[PATCH] platform/x86: lenovo: convert mutex_init() users to devm_mutex_init()

[surirajat@gmail.com]

From: Rajat Suri <rajat.suri@dell.com>

Convert the mutex_init() calls under drivers/platform/x86/lenovo/
to devm_mutex_init() so that the mutex lifecycle is managed by devres.

This removes the need for manual mutex_destroy() calls in wmi-camera and
ideapad-laptop, and fixes thinkpad_acpi, which never destroyed the
hotkey, brightness, volume and fan mutexes on its teardown path.

Details per driver:

 - wmi-camera: bind notify_lock to the WMI device and drop the
   mutex_destroy() from remove().

 - ideapad-laptop: allocate the DYTC private data with devm_kzalloc() and
   bind its mutex to the platform device. Calling mutex_destroy() on a
   manually freed object is not possible with devres, so the kfree() and
   ideapad_dytc_profile_exit() helper are removed as well. The memory now
   outlives the platform profile registration, which is also devm managed
   and therefore released in reverse order.

 - thinkpad_acpi: bind the hotkey, hotkey thread data, brightness, volume
   and fan mutexes to tpacpi_pdev, which is registered before any
   subdriver init runs, and propagate a possible failure from
   devm_mutex_init().

No functional change intended.

Signed-off-by: Rajat Suri <rajat.suri@dell.com>
---
 drivers/platform/x86/lenovo/ideapad-laptop.c | 23 ++++----------------
 drivers/platform/x86/lenovo/thinkpad_acpi.c  | 21 +++++++++++++-----
 drivers/platform/x86/lenovo/wmi-camera.c     |  6 +----
 3 files changed, 21 insertions(+), 29 deletions(-)

diff --git a/drivers/platform/x86/lenovo/ideapad-laptop.c b/drivers/platform/x86/lenovo/ideapad-laptop.c
index fcb5ed7035f5..ee8e00bdaf6b 100644
--- a/drivers/platform/x86/lenovo/ideapad-laptop.c
+++ b/drivers/platform/x86/lenovo/ideapad-laptop.c
@@ -1172,11 +1172,13 @@ static int ideapad_dytc_profile_init(struct ideapad_private *priv)
 		return -ENODEV;
 	}
 
-	priv->dytc = kzalloc_obj(*priv->dytc);
+	priv->dytc = devm_kzalloc(&priv->platform_device->dev, sizeof(*priv->dytc), GFP_KERNEL);
 	if (!priv->dytc)
 		return -ENOMEM;
 
-	mutex_init(&priv->dytc->mutex);
+	err = devm_mutex_init(&priv->platform_device->dev, &priv->dytc->mutex);
+	if (err)
+		goto pp_reg_failed;
 
 	priv->dytc->priv = priv;
 
@@ -1195,24 +1197,11 @@ static int ideapad_dytc_profile_init(struct ideapad_private *priv)
 	return 0;
 
 pp_reg_failed:
-	mutex_destroy(&priv->dytc->mutex);
-	kfree(priv->dytc);
 	priv->dytc = NULL;
 
 	return err;
 }
 
-static void ideapad_dytc_profile_exit(struct ideapad_private *priv)
-{
-	if (!priv->dytc)
-		return;
-
-	mutex_destroy(&priv->dytc->mutex);
-	kfree(priv->dytc);
-
-	priv->dytc = NULL;
-}
-
 /*
  * Rfkill
  */
@@ -2487,8 +2476,6 @@ static int ideapad_acpi_add(struct platform_device *pdev)
 	ideapad_backlight_exit(priv);
 
 backlight_failed:
-	ideapad_dytc_profile_exit(priv);
-
 	for (i = 0; i < IDEAPAD_RFKILL_DEV_NUM; i++)
 		ideapad_unregister_rfkill(priv, i);
 
