add new system file

hc

2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c

 kernel/drivers/acpi/acpi_platform.c
..
..
@@ -1,3 +1,4 @@
1
+// SPDX-License-Identifier: GPL-2.0-only
1
2
 /*
2
3
  * ACPI support for platform bus type.
3
4
  *
..
..
@@ -5,10 +6,6 @@
5
6
  * Authors: Mika Westerberg <mika.westerberg@linux.intel.com>
6
7
  *          Mathias Nyman <mathias.nyman@linux.intel.com>
7
8
  *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8
- *
9
- * This program is free software; you can redistribute it and/or modify
10
- * it under the terms of the GNU General Public License version 2 as
11
- * published by the Free Software Foundation.
12
9
  */
13
10
 
14
11
 #include <linux/acpi.h>
..
..
@@ -22,8 +19,6 @@
22
19
 
23
20
 #include "internal.h"
24
21
 
25
-ACPI_MODULE_NAME("platform");
26
-
27
22
 static const struct acpi_device_id forbidden_id_list[] = {
28
23
 	{"PNP0000",  0},	/* PIC */
29
24
 	{"PNP0100",  0},	/* Timer */
..
..
@@ -32,6 +27,44 @@
32
27
 	{"ACPI000A", 0},	/* IOAPIC */
33
28
 	{"SMB0001",  0},	/* ACPI SMBUS virtual device */
34
29
 	{"", 0},
30
+};
31
+
32
+static struct platform_device *acpi_platform_device_find_by_companion(struct acpi_device *adev)
33
+{
34
+	struct device *dev;
35
+
36
+	dev = bus_find_device_by_acpi_dev(&platform_bus_type, adev);
37
+	return dev ? to_platform_device(dev) : NULL;
38
+}
39
+
40
+static int acpi_platform_device_remove_notify(struct notifier_block *nb,
41
+					      unsigned long value, void *arg)
42
+{
43
+	struct acpi_device *adev = arg;
44
+	struct platform_device *pdev;
45
+
46
+	switch (value) {
47
+	case ACPI_RECONFIG_DEVICE_ADD:
48
+		/* Nothing to do here */
49
+		break;
50
+	case ACPI_RECONFIG_DEVICE_REMOVE:
51
+		if (!acpi_device_enumerated(adev))
52
+			break;
53
+
54
+		pdev = acpi_platform_device_find_by_companion(adev);
55
+		if (!pdev)
56
+			break;
57
+
58
+		platform_device_unregister(pdev);
59
+		put_device(&pdev->dev);
60
+		break;
61
+	}
62
+
63
+	return NOTIFY_OK;
64
+}
65
+
66
+static struct notifier_block acpi_platform_notifier = {
67
+	.notifier_call = acpi_platform_device_remove_notify,
35
68
 };
36
69
 
37
70
 static void acpi_platform_fill_resource(struct acpi_device *adev,
..
..
@@ -133,3 +166,8 @@
133
166
 	return pdev;
134
167
 }
135
168
 EXPORT_SYMBOL_GPL(acpi_create_platform_device);
169
+
170
+void __init acpi_platform_init(void)
171
+{
172
+	acpi_reconfig_notifier_register(&acpi_platform_notifier);
173
+}