ptp: vmw: Convert to a platform driver

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 PTP VMware ACPI 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/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/12883468.O9o76ZdvQC@rafael.j.wysocki
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/ptp/ptp_vmw.c b/drivers/ptp/ptp_vmw.c
index 20ab05c4daa8ab183b4f439ce2126450fb5232d5..8510121d79d10ec224099e19872d2f048ad1dab9 100644 (file)
--- a/drivers/ptp/ptp_vmw.c
+++ b/drivers/ptp/ptp_vmw.c
@@ -10,6 +10,7 @@
 #include <linux/acpi.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/platform_device.h>
 #include <linux/ptp_clock_kernel.h>
 #include <asm/hypervisor.h>
 #include <asm/vmware.h>
@@ -83,7 +84,7 @@ static struct ptp_clock_info ptp_vmw_clock_info = {
  * ACPI driver ops for VMware "precision clock" virtual device.
  */
 
-static int ptp_vmw_acpi_add(struct acpi_device *device)
+static int ptp_vmw_acpi_probe(struct platform_device *pdev)
 {
        ptp_vmw_clock = ptp_clock_register(&ptp_vmw_clock_info, NULL);
        if (IS_ERR(ptp_vmw_clock)) {
@@ -91,11 +92,11 @@ static int ptp_vmw_acpi_add(struct acpi_device *device)
                return PTR_ERR(ptp_vmw_clock);
        }
 
-       ptp_vmw_acpi_device = device;
+       ptp_vmw_acpi_device = ACPI_COMPANION(&pdev->dev);
        return 0;
 }
 
-static void ptp_vmw_acpi_remove(struct acpi_device *device)
+static void ptp_vmw_acpi_remove(struct platform_device *pdev)
 {
        ptp_clock_unregister(ptp_vmw_clock);
 }
@@ -107,12 +108,12 @@ static const struct acpi_device_id ptp_vmw_acpi_device_ids[] = {
 
 MODULE_DEVICE_TABLE(acpi, ptp_vmw_acpi_device_ids);
 
-static struct acpi_driver ptp_vmw_acpi_driver = {
-       .name = "ptp_vmw",
-       .ids = ptp_vmw_acpi_device_ids,
-       .ops = {
-               .add = ptp_vmw_acpi_add,
-               .remove = ptp_vmw_acpi_remove
+static struct platform_driver ptp_vmw_acpi_driver = {
+       .probe = ptp_vmw_acpi_probe,
+       .remove = ptp_vmw_acpi_remove,
+       .driver = {
+               .name = "ptp_vmw_acpi",
+               .acpi_match_table = ptp_vmw_acpi_device_ids,
        },
 };
 
@@ -120,12 +121,12 @@ static int __init ptp_vmw_init(void)
 {
        if (x86_hyper_type != X86_HYPER_VMWARE)
                return -1;
-       return acpi_bus_register_driver(&ptp_vmw_acpi_driver);
+       return platform_driver_register(&ptp_vmw_acpi_driver);
 }
 
 static void __exit ptp_vmw_exit(void)
 {
-       acpi_bus_unregister_driver(&ptp_vmw_acpi_driver);
+       platform_driver_unregister(&ptp_vmw_acpi_driver);
 }
 
 module_init(ptp_vmw_init);