arch/arm/mach-tegra/cpuidle-tegra20.c

   1 /*
   2  * CPU idle driver for Tegra CPUs
   3  *
   4  * Copyright (c) 2010-2012, NVIDIA Corporation.
   5  * Copyright (c) 2011 Google, Inc.
   6  * Author: Colin Cross <ccross@android.com>
   7  *         Gary King <gking@nvidia.com>
   8  *
   9  * Rework for 3.3 by Peter De Schrijver <pdeschrijver@nvidia.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but WITHOUT
  17  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  19  * more details.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/cpuidle.h>
  25
  26 #include <asm/cpuidle.h>
  27
  28 static struct cpuidle_driver tegra_idle_driver = {
  29         .name = "tegra_idle",
  30         .owner = THIS_MODULE,
  31         .en_core_tk_irqen = 1,
  32         .state_count = 1,
  33         .states = {
  34                 [0] = ARM_CPUIDLE_WFI_STATE_PWR(600),
  35         },
  36 };
  37
  38 static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device);
  39
  40 int __init tegra20_cpuidle_init(void)
  41 {
  42         int ret;
  43         unsigned int cpu;
  44         struct cpuidle_device *dev;
  45         struct cpuidle_driver *drv = &tegra_idle_driver;
  46
  47         ret = cpuidle_register_driver(&tegra_idle_driver);
  48         if (ret) {
  49                 pr_err("CPUidle driver registration failed\n");
  50                 return ret;
  51         }
  52
  53         for_each_possible_cpu(cpu) {
  54                 dev = &per_cpu(tegra_idle_device, cpu);
  55                 dev->cpu = cpu;
  56
  57                 dev->state_count = drv->state_count;
  58                 ret = cpuidle_register_device(dev);
  59                 if (ret) {
  60                         pr_err("CPU%u: CPUidle device registration failed\n",
  61                                 cpu);
  62                         return ret;
  63                 }
  64         }
  65         return 0;
  66 }