opp.c

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/*
 * OMAP SoC specific OPP wrapper function
 *
 * Copyright (C) 2009-2010 Texas Instruments Incorporated - http://www.ti.com/
 *  Nishanth Menon
 *  Kevin Hilman
 * Copyright (C) 2010 Nokia Corporation.
 *      Eduardo Valentin
 *
 * 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.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */
#include <linux/module.h>
#include <linux/opp.h>
#include <linux/cpu.h>

#include <plat/omap_device.h>

#include "omap_opp_data.h"

/* Temp variable to allow multiple calls */
static u8 __initdata omap_table_init;

int __init omap_init_opp_table(struct omap_opp_def *opp_def,
        u32 opp_def_size)
{
    int i, r;

    if (!opp_def || !opp_def_size) {
        pr_err("%s: invalid params!\n", __func__);
        return -EINVAL;
    }

    /*
     * Initialize only if not already initialized even if the previous
     * call failed, because, no reason we'd succeed again.
     */
    if (omap_table_init)
        return -EEXIST;
    omap_table_init = 1;

    /* Lets now register with OPP library */
    for (i = 0; i < opp_def_size; i++, opp_def++) {
        struct omap_hwmod *oh;
        struct device *dev;

        if (!opp_def->hwmod_name) {
            pr_err("%s: NULL name of omap_hwmod, failing [%d].\n",
                __func__, i);
            return -EINVAL;
        }

        if (!strncmp(opp_def->hwmod_name, "mpu", 3)) {
            /* 
             * All current OMAPs share voltage rail and
             * clock source, so CPU0 is used to represent
             * the MPU-SS.
             */
            dev = get_cpu_device(0);
        } else {
            oh = omap_hwmod_lookup(opp_def->hwmod_name);
            if (!oh || !oh->od) {
                pr_debug("%s: no hwmod or odev for %s, [%d] cannot add OPPs.\n",
                     __func__, opp_def->hwmod_name, i);
                continue;
            }
            dev = &oh->od->pdev->dev;
        }

        r = opp_add(dev, opp_def->freq, opp_def->u_volt);
        if (r) {
            dev_err(dev, "%s: add OPP %ld failed for %s [%d] result=%d\n",
                __func__, opp_def->freq,
                opp_def->hwmod_name, i, r);
        } else {
            if (!opp_def->default_available)
                r = opp_disable(dev, opp_def->freq);
            if (r)
                dev_err(dev, "%s: disable %ld failed for %s [%d] result=%d\n",
                    __func__, opp_def->freq,
                    opp_def->hwmod_name, i, r);
        }
    }

    return 0;
}