[PATCH] extcon: rt8973a: synchronize work teardown

[Hongyan Xu]

Nested IRQ handlers schedule irq_work and probe queues wq_detcable, but
remove only deletes the regmap IRQ chip. Either work item can outlive
info. Probe failures after the IRQ chip is installed also lack matching
chip cleanup.

Manage the IRQ chip and both work items with devres, and request nested
IRQs after their callback dependencies are initialized. Devres teardown
then stops the IRQ producers before cancelling the work.

Signed-off-by: Hongyan Xu <getshell@xxxxxxxxxx>
---
 drivers/extcon/extcon-rt8973a.c | 60 ++++++++++++++++-----------------
 1 file changed, 30 insertions(+), 30 deletions(-)

diff --git a/drivers/extcon/extcon-rt8973a.c b/drivers/extcon/extcon-rt8973a.c
index 19bb49f..df8ccdd 100644
--- a/drivers/extcon/extcon-rt8973a.c
+++ b/drivers/extcon/extcon-rt8973a.c
@@ -6,6 +6,7 @@
  * Author: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
  */
 
+#include <linux/devm-helpers.h>
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/input.h>
@@ -572,8 +573,6 @@ static int rt8973a_muic_i2c_probe(struct i2c_client *i2c)
 
 	mutex_init(&info->mutex);
 
-	INIT_WORK(&info->irq_work, rt8973a_muic_irq_work);
-
 	info->regmap = devm_regmap_init_i2c(i2c, &rt8973a_muic_regmap_config);
 	if (IS_ERR(info->regmap)) {
 		ret = PTR_ERR(info->regmap);
@@ -584,14 +583,41 @@ static int rt8973a_muic_i2c_probe(struct i2c_client *i2c)
 
 	/* Support irq domain for RT8973A MUIC device */
 	irq_flags = IRQF_TRIGGER_FALLING | IRQF_ONESHOT | IRQF_SHARED;
-	ret = regmap_add_irq_chip(info->regmap, info->irq, irq_flags, 0,
-				  &rt8973a_muic_irq_chip, &info->irq_data);
+	ret = devm_regmap_add_irq_chip(info->dev, info->regmap, info->irq,
+				       irq_flags, 0, &rt8973a_muic_irq_chip,
+				       &info->irq_data);
 	if (ret != 0) {
 		dev_err(info->dev, "failed to add irq_chip (irq:%d, err:%d)\n",
 				    info->irq, ret);
 		return ret;
 	}
 
+	/* Allocate extcon device */
+	info->edev = devm_extcon_dev_allocate(info->dev, rt8973a_extcon_cable);
+	if (IS_ERR(info->edev)) {
+		dev_err(info->dev, "failed to allocate memory for extcon\n");
+		return -ENOMEM;
+	}
+
+	/* Register extcon device */
+	ret = devm_extcon_dev_register(info->dev, info->edev);
+	if (ret) {
+		dev_err(info->dev, "failed to register extcon device\n");
+		return ret;
+	}
+
+	ret = devm_work_autocancel(info->dev, &info->irq_work,
+				   rt8973a_muic_irq_work);
+	if (ret)
+		return ret;
+	ret = devm_delayed_work_autocancel(info->dev, &info->wq_detcable,
+					   rt8973a_muic_detect_cable_wq);
+	if (ret)
+		return ret;
+
+	/* Initialize RT8973A device and print vendor id and version id */
+	rt8973a_init_dev_type(info);
+
 	for (i = 0; i < info->num_muic_irqs; i++) {
 		struct muic_irq *muic_irq = &info->muic_irqs[i];
 		int virq = 0;
@@ -613,20 +639,6 @@ static int rt8973a_muic_i2c_probe(struct i2c_client *i2c)
 		}
 	}
 
-	/* Allocate extcon device */
-	info->edev = devm_extcon_dev_allocate(info->dev, rt8973a_extcon_cable);
-	if (IS_ERR(info->edev)) {
-		dev_err(info->dev, "failed to allocate memory for extcon\n");
-		return -ENOMEM;
-	}
-
-	/* Register extcon device */
-	ret = devm_extcon_dev_register(info->dev, info->edev);
-	if (ret) {
-		dev_err(info->dev, "failed to register extcon device\n");
-		return ret;
-	}
-
 	/*
 	 * Detect accessory after completing the initialization of platform
 	 *
@@ -635,23 +647,12 @@ static int rt8973a_muic_i2c_probe(struct i2c_client *i2c)
 	 * After completing the booting of platform, the extcon provider
 	 * driver should notify cable state to upper layer.
 	 */
-	INIT_DELAYED_WORK(&info->wq_detcable, rt8973a_muic_detect_cable_wq);
 	queue_delayed_work(system_power_efficient_wq, &info->wq_detcable,
 			msecs_to_jiffies(DELAY_MS_DEFAULT));
 
-	/* Initialize RT8973A device and print vendor id and version id */
-	rt8973a_init_dev_type(info);
-
 	return 0;
 }
 
-static void rt8973a_muic_i2c_remove(struct i2c_client *i2c)
-{
-	struct rt8973a_muic_info *info = i2c_get_clientdata(i2c);
-
-	regmap_del_irq_chip(info->irq, info->irq_data);
-}
-
 static const struct of_device_id rt8973a_dt_match[] = {
 	{ .compatible = "richtek,rt8973a-muic" },
 	{ },
@@ -696,7 +697,6 @@ static struct i2c_driver rt8973a_muic_i2c_driver = {
 		.of_match_table = rt8973a_dt_match,
 	},
 	.probe = rt8973a_muic_i2c_probe,
-	.remove	= rt8973a_muic_i2c_remove,
 	.id_table = rt8973a_i2c_id,
 };
 
-- 
2.50.1.windows.1