arch/arm/mach-omap2/pm.c

   1 /*
   2  * linux/arch/arm/mach-omap2/pm.c
   3  *
   4  * OMAP Power Management Common Routines
   5  *
   6  * Copyright (C) 2005 Texas Instruments, Inc.
   7  * Copyright (C) 2006-2008 Nokia Corporation
   8  *
   9  * Written by:
  10  * Richard Woodruff <r-woodruff2@ti.com>
  11  * Tony Lindgren
  12  * Juha Yrjola
  13  * Amit Kucheria <amit.kucheria@nokia.com>
  14  * Igor Stoppa <igor.stoppa@nokia.com>
  15  * Jouni Hogander
  16  *
  17  * Based on pm.c for omap1
  18  *
  19  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License version 2 as
  21  * published by the Free Software Foundation.
  22  */
  23
  24 #include <linux/suspend.h>
  25 #include <linux/time.h>
  26
  27 #include <mach/cpu.h>
  28 #include <asm/mach/time.h>
  29 #include <asm/atomic.h>
  30
  31 #include <mach/pm.h>
  32 #include "pm.h"
  33
  34 unsigned short enable_dyn_sleep;
  35 unsigned short clocks_off_while_idle;
  36 atomic_t sleep_block = ATOMIC_INIT(0);
  37
  38 static ssize_t idle_show(struct kobject *, struct kobj_attribute *, char *);
  39 static ssize_t idle_store(struct kobject *k, struct kobj_attribute *,
  40                           const char *buf, size_t n);
  41
  42 static struct kobj_attribute sleep_while_idle_attr =
  43         __ATTR(sleep_while_idle, 0644, idle_show, idle_store);
  44
  45 static struct kobj_attribute clocks_off_while_idle_attr =
  46         __ATTR(clocks_off_while_idle, 0644, idle_show, idle_store);
  47
  48 static ssize_t idle_show(struct kobject *kobj, struct kobj_attribute *attr,
  49                          char *buf)
  50 {
  51         if (attr == &sleep_while_idle_attr)
  52                 return sprintf(buf, "%hu\n", enable_dyn_sleep);
  53         else if (attr == &clocks_off_while_idle_attr)
  54                 return sprintf(buf, "%hu\n", clocks_off_while_idle);
  55         else
  56                 return -EINVAL;
  57 }
  58
  59 static ssize_t idle_store(struct kobject *kobj, struct kobj_attribute *attr,
  60                           const char *buf, size_t n)
  61 {
  62         unsigned short value;
  63
  64         if (sscanf(buf, "%hu", &value) != 1 ||
  65             (value != 0 && value != 1)) {
  66                 printk(KERN_ERR "idle_store: Invalid value\n");
  67                 return -EINVAL;
  68         }
  69
  70         if (attr == &sleep_while_idle_attr)
  71                 enable_dyn_sleep = value;
  72         else if (attr == &clocks_off_while_idle_attr)
  73                 clocks_off_while_idle = value;
  74         else
  75                 return -EINVAL;
  76
  77         return n;
  78 }
  79
  80 void omap2_block_sleep(void)
  81 {
  82         atomic_inc(&sleep_block);
  83 }
  84
  85 void omap2_allow_sleep(void)
  86 {
  87         int i;
  88
  89         i = atomic_dec_return(&sleep_block);
  90         BUG_ON(i < 0);
  91 }
  92
  93 static int __init omap_pm_init(void)
  94 {
  95         int error = -1;
  96
  97         if (cpu_is_omap24xx())
  98                 error = omap2_pm_init();
  99         if (cpu_is_omap34xx())
 100                 error = omap3_pm_init();
 101         if (error) {
 102                 printk(KERN_ERR "omap2|3_pm_init failed: %d\n", error);
 103                 return error;
 104         }
 105
 106         /* disabled till drivers are fixed */
 107         enable_dyn_sleep = 0;
 108         error = sysfs_create_file(power_kobj, &sleep_while_idle_attr.attr);
 109         if (error)
 110                 printk(KERN_ERR "sysfs_create_file failed: %d\n", error);
 111         error = sysfs_create_file(power_kobj,
 112                                   &clocks_off_while_idle_attr.attr);
 113         if (error)
 114                 printk(KERN_ERR "sysfs_create_file failed: %d\n", error);
 115
 116         return error;
 117 }
 118
 119 late_initcall(omap_pm_init);