The internal LVDS encoders now have their own DT bindings. Before
switching the driver infrastructure to those new bindings, implement
backward-compatibility through live DT patching.
Patching is disabled and will be enabled along with support for the new
DT bindings in the DU driver.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
---
Changes since v1:
- Select OF_FLATTREE
- Compile LVDS DT bindings patch code when DRM_RCAR_LVDS is selected
- Update the SPDX headers to use GPL-2.0 instead of GPL-2.0-only
- Turn __dtb_rcar_du_of_lvds_(begin|end) from u8 to char
- Pass void begin and end pointers to rcar_du_of_get_overlay()
- Use of_get_parent() instead of accessing the parent pointer directly
- Find the LVDS endpoints nodes based on the LVDS node instead of the
root of the overlay
- Update to the <soc>-lvds compatible string format
---
drivers/gpu/drm/rcar-du/Kconfig | 2 +
drivers/gpu/drm/rcar-du/Makefile | 3 +-
drivers/gpu/drm/rcar-du/rcar_du_of.c | 451 ++++++++++++++++++++++++++++
drivers/gpu/drm/rcar-du/rcar_du_of.h | 16 +
drivers/gpu/drm/rcar-du/rcar_du_of_lvds.dts | 82 +++++
5 files changed, 553 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/rcar-du/rcar_du_of.c
create mode 100644 drivers/gpu/drm/rcar-du/rcar_du_of.h
create mode 100644 drivers/gpu/drm/rcar-du/rcar_du_of_lvds.dts
diff --git a/drivers/gpu/drm/rcar-du/Kconfig b/drivers/gpu/drm/rcar-du/Kconfig
index 5d0b4b7119af..3f83352a7313 100644
--- a/drivers/gpu/drm/rcar-du/Kconfig
+++ b/drivers/gpu/drm/rcar-du/Kconfig
@@ -22,6 +22,8 @@ config DRM_RCAR_LVDS
bool "R-Car DU LVDS Encoder Support"
depends on DRM_RCAR_DU
select DRM_PANEL
+ select OF_FLATTREE
+ select OF_OVERLAY
help
Enable support for the R-Car Display Unit embedded LVDS encoders.
diff --git a/drivers/gpu/drm/rcar-du/Makefile b/drivers/gpu/drm/rcar-du/Makefile
index 0cf5c11030e8..8ed569a0f462 100644
--- a/drivers/gpu/drm/rcar-du/Makefile
+++ b/drivers/gpu/drm/rcar-du/Makefile
@@ -5,10 +5,11 @@ rcar-du-drm-y := rcar_du_crtc.o \
rcar_du_group.o \
rcar_du_kms.o \
rcar_du_lvdscon.o \
+ rcar_du_of.o \
rcar_du_plane.o
rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS) += rcar_du_lvdsenc.o
-
+rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS) += rcar_du_of_lvds.dtb.o
rcar-du-drm-$(CONFIG_DRM_RCAR_VSP) += rcar_du_vsp.o
obj-$(CONFIG_DRM_RCAR_DU) += rcar-du-drm.o
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of.c b/drivers/gpu/drm/rcar-du/rcar_du_of.c
new file mode 100644
index 000000000000..2bf91201fc93
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_du_of.c
@@ -0,0 +1,451 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of.c - Legacy DT bindings compatibility
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+ *
+ * Based on work from Jyri Sarha <jsarha@xxxxxx>
+ * Copyright (C) 2015 Texas Instruments
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_fdt.h>
+#include <linux/of_graph.h>
+#include <linux/slab.h>
+
+#include "rcar_du_crtc.h"
+#include "rcar_du_drv.h"
+
+#ifdef CONFIG_DRM_RCAR_LVDS
+
+struct rcar_du_of_overlay {
+ struct device_node *np;
+ void *data;
+ void *mem;
+};
+
+static void __init rcar_du_of_free_overlay(struct rcar_du_of_overlay *overlay)
+{
+ of_node_put(overlay->np);
+ kfree(overlay->data);
+ kfree(overlay->mem);
+}
+
