drm: rcar-du: Fix legacy DT to create LVDS encoder nodes
authorLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Wed, 10 Jan 2018 00:40:27 +0000 (02:40 +0200)
committerLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Wed, 7 Mar 2018 16:06:41 +0000 (18:06 +0200)
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@ideasonboard.com>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
drivers/gpu/drm/rcar-du/Kconfig
drivers/gpu/drm/rcar-du/Makefile
drivers/gpu/drm/rcar-du/rcar_du_of.c [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of.h [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7790.dts [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7791.dts [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7793.dts [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7795.dts [new file with mode: 0644]
drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7796.dts [new file with mode: 0644]

index 5d0b4b7..3f83352 100644 (file)
@@ -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.
 
index 0cf5c11..86b337b 100644 (file)
@@ -8,7 +8,12 @@ rcar-du-drm-y := rcar_du_crtc.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.o \
+                                          rcar_du_of_lvds_r8a7790.dtb.o \
+                                          rcar_du_of_lvds_r8a7791.dtb.o \
+                                          rcar_du_of_lvds_r8a7793.dtb.o \
+                                          rcar_du_of_lvds_r8a7795.dtb.o \
+                                          rcar_du_of_lvds_r8a7796.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 (file)
index 0000000..68a0b82
--- /dev/null
@@ -0,0 +1,322 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of.c - Legacy DT bindings compatibility
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ *
+ * Based on work from Jyri Sarha <jsarha@ti.com>
+ * 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"
+
+/* -----------------------------------------------------------------------------
+ * Generic Overlay Handling
+ */
+
+struct rcar_du_of_overlay {
+       const char *compatible;
+       void *begin;
+       void *end;
+};
+
+#define RCAR_DU_OF_DTB(type, soc)                                      \
+       extern char __dtb_rcar_du_of_##type##_##soc##_begin[];          \
+       extern char __dtb_rcar_du_of_##type##_##soc##_end[]
+
+#define RCAR_DU_OF_OVERLAY(type, soc)                                  \
+       {                                                               \
+               .compatible = "renesas,du-" #soc,                       \
+               .begin = __dtb_rcar_du_of_##type##_##soc##_begin,       \
+               .end = __dtb_rcar_du_of_##type##_##soc##_end,           \
+       }
+
+static int __init rcar_du_of_apply_overlay(const struct rcar_du_of_overlay *dtbs,
+                                          const char *compatible)
+{
+       const struct rcar_du_of_overlay *dtb = NULL;
+       unsigned int i;
+       int ovcs_id;
+
+       for (i = 0; dtbs[i].compatible; ++i) {
+               if (!strcmp(dtbs[i].compatible, compatible)) {
+                       dtb = &dtbs[i];
+                       break;
+               }
+       }
+
+       if (!dtb)
+               return -ENODEV;
+
+       ovcs_id = 0;
+       return of_overlay_fdt_apply(dtb->begin, dtb->end - dtb->begin,
+                                   &ovcs_id);
+}
+
+static int __init rcar_du_of_add_property(struct of_changeset *ocs,
+                                         struct device_node *np,
+                                         const char *name, const void *value,
+                                         int length)
+{
+       struct property *prop;
+       int ret = -ENOMEM;
+
+       prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+       if (!prop)
+               return -ENOMEM;
+
+       prop->name = kstrdup(name, GFP_KERNEL);
+       if (!prop->name)
+               goto out_err;
+
+       prop->value = kmemdup(value, length, GFP_KERNEL);
+       if (!prop->value)
+               goto out_err;
+
+       of_property_set_flag(prop, OF_DYNAMIC);
+
+       prop->length = length;
+
+       ret = of_changeset_add_property(ocs, np, prop);
+       if (!ret)
+               return 0;
+
+out_err:
+       kfree(prop->value);
+       kfree(prop->name);
+       kfree(prop);
+       return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ * LVDS Overlays
+ */
+
+RCAR_DU_OF_DTB(lvds, r8a7790);
+RCAR_DU_OF_DTB(lvds, r8a7791);
+RCAR_DU_OF_DTB(lvds, r8a7793);
+RCAR_DU_OF_DTB(lvds, r8a7795);
+RCAR_DU_OF_DTB(lvds, r8a7796);
+
+static const struct rcar_du_of_overlay rcar_du_lvds_overlays[] __initconst = {
+       RCAR_DU_OF_OVERLAY(lvds, r8a7790),
+       RCAR_DU_OF_OVERLAY(lvds, r8a7791),
+       RCAR_DU_OF_OVERLAY(lvds, r8a7793),
+       RCAR_DU_OF_OVERLAY(lvds, r8a7795),
+       RCAR_DU_OF_OVERLAY(lvds, r8a7796),
+       { /* Sentinel */ },
+};
+
+static struct of_changeset rcar_du_lvds_changeset;
+
+static void __init rcar_du_of_lvds_patch_one(struct device_node *lvds,
+                                            const struct of_phandle_args *clk,
+                                            struct device_node *local,
+                                            struct device_node *remote)
+{
+       unsigned int psize;
+       unsigned int i;
+       __be32 value[4];
+       int ret;
+
+       /*
+        * Set the LVDS clocks property. This can't be performed by the overlay
+        * as the structure of the clock specifier has changed over time, and we
+        * don't know at compile time which binding version the system we will
+        * run on uses.
