drivers/soc/litex: Use devm_register_restart_handler()

Use device life-cycle managed register function to simplify probe error
path and eliminate need for explicit remove function.

Signed-off-by: Andrew Davis <afd@ti.com>
Reviewed-by: Gabriel Somlo <gsomlo@gmail.com>
Link: https://lore.kernel.org/all/20240123164443.394642-3-afd@ti.com
Signed-off-by: Gabriel Somlo <gsomlo@gmail.com>

drivers/soc/litex/litex_soc_ctrl.c

@@ -69,14 +69,11 @@ static int litex_check_csr_access(void __iomem *reg_addr)
 
 struct litex_soc_ctrl_device {
 	void __iomem *base;
-	struct notifier_block reset_nb;
 };
 
-static int litex_reset_handler(struct notifier_block *this, unsigned long mode,
-			       void *cmd)
+static int litex_reset_handler(struct sys_off_data *data)
 {
-	struct litex_soc_ctrl_device *soc_ctrl_dev =
-		container_of(this, struct litex_soc_ctrl_device, reset_nb);
+	struct litex_soc_ctrl_device *soc_ctrl_dev = data->cb_data;
 
 	litex_write32(soc_ctrl_dev->base + RESET_REG_OFF, RESET_REG_VALUE);
 	return NOTIFY_DONE;
@@ -105,11 +102,9 @@ static int litex_soc_ctrl_probe(struct platform_device *pdev)
 	if (error)
 		return error;
 
-	platform_set_drvdata(pdev, soc_ctrl_dev);
-
-	soc_ctrl_dev->reset_nb.notifier_call = litex_reset_handler;
-	soc_ctrl_dev->reset_nb.priority = 128;
-	error = register_restart_handler(&soc_ctrl_dev->reset_nb);
+	error = devm_register_restart_handler(&pdev->dev,
+					      litex_reset_handler,
+					      soc_ctrl_dev);
 	if (error) {
 		dev_warn(&pdev->dev, "cannot register restart handler: %d\n",
 			 error);
@@ -118,20 +113,12 @@ static int litex_soc_ctrl_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static void litex_soc_ctrl_remove(struct platform_device *pdev)
-{
-	struct litex_soc_ctrl_device *soc_ctrl_dev = platform_get_drvdata(pdev);
-
-	unregister_restart_handler(&soc_ctrl_dev->reset_nb);
-}
-
 static struct platform_driver litex_soc_ctrl_driver = {
 	.driver = {
 		.name = "litex-soc-controller",
 		.of_match_table = litex_soc_ctrl_of_match,
 	},
 	.probe = litex_soc_ctrl_probe,
-	.remove = litex_soc_ctrl_remove,
 };
 
 module_platform_driver(litex_soc_ctrl_driver);