+static int __init rcar_du_of_get_overlay(struct rcar_du_of_overlay *overlay,
+ void *begin, void *end)
+{
+ const size_t size = end - begin;
+
+ memset(overlay, 0, sizeof(*overlay));
+
+ if (!size)
+ return -EINVAL;
+
+ overlay->data = kmemdup(begin, size, GFP_KERNEL);
+ if (!overlay->data)
+ return -ENOMEM;
+
+ overlay->mem = of_fdt_unflatten_tree(overlay->data, NULL, &overlay->np);
+ if (!overlay->mem) {
+ rcar_du_of_free_overlay(overlay);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static struct device_node __init *
+rcar_du_of_find_node_by_path(struct device_node *parent, const char *path)
+{
+ parent = of_node_get(parent);
+ if (!parent)
+ return NULL;
+
+ while (parent && *path == '/') {
+ struct device_node *child = NULL;
+ struct device_node *node;
+ const char *next;
+ size_t len;
+
+ /* Skip the initial '/' delimiter and find the next one. */
+ path++;
+ next = strchrnul(path, '/');
+ len = next - path;
+ if (!len)
+ goto error;
+
+ for_each_child_of_node(parent, node) {
+ const char *name = kbasename(node->full_name);
+
+ if (strncmp(path, name, len) == 0 &&
+ strlen(name) == len) {
+ child = node;
+ break;
+ }
+ }
+
+ if (!child)
+ goto error;
+
+ of_node_put(parent);
+ parent = child;
+ path = next;
+ }
+
+ return parent;
+
+error:
+ of_node_put(parent);
+ return NULL;
+}
+
+static int __init rcar_du_of_add_property(struct device_node *np,
+ const char *name, const void *value,
+ size_t length)
+{
+ struct property *prop;
+
+ prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+ if (!prop)
+ return -ENOMEM;
+
+ prop->name = kstrdup(name, GFP_KERNEL);
+ prop->value = kmemdup(value, length, GFP_KERNEL);
+ prop->length = length;
+
+ if (!prop->name || !prop->value) {
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+ return -ENOMEM;
+ }
+
+ of_property_set_flag(prop, OF_DYNAMIC);
+
+ prop->next = np->properties;
+ np->properties = prop;
+
+ return 0;
+}
+
+/* Free properties allocated dynamically by rcar_du_of_add_property(). */
+static void __init rcar_du_of_free_properties(struct device_node *np)
+{
+ while (np->properties) {
+ struct property *prop = np->properties;
+
+ np->properties = prop->next;
+
+ if (OF_IS_DYNAMIC(prop)) {
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+ }
+ }
+}
+
+static int __init rcar_du_of_update_target_path(struct device_node *du,
+ struct device_node *remote,
+ struct device_node *np)
+{
+ struct device_node *target = NULL;
+ struct property **prev;
+ struct property *prop;
+ char *path;
+ int ret;
+
+ for (prop = np->properties, prev = ∝ prop != NULL;
+ prev = &prop->next, prop = prop->next) {
+ if (of_prop_cmp(prop->name, "target-path"))
+ continue;
+
+ if (!of_prop_cmp(prop->value, "soc")) {
+ target = of_get_parent(du);
+ break;
+ }
+ if (!of_prop_cmp(prop->value, "du")) {
+ target = of_node_get(du);
+ break;
+ }
+ if (!of_prop_cmp(prop->value, "lvds-sink")) {
+ target = of_graph_get_port_parent(remote);
+ break;
+ }
+
+ return -EINVAL;
+ }
+
+ if (!target)
+ return -EINVAL;
+
+ path = kasprintf(GFP_KERNEL, "%pOF", target);
+ of_node_put(target);
+ if (!path)
+ return -ENOMEM;
+
+ /*
+ * Remove the existing target-path property that has not been
+ * dynamically allocated and replace it with a new dynamic one to
+ * ensure that the value will be properly freed.
