drivers/acpi/proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/proc_fs.h>
   3 #include <linux/seq_file.h>
   4 #include <linux/export.h>
   5 #include <linux/suspend.h>
   6 #include <linux/bcd.h>
   7 #include <linux/acpi.h>
   8 #include <linux/uaccess.h>
   9
  10 #include "sleep.h"
  11 #include "internal.h"
  12
  13 #define _COMPONENT              ACPI_SYSTEM_COMPONENT
  14
  15 /*
  16  * this file provides support for:
  17  * /proc/acpi/wakeup
  18  */
  19
  20 ACPI_MODULE_NAME("sleep")
  21
  22 static int
  23 acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
  24 {
  25         struct acpi_device *dev, *tmp;
  26
  27         seq_printf(seq, "Device\tS-state\t  Status   Sysfs node\n");
  28
  29         mutex_lock(&acpi_device_lock);
  30         list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
  31                                  wakeup_list) {
  32                 struct acpi_device_physical_node *entry;
  33
  34                 if (!dev->wakeup.flags.valid)
  35                         continue;
  36
  37                 seq_printf(seq, "%s\t  S%d\t",
  38                            dev->pnp.bus_id,
  39                            (u32) dev->wakeup.sleep_state);
  40
  41                 mutex_lock(&dev->physical_node_lock);
  42
  43                 if (!dev->physical_node_count) {
  44                         seq_printf(seq, "%c%-8s\n",
  45                                 dev->wakeup.flags.valid ? '*' : ' ',
  46                                 device_may_wakeup(&dev->dev) ?
  47                                         "enabled" : "disabled");
  48                 } else {
  49                         struct device *ldev;
  50                         list_for_each_entry(entry, &dev->physical_node_list,
  51                                         node) {
  52                                 ldev = get_device(entry->dev);
  53                                 if (!ldev)
  54                                         continue;
  55
  56                                 if (&entry->node !=
  57                                                 dev->physical_node_list.next)
  58                                         seq_printf(seq, "\t\t");
  59
  60                                 seq_printf(seq, "%c%-8s  %s:%s\n",
  61                                         dev->wakeup.flags.valid ? '*' : ' ',
  62                                         (device_may_wakeup(&dev->dev) ||
  63                                         device_may_wakeup(ldev)) ?
  64                                         "enabled" : "disabled",
  65                                         ldev->bus ? ldev->bus->name :
  66                                         "no-bus", dev_name(ldev));
  67                                 put_device(ldev);
  68                         }
  69                 }
  70
  71                 mutex_unlock(&dev->physical_node_lock);
  72         }
  73         mutex_unlock(&acpi_device_lock);
  74         return 0;
  75 }
  76
  77 static void physical_device_enable_wakeup(struct acpi_device *adev)
  78 {
  79         struct acpi_device_physical_node *entry;
  80
  81         mutex_lock(&adev->physical_node_lock);
  82
  83         list_for_each_entry(entry,
  84                 &adev->physical_node_list, node)
  85                 if (entry->dev && device_can_wakeup(entry->dev)) {
  86                         bool enable = !device_may_wakeup(entry->dev);
  87                         device_set_wakeup_enable(entry->dev, enable);
  88                 }
  89
  90         mutex_unlock(&adev->physical_node_lock);
  91 }
  92
  93 static ssize_t
  94 acpi_system_write_wakeup_device(struct file *file,
  95                                 const char __user * buffer,
  96                                 size_t count, loff_t * ppos)
  97 {
  98         struct acpi_device *dev, *tmp;
  99         char strbuf[5];
 100         char str[5] = "";
 101
 102         if (count > 4)
 103                 count = 4;
 104
 105         if (copy_from_user(strbuf, buffer, count))
 106                 return -EFAULT;
 107         strbuf[count] = '\0';
 108         sscanf(strbuf, "%s", str);
 109
 110         mutex_lock(&acpi_device_lock);
 111         list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
 112                                  wakeup_list) {
 113                 if (!dev->wakeup.flags.valid)
 114                         continue;
 115
 116                 if (!strncmp(dev->pnp.bus_id, str, 4)) {
 117                         if (device_can_wakeup(&dev->dev)) {
 118                                 bool enable = !device_may_wakeup(&dev->dev);
 119                                 device_set_wakeup_enable(&dev->dev, enable);
 120                         } else {
 121                                 physical_device_enable_wakeup(dev);
 122                         }
 123                         break;
 124                 }
 125         }
 126         mutex_unlock(&acpi_device_lock);
 127         return count;
 128 }
 129
 130 static int
 131 acpi_system_wakeup_device_open_fs(struct inode *inode, struct file *file)
 132 {
 133         return single_open(file, acpi_system_wakeup_device_seq_show,
 134                            PDE_DATA(inode));
 135 }
 136
 137 static const struct proc_ops acpi_system_wakeup_device_proc_ops = {
 138         .proc_open      = acpi_system_wakeup_device_open_fs,
 139         .proc_read      = seq_read,
 140         .proc_write     = acpi_system_write_wakeup_device,
 141         .proc_lseek     = seq_lseek,
 142         .proc_release   = single_release,
 143 };
 144
 145 void __init acpi_sleep_proc_init(void)
 146 {
 147         /* 'wakeup device' [R/W] */
 148         proc_create("wakeup", S_IFREG | S_IRUGO | S_IWUSR,
 149                     acpi_root_dir, &acpi_system_wakeup_device_proc_ops);
 150 }