To maintain backward compatibility while removing the deprecated
tilcdc_panel driver, add a tilcdc_panel_legacy subdriver that converts
the legacy "ti,tilcdc,panel" devicetree binding to the standard
panel-dpi binding at early boot.
The conversion uses an embedded device tree overlay that is applied and
modified during subsys_initcall. The process:
- Apply embedded overlay to create a tilcdc-panel-dpi node with
port/endpoint connections to the LCDC
- Copy all properties from the legacy panel node to the new
tilcdc-panel-dpi node
- Copy display-timings from the legacy panel
- Convert legacy panel-info properties (invert-pxl-clk, sync-edge) to
standard display timing properties (pixelclk-active, syncclk-active)
- Disable the legacy panel by removing its compatible property to
prevent the deprecated driver from binding
The result is a standard tilcdc-panel-dpi node with proper endpoints and
timing properties, allowing the DRM panel infrastructure to work with
legacy devicetrees without modification.
Other legacy panel-info properties are not migrated as they consistently
use default values across all mainline devicetrees and can be hardcoded
in the tilcdc driver.
This feature is optional via CONFIG_DRM_TILCDC_PANEL_LEGACY and should
only be enabled for systems with legacy devicetrees containing
"ti,tilcdc,panel" nodes.
Suggested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Link: https://lore.kernel.org/all/1d9a9269-bfda-4d43-938b-2df6b82b9369@ideasonboard.com/
Signed-off-by: Kory Maincent (TI.com) <kory.maincent@bootlin.com>
---
Using the approach of applying an overlay and then modifying the live
device tree is the solution I found that requires no modification of the
OF core. Dealing entirely with changesets would bring additional
requirements such as phandle resolution management, which is internal to
the OF framework. I intend to avoid OF core change to support this legacy
binding.
Change in v3:
- Use __free() macro instead of manual house cleaning.
- Enable CONFIG_DRM_TILCDC_PANEL_LEGACY config by default.
- Improve config description.
- Rename "panel-dpi" to "tilcdc-panel-dpi" to avoid any future conflict.
- Use OF changeset instead of modifying the live devicetree step by
step.
- Add kfree to avoid memory leak.
Change in v2:
- New patch.
---
drivers/gpu/drm/tilcdc/Kconfig | 16 ++
drivers/gpu/drm/tilcdc/Makefile | 2 +
drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c | 185 ++++++++++++++++++++++++
drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso | 29 ++++
4 files changed, 232 insertions(+)
diff --git a/drivers/gpu/drm/tilcdc/Kconfig b/drivers/gpu/drm/tilcdc/Kconfig
index 24f9a245ba593..4fca8058eb7db 100644
--- a/drivers/gpu/drm/tilcdc/Kconfig
+++ b/drivers/gpu/drm/tilcdc/Kconfig
@@ -14,3 +14,19 @@ config DRM_TILCDC
controller, for example AM33xx in beagle-bone, DA8xx, or
OMAP-L1xx. This driver replaces the FB_DA8XX fbdev driver.
+config DRM_TILCDC_PANEL_LEGACY
+ bool "Support device tree blobs using TI LCDC Panel binding"
+ default y
+ depends on DRM_TILCDC
+ depends on OF
+ depends on BACKLIGHT_CLASS_DEVICE
+ depends on PM
+ select OF_OVERLAY
+ select DRM_PANEL_SIMPLE
+ help
+ Modifies the live device tree at early boot to convert the legacy
+ "ti,tilcdc,panel" devicetree node to the standard panel-dpi node.
+ This allows to maintain backward compatibility for boards which
+ were using the deprecated tilcdc_panel driver.
