From bafc628678796e3a05bd54c30280f4ecdaf3ebba Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Tue, 27 May 2025 16:21:47 +0200 Subject: [PATCH] drm/bridge: samsung-dsim: use while loop in samsung_dsim_transfer_start 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. Reviewed-by: Alexander Stein Reviewed-by: Frieder Schrempf Link: https://lore.kernel.org/r/20250527-samsung-dsim-v1-1-5be520d84fbb@pengutronix.de Signed-off-by: Philipp Zabel --- 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 f2f666b27d2d..2acf5d86174b 100644 --- a/drivers/gpu/drm/bridge/samsung-dsim.c +++ b/drivers/gpu/drm/bridge/samsung-dsim.c @@ -1236,43 +1236,34 @@ 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)