hwmon: (sch56xx) Use devres functions for watchdog

Use devm_kzalloc()/devm_watchdog_register() for
watchdog registration since it allows us to remove
the sch56xx_watchdog_data struct from the drivers
own data structs.
Remove sch56xx_watchdog_unregister since devres
takes care of that now.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20210508131457.12780-2-W_Armin@gmx.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
[groeck: Dropped unnecessary return; at end of void function]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/sch5627.c

@@ -64,7 +64,6 @@ static const char * const SCH5627_IN_LABELS[SCH5627_NO_IN] = {
 
 struct sch5627_data {
 	unsigned short addr;
-	struct sch56xx_watchdog_data *watchdog;
 	u8 control;
 	u8 temp_max[SCH5627_NO_TEMPS];
 	u8 temp_crit[SCH5627_NO_TEMPS];
@@ -357,16 +356,6 @@ static const struct hwmon_chip_info sch5627_chip_info = {
 	.info = sch5627_info,
 };
 
-static int sch5627_remove(struct platform_device *pdev)
-{
-	struct sch5627_data *data = platform_get_drvdata(pdev);
-
-	if (data->watchdog)
-		sch56xx_watchdog_unregister(data->watchdog);
-
-	return 0;
-}
-
 static int sch5627_probe(struct platform_device *pdev)
 {
 	struct sch5627_data *data;
@@ -460,9 +449,9 @@ static int sch5627_probe(struct platform_device *pdev)
 		return PTR_ERR(hwmon_dev);
 
 	/* Note failing to register the watchdog is not a fatal error */
-	data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr,
-			(build_code << 24) | (build_id << 8) | hwmon_rev,
-			&data->update_lock, 1);
+	sch56xx_watchdog_register(&pdev->dev, data->addr,
+				  (build_code << 24) | (build_id << 8) | hwmon_rev,
+				  &data->update_lock, 1);
 
 	return 0;
 }
@@ -472,7 +461,6 @@ static struct platform_driver sch5627_driver = {
 		.name	= DRVNAME,
 	},
 	.probe		= sch5627_probe,
-	.remove		= sch5627_remove,
 };
 
 module_platform_driver(sch5627_driver);

drivers/hwmon/sch5636.c

@@ -54,7 +54,6 @@ static const u16 SCH5636_REG_FAN_VAL[SCH5636_NO_FANS] = {
 struct sch5636_data {
 	unsigned short addr;
 	struct device *hwmon_dev;
-	struct sch56xx_watchdog_data *watchdog;
 
 	struct mutex update_lock;
 	char valid;			/* !=0 if following fields are valid */
@@ -372,9 +371,6 @@ static int sch5636_remove(struct platform_device *pdev)
 	struct sch5636_data *data = platform_get_drvdata(pdev);
 	int i;
 
-	if (data->watchdog)
-		sch56xx_watchdog_unregister(data->watchdog);
-
 	if (data->hwmon_dev)
 		hwmon_device_unregister(data->hwmon_dev);
 
@@ -495,9 +491,8 @@ static int sch5636_probe(struct platform_device *pdev)
 	}
 
 	/* Note failing to register the watchdog is not a fatal error */
-	data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr,
-					(revision[0] << 8) | revision[1],
-					&data->update_lock, 0);
+	sch56xx_watchdog_register(&pdev->dev, data->addr, (revision[0] << 8) | revision[1],
+				  &data->update_lock, 0);
 
 	return 0;
 

drivers/hwmon/sch56xx-common.c

@@ -378,8 +378,8 @@ static const struct watchdog_ops watchdog_ops = {
 	.set_timeout	= watchdog_set_timeout,
 };
 
-struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
-	u16 addr, u32 revision, struct mutex *io_lock, int check_enabled)
+void sch56xx_watchdog_register(struct device *parent, u16 addr, u32 revision,
+			       struct mutex *io_lock, int check_enabled)
 {
 	struct sch56xx_watchdog_data *data;
 	int err, control, output_enable;
@@ -393,17 +393,17 @@ struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
 	mutex_unlock(io_lock);
 
 	if (control < 0)
-		return NULL;
+		return;
 	if (output_enable < 0)
-		return NULL;
+		return;
 	if (check_enabled && !(output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)) {
 		pr_warn("Watchdog not enabled by BIOS, not registering\n");
-		return NULL;
+		return;
 	}
 
-	data = kzalloc(sizeof(struct sch56xx_watchdog_data), GFP_KERNEL);
+	data = devm_kzalloc(parent, sizeof(struct sch56xx_watchdog_data), GFP_KERNEL);
 	if (!data)
-		return NULL;
+		return;
 
 	data->addr = addr;
 	data->io_lock = io_lock;
@@ -438,24 +438,14 @@ struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
 	data->watchdog_output_enable = output_enable;
 
 	watchdog_set_drvdata(&data->wddev, data);
-	err = watchdog_register_device(&data->wddev);
+	err = devm_watchdog_register_device(parent, &data->wddev);
 	if (err) {
 		pr_err("Registering watchdog chardev: %d\n", err);
-		kfree(data);
-		return NULL;
+		devm_kfree(parent, data);
 	}
-
-	return data;
 }
 EXPORT_SYMBOL(sch56xx_watchdog_register);
 
-void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data)
-{
-	watchdog_unregister_device(&data->wddev);
-	kfree(data);
-}
-EXPORT_SYMBOL(sch56xx_watchdog_unregister);
-
 /*
  * platform dev find, add and remove functions
  */

drivers/hwmon/sch56xx-common.h

@@ -14,6 +14,6 @@ int sch56xx_read_virtual_reg16(u16 addr, u16 reg);
 int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
 			       int high_nibble);
 
-struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
-	u16 addr, u32 revision, struct mutex *io_lock, int check_enabled);
+void sch56xx_watchdog_register(struct device *parent, u16 addr, u32 revision,
+			       struct mutex *io_lock, int check_enabled);
 void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data);