// SPDX-License-Identifier: GPL-2.0
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/string_choices.h>
#include <linux/suspend.h>
#include <linux/bcd.h>
#include <linux/acpi.h>
#include <linux/uaccess.h>

#include "sleep.h"
#include "internal.h"

/*
 * this file provides support for:
 * /proc/acpi/wakeup
 */

static int
acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset)
{
        struct acpi_device *dev, *tmp;

        seq_printf(seq, "Device\tS-state\t  Status   Sysfs node\n");

        mutex_lock(&acpi_device_lock);
        list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
                                 wakeup_list) {
                struct acpi_device_physical_node *entry;

                if (!dev->wakeup.flags.valid)
                        continue;

                seq_printf(seq, "%s\t  S%llu\t",
                           dev->pnp.bus_id,
                           dev->wakeup.sleep_state);

                mutex_lock(&dev->physical_node_lock);

                if (!dev->physical_node_count) {
                        seq_printf(seq, "%c%-8s\n",
                                dev->wakeup.flags.valid ? '*' : ' ',
                                str_enabled_disabled(device_may_wakeup(&dev->dev)));
                } else {
                        struct device *ldev;
                        list_for_each_entry(entry, &dev->physical_node_list,
                                        node) {
                                ldev = get_device(entry->dev);
                                if (!ldev)
                                        continue;

                                if (&entry->node !=
                                                dev->physical_node_list.next)
                                        seq_printf(seq, "\t\t");

                                seq_printf(seq, "%c%-8s  %s:%s\n",
                                        dev->wakeup.flags.valid ? '*' : ' ',
                                        str_enabled_disabled(device_may_wakeup(ldev) ||
                                                             device_may_wakeup(&dev->dev)),
                                        ldev->bus ? ldev->bus->name :
                                        "no-bus", dev_name(ldev));
                                put_device(ldev);
                        }
                }

                mutex_unlock(&dev->physical_node_lock);
        }
        mutex_unlock(&acpi_device_lock);
        return 0;
}

static void physical_device_enable_wakeup(struct acpi_device *adev)
{
        struct acpi_device_physical_node *entry;

        mutex_lock(&adev->physical_node_lock);

        list_for_each_entry(entry,
                &adev->physical_node_list, node)
                if (entry->dev && device_can_wakeup(entry->dev)) {
                        bool enable = !device_may_wakeup(entry->dev);
                        device_set_wakeup_enable(entry->dev, enable);
                }

        mutex_unlock(&adev->physical_node_lock);
}

static ssize_t
acpi_system_write_wakeup_device(struct file *file,
                                const char __user * buffer,
                                size_t count, loff_t * ppos)
{
        struct acpi_device *dev, *tmp;
        char strbuf[5];
        char str[5] = "";

        if (count > 4)
                count = 4;

        if (copy_from_user(strbuf, buffer, count))
                return -EFAULT;
        strbuf[count] = '\0';
        sscanf(strbuf, "%s", str);

        mutex_lock(&acpi_device_lock);
        list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
                                 wakeup_list) {
                if (!dev->wakeup.flags.valid)
                        continue;

                if (!strncmp(dev->pnp.bus_id, str, 4)) {
                        if (device_can_wakeup(&dev->dev)) {
                                bool enable = !device_may_wakeup(&dev->dev);
                                device_set_wakeup_enable(&dev->dev, enable);
                        } else {
                                physical_device_enable_wakeup(dev);
                        }
                        break;
                }
        }
        mutex_unlock(&acpi_device_lock);
        return count;
}

static int
acpi_system_wakeup_device_open_fs(struct inode *inode, struct file *file)
{
        return single_open(file, acpi_system_wakeup_device_seq_show,
                           pde_data(inode));
}

static const struct proc_ops acpi_system_wakeup_device_proc_ops = {
        .proc_open      = acpi_system_wakeup_device_open_fs,
        .proc_read      = seq_read,
        .proc_write     = acpi_system_write_wakeup_device,
        .proc_lseek     = seq_lseek,
        .proc_release   = single_release,
};

void __init acpi_sleep_proc_init(void)
{
        /* 'wakeup device' [R/W] */
        proc_create("wakeup", 0644, acpi_root_dir, &acpi_system_wakeup_device_proc_ops);
}