platform/x86: dell-pc: Transition to faux device

Use a faux device parent for registering the platform_profile instead of
a "fake" platform device.

The faux bus is a minimalistic, single driver bus designed for this
purpose.

Signed-off-by: Kurt Borja <kuurtb@gmail.com>
Link: https://lore.kernel.org/r/20250411-dell-faux-v1-3-ea1f1c929b7e@gmail.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/dell/dell-pc.c b/drivers/platform/x86/dell/dell-pc.c
index 7949249..48cc751 100644 (file)
--- a/drivers/platform/x86/dell/dell-pc.c
+++ b/drivers/platform/x86/dell/dell-pc.c
@@ -13,18 +13,18 @@
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/bits.h>
+#include <linux/device/faux.h>
 #include <linux/dmi.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_profile.h>
-#include <linux/platform_device.h>
 #include <linux/slab.h>
 
 #include "dell-smbios.h"
 
-static struct platform_device *platform_device;
+static struct faux_device *dell_pc_fdev;
 static int supported_modes;
 
 static const struct dmi_system_id dell_device_table[] __initconst = {
@@ -246,7 +246,7 @@ static const struct platform_profile_ops dell_pc_platform_profile_ops = {
        .profile_set = thermal_platform_profile_set,
 };
 
-static int thermal_init(void)
+static int dell_pc_faux_probe(struct faux_device *fdev)
 {
        struct device *ppdev;
        int ret;
@@ -258,51 +258,31 @@ static int thermal_init(void)
        if (ret < 0)
                return ret;
 
-       platform_device = platform_device_register_simple("dell-pc", PLATFORM_DEVID_NONE, NULL, 0);
-       if (IS_ERR(platform_device))
-               return PTR_ERR(platform_device);
+       ppdev = devm_platform_profile_register(&fdev->dev, "dell-pc", NULL,
+                                              &dell_pc_platform_profile_ops);
 
-       ppdev = devm_platform_profile_register(&platform_device->dev, "dell-pc",
-                                              NULL, &dell_pc_platform_profile_ops);
-       if (IS_ERR(ppdev)) {
-               ret = PTR_ERR(ppdev);
-               goto cleanup_platform_device;
-       }
-
-       return 0;
-
-cleanup_platform_device:
-       platform_device_unregister(platform_device);
-
-       return ret;
+       return PTR_ERR_OR_ZERO(ppdev);
 }
 
-static void thermal_cleanup(void)
-{
-       platform_device_unregister(platform_device);
-}
+static const struct faux_device_ops dell_pc_faux_ops = {
+       .probe = dell_pc_faux_probe,
+};
 
 static int __init dell_init(void)
 {
-       int ret;
-
        if (!dmi_check_system(dell_device_table))
                return -ENODEV;
 
-       ret = thermal_init();
-       if (ret)
-               goto fail_thermal;
+       dell_pc_fdev = faux_device_create("dell-pc", NULL, &dell_pc_faux_ops);
+       if (!dell_pc_fdev)
+               return -ENODEV;
 
        return 0;
-
-fail_thermal:
-       thermal_cleanup();
-       return ret;
 }
 
 static void __exit dell_exit(void)
 {
-       thermal_cleanup();
+       faux_device_destroy(dell_pc_fdev);
 }
 
 module_init(dell_init);