+ */
+ *prev = prop->next;
+ ret = rcar_du_of_add_property(np, "target-path", path,
+ strlen(path) + 1);
+ if (ret < 0) {
+ kfree(path);
+ return ret;
+ }
+
+ return 0;
+}
+
+extern char __dtb_rcar_du_of_lvds_begin[];
+extern char __dtb_rcar_du_of_lvds_end[];
+
+static void __init rcar_du_of_lvds_patch_one(struct device_node *du,
+ unsigned int port_id,
+ const struct resource *res,
+ const __be32 *reg,
+ const struct of_phandle_args *clkspec,
+ struct device_node *local,
+ struct device_node *remote)
+{
+ struct rcar_du_of_overlay overlay;
+ struct device_node *du_port_fixup;
+ struct device_node *du_port;
+ struct device_node *lvds_endpoints[2];
+ struct device_node *lvds;
+ struct device_node *fragment;
+ struct device_node *bus;
+ struct property *prop;
+ const char *compatible;
+ const char *soc_suffix;
+ unsigned int psize;
+ unsigned int i;
+ __be32 value[4];
+ char name[23];
+ int ovcs_id;
+ int ret;
+
+ /* Skip if the LVDS node already exists. */
+ sprintf(name, "lvds@%llx", (u64)res->start);
+ bus = of_get_parent(du);
+ lvds = of_get_child_by_name(bus, name);
+ of_node_put(bus);
+ if (lvds) {
+ of_node_put(lvds);
+ return;
+ }
+
+ /* Parse the overlay. */
+ ret = rcar_du_of_get_overlay(&overlay, __dtb_rcar_du_of_lvds_begin,
+ __dtb_rcar_du_of_lvds_end);
+ if (ret < 0)
+ return;
+
+ /*
+ * Patch the LVDS and DU port nodes names and the associated fixup
+ * entries.
+ */
+ lvds = rcar_du_of_find_node_by_path(overlay.np,
+ "/fragment@0/__overlay__/lvds");
+ lvds_endpoints[0] = rcar_du_of_find_node_by_path(lvds,
+ "/ports/port@0/endpoint");
+ lvds_endpoints[1] = rcar_du_of_find_node_by_path(lvds,
+ "/ports/port@1/endpoint");
+ du_port = rcar_du_of_find_node_by_path(overlay.np,
+ "/fragment@1/__overlay__/ports/port@0");
+ du_port_fixup = rcar_du_of_find_node_by_path(overlay.np,
+ "/__local_fixups__/fragment@1/__overlay__/ports/port@0");
+ if (!lvds || !lvds_endpoints[0] || !lvds_endpoints[1] ||
+ !du_port || !du_port_fixup)
+ goto out_put_nodes;
+
+ lvds->full_name = kstrdup(name, GFP_KERNEL);
+
+ sprintf(name, "port@%u", port_id);
+ du_port->full_name = kstrdup(name, GFP_KERNEL);
+ du_port_fixup->full_name = kstrdup(name, GFP_KERNEL);
+
+ if (!lvds->full_name || !du_port->full_name ||
+ !du_port_fixup->full_name)
+ goto out_free_names;
+
+ /* Patch the target paths in all fragments. */
+ for_each_child_of_node(overlay.np, fragment) {
+ if (strncmp("fragment@", of_node_full_name(fragment), 9))
+ continue;
+
+ ret = rcar_du_of_update_target_path(du, remote, fragment);
+ if (ret < 0) {
+ of_node_put(fragment);
+ goto out_free_properties;
+ }
+ }
+
+ /*
+ * Create a compatible string for the LVDS node using the SoC model
+ * from the DU node.
