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/of.h>
  21 #include <linux/pm_opp.h>
  22 #include <linux/cpu.h>
  23
  24 #include "omap_device.h"
  25
  26 #include "omap_opp_data.h"
  27
  28 /* Temp variable to allow multiple calls */
  29 static u8 __initdata omap_table_init;
  30
  31 /**
  32  * omap_init_opp_table() - Initialize opp table as per the CPU type
  33  * @opp_def:            opp default list for this silicon
  34  * @opp_def_size:       number of opp entries for this silicon
  35  *
  36  * Register the initial OPP table with the OPP library based on the CPU
  37  * type. This is meant to be used only by SoC specific registration.
  38  */
  39 int __init omap_init_opp_table(struct omap_opp_def *opp_def,
  40                 u32 opp_def_size)
  41 {
  42         int i, r;
  43
  44         if (of_have_populated_dt())
  45                 return -EINVAL;
  46
  47         if (!opp_def || !opp_def_size) {
  48                 pr_err("%s: invalid params!\n", __func__);
  49                 return -EINVAL;
  50         }
  51
  52         /*
  53          * Initialize only if not already initialized even if the previous
  54          * call failed, because, no reason we'd succeed again.
  55          */
  56         if (omap_table_init)
  57                 return -EEXIST;
  58         omap_table_init = 1;
  59
  60         /* Lets now register with OPP library */
  61         for (i = 0; i < opp_def_size; i++, opp_def++) {
  62                 struct omap_hwmod *oh;
  63                 struct device *dev;
  64
  65                 if (!opp_def->hwmod_name) {
  66                         pr_err("%s: NULL name of omap_hwmod, failing [%d].\n",
  67                                 __func__, i);
  68                         return -EINVAL;
  69                 }
  70
  71                 if (!strncmp(opp_def->hwmod_name, "mpu", 3)) {
  72                         /*
  73                          * All current OMAPs share voltage rail and
  74                          * clock source, so CPU0 is used to represent
  75                          * the MPU-SS.
  76                          */
  77                         dev = get_cpu_device(0);
  78                 } else {
  79                         oh = omap_hwmod_lookup(opp_def->hwmod_name);
  80                         if (!oh || !oh->od) {
  81                                 pr_debug("%s: no hwmod or odev for %s, [%d] cannot add OPPs.\n",
  82                                          __func__, opp_def->hwmod_name, i);
  83                                 continue;
  84                         }
  85                         dev = &oh->od->pdev->dev;
  86                 }
  87
  88                 r = dev_pm_opp_add(dev, opp_def->freq, opp_def->u_volt);
  89                 if (r) {
  90                         dev_err(dev, "%s: add OPP %ld failed for %s [%d] result=%d\n",
  91                                 __func__, opp_def->freq,
  92                                 opp_def->hwmod_name, i, r);
  93                 } else {
  94                         if (!opp_def->default_available)
  95                                 r = dev_pm_opp_disable(dev, opp_def->freq);
  96                         if (r)
  97                                 dev_err(dev, "%s: disable %ld failed for %s [%d] result=%d\n",
  98                                         __func__, opp_def->freq,
  99                                         opp_def->hwmod_name, i, r);
 100                 }
 101         }
 102
 103         return 0;
 104 }