[PATCH v3] hwmon: (sht15) Stop deferred work before releasing its resources

[Myeonghun Pak <mhun512@gmail.com>]

The IRQ handler and regulator notifier can leave work pending after a
measurement or notification completes. Neither work item is drained before
its resources are released on removal or probe failure.

Disable read_work before freeing the IRQ, since the worker can re-enable
it. Use request_irq()/free_irq() for explicit teardown. Unregister the
regulator notifier before cancelling update_supply_work and disabling the
regulator. Apply the same ordering to probe failures.

Fixes: 251eb40f5ccd ("hwmon: sht15 humidity sensor driver")
Assisted-by: LLM
Co-developed-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Ijae Kim <ae878000@gmail.com>
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
---
Compile-tested with GCC 15.2.0, W=1 (x86_64). No runtime testing.

Changes in v3:
- Drop IRQF_NO_AUTOEN and IRQ caching; preserve the original initialization.
- Keep request_irq()/free_irq() and work synchronization.

Changes in v2:
- Switch to request_irq()/free_irq().
- Add IRQF_NO_AUTOEN and IRQ caching.

 drivers/hwmon/sht15.c | 22 ++++++++++++++--------
 1 file changed, 14 insertions(+), 8 deletions(-)

diff --git a/drivers/hwmon/sht15.c b/drivers/hwmon/sht15.c
index 7bb2105d1ae223e7131ba4cc0523e4e074e01302..48d93c61345c1d4a00b0edd2fc452161ac90db9e 100644
--- a/drivers/hwmon/sht15.c
+++ b/drivers/hwmon/sht15.c
@@ -31,6 +31,7 @@
 #include <linux/bitrev.h>
 #include <linux/gpio/consumer.h>
 #include <linux/of.h>
+#include <linux/workqueue.h>
 
 /* Commands */
 #define SHT15_MEASURE_TEMP		0x03
@@ -976,25 +977,22 @@ static int sht15_probe(struct platform_device *pdev)
 		goto err_release_reg;
 	}
 
-	ret = devm_request_irq(&pdev->dev, gpiod_to_irq(data->data),
-			       sht15_interrupt_fired,
-			       IRQF_TRIGGER_FALLING,
-			       "sht15 data",
-			       data);
+	ret = request_irq(gpiod_to_irq(data->data), sht15_interrupt_fired,
+			  IRQF_TRIGGER_FALLING, "sht15 data", data);
 	if (ret)
 		goto err_release_reg;
 	disable_irq_nosync(gpiod_to_irq(data->data));
 	ret = sht15_connection_reset(data);
 	if (ret)
-		goto err_release_reg;
+		goto err_free_irq;
 	ret = sht15_soft_reset(data);
 	if (ret)
-		goto err_release_reg;
+		goto err_free_irq;
 
 	ret = sysfs_create_group(&pdev->dev.kobj, &sht15_attr_group);
 	if (ret) {
 		dev_err(&pdev->dev, "sysfs create failed\n");
-		goto err_release_reg;
+		goto err_free_irq;
 	}
 
 	data->hwmon_dev = hwmon_device_register(data->dev);
@@ -1007,9 +1005,13 @@ static int sht15_probe(struct platform_device *pdev)
 
 err_release_sysfs_group:
 	sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
+err_free_irq:
+	disable_work_sync(&data->read_work);
+	free_irq(gpiod_to_irq(data->data), data);
 err_release_reg:
 	if (!IS_ERR(data->reg)) {
 		regulator_unregister_notifier(data->reg, &data->nb);
+		cancel_work_sync(&data->update_supply_work);
 		regulator_disable(data->reg);
 	}
 	return ret;
@@ -1023,12 +1025,16 @@ static void sht15_remove(struct platform_device *pdev)
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
 
+	disable_work_sync(&data->read_work);
+	free_irq(gpiod_to_irq(data->data), data);
+
 	ret = sht15_soft_reset(data);
 	if (ret)
 		dev_err(&pdev->dev, "Failed to reset device (%pe)\n", ERR_PTR(ret));
 
 	if (!IS_ERR(data->reg)) {
 		regulator_unregister_notifier(data->reg, &data->nb);
+		cancel_work_sync(&data->update_supply_work);
 		regulator_disable(data->reg);
 	}
 }
-- 
2.53.0