+ */
+ ret = of_property_read_string(du, "compatible", &compatible);
+ if (ret < 0)
+ goto out_free_properties;
+
+ soc_suffix = strchr(compatible, '-');
+ if (!soc_suffix || strlen(soc_suffix) > 10)
+ goto out_free_properties;
+
+ psize = sprintf(name, "renesas,%s-lvds", soc_suffix + 1) + 1;
+ ret = rcar_du_of_add_property(lvds, "compatible", name, psize);
+ if (ret < 0)
+ goto out_free_properties;
+
+ /* Copy the LVDS reg and clocks properties from the DU node. */
+ psize = (of_n_addr_cells(du) + of_n_size_cells(du)) * 4;
+ ret = rcar_du_of_add_property(lvds, "reg", reg, psize);
+ if (ret < 0)
+ goto out_free_properties;
+
+ if (clkspec->args_count >= ARRAY_SIZE(value) - 1)
+ goto out_free_properties;
+
+ value[0] = cpu_to_be32(clkspec->np->phandle);
+ for (i = 0; i < clkspec->args_count; ++i)
+ value[i + 1] = cpu_to_be32(clkspec->args[i]);
+
+ psize = (clkspec->args_count + 1) * 4;
+ ret = rcar_du_of_add_property(lvds, "clocks", value, psize);
+ if (ret < 0)
+ goto out_free_properties;
+
+ /*
+ * Insert the node in the OF graph: patch the LVDS ports remote-endpoint
+ * properties to point to the endpoints of the sibling nodes in the
+ * graph.
+ */
+ prop = of_find_property(lvds_endpoints[0], "remote-endpoint", NULL);
+ if (!prop)
+ goto out_free_properties;
+
+ *(__be32 *)prop->value = cpu_to_be32(local->phandle);
+
+ prop = of_find_property(lvds_endpoints[1], "remote-endpoint", NULL);
+ if (!prop)
+ goto out_free_properties;
+
+ *(__be32 *)prop->value = cpu_to_be32(remote->phandle);
+
+ /* Apply the overlay, this will resolve phandles. */
+ ovcs_id = 0;
+ ret = of_overlay_apply(overlay.np, &ovcs_id);
+
+ /* We're done, free all allocated memory. */
+out_free_properties:
+ rcar_du_of_free_properties(lvds);
+ rcar_du_of_free_properties(du_port);
+ rcar_du_of_free_properties(du_port_fixup);
+out_free_names:
+ kfree(lvds->full_name);
+ kfree(du_port->full_name);
+ kfree(du_port_fixup->full_name);
+out_put_nodes:
+ of_node_put(lvds);
+ of_node_put(lvds_endpoints[0]);
+ of_node_put(lvds_endpoints[1]);
+ of_node_put(du_port);
+ of_node_put(du_port_fixup);
+
+ rcar_du_of_free_overlay(&overlay);
+}
+
+static void __init rcar_du_of_lvds_patch(const struct of_device_id *of_ids)
+{
+ const struct rcar_du_device_info *info;
+ const struct of_device_id *match;
+ struct device_node *du;
+ unsigned int i;
+ int ret;
+
+ /* Get the DU node and exit if not present or disabled. */
+ du = of_find_matching_node_and_match(NULL, of_ids, &match);
+ if (!du || !of_device_is_available(du))
+ goto done;
+
+ info = match->data;
+
+ /* Patch every LVDS encoder. */
+ for (i = 0; i < info->num_lvds; ++i) {
+ struct of_phandle_args clkspec;
+ struct device_node *local, *remote;
+ struct resource res;
+ unsigned int port_id;
+ const __be32 *reg;
+ char name[7];
+ int index;
+
+ /*
+ * Retrieve the register specifier, the clock specifier and the
+ * local and remote endpoints of the LVDS link.
+ */
+ sprintf(name, "lvds.%u", i);
+ index = of_property_match_string(du, "reg-names", name);
+ if (index < 0)
+ continue;
+
+ reg = of_get_address(du, index, NULL, NULL);
+ if (!reg)
+ continue;
+
+ ret = of_address_to_resource(du, index, &res);
+ if (ret < 0)
+ continue;
+
+ index = of_property_match_string(du, "clock-names", name);
+ if (index < 0)
+ continue;
+
+ ret = of_parse_phandle_with_args(du, "clocks", "#clock-cells",
+ index, &clkspec);
+ if (ret < 0)
+ continue;
+
+ port_id = info->routes[RCAR_DU_OUTPUT_LVDS0 + i].port;
+
+ local = of_graph_get_endpoint_by_regs(du, port_id, 0);
+ if (!local) {
+ of_node_put(clkspec.np);
+ continue;
+ }
+
+ remote = of_graph_get_remote_endpoint(local);
+ if (!remote) {
+ of_node_put(local);
+ of_node_put(clkspec.np);
+ continue;
+ }
+
+ /* Patch the LVDS encoder. */
+ rcar_du_of_lvds_patch_one(du, port_id, &res, reg, &clkspec,
+ local, remote);
+
+ of_node_put(clkspec.np);
+ of_node_put(remote);
+ of_node_put(local);
+ }
+
+done:
+ of_node_put(du);
+}
+#else
+static void __init rcar_du_of_lvds_patch(const struct of_device_id *of_ids)
+{
+}
+#endif /* CONFIG_DRM_RCAR_LVDS */
+
+void __init rcar_du_of_init(const struct of_device_id *of_ids)
+{
+ rcar_du_of_lvds_patch(of_ids);
+}
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of.h b/drivers/gpu/drm/rcar-du/rcar_du_of.h
new file mode 100644
index 000000000000..7105eaef58c6
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_du_of.h
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of.h - Legacy DT bindings compatibility
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+ */
+#ifndef __RCAR_DU_OF_H__
+#define __RCAR_DU_OF_H__
+
+#include <linux/init.h>
+
+struct of_device_id;
+
+void __init rcar_du_of_init(const struct of_device_id *of_ids);
+
+#endif /* __RCAR_DU_OF_H__ */
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds.dts
new file mode 100644
index 000000000000..bc75c7a1c3bd
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds.dts
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds.dts - Legacy LVDS DT bindings conversion
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+ *
+ * Based on work from Jyri Sarha <jsarha@xxxxxx>
+ * Copyright (C) 2015 Texas Instruments
+ */
+
+/*
+ * The target-paths, lvds node name, DU port number and LVDS remote endpoints
+ * will be patched dynamically at runtime.
+ */
+
+/dts-v1/;
+/ {
+ fragment@0 {
+ target-path = "soc";
+ __overlay__ {
+ lvds {
+ ports {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ port@0 {
+ reg = <0>;
+ lvds_input: endpoint {
+ remote-endpoint = <0>;
+ };
+ };
+
+ port@1 {
+ reg = <1>;
+ lvds_output: endpoint {
+ remote-endpoint = <0>;
+ };
+ };
+ };
+ };
+ };
+ };
+
+ fragment@1 {
+ target-path = "du";
+ __overlay__ {
+ ports {
+ port@0 {
+ endpoint {
+ remote-endpoint = <&lvds_input>;
+ };
+ };
+ };
+ };
+ };
+
+ fragment@2 {
+ target-path = "lvds-sink";
+ __overlay__ {
+ remote-endpoint = <&lvds_output>;
+ };
+ };
+
+ __local_fixups__ {
+ fragment@1 {
+ __overlay__ {
+ ports {
+ port@0 {
+ endpoint {
+ remote-endpoint = <0>;
+ };
+ };
+ };
+ };
+ };
+ fragment@2 {
+ __overlay__ {
+ remote-endpoint = <0>;
+ };
+ };
+ };
+};
--
Regards,
Laurent Pinchart
