[PATCH v3 18/22] drm/bridge: imx8qxp-pixel-link: simplify logic to find next bridge
From: Luca Ceresoli <luca.ceresoli@bootlin.com>
Date: 2025-12-16 18:00:54
Also in:
dri-devel, imx, linux-amlogic, linux-doc, lkml
Subsystem:
drm drivers, drm drivers and misc gpu patches, drm drivers for bridge chips, drm drivers for freescale imx bridge, the rest · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Andrzej Hajda, Neil Armstrong, Robert Foss, Liu Ying, Linus Torvalds
imx8qxp_pixel_link_find_next_bridge() uses a sophisticated logic to find the preferred next bridge, using an array with two supporting index variables. This is more sophisticated than required because we only ever need a pointer to the "current" bridge and to the "best so far" bridge. Additionally this logic is going to make the addition of proper refcounting quite complex. Rewrite the logic using two drm_bridge pointers, which is by itself slightly simpler and is a preparation step for introducing bridge refcounting in a later commit. Also reword a comment to make it clearer. Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com> --- drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c | 23 +++++++++++------------ 1 file changed, 11 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
index e5943506981d..53016f0d53a0 100644
--- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
+++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c@@ -261,12 +261,10 @@ imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl) { struct device_node *np = pl->dev->of_node; struct device_node *port, *remote; - struct drm_bridge *next_bridge[PL_MAX_NEXT_BRIDGES]; + struct drm_bridge *selected_bridge = NULL; u32 port_id; bool found_port = false; - int reg, ep_cnt = 0; - /* select the first next bridge by default */ - int bridge_sel = 0; + int reg; for (port_id = 1; port_id <= PL_MAX_MST_ADDR + 1; port_id++) { port = of_graph_get_port_by_id(np, port_id);
@@ -300,24 +298,25 @@ imx8qxp_pixel_link_find_next_bridge(struct imx8qxp_pixel_link *pl) continue; } - next_bridge[ep_cnt] = of_drm_find_bridge(remote); - if (!next_bridge[ep_cnt]) { + struct drm_bridge *next_bridge = of_drm_find_bridge(remote); + if (!next_bridge) { of_node_put(remote); return ERR_PTR(-EPROBE_DEFER); } - /* specially select the next bridge with companion PXL2DPI */ - if (of_property_present(remote, "fsl,companion-pxl2dpi")) - bridge_sel = ep_cnt; - - ep_cnt++; + /* + * Select the next bridge with companion PXL2DPI if + * present, otherwise default to the first bridge + */ + if (!selected_bridge || of_property_present(remote, "fsl,companion-pxl2dpi")) + selected_bridge = next_bridge; of_node_put(remote); } pl->mst_addr = port_id - 1; - return next_bridge[bridge_sel]; + return selected_bridge; } static int imx8qxp_pixel_link_bridge_probe(struct platform_device *pdev)
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2.52.0