From 65112cfa56c32030a7f04a8a4c28251b89b5cf26 Mon Sep 17 00:00:00 2001 From: Fabrizio Castro Date: Tue, 17 Dec 2019 13:45:58 +0000 Subject: [PATCH] drm: rcar-du: lvds: Get dual link configuration from DT For dual-LVDS configurations, it is now possible to mark the DT port nodes for the sink with boolean properties (like dual-lvds-even-pixels and dual-lvds-odd-pixels) to let drivers know the encoders need to be configured in dual-LVDS mode. Rework the implementation of rcar_lvds_parse_dt_companion to make use of the DT markers while keeping backward compatibility. Signed-off-by: Fabrizio Castro Reviewed-by: Laurent Pinchart Signed-off-by: Laurent Pinchart --- drivers/gpu/drm/rcar-du/rcar_lvds.c | 54 +++++++++++++++++++++++++++++++------ 1 file changed, 46 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c index ec63546ade7e..1749b9c48d5d 100644 --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c @@ -678,7 +678,10 @@ static int rcar_lvds_parse_dt_companion(struct rcar_lvds *lvds) { const struct of_device_id *match; struct device_node *companion; + struct device_node *port0, *port1; + struct rcar_lvds *companion_lvds; struct device *dev = lvds->dev; + int dual_link; int ret = 0; /* Locate the companion LVDS encoder for dual-link operation, if any. */ @@ -697,13 +700,54 @@ static int rcar_lvds_parse_dt_companion(struct rcar_lvds *lvds) goto done; } + /* + * We need to work out if the sink is expecting us to function in + * dual-link mode. We do this by looking at the DT port nodes we are + * connected to, if they are marked as expecting even pixels and + * odd pixels than we need to enable vertical stripe output. + */ + port0 = of_graph_get_port_by_id(dev->of_node, 1); + port1 = of_graph_get_port_by_id(companion, 1); + dual_link = drm_of_lvds_get_dual_link_pixel_order(port0, port1); + of_node_put(port0); + of_node_put(port1); + + if (dual_link >= DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS) + lvds->dual_link = true; + else if (lvds->next_bridge && lvds->next_bridge->timings) + /* + * Early dual-link bridge specific implementations populate the + * timings field of drm_bridge, read the dual_link flag off the + * bridge directly for backward compatibility. + */ + lvds->dual_link = lvds->next_bridge->timings->dual_link; + + if (!lvds->dual_link) { + dev_dbg(dev, "Single-link configuration detected\n"); + goto done; + } + lvds->companion = of_drm_find_bridge(companion); if (!lvds->companion) { ret = -EPROBE_DEFER; goto done; } - dev_dbg(dev, "Found companion encoder %pOF\n", companion); + dev_dbg(dev, + "Dual-link configuration detected (companion encoder %pOF)\n", + companion); + + /* + * FIXME: We should not be messing with the companion encoder private + * data from the primary encoder, we should rather let the companion + * encoder work things out on its own. However, the companion encoder + * doesn't hold a reference to the primary encoder, and + * drm_of_lvds_get_dual_link_pixel_order needs to be given references + * to the output ports of both encoders, therefore leave it like this + * for the time being. + */ + companion_lvds = bridge_to_rcar_lvds(lvds->companion); + companion_lvds->dual_link = true; done: of_node_put(companion); @@ -720,13 +764,7 @@ static int rcar_lvds_parse_dt(struct rcar_lvds *lvds) if (ret) goto done; - if ((lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK) && - lvds->next_bridge) - lvds->dual_link = lvds->next_bridge->timings - ? lvds->next_bridge->timings->dual_link - : false; - - if (lvds->dual_link) + if (lvds->info->quirks & RCAR_LVDS_QUIRK_DUAL_LINK) ret = rcar_lvds_parse_dt_companion(lvds); done: -- 2.11.0