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