[PATCH v2 0/2] mailbox: cix: clean up channel validation and error reporting

[PATCH v2 0/2] mailbox: cix: clean up channel validation and error reporting

[kr494167]

From: Surendra Singh Chouhan <kr494167@gmail.com>

Per maintainer review feedback from Jassi Brar, this patch series splits
the CIX mailbox driver fixes into two separate patches:

Patch 1 validates fast channel index bounds before request_irq() in
cix_mbox_startup() to avoid unnecessary IRQ registration and teardown churn.

Patch 2 fixes the DT property name string typo ("cix,mbox_dir" -> "cix,mbox-dir")
and converts cix_mbox_probe() error paths to dev_err_probe().

v2:
 - Split into 2 separate patches per Jassi Brar review.
 - Drop bounced address peter.chen@cixtech.com.

Surendra Singh Chouhan (2):
  mailbox: cix: validate fast channel index before request_irq()
  mailbox: cix: fix DT property name string typo and use dev_err_probe()

 drivers/mailbox/cix-mailbox.c | 36 +++++++++++++++--------------------
 1 file changed, 15 insertions(+), 21 deletions(-)

-- 
2.55.0

[PATCH v2 1/2] mailbox: cix: validate fast channel index before request_irq()

[kr494167]

From: Surendra Singh Chouhan <kr494167@gmail.com>

cix_mbox_startup() checked fast channel index constraints (index < 0 ||
index > CIX_MBOX_FAST_IDX) inside the channel switch block after
calling request_irq(). If validation failed, it triggered a free_irq()
cleanup path.

Validating channel parameters prior to request_irq() avoids unnecessary
IRQ registration and teardown churn.

Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>
---
 drivers/mailbox/cix-mailbox.c | 20 +++++++++-----------
 1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/mailbox/cix-mailbox.c b/drivers/mailbox/cix-mailbox.c
index 43c76cdab24a..615218c69eeb 100644
--- a/drivers/mailbox/cix-mailbox.c
+++ b/drivers/mailbox/cix-mailbox.c
@@ -403,6 +403,13 @@ static int cix_mbox_startup(struct mbox_chan *chan)
 	int index = cp->index, ret;
 	u32 val;
 
+	if (cp->type == CIX_MBOX_TYPE_FAST && priv->dir == CIX_MBOX_RX) {
+		if (index < 0 || index > CIX_MBOX_FAST_IDX) {
+			dev_err(priv->dev, "Invalid index %d\n", index);
+			return -EINVAL;
+		}
+	}
+
 	ret = request_irq(priv->irq, cix_mbox_isr, IRQF_NO_SUSPEND,
 			  dev_name(priv->dev), chan);
 	if (ret) {
@@ -448,11 +455,6 @@ static int cix_mbox_startup(struct mbox_chan *chan)
 	case CIX_MBOX_TYPE_FAST:
 		/* Only RX channel has intterupt */
 		if (priv->dir == CIX_MBOX_RX) {
-			if (index < 0 || index > CIX_MBOX_FAST_IDX) {
-				dev_err(priv->dev, "Invalid index %d\n", index);
-				ret = -EINVAL;
-				goto failed;
-			}
 			/* enable fast channel interrupt */
 			val = cix_mbox_read(priv, CIX_INT_ENABLE_SIDE_B);
 			val |= CIX_FAST_CH_INT(index);
@@ -461,14 +463,10 @@ static int cix_mbox_startup(struct mbox_chan *chan)
 		break;
 	default:
 		dev_err(priv->dev, "Invalid channel type: %d\n", cp->type);
-		ret = -EINVAL;
-		goto failed;
+		free_irq(priv->irq, chan);
+		return -EINVAL;
 	}
 	return 0;
-
-failed:
-	free_irq(priv->irq, chan);
-	return ret;
 }
 
 static void cix_mbox_shutdown(struct mbox_chan *chan)
-- 
2.55.0

[PATCH v2 2/2] mailbox: cix: fix DT property name string typo and use dev_err_probe()

[kr494167]

From: Surendra Singh Chouhan <kr494167@gmail.com>

cix_mbox_probe() logged property error messages referencing
"cix,mbox_dir" (with an underscore) instead of the actual DT property
string "cix,mbox-dir".

Fix the DT property string in error log messages and convert probe error
paths to dev_err_probe().

Signed-off-by: Surendra Singh Chouhan <kr494167@gmail.com>
---
 drivers/mailbox/cix-mailbox.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/mailbox/cix-mailbox.c b/drivers/mailbox/cix-mailbox.c
index 615218c69eeb..fb5d7641ba90 100644
--- a/drivers/mailbox/cix-mailbox.c
+++ b/drivers/mailbox/cix-mailbox.c
@@ -585,19 +585,15 @@ static int cix_mbox_probe(struct platform_device *pdev)
 	if (priv->irq < 0)
 		return priv->irq;
 
-	if (device_property_read_string(dev, "cix,mbox-dir", &dir_str)) {
-		dev_err(priv->dev, "cix,mbox_dir property not found\n");
-		return -EINVAL;
-	}
+	if (device_property_read_string(dev, "cix,mbox-dir", &dir_str))
+		return dev_err_probe(dev, -EINVAL, "cix,mbox-dir property not found\n");
 
 	if (!strcmp(dir_str, "tx"))
 		priv->dir = 0;
 	else if (!strcmp(dir_str, "rx"))
 		priv->dir = 1;
-	else {
-		dev_err(priv->dev, "cix,mbox_dir=%s is not expected\n", dir_str);
-		return -EINVAL;
-	}
+	else
+		return dev_err_probe(dev, -EINVAL, "cix,mbox-dir=%s is not expected\n", dir_str);
 
 	cix_mbox_init(priv);
 
@@ -611,9 +607,9 @@ static int cix_mbox_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, priv);
 	ret = devm_mbox_controller_register(dev, &priv->mbox);
 	if (ret)
-		dev_err(dev, "Failed to register mailbox %d\n", ret);
+		return dev_err_probe(dev, ret, "Failed to register mailbox\n");
 
-	return ret;
+	return 0;
 }
 
 static const struct of_device_id cix_mbox_dt_ids[] = {
-- 
2.55.0