clock36xx.c

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/*
 * OMAP36xx-specific clkops
 *
 * Copyright (C) 2010 Texas Instruments, Inc.
 * Copyright (C) 2010 Nokia Corporation
 *
 * Mike Turquette
 * Vijaykumar GN
 * Paul Walmsley
 *
 * Parts of this code are based on code written by
 * Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu,
 * 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.
 */
#undef DEBUG

#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>

#include <plat/clock.h>

#include "clock.h"
#include "clock36xx.h"


static int omap36xx_pwrdn_clk_enable_with_hsdiv_restore(struct clk *clk)
{
    u32 dummy_v, orig_v, clksel_shift;
    int ret;

    /* Clear PWRDN bit of HSDIVIDER */
    ret = omap2_dflt_clk_enable(clk);

    /* Restore the dividers */
    if (!ret) {
        clksel_shift = __ffs(clk->parent->clksel_mask);
        orig_v = __raw_readl(clk->parent->clksel_reg);
        dummy_v = orig_v;

        /* Write any other value different from the Read value */
        dummy_v ^= (1 << clksel_shift);
        __raw_writel(dummy_v, clk->parent->clksel_reg);

        /* Write the original divider */
        __raw_writel(orig_v, clk->parent->clksel_reg);
    }

    return ret;
}

const struct clkops clkops_omap36xx_pwrdn_with_hsdiv_wait_restore = {
    .enable     = omap36xx_pwrdn_clk_enable_with_hsdiv_restore,
    .disable    = omap2_dflt_clk_disable,
    .find_companion = omap2_clk_dflt_find_companion,
    .find_idlest    = omap2_clk_dflt_find_idlest,
};