+        */
+       if (clk->args_count >= ARRAY_SIZE(value) - 1)
+               return;
+
+       of_changeset_init(&rcar_du_lvds_changeset);
+
+       value[0] = cpu_to_be32(clk->np->phandle);
+       for (i = 0; i < clk->args_count; ++i)
+               value[i + 1] = cpu_to_be32(clk->args[i]);
+
+       psize = (clk->args_count + 1) * 4;
+       ret = rcar_du_of_add_property(&rcar_du_lvds_changeset, lvds,
+                                     "clocks", value, psize);
+       if (ret < 0)
+               goto done;
+
+       /*
+        * 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. This can't be performed by the overlay: on the input side the
+        * overlay would contain a phandle for the DU LVDS output port that
+        * would clash with the system DT, and on the output side the connection
+        * is board-specific.
+        */
+       value[0] = cpu_to_be32(local->phandle);
+       value[1] = cpu_to_be32(remote->phandle);
+
+       for (i = 0; i < 2; ++i) {
+               struct device_node *endpoint;
+
+               endpoint = of_graph_get_endpoint_by_regs(lvds, i, 0);
+               if (!endpoint) {
+                       ret = -EINVAL;
+                       goto done;
+               }
+
+               ret = rcar_du_of_add_property(&rcar_du_lvds_changeset,
+                                             endpoint, "remote-endpoint",
+                                             &value[i], sizeof(value[i]));
+               of_node_put(endpoint);
+               if (ret < 0)
+                       goto done;
+       }
+
+       ret = of_changeset_apply(&rcar_du_lvds_changeset);
+
+done:
+       if (ret < 0)
+               of_changeset_destroy(&rcar_du_lvds_changeset);
+}
+
+struct lvds_of_data {
+       struct resource res;
+       struct of_phandle_args clkspec;
+       struct device_node *local;
+       struct device_node *remote;
+};
+
+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 lvds_of_data lvds_data[2] = { };
+       struct device_node *lvds_node;
+       struct device_node *soc_node;
+       struct device_node *du_node;
+       char compatible[22];
+       const char *soc_name;
+       unsigned int i;
+       int ret;
+
+       /* Get the DU node and exit if not present or disabled. */
+       du_node = of_find_matching_node_and_match(NULL, of_ids, &match);
+       if (!du_node || !of_device_is_available(du_node)) {
+               of_node_put(du_node);
+               return;
+       }
+
+       info = match->data;
+       soc_node = of_get_parent(du_node);
+
+       if (WARN_ON(info->num_lvds > ARRAY_SIZE(lvds_data)))
+               goto done;
+
+       /*
+        * Skip if the LVDS nodes already exists.
+        *
+        * The nodes are searched based on the compatible string, which we
+        * construct from the SoC name found in the DU compatible string. As a
+        * match has been found we know the compatible string matches the
+        * expected format and can thus skip some of the string manipulation
+        * normal safety checks.
+        */
+       soc_name = strchr(match->compatible, '-') + 1;
+       sprintf(compatible, "renesas,%s-lvds", soc_name);
+       lvds_node = of_find_compatible_node(NULL, NULL, compatible);
+       if (lvds_node) {
+               of_node_put(lvds_node);
+               return;
+       }
+
+       /*
+        * Parse the DU node and store the register specifier, the clock
+        * specifier and the local and remote endpoint of the LVDS link for
+        * later use.
+        */
+       for (i = 0; i < info->num_lvds; ++i) {
+               struct lvds_of_data *lvds = &lvds_data[i];
+               unsigned int port;
+               char name[7];
+               int index;
+
+               sprintf(name, "lvds.%u", i);
+               index = of_property_match_string(du_node, "clock-names", name);
+               if (index < 0)
+                       continue;
+
+               ret = of_parse_phandle_with_args(du_node, "clocks",
+                                                "#clock-cells", index,
+                                                &lvds->clkspec);
+               if (ret < 0)
+                       continue;
+
+               port = info->routes[RCAR_DU_OUTPUT_LVDS0 + i].port;
+
+               lvds->local = of_graph_get_endpoint_by_regs(du_node, port, 0);
+               if (!lvds->local)
+                       continue;
+
+               lvds->remote = of_graph_get_remote_endpoint(lvds->local);
+               if (!lvds->remote)
+                       continue;
+
+               index = of_property_match_string(du_node, "reg-names", name);
+               if (index < 0)
+                       continue;
+
+               of_address_to_resource(du_node, index, &lvds->res);
+       }
+
+       /* Parse and apply the overlay. This will resolve phandles. */
+       ret = rcar_du_of_apply_overlay(rcar_du_lvds_overlays,
+                                      match->compatible);
+       if (ret < 0)
+               goto done;
+
+       /* Patch the newly created LVDS encoder nodes. */
+       for_each_child_of_node(soc_node, lvds_node) {
+               struct resource res;
+
+               if (!of_device_is_compatible(lvds_node, compatible))
+                       continue;
+
+               /* Locate the lvds_data entry based on the resource start. */
+               ret = of_address_to_resource(lvds_node, 0, &res);
+               if (ret < 0)
+                       continue;
+
+               for (i = 0; i < ARRAY_SIZE(lvds_data); ++i) {
+                