[PATCH 04/14] drivers/firmware/sdei: Rework sdei_init()

[Gavin Shan]

This reworks sdei_init()

   * The function follows the steps in sequence: check ACPI existence,
     register platform device, register platform driver.
   * The corresponding error numbers are returned in failing paths.
   * The platform device is deleted if the driver can't be registered.

Signed-off-by: Gavin Shan <gshan at redhat.com>
---
 drivers/firmware/arm_sdei.c | 28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c
index 35a319e7e1e6..7e7b26b1f91b 100644
--- a/drivers/firmware/arm_sdei.c
+++ b/drivers/firmware/arm_sdei.c
@@ -1058,7 +1058,7 @@ static bool __init sdei_present_acpi(void)
 	acpi_status status;
 	struct acpi_table_header *sdei_table_header;
 
-	if (acpi_disabled)
+	if (!IS_ENABLED(CONFIG_ACPI) || acpi_disabled)
 		return false;
 
 	status = acpi_get_table(ACPI_SIG_SDEI, 0, &sdei_table_header);
@@ -1077,19 +1077,27 @@ static bool __init sdei_present_acpi(void)
 
 static int __init sdei_init(void)
 {
-	int ret = platform_driver_register(&sdei_driver);
+	struct platform_device *pdev;
+	int ret;
 
-	if (!ret && sdei_present_acpi()) {
-		struct platform_device *pdev;
+	if (!sdei_present_acpi())
+		return -EPERM;
 
-		pdev = platform_device_register_simple(sdei_driver.driver.name,
-						       0, NULL, 0);
-		if (IS_ERR(pdev))
-			pr_info("Failed to register ACPI:SDEI platform device %ld\n",
-				PTR_ERR(pdev));
+	pdev = platform_device_register_simple(sdei_driver.driver.name,
+					       0, NULL, 0);
+	if (IS_ERR(pdev)) {
+		pr_info("Failed to register ACPI:SDEI platform device %ld\n",
+			PTR_ERR(pdev));
+		return -ENOMEM;
 	}
 
-	return ret;
+	ret = platform_driver_register(&sdei_driver);
+	if (ret) {
+		platform_device_del(pdev);
+		return ret;
+	}
+
+	return 0;
 }
 
 /*
-- 
2.23.0