll;
-
- ll = (freq * mfi) + ll;
-
- return ll;
-}
projects / cascardo / linux.git / blobdiff