regulator: dummy: convert to use the faux device interface

The dummy regulator driver does not need to create a platform device, it
only did so because it was simple to do.  Change it over to use the
faux bus instead as this is NOT a real platform device, and it makes
the code even smaller than before.

Reviewed-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/2025021027-outclass-stress-59dd@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/regulator/dummy.c b/drivers/regulator/dummy.c
index 5b9b9e4e762d52151847bb1880377d51b04eeb9d..e5197ec7234d01518b26844c555f3900a4ee5750 100644 (file)
--- a/drivers/regulator/dummy.c
+++ b/drivers/regulator/dummy.c
@@ -13,7 +13,7 @@
 
 #include <linux/err.h>
 #include <linux/export.h>
-#include <linux/platform_device.h>
+#include <linux/device/faux.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/machine.h>
 
@@ -37,15 +37,15 @@ static const struct regulator_desc dummy_desc = {
        .ops = &dummy_ops,
 };
 
-static int dummy_regulator_probe(struct platform_device *pdev)
+static int dummy_regulator_probe(struct faux_device *fdev)
 {
        struct regulator_config config = { };
        int ret;
 
-       config.dev = &pdev->dev;
+       config.dev = &fdev->dev;
        config.init_data = &dummy_initdata;
 
-       dummy_regulator_rdev = devm_regulator_register(&pdev->dev, &dummy_desc,
+       dummy_regulator_rdev = devm_regulator_register(&fdev->dev, &dummy_desc,
                                                       &config);
        if (IS_ERR(dummy_regulator_rdev)) {
                ret = PTR_ERR(dummy_regulator_rdev);
@@ -56,36 +56,17 @@ static int dummy_regulator_probe(struct platform_device *pdev)
        return 0;
 }
 
-static struct platform_driver dummy_regulator_driver = {
-       .probe          = dummy_regulator_probe,
-       .driver         = {
-               .name           = "reg-dummy",
-               .probe_type     = PROBE_PREFER_ASYNCHRONOUS,
-       },
+struct faux_device_ops dummy_regulator_driver = {
+       .probe = dummy_regulator_probe,
 };
 
-static struct platform_device *dummy_pdev;
+static struct faux_device *dummy_fdev;
 
 void __init regulator_dummy_init(void)
 {
-       int ret;
-
-       dummy_pdev = platform_device_alloc("reg-dummy", -1);
-       if (!dummy_pdev) {
+       dummy_fdev = faux_device_create("reg-dummy", NULL, &dummy_regulator_driver);
+       if (!dummy_fdev) {
                pr_err("Failed to allocate dummy regulator device\n");
                return;
        }
-
-       ret = platform_device_add(dummy_pdev);
-       if (ret != 0) {
-               pr_err("Failed to register dummy regulator device: %d\n", ret);
-               platform_device_put(dummy_pdev);
-               return;
-       }
-
-       ret = platform_driver_register(&dummy_regulator_driver);
-       if (ret != 0) {
-               pr_err("Failed to register dummy regulator driver: %d\n", ret);
-               platform_device_unregister(dummy_pdev);
-       }
 }