arch/arm/mach-omap2/pm_bus.c

   1 /*
   2  * Runtime PM support code for OMAP
   3  *
   4  * Author: Kevin Hilman, Deep Root Systems, LLC
   5  *
   6  * Copyright (C) 2010 Texas Instruments, Inc.
   7  *
   8  * This file is licensed under the terms of the GNU General Public
   9  * License version 2. This program is licensed "as is" without any
  10  * warranty of any kind, whether express or implied.
  11  */
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/io.h>
  15 #include <linux/pm_runtime.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/mutex.h>
  18
  19 #include <plat/omap_device.h>
  20 #include <plat/omap-pm.h>
  21
  22 #ifdef CONFIG_PM_RUNTIME
  23 static int omap_pm_runtime_suspend(struct device *dev)
  24 {
  25         struct platform_device *pdev = to_platform_device(dev);
  26         int r, ret = 0;
  27
  28         dev_dbg(dev, "%s\n", __func__);
  29
  30         ret = pm_generic_runtime_suspend(dev);
  31
  32         if (!ret && dev->parent == &omap_device_parent) {
  33                 r = omap_device_idle(pdev);
  34                 WARN_ON(r);
  35         }
  36
  37         return ret;
  38 };
  39
  40 static int omap_pm_runtime_resume(struct device *dev)
  41 {
  42         struct platform_device *pdev = to_platform_device(dev);
  43         int r;
  44
  45         dev_dbg(dev, "%s\n", __func__);
  46
  47         if (dev->parent == &omap_device_parent) {
  48                 r = omap_device_enable(pdev);
  49                 WARN_ON(r);
  50         }
  51
  52         return pm_generic_runtime_resume(dev);
  53 };
  54 #else
  55 #define omap_pm_runtime_suspend NULL
  56 #define omap_pm_runtime_resume NULL
  57 #endif /* CONFIG_PM_RUNTIME */
  58
  59 static int __init omap_pm_runtime_init(void)
  60 {
  61         const struct dev_pm_ops *pm;
  62         struct dev_pm_ops *omap_pm;
  63
  64         pm = platform_bus_get_pm_ops();
  65         if (!pm) {
  66                 pr_err("%s: unable to get dev_pm_ops from platform_bus\n",
  67                         __func__);
  68                 return -ENODEV;
  69         }
  70
  71         omap_pm = kmemdup(pm, sizeof(struct dev_pm_ops), GFP_KERNEL);
  72         if (!omap_pm) {
  73                 pr_err("%s: unable to alloc memory for new dev_pm_ops\n",
  74                         __func__);
  75                 return -ENOMEM;
  76         }
  77
  78         omap_pm->runtime_suspend = omap_pm_runtime_suspend;
  79         omap_pm->runtime_resume = omap_pm_runtime_resume;
  80
  81         platform_bus_set_pm_ops(omap_pm);
  82
  83         return 0;
  84 }
  85 core_initcall(omap_pm_runtime_init);