+ If you find "ti,tilcdc,panel"-string from your DTB, you probably
+ need this. Otherwise you do not.
diff --git a/drivers/gpu/drm/tilcdc/Makefile b/drivers/gpu/drm/tilcdc/Makefile
index f5190477de721..6d6a08b5adf40 100644
--- a/drivers/gpu/drm/tilcdc/Makefile
+++ b/drivers/gpu/drm/tilcdc/Makefile
@@ -11,3 +11,5 @@ tilcdc-y := \
tilcdc_drv.o
obj-$(CONFIG_DRM_TILCDC) += tilcdc.o
+obj-$(CONFIG_DRM_TILCDC_PANEL_LEGACY) += tilcdc_panel_legacy.o \
+ tilcdc_panel_legacy.dtbo.o
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c
new file mode 100644
index 0000000000000..37a69b3cf04b2
--- /dev/null
+++ b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c
@@ -0,0 +1,185 @@
+// 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);
diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso
new file mode 100644
index 0000000000000..ae71d10f5ec13
--- /dev/null
+++ b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso
@@ -0,0 +1,29 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * DTS overlay for converting ti,tilcdc,panel binding to new binding.
+ *
+ * Copyright (C) 2025 Bootlin
+ * Author: Kory Maincent <kory.maincent@bootlin.com>
+ */
+
+/dts-v1/;
+/plugin/;
+
+&{/} {
+ tilcdc-panel-dpi {
+ compatible = "panel-dpi";
+ port {
+ panel_in: endpoint@0 {
+ remote-endpoint = <&lcd_0>;
+ };
+ };
+ };
+};
+
+&lcdc {
+ port {
+ lcd_0: endpoint@0 {
+ remote-endpoint = <&panel_in>;
+ };
+ };
+};
--
2.43.0On 1/6/26 11:42 AM, Kory Maincent (TI.com) wrote:
> To maintain backward compatibility while removing the deprecated
> tilcdc_panel driver, add a tilcdc_panel_legacy subdriver that converts
> the legacy "ti,tilcdc,panel" devicetree binding to the standard
> panel-dpi binding at early boot.
>
> The conversion uses an embedded device tree overlay that is applied and
> modified during subsys_initcall. The process:
>
> - Apply embedded overlay to create a tilcdc-panel-dpi node with
> port/endpoint connections to the LCDC
> - Copy all properties from the legacy panel node to the new
> tilcdc-panel-dpi node
> - Copy display-timings from the legacy panel
> - Convert legacy panel-info properties (invert-pxl-clk, sync-edge) to
> standard display timing properties (pixelclk-active, syncclk-active)
> - Disable the legacy panel by removing its compatible property to
> prevent the deprecated driver from binding
>
> The result is a standard tilcdc-panel-dpi node with proper endpoints and
> timing properties, allowing the DRM panel infrastructure to work with
> legacy devicetrees without modification.
>
> Other legacy panel-info properties are not migrated as they consistently
> use default values across all mainline devicetrees and can be hardcoded
> in the tilcdc driver.
>
> This feature is optional via CONFIG_DRM_TILCDC_PANEL_LEGACY and should
> only be enabled for systems with legacy devicetrees containing
> "ti,tilcdc,panel" nodes.
>
> Suggested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
> Link: https://lore.kernel.org/all/1d9a9269-bfda-4d43-938b-2df6b82b9369@ideasonboard.com/
> Signed-off-by: Kory Maincent (TI.com) <kory.maincent@bootlin.com>
> ---
>
> Using the approach of applying an overlay and then modifying the live
> device tree is the solution I found that requires no modification of the
> OF core. Dealing entirely with changesets would bring additional
> requirements such as phandle resolution management, which is internal to
> the OF framework. I intend to avoid OF core change to support this legacy
> binding.
>
> Change in v3:
> - Use __free() macro instead of manual house cleaning.
> - Enable CONFIG_DRM_TILCDC_PANEL_LEGACY config by default.
> - Improve config description.
> - Rename "panel-dpi" to "tilcdc-panel-dpi" to avoid any future conflict.
> - Use OF changeset instead of modifying the live devicetree step by
> step.
> - Add kfree to avoid memory leak.
>
> Change in v2:
> - New patch.
> ---
> drivers/gpu/drm/tilcdc/Kconfig | 16 ++
> drivers/gpu/drm/tilcdc/Makefile | 2 +
> drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c | 185 ++++++++++++++++++++++++
> drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso | 29 ++++
> 4 files changed, 232 insertions(+)
>
> diff --git a/drivers/gpu/drm/tilcdc/Kconfig b/drivers/gpu/drm/tilcdc/Kconfig
> index 24f9a245ba593..4fca8058eb7db 100644
> --- a/drivers/gpu/drm/tilcdc/Kconfig
> +++ b/drivers/gpu/drm/tilcdc/Kconfig
> @@ -14,3 +14,19 @@ config DRM_TILCDC
> controller, for example AM33xx in beagle-bone, DA8xx, or
> OMAP-L1xx. This driver replaces the FB_DA8XX fbdev driver.