@@ -2516,8 +2503,6 @@ static void ideapad_acpi_remove(struct platform_device *pdev)
 				   ideapad_acpi_notify);
 
 	ideapad_backlight_exit(priv);
-	ideapad_dytc_profile_exit(priv);
-
 	for (i = 0; i < IDEAPAD_RFKILL_DEV_NUM; i++)
 		ideapad_unregister_rfkill(priv, i);
 
diff --git a/drivers/platform/x86/lenovo/thinkpad_acpi.c b/drivers/platform/x86/lenovo/thinkpad_acpi.c
index 4f81855ad721..8c7d6f281ae3 100644
--- a/drivers/platform/x86/lenovo/thinkpad_acpi.c
+++ b/drivers/platform/x86/lenovo/thinkpad_acpi.c
@@ -3381,10 +3381,14 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
 	       tpacpi_inputdev->close != NULL);
 
 	TPACPI_ACPIHANDLE_INIT(hkey);
-	mutex_init(&hotkey_mutex);
+	res = devm_mutex_init(&tpacpi_pdev->dev, &hotkey_mutex);
+	if (res)
+		return res;
 
 #ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
-	mutex_init(&hotkey_thread_data_mutex);
+	res = devm_mutex_init(&tpacpi_pdev->dev, &hotkey_thread_data_mutex);
+	if (res)
+		return res;
 #endif
 
 	/* hotkey not supported on 570 */
@@ -6834,7 +6838,9 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
 
 	vdbg_printk(TPACPI_DBG_INIT, "initializing brightness subdriver\n");
 
-	mutex_init(&brightness_mutex);
+	b = devm_mutex_init(&tpacpi_pdev->dev, &brightness_mutex);
+	if (b)
+		return b;
 
 	quirks = tpacpi_check_quirks(brightness_quirk_table,
 				ARRAY_SIZE(brightness_quirk_table));
@@ -7575,7 +7581,9 @@ static int __init volume_init(struct ibm_init_struct *iibm)
 
 	vdbg_printk(TPACPI_DBG_INIT, "initializing volume subdriver\n");
 
-	mutex_init(&volume_mutex);
+	rc = devm_mutex_init(&tpacpi_pdev->dev, &volume_mutex);
+	if (rc)
+		return rc;
 
 	/*
 	 * Check for module parameter bogosity, note that we
@@ -8913,11 +8921,14 @@ static const struct tpacpi_quirk fan_quirk_table[] __initconst = {
 static int __init fan_init(struct ibm_init_struct *iibm)
 {
 	unsigned long quirks;
+	int rc;
 
 	vdbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_FAN,
 			"initializing fan subdriver\n");
 
-	mutex_init(&fan_mutex);
+	rc = devm_mutex_init(&tpacpi_pdev->dev, &fan_mutex);
+	if (rc)
+		return rc;
 	fan_status_access_mode = TPACPI_FAN_NONE;
 	fan_control_access_mode = TPACPI_FAN_WR_NONE;
 	fan_control_commands = 0;
diff --git a/drivers/platform/x86/lenovo/wmi-camera.c b/drivers/platform/x86/lenovo/wmi-camera.c
index 89ecbce60bf4..de4596686d2a 100644
--- a/drivers/platform/x86/lenovo/wmi-camera.c
+++ b/drivers/platform/x86/lenovo/wmi-camera.c
@@ -107,9 +107,7 @@ static int lenovo_wmi_probe(struct wmi_device *wdev, const void *context)
 
 	dev_set_drvdata(&wdev->dev, priv);
 
-	mutex_init(&priv->notify_lock);
-
-	return 0;
+	return devm_mutex_init(&wdev->dev, &priv->notify_lock);
 }
 
 static void lenovo_wmi_remove(struct wmi_device *wdev)
@@ -118,8 +116,6 @@ static void lenovo_wmi_remove(struct wmi_device *wdev)
 
 	if (priv->idev)
 		input_unregister_device(priv->idev);
-
-	mutex_destroy(&priv->notify_lock);
 }
 
 static const struct wmi_device_id lenovo_wmi_id_table[] = {
-- 
2.43.0