LXR linux/drivers/thermal/db8500_cpufreq

   1/*
   2 * db8500_cpufreq_cooling.c - DB8500 cpufreq works as cooling device.
   3 *
   4 * Copyright (C) 2012 ST-Ericsson
   5 * Copyright (C) 2012 Linaro Ltd.
   6 *
   7 * Author: Hongbo Zhang <hongbo.zhang@linaro.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License as published by
  11 * the Free Software Foundation; either version 2 of the License, or
  12 * (at your option) any later version.
  13 *
  14 * This program is distributed in the hope that it will be useful,
  15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 * GNU General Public License for more details.
  18 */
  19
  20#include <linux/cpu_cooling.h>
  21#include <linux/cpufreq.h>
  22#include <linux/err.h>
  23#include <linux/module.h>
  24#include <linux/of.h>
  25#include <linux/platform_device.h>
  26#include <linux/slab.h>
  27
  28static int db8500_cpufreq_cooling_probe(struct platform_device *pdev)
  29{
  30        struct thermal_cooling_device *cdev;
  31        struct cpumask mask_val;
  32
  33        /* make sure cpufreq driver has been initialized */
  34        if (!cpufreq_frequency_get_table(0))
  35                return -EPROBE_DEFER;
  36
  37        cpumask_set_cpu(0, &mask_val);
  38        cdev = cpufreq_cooling_register(&mask_val);
  39
  40        if (IS_ERR(cdev)) {
  41                dev_err(&pdev->dev, "Failed to register cooling device\n");
  42                return PTR_ERR(cdev);
  43        }
  44
  45        platform_set_drvdata(pdev, cdev);
  46
  47        dev_info(&pdev->dev, "Cooling device registered: %s\n", cdev->type);
  48
  49        return 0;
  50}
  51
  52static int db8500_cpufreq_cooling_remove(struct platform_device *pdev)
  53{
  54        struct thermal_cooling_device *cdev = platform_get_drvdata(pdev);
  55
  56        cpufreq_cooling_unregister(cdev);
  57
  58        return 0;
  59}
  60
  61static int db8500_cpufreq_cooling_suspend(struct platform_device *pdev,
  62                pm_message_t state)
  63{
  64        return -ENOSYS;
  65}
  66
  67static int db8500_cpufreq_cooling_resume(struct platform_device *pdev)
  68{
  69        return -ENOSYS;
  70}
  71
  72#ifdef CONFIG_OF
  73static const struct of_device_id db8500_cpufreq_cooling_match[] = {
  74        { .compatible = "stericsson,db8500-cpufreq-cooling" },
  75        {},
  76};
  77#endif
  78
  79static struct platform_driver db8500_cpufreq_cooling_driver = {
  80        .driver = {
  81                .owner = THIS_MODULE,
  82                .name = "db8500-cpufreq-cooling",
  83                .of_match_table = of_match_ptr(db8500_cpufreq_cooling_match),
  84        },
  85        .probe = db8500_cpufreq_cooling_probe,
  86        .suspend = db8500_cpufreq_cooling_suspend,
  87        .resume = db8500_cpufreq_cooling_resume,
  88        .remove = db8500_cpufreq_cooling_remove,
  89};
  90
  91static int __init db8500_cpufreq_cooling_init(void)
  92{
  93        return platform_driver_register(&db8500_cpufreq_cooling_driver);
  94}
  95
  96static void __exit db8500_cpufreq_cooling_exit(void)
  97{
  98        platform_driver_unregister(&db8500_cpufreq_cooling_driver);
  99}
 100
 101/* Should be later than db8500_cpufreq_register */
 102late_initcall(db8500_cpufreq_cooling_init);
 103module_exit(db8500_cpufreq_cooling_exit);
 104
 105MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
 106MODULE_DESCRIPTION("DB8500 cpufreq cooling driver");
 107MODULE_LICENSE("GPL");
 108