>
> +config DRM_TILCDC_PANEL_LEGACY
> + bool "Support device tree blobs using TI LCDC Panel binding"
> + default y
> + depends on DRM_TILCDC
> + depends on OF
> + depends on BACKLIGHT_CLASS_DEVICE
> + depends on PM
Spaces -> tabs
> + select OF_OVERLAY
> + select DRM_PANEL_SIMPLE
> + help
> + Modifies the live device tree at early boot to convert the legacy
> + "ti,tilcdc,panel" devicetree node to the standard panel-dpi node.
> + This allows to maintain backward compatibility for boards which
> + were using the deprecated tilcdc_panel driver.
> + If you find "ti,tilcdc,panel"-string from your DTB, you probably
> + need this. Otherwise you do not.
> diff --git a/drivers/gpu/drm/tilcdc/Makefile b/drivers/gpu/drm/tilcdc/Makefile
> index f5190477de721..6d6a08b5adf40 100644
> --- a/drivers/gpu/drm/tilcdc/Makefile
> +++ b/drivers/gpu/drm/tilcdc/Makefile
> @@ -11,3 +11,5 @@ tilcdc-y := \
> tilcdc_drv.o
>
> obj-$(CONFIG_DRM_TILCDC) += tilcdc.o
> +obj-$(CONFIG_DRM_TILCDC_PANEL_LEGACY) += tilcdc_panel_legacy.o \
> + tilcdc_panel_legacy.dtbo.o
> diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c
> new file mode 100644
> index 0000000000000..37a69b3cf04b2
> --- /dev/null
> +++ b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.c
> @@ -0,0 +1,185 @@
> +// 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;
Looking over the users of `of_overlay_fdt_apply()` they all seem
to start with a begin and end address, then have to convert to start
and size. I wonder if this function should be converted to just take
begin and end addresses instead.. (not a problem for this series, just
thinking out loud).
Andrew
> +
> + 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);
> diff --git a/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso
> new file mode 100644
> index 0000000000000..ae71d10f5ec13
> --- /dev/null
> +++ b/drivers/gpu/drm/tilcdc/tilcdc_panel_legacy.dtso
> @@ -0,0 +1,29 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * DTS overlay for converting ti,tilcdc,panel binding to new binding.
> + *
> + * Copyright (C) 2025 Bootlin
> + * Author: Kory Maincent <kory.maincent@bootlin.com>
> + */
> +
> +/dts-v1/;
> +/plugin/;
> +
> +&{/} {
> + tilcdc-panel-dpi {
> + compatible = "panel-dpi";
> + port {
> + panel_in: endpoint@0 {
> + remote-endpoint = <&lcd_0>;
> + };
> + };
> + };
> +};
> +
> +&lcdc {
> + port {
> + lcd_0: endpoint@0 {
> + remote-endpoint = <&panel_in>;
> + };
> + };
> +};
>
On Tue, 6 Jan 2026 13:38:37 -0600 Andrew Davis <afd@ti.com> wrote: > On 1/6/26 11:42 AM, Kory Maincent (TI.com) wrote: > > To maintain backward compatibility while removing the deprecated > > tilcdc_panel driver, add a tilcdc_panel_legacy subdriver that converts > > the legacy "ti,tilcdc,panel" devicetree binding to the standard > > panel-dpi binding at early boot. ... > > + 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; > > Looking over the users of `of_overlay_fdt_apply()` they all seem > to start with a begin and end address, then have to convert to start > and size. I wonder if this function should be converted to just take > begin and end addresses instead.. (not a problem for this series, just > thinking out loud). Indeed, I think you are right. Regards, -- Köry Maincent, Bootlin Embedded Linux and kernel engineering https://bootlin.com
© 2016 - 2026 Red Hat, Inc.