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 #include <linux/cpu.h>
  22
  23 #include "omap_device.h"
  24
  25 #include "omap_opp_data.h"
  26
  27 /* Temp variable to allow multiple calls */
  28 static u8 __initdata omap_table_init;
  29
  30 /**
  31  * omap_init_opp_table() - Initialize opp table as per the CPU type
  32  * @opp_def:            opp default list for this silicon
  33  * @opp_def_size:       number of opp entries for this silicon
  34  *
  35  * Register the initial OPP table with the OPP library based on the CPU
  36  * type. This is meant to be used only by SoC specific registration.
  37  */
  38 int __init omap_init_opp_table(struct omap_opp_def *opp_def,
  39                 u32 opp_def_size)
  40 {
  41         int i, r;
  42
  43         if (!opp_def || !opp_def_size) {
  44                 pr_err("%s: invalid params!\n", __func__);
  45                 return -EINVAL;
  46         }
  47
  48         /*
  49          * Initialize only if not already initialized even if the previous
  50          * call failed, because, no reason we'd succeed again.
  51          */
  52         if (omap_table_init)
  53                 return -EEXIST;
  54         omap_table_init = 1;
  55
  56         /* Lets now register with OPP library */
  57         for (i = 0; i < opp_def_size; i++, opp_def++) {
  58                 struct omap_hwmod *oh;
  59                 struct device *dev;
  60
  61                 if (!opp_def->hwmod_name) {
  62                         pr_err("%s: NULL name of omap_hwmod, failing [%d].\n",
  63                                 __func__, i);
  64                         return -EINVAL;
  65                 }
  66
  67                 if (!strncmp(opp_def->hwmod_name, "mpu", 3)) {
  68                         /*
  69                          * All current OMAPs share voltage rail and
  70                          * clock source, so CPU0 is used to represent
  71                          * the MPU-SS.
  72                          */
  73                         dev = get_cpu_device(0);
  74                 } else {
  75                         oh = omap_hwmod_lookup(opp_def->hwmod_name);
  76                         if (!oh || !oh->od) {
  77                                 pr_debug("%s: no hwmod or odev for %s, [%d] cannot add OPPs.\n",
  78                                          __func__, opp_def->hwmod_name, i);
  79                                 continue;
  80                         }
  81                         dev = &oh->od->pdev->dev;
  82                 }
  83
  84                 r = opp_add(dev, opp_def->freq, opp_def->u_volt);
  85                 if (r) {
  86                         dev_err(dev, "%s: add OPP %ld failed for %s [%d] result=%d\n",
  87                                 __func__, opp_def->freq,
  88                                 opp_def->hwmod_name, i, r);
  89                 } else {
  90                         if (!opp_def->default_available)
  91                                 r = opp_disable(dev, opp_def->freq);
  92                         if (r)
  93                                 dev_err(dev, "%s: disable %ld failed for %s [%d] result=%d\n",
  94                                         __func__, opp_def->freq,
  95                                         opp_def->hwmod_name, i, r);
  96                 }
  97         }
  98
  99         return 0;
 100 }