[PATCH v1] Input: atlas - convert ACPI driver to a platform one

[Rafael J. Wysocki]

From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx>

In all cases in which a struct acpi_driver is used for binding a driver
to an ACPI device object, a corresponding platform device is created by
the ACPI core and that device is regarded as a proper representation of
underlying hardware.  Accordingly, a struct platform_driver should be
used by driver code to bind to that device.  There are multiple reasons
why drivers should not bind directly to ACPI device objects [1].

Overall, it is better to bind drivers to platform devices than to their
ACPI companions, so convert the ACPI Atlas button driver to a platform
one.

While this is not expected to alter functionality, it changes sysfs
layout and so it will be visible to user space.

Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/ [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
 drivers/input/misc/atlas_btns.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/input/misc/atlas_btns.c b/drivers/input/misc/atlas_btns.c
index 5b9be2957746..47b31725e850 100644
--- a/drivers/input/misc/atlas_btns.c
+++ b/drivers/input/misc/atlas_btns.c
@@ -14,6 +14,7 @@
 #include <linux/input.h>
 #include <linux/types.h>
 #include <linux/acpi.h>
+#include <linux/platform_device.h>
 #include <linux/uaccess.h>
 
 #define ACPI_ATLAS_NAME		"Atlas ACPI"
@@ -57,8 +58,9 @@ static acpi_status acpi_atlas_button_handler(u32 function,
 	return status;
 }
 
-static int atlas_acpi_button_add(struct acpi_device *device)
+static int atlas_acpi_button_probe(struct platform_device *pdev)
 {
+	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 	acpi_status status;
 	int i;
 	int err;
@@ -106,8 +108,9 @@ static int atlas_acpi_button_add(struct acpi_device *device)
 	return err;
 }
 
-static void atlas_acpi_button_remove(struct acpi_device *device)
+static void atlas_acpi_button_remove(struct platform_device *pdev)
 {
+	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
 	acpi_status status;
 
 	status = acpi_remove_address_space_handler(device->handle,
@@ -124,16 +127,15 @@ static const struct acpi_device_id atlas_device_ids[] = {
 };
 MODULE_DEVICE_TABLE(acpi, atlas_device_ids);
 
-static struct acpi_driver atlas_acpi_driver = {
-	.name	= ACPI_ATLAS_NAME,
-	.class	= ACPI_ATLAS_CLASS,
-	.ids	= atlas_device_ids,
-	.ops	= {
-		.add	= atlas_acpi_button_add,
-		.remove	= atlas_acpi_button_remove,
+static struct platform_driver atlas_acpi_driver = {
+	.probe = atlas_acpi_button_probe,
+	.remove = atlas_acpi_button_remove,
+	.driver = {
+		.name = ACPI_ATLAS_NAME,
+		.acpi_match_table = atlas_device_ids,
 	},
 };
-module_acpi_driver(atlas_acpi_driver);
+module_platform_driver(atlas_acpi_driver);
 
 MODULE_AUTHOR("Jaya Kumar");
 MODULE_LICENSE("GPL");
-- 
2.51.0