drivers/thermal/db8500_cpufreq_cooling.c

   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/err.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/slab.h>
  26
  27 static int db8500_cpufreq_cooling_probe(struct platform_device *pdev)
  28 {
  29         struct thermal_cooling_device *cdev;
  30
  31         cdev = cpufreq_cooling_register(cpu_present_mask);
  32         if (IS_ERR(cdev)) {
  33                 int ret = PTR_ERR(cdev);
  34
  35                 if (ret != -EPROBE_DEFER)
  36                         dev_err(&pdev->dev,
  37                                 "Failed to register cooling device %d\n",
  38                                 ret);
  39
  40                 return ret;
  41         }
  42
  43         platform_set_drvdata(pdev, cdev);
  44
  45         dev_info(&pdev->dev, "Cooling device registered: %s\n", cdev->type);
  46
  47         return 0;
  48 }
  49
  50 static int db8500_cpufreq_cooling_remove(struct platform_device *pdev)
  51 {
  52         struct thermal_cooling_device *cdev = platform_get_drvdata(pdev);
  53
  54         cpufreq_cooling_unregister(cdev);
  55
  56         return 0;
  57 }
  58
  59 static int db8500_cpufreq_cooling_suspend(struct platform_device *pdev,
  60                 pm_message_t state)
  61 {
  62         return -ENOSYS;
  63 }
  64
  65 static int db8500_cpufreq_cooling_resume(struct platform_device *pdev)
  66 {
  67         return -ENOSYS;
  68 }
  69
  70 #ifdef CONFIG_OF
  71 static const struct of_device_id db8500_cpufreq_cooling_match[] = {
  72         { .compatible = "stericsson,db8500-cpufreq-cooling" },
  73         {},
  74 };
  75 MODULE_DEVICE_TABLE(of, db8500_cpufreq_cooling_match);
  76 #endif
  77
  78 static struct platform_driver db8500_cpufreq_cooling_driver = {
  79         .driver = {
  80                 .name = "db8500-cpufreq-cooling",
  81                 .of_match_table = of_match_ptr(db8500_cpufreq_cooling_match),
  82         },
  83         .probe = db8500_cpufreq_cooling_probe,
  84         .suspend = db8500_cpufreq_cooling_suspend,
  85         .resume = db8500_cpufreq_cooling_resume,
  86         .remove = db8500_cpufreq_cooling_remove,
  87 };
  88
  89 static int __init db8500_cpufreq_cooling_init(void)
  90 {
  91         return platform_driver_register(&db8500_cpufreq_cooling_driver);
  92 }
  93
  94 static void __exit db8500_cpufreq_cooling_exit(void)
  95 {
  96         platform_driver_unregister(&db8500_cpufreq_cooling_driver);
  97 }
  98
  99 /* Should be later than db8500_cpufreq_register */
 100 late_initcall(db8500_cpufreq_cooling_init);
 101 module_exit(db8500_cpufreq_cooling_exit);
 102
 103 MODULE_AUTHOR("Hongbo Zhang <hongbo.zhang@stericsson.com>");
 104 MODULE_DESCRIPTION("DB8500 cpufreq cooling driver");
 105 MODULE_LICENSE("GPL");