[PATCH 1/2] drm/bridge: samsung-dsim: use while loop in samsung_dsim_transfer_start

[Philipp Zabel]

Turn the open-coded goto-again construct into a while loop, to make
samsung_dsim_transfer_start() a bit shorter and easier to read.

Hold the spinlock when looping back around and avoid the duplicated
list_empty() check.

Signed-off-by: Philipp Zabel <p.zabel at pengutronix.de>
---
 drivers/gpu/drm/bridge/samsung-dsim.c | 51 +++++++++++++++--------------------
 1 file changed, 21 insertions(+), 30 deletions(-)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 0014c497e3fe7d8349a119dbdda30d65d816cccf..1dfc9710bee5134e0e0114ce52f673c21564b11b 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -1235,43 +1235,34 @@ static void samsung_dsim_transfer_start(struct samsung_dsim *dsi)
 {
 	unsigned long flags;
 	struct samsung_dsim_transfer *xfer;
-	bool start = false;
 
-again:
 	spin_lock_irqsave(&dsi->transfer_lock, flags);
 
-	if (list_empty(&dsi->transfer_list)) {
+	while (!list_empty(&dsi->transfer_list)) {
+		xfer = list_first_entry(&dsi->transfer_list,
+					struct samsung_dsim_transfer, list);
+
 		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
-		return;
+
+		if (xfer->packet.payload_length &&
+		    xfer->tx_done == xfer->packet.payload_length)
+			/* waiting for RX */
+			return;
+
+		samsung_dsim_send_to_fifo(dsi, xfer);
+
+		if (xfer->packet.payload_length || xfer->rx_len)
+			return;
+
+		xfer->result = 0;
+		complete(&xfer->completed);
+
+		spin_lock_irqsave(&dsi->transfer_lock, flags);
+
+		list_del_init(&xfer->list);
 	}
 
-	xfer = list_first_entry(&dsi->transfer_list,
-				struct samsung_dsim_transfer, list);
-
 	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
-
-	if (xfer->packet.payload_length &&
-	    xfer->tx_done == xfer->packet.payload_length)
-		/* waiting for RX */
-		return;
-
-	samsung_dsim_send_to_fifo(dsi, xfer);
-
-	if (xfer->packet.payload_length || xfer->rx_len)
-		return;
-
-	xfer->result = 0;
-	complete(&xfer->completed);
-
-	spin_lock_irqsave(&dsi->transfer_lock, flags);
-
-	list_del_init(&xfer->list);
-	start = !list_empty(&dsi->transfer_list);
-
-	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
-
-	if (start)
-		goto again;
 }
 
 static bool samsung_dsim_transfer_finish(struct samsung_dsim *dsi)

-- 
2.39.5