arch/arm/mach-omap2/opp.c

   1 /*
   2  * OMAP SoC specific OPP wrapper function
   3  *
   4  * Copyright (C) 2009-2010 Texas Instruments Incorporated - http://www.ti.com/
   5  *      Nishanth Menon
   6  *      Kevin Hilman
   7  * Copyright (C) 2010 Nokia Corporation.
   8  *      Eduardo Valentin
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License version 2 as
  12  * published by the Free Software Foundation.
  13  *
  14  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  15  * kind, whether express or implied; without even the implied warranty
  16  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19 #include <linux/module.h>
  20 #include <linux/opp.h>
  21
  22 #include <plat/omap_device.h>
  23
  24 #include "omap_opp_data.h"
  25
  26 /* Temp variable to allow multiple calls */
  27 static u8 __initdata omap_table_init;
  28
  29 /**
  30  * omap_init_opp_table() - Initialize opp table as per the CPU type
  31  * @opp_def:            opp default list for this silicon
  32  * @opp_def_size:       number of opp entries for this silicon
  33  *
  34  * Register the initial OPP table with the OPP library based on the CPU
  35  * type. This is meant to be used only by SoC specific registration.
  36  */
  37 int __init omap_init_opp_table(struct omap_opp_def *opp_def,
  38                 u32 opp_def_size)
  39 {
  40         int i, r;
  41
  42         if (!opp_def || !opp_def_size) {
  43                 pr_err("%s: invalid params!\n", __func__);
  44                 return -EINVAL;
  45         }
  46
  47         /*
  48          * Initialize only if not already initialized even if the previous
  49          * call failed, because, no reason we'd succeed again.
  50          */
  51         if (omap_table_init)
  52                 return -EEXIST;
  53         omap_table_init = 1;
  54
  55         /* Lets now register with OPP library */
  56         for (i = 0; i < opp_def_size; i++) {
  57                 struct omap_hwmod *oh;
  58                 struct device *dev;
  59
  60                 if (!opp_def->hwmod_name) {
  61                         pr_err("%s: NULL name of omap_hwmod, failing [%d].\n",
  62                                 __func__, i);
  63                         return -EINVAL;
  64                 }
  65                 oh = omap_hwmod_lookup(opp_def->hwmod_name);
  66                 if (!oh || !oh->od) {
  67                         pr_warn("%s: no hwmod or odev for %s, [%d] "
  68                                 "cannot add OPPs.\n", __func__,
  69                                 opp_def->hwmod_name, i);
  70                         return -EINVAL;
  71                 }
  72                 dev = &oh->od->pdev.dev;
  73
  74                 r = opp_add(dev, opp_def->freq, opp_def->u_volt);
  75                 if (r) {
  76                         dev_err(dev, "%s: add OPP %ld failed for %s [%d] "
  77                                 "result=%d\n",
  78                                __func__, opp_def->freq,
  79                                opp_def->hwmod_name, i, r);
  80                 } else {
  81                         if (!opp_def->default_available)
  82                                 r = opp_disable(dev, opp_def->freq);
  83                         if (r)
  84                                 dev_err(dev, "%s: disable %ld failed for %s "
  85                                         "[%d] result=%d\n",
  86                                         __func__, opp_def->freq,
  87                                         opp_def->hwmod_name, i, r);
  88                 }
  89                 opp_def++;
  90         }
  91
  92         return 0;
  93 }