regulator: qcom_spmi-regulator: Clean-up by using managed work init

Few drivers implement remove call-back only for ensuring a delayed
work gets cancelled prior driver removal. Clean-up these by switching
to use devm_delayed_work_autocancel() instead.

Additionally, this helps avoiding mixing devm and manual resource
management and cleans up a (theoretical?) bug where devm managed
over-current IRQ might schedule a new work item after wq was cleaned
at remove().

This change is compile-tested only. All testing is appreciated.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/3bd35bb43257f4bf5b99f75d207ed5e1e08d1d38.1616506559.git.matti.vaittinen@fi.rohmeurope.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/regulator/qcom_spmi-regulator.c

@@ -5,6 +5,7 @@
 
 #include <linux/module.h>
 #include <linux/delay.h>
+#include <linux/devm-helpers.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/interrupt.h>
@@ -1842,7 +1843,10 @@ static int spmi_regulator_of_parse(struct device_node *node,
 			return ret;
 		}
 
-		INIT_DELAYED_WORK(&vreg->ocp_work, spmi_regulator_vs_ocp_work);
+		ret = devm_delayed_work_autocancel(dev, &vreg->ocp_work,
+						   spmi_regulator_vs_ocp_work);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
@@ -2157,10 +2161,8 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 		vreg->regmap = regmap;
 		if (reg->ocp) {
 			vreg->ocp_irq = platform_get_irq_byname(pdev, reg->ocp);
-			if (vreg->ocp_irq < 0) {
-				ret = vreg->ocp_irq;
-				goto err;
-			}
+			if (vreg->ocp_irq < 0)
+				return vreg->ocp_irq;
 		}
 		vreg->desc.id = -1;
 		vreg->desc.owner = THIS_MODULE;
@@ -2203,8 +2205,7 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 		rdev = devm_regulator_register(dev, &vreg->desc, &config);
 		if (IS_ERR(rdev)) {
 			dev_err(dev, "failed to register %s\n", name);
-			ret = PTR_ERR(rdev);
-			goto err;
+			return PTR_ERR(rdev);
 		}
 
 		INIT_LIST_HEAD(&vreg->node);
@@ -2212,24 +2213,6 @@ static int qcom_spmi_regulator_probe(struct platform_device *pdev)
 	}
 
 	return 0;
-
-err:
-	list_for_each_entry(vreg, vreg_list, node)
-		if (vreg->ocp_irq)
-			cancel_delayed_work_sync(&vreg->ocp_work);
-	return ret;
-}
-
-static int qcom_spmi_regulator_remove(struct platform_device *pdev)
-{
-	struct spmi_regulator *vreg;
-	struct list_head *vreg_list = platform_get_drvdata(pdev);
-
-	list_for_each_entry(vreg, vreg_list, node)
-		if (vreg->ocp_irq)
-			cancel_delayed_work_sync(&vreg->ocp_work);
-
-	return 0;
 }
 
 static struct platform_driver qcom_spmi_regulator_driver = {
@@ -2238,7 +2221,6 @@ static struct platform_driver qcom_spmi_regulator_driver = {
 		.of_match_table = qcom_spmi_regulator_match,
 	},
 	.probe		= qcom_spmi_regulator_probe,
-	.remove		= qcom_spmi_regulator_remove,
 };
 module_platform_driver(qcom_spmi_regulator_driver);