[PATCH] can: mcp251x: add error handling for power enable in open and resume

[Wenyuan Li]

Add missing error handling for mcp251x_power_enable() calls in both
mcp251x_open() and mcp251x_can_resume() functions.

In mcp251x_open(), if power enable fails, the driver should not continue
with device initialization. Add proper error checking and jump to
existing out_close label.

In mcp251x_can_resume(), if power enable fails during system resume,
propagate the error to PM framework and log the error with dev_err()
for debugging.

This ensures the driver properly handles power control failures and
maintains correct device state.
Signed-off-by: Wenyuan Li <2063309626@xxxxxx>
---
 drivers/net/can/spi/mcp251x.c | 28 +++++++++++++++++++++++-----
 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c
index bb7782582f40..807293a7857f 100644
--- a/drivers/net/can/spi/mcp251x.c
+++ b/drivers/net/can/spi/mcp251x.c
@@ -1225,7 +1225,11 @@ static int mcp251x_open(struct net_device *net)
 	}
 
 	mutex_lock(&priv->mcp_lock);
-	mcp251x_power_enable(priv->transceiver, 1);
+	ret = mcp251x_power_enable(priv->transceiver, 1);
+	if (ret) {
+		dev_err(&spi->dev, "failed to enable power: %d\n", ret);
+		goto out_close_candev;
+	}
 
 	priv->force_quit = 0;
 	priv->tx_skb = NULL;
@@ -1272,6 +1276,7 @@ static int mcp251x_open(struct net_device *net)
 	mcp251x_hw_sleep(spi);
 out_close:
 	mcp251x_power_enable(priv->transceiver, 0);
+out_close_candev:
 	close_candev(net);
 	mutex_unlock(&priv->mcp_lock);
 	if (release_irq)
@@ -1516,11 +1521,23 @@ static int __maybe_unused mcp251x_can_resume(struct device *dev)
 {
 	struct spi_device *spi = to_spi_device(dev);
 	struct mcp251x_priv *priv = spi_get_drvdata(spi);
+	int ret = 0;
 
-	if (priv->after_suspend & AFTER_SUSPEND_POWER)
-		mcp251x_power_enable(priv->power, 1);
-	if (priv->after_suspend & AFTER_SUSPEND_UP)
-		mcp251x_power_enable(priv->transceiver, 1);
+	if (priv->after_suspend & AFTER_SUSPEND_POWER) {
+		ret = mcp251x_power_enable(priv->power, 1);
+		if (ret) {
+			dev_err(dev, "Failed to restore power: %d\n", ret);
+			goto out;
+		}
+	}
+
+	if (priv->after_suspend & AFTER_SUSPEND_UP) {
+		ret = mcp251x_power_enable(priv->power, 1);
+		if (ret) {
+			dev_err(dev, "Failed to restore power: %d\n", ret);
+			goto out;
+		}
+	}
 
 	if (priv->after_suspend & (AFTER_SUSPEND_POWER | AFTER_SUSPEND_UP))
 		queue_work(priv->wq, &priv->restart_work);
@@ -1529,6 +1546,7 @@ static int __maybe_unused mcp251x_can_resume(struct device *dev)
 
 	priv->force_quit = 0;
 	enable_irq(spi->irq);
+out:
 	return 0;
 }
 
-- 
2.43.0