[PATCH] slimbus: preserve ports after failed disconnect

[Avi Weiss <thnkslprpt@gmail.com>]

slim_stream_unprepare() ignores errors from slim_disconnect_port() and
frees the port array even when a disconnect transfer fails. The helper
also marks the port disconnected before issuing the transfer, losing
track of which ports still need disconnecting.

Update port state only after a successful transfer. Attempt every
disconnect, return the first error, and retain the port array on
failure so completed ports can be skipped on retry. Free any retained
port array in slim_stream_free().

Fixes: abb9c9b8b51b ("slimbus: stream: add stream support")
Signed-off-by: Avi Weiss <thnkslprpt@gmail.com>
---
 drivers/slimbus/stream.c | 23 +++++++++++++++++++----
 1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/drivers/slimbus/stream.c b/drivers/slimbus/stream.c
index b4e70a7edd1cc..ab26b243802df 100644
--- a/drivers/slimbus/stream.c
+++ b/drivers/slimbus/stream.c
@@ -150,12 +150,17 @@ static int slim_disconnect_port(struct slim_stream_runtime *stream,
 	struct slim_val_inf msg = {0, 1, NULL, wbuf, NULL};
 	u8 mc = SLIM_MSG_MC_DISCONNECT_PORT;
 	DEFINE_SLIM_LDEST_TXN(txn, mc, 5, stream->dev->laddr, &msg);
+	int ret;
 
 	wbuf[0] = port->id;
+	ret = slim_do_transfer(sdev->ctrl, &txn);
+	if (ret)
+		return ret;
+
 	port->ch.state = SLIM_CH_STATE_DISCONNECTED;
 	port->state = SLIM_PORT_DISCONNECTED;
 
-	return slim_do_transfer(sdev->ctrl, &txn);
+	return 0;
 }
 
 static int slim_deactivate_remove_channel(struct slim_stream_runtime *stream,
@@ -448,13 +453,22 @@ EXPORT_SYMBOL_GPL(slim_stream_disable);
  */
 int slim_stream_unprepare(struct slim_stream_runtime *stream)
 {
-	int i;
+	int ret = 0, err, i;
 
 	if (!stream->ports || !stream->num_ports)
 		return -EINVAL;
 
-	for (i = 0; i < stream->num_ports; i++)
-		slim_disconnect_port(stream, &stream->ports[i]);
+	for (i = 0; i < stream->num_ports; i++) {
+		if (stream->ports[i].state == SLIM_PORT_DISCONNECTED)
+			continue;
+
+		err = slim_disconnect_port(stream, &stream->ports[i]);
+		if (err && !ret)
+			ret = err;
+	}
+
+	if (ret)
+		return ret;
 
 	kfree(stream->ports);
 	stream->ports = NULL;
@@ -484,6 +498,7 @@ int slim_stream_free(struct slim_stream_runtime *stream)
 	list_del(&stream->node);
 	spin_unlock(&sdev->stream_list_lock);
 
+	kfree(stream->ports);
 	kfree(stream->name);
 	kfree(stream);
 

base-commit: 65ba8f34ec886ec72b2c07ddc8cf3d815c32869d
-- 
2.43.0