--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2025 Bootlin
+ * Author: Kory Maincent <kory.maincent@bootlin.com>
+ *
+ * To support the legacy "ti,tilcdc,panel" binding, the devicetree has to
+ * be transformed to the new panel-dpi binding with the endpoint associated.
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/slab.h>
+
+/* Embedded dtbo symbols created by cmd_wrap_S_dtb in scripts/Makefile.lib */
+extern char __dtbo_tilcdc_panel_legacy_begin[];
+extern char __dtbo_tilcdc_panel_legacy_end[];
+
+static int __init
+tilcdc_panel_update_prop(struct of_changeset *ocs, struct device_node *node,
+ char *name, void *val, int length)
+{
+ struct property *prop;
+
+ prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+ if (!prop)
+ return -ENOMEM;
+
+ prop->name = kstrdup(name, GFP_KERNEL);
+ prop->length = length;
+ prop->value = kmemdup(val, length, GFP_KERNEL);
+ if (!prop->name || !prop->value) {
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+ return -ENOMEM;
+ }
+
+ return of_changeset_update_property(ocs, node, prop);
+}
+
+static int __init tilcdc_panel_copy_props(struct device_node *old_panel,
+ struct device_node *new_panel)
+{
+ struct device_node *old_timing __free(device_node) = NULL;
+ struct device_node *new_timing __free(device_node) = NULL;
+ struct device_node *panel_info __free(device_node) = NULL;
+ struct device_node *child __free(device_node) = NULL;
+ u32 invert_pxl_clk = 0, sync_edge = 0;
+ struct of_changeset ocs;
+ struct property *prop;
+ int ret;
+
+ child = of_get_child_by_name(old_panel, "display-timings");
+ if (!child)
+ return -EINVAL;
+
+ /* The default display timing is the one specified as native-mode.
+ * If no native-mode is specified then the first node is assumed
+ * to be the native mode.
+ */
+ old_timing = of_parse_phandle(child, "native-mode", 0);
+ if (!old_timing) {
+ old_timing = of_get_next_child(child, NULL);
+ if (!old_timing)
+ return -EINVAL;
+ }
+
+ panel_info = of_get_child_by_name(old_panel, "panel-info");
+ if (!panel_info)
+ return -EINVAL;
+
+ of_changeset_init(&ocs);
+
+ /* Copy all panel properties to the new panel node */
+ for_each_property_of_node(old_panel, prop) {
+ if (!strncmp(prop->name, "compatible", sizeof("compatible")))
+ continue;
+
+ ret = tilcdc_panel_update_prop(&ocs, new_panel, prop->name,
+ prop->value, prop->length);
+ if (ret)
+ goto destroy_ocs;
+ }
+
+ new_timing = of_changeset_create_node(&ocs, new_panel, "panel-timing");
+ if (!new_timing) {
+ ret = -ENODEV;
+ goto destroy_ocs;
+ }
+
+ /* Copy all panel timing properties to the new panel node */
+ for_each_property_of_node(old_timing, prop) {
+ ret = tilcdc_panel_update_prop(&ocs, new_timing, prop->name,
+ prop->value, prop->length);
+ if (ret)
+ goto destroy_ocs;
+ }
+
+ /* Looked only for these two parameter as all the other are always
+ * set to default and not related to common DRM properties.
+ */
+ of_property_read_u32(panel_info, "invert-pxl-clk", &invert_pxl_clk);
+ of_property_read_u32(panel_info, "sync-edge", &sync_edge);
+
+ if (!invert_pxl_clk) {
+ ret = tilcdc_panel_update_prop(&ocs, new_timing, "pixelclk-active",
+ &(u32){cpu_to_be32(1)}, sizeof(u32));
+ if (ret)
+ goto destroy_ocs;
+ }
+
+ if (!sync_edge) {
+ ret = tilcdc_panel_update_prop(&ocs, new_timing, "syncclk-active",
+ &(u32){cpu_to_be32(1)}, sizeof(u32));
+ if (ret)
+ goto destroy_ocs;
+ }
+
+ /* Remove compatible property to avoid any driver compatible match */
+ of_changeset_remove_property(&ocs, old_panel,
+ of_find_property(old_panel, "compatible", NULL));
+
+ of_changeset_apply(&ocs);
+ return 0;
+
+destroy_ocs:
+ of_changeset_destroy(&ocs);
+ return ret;
+}
+
+static const struct of_device_id tilcdc_panel_of_match[] __initconst = {
+ { .compatible = "ti,tilcdc,panel", },
+ {},
+};
+
+static const struct of_device_id tilcdc_of_match[] __initconst = {
+ { .compatible = "ti,am33xx-tilcdc", },
+ { .compatible = "ti,da850-tilcdc", },
+ {},
+};
+
+static int __init tilcdc_panel_legacy_init(void)
+{
+ struct device_node *new_panel __free(device_node) = NULL;
+ struct device_node *panel __free(device_node) = NULL;
+ struct device_node *lcdc __free(device_node) = NULL;
+ void *dtbo_start;
+ u32 dtbo_size;
+ int ovcs_id;
+ int ret;
+
+ lcdc = of_find_matching_node(NULL, tilcdc_of_match);
+ panel = of_find_matching_node(NULL, tilcdc_panel_of_match);
+
+ if (!of_device_is_available(panel) ||
+ !of_device_is_available(lcdc))
+ return 0;
+
+ dtbo_start = __dtbo_tilcdc_panel_legacy_begin;
+ dtbo_size = __dtbo_tilcdc_panel_legacy_end -
+ __dtbo_tilcdc_panel_legacy_begin;
+
+ ret = of_overlay_fdt_apply(dtbo_start, dtbo_size, &ovcs_id, NULL);
+ if (ret)
+ return ret;
+
+ new_panel = of_find_node_by_name(NULL, "tilcdc-panel-dpi");
+ if (!new_panel) {
+ ret = -ENODEV;
+ goto overlay_remove;
+ }
+
+ ret = tilcdc_panel_copy_props(panel, new_panel);
+ if (ret)
+ goto overlay_remove;
+
+ return 0;
+
+overlay_remove:
+ of_overlay_remove(&ovcs_id);
+ return ret;
+}
+
+subsys_initcall(tilcdc_panel_legacy_init);
projects / thirdparty / kernel / linux.git / commitdiff
