[PATCH 06/12] crypto: atmel-sha204a - add i2c hw client list and improve probe error handling

[Lothar Rubusch]

Add registration of the SHA204A I2C client into the shared atmel_i2c client
management list during probe.

This allows the driver to participate in the common hardware selection
infrastructure used by Atmel crypto devices.

Improve error handling in atmel_sha204a_probe() by ensuring that partial
initialization (hwrng registration or sysfs creation) results in proper
cleanup of the client list entry.

No functional change intended beyond improved lifecycle handling.

Signed-off-by: Lothar Rubusch <l.rubusch at gmail.com>
---
 drivers/crypto/atmel-sha204a.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/atmel-sha204a.c b/drivers/crypto/atmel-sha204a.c
index 6e6ac4770416..cdfdcf2e43a7 100644
--- a/drivers/crypto/atmel-sha204a.c
+++ b/drivers/crypto/atmel-sha204a.c
@@ -173,6 +173,13 @@ static int atmel_sha204a_probe(struct i2c_client *client)
 
 	i2c_priv = i2c_get_clientdata(client);
 
+	/* add to client list */
+	spin_lock(&atmel_i2c_mgmt.i2c_list_lock);
+	list_add_tail(&i2c_priv->i2c_client_list_node,
+		      &atmel_i2c_mgmt.i2c_client_list);
+	spin_unlock(&atmel_i2c_mgmt.i2c_list_lock);
+
+	/* register rng */
 	memset(&i2c_priv->hwrng, 0, sizeof(i2c_priv->hwrng));
 
 	i2c_priv->hwrng.name = dev_name(&client->dev);
@@ -183,15 +190,24 @@ static int atmel_sha204a_probe(struct i2c_client *client)
 		i2c_priv->hwrng.quality = *quality;
 
 	ret = devm_hwrng_register(&client->dev, &i2c_priv->hwrng);
-	if (ret)
+	if (ret) {
 		dev_warn(&client->dev, "failed to register RNG (%d)\n", ret);
+		goto err_list_del;
+	}
 
 	ret = sysfs_create_group(&client->dev.kobj, &atmel_sha204a_groups);
 	if (ret) {
 		dev_err(&client->dev, "failed to register sysfs entry\n");
-		return ret;
+		goto err_list_del;
 	}
 
+	return ret;
+
+err_list_del:
+	spin_lock(&atmel_i2c_mgmt.i2c_list_lock);
+	list_del(&i2c_priv->i2c_client_list_node);
+	spin_unlock(&atmel_i2c_mgmt.i2c_list_lock);
+
 	return ret;
 }
 
-- 
2.53.0