[PATCH 1/8] platform/x86: isst_if_mmio: switch to devm_mutex_init()

[chitranshmandhaniya@gmail.com]

From: Chitransh Mandhaniya <Chitransh_Mandhaniya@dell.com>

Replace mutex_init() with devm_mutex_init() so the mutex lifecycle is
managed by devres.  This removes the need for manual mutex_destroy()
calls in both the error path and the remove callback.

Since the only action on cdev_register failure was mutex_destroy(),
simplify the tail of the probe function to return the registration
result directly.

Signed-off-by: Chitransh Mandhaniya <Chitransh_Mandhaniya@dell.com>
---
 .../platform/x86/intel/speed_select_if/isst_if_mmio.c | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/x86/intel/speed_select_if/isst_if_mmio.c b/drivers/platform/x86/intel/speed_select_if/isst_if_mmio.c
index 950ede5eab76..0a3fdf6b8bca 100644
--- a/drivers/platform/x86/intel/speed_select_if/isst_if_mmio.c
+++ b/drivers/platform/x86/intel/speed_select_if/isst_if_mmio.c
@@ -124,7 +124,9 @@ static int isst_if_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (IS_ERR(punit_dev->punit_mmio))
 		return PTR_ERR(punit_dev->punit_mmio);
 
-	mutex_init(&punit_dev->mutex);
+	ret = devm_mutex_init(&pdev->dev, &punit_dev->mutex);
+	if (ret)
+		return ret;
 	pci_set_drvdata(pdev, punit_dev);
 
 	memset(&cb, 0, sizeof(cb));
@@ -132,11 +134,7 @@ static int isst_if_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	cb.offset = offsetof(struct isst_if_io_regs, io_reg);
 	cb.cmd_callback = isst_if_mmio_rd_wr;
 	cb.owner = THIS_MODULE;
-	ret = isst_if_cdev_register(ISST_IF_DEV_MMIO, &cb);
-	if (ret)
-		mutex_destroy(&punit_dev->mutex);
-
-	return ret;
+	return isst_if_cdev_register(ISST_IF_DEV_MMIO, &cb);
 }
 
 static void isst_if_remove(struct pci_dev *pdev)
@@ -145,7 +143,6 @@ static void isst_if_remove(struct pci_dev *pdev)
 
 	punit_dev = pci_get_drvdata(pdev);
 	isst_if_cdev_unregister(ISST_IF_DEV_MMIO);
-	mutex_destroy(&punit_dev->mutex);
 }
 
 static int __maybe_unused isst_if_suspend(struct device *device)
-- 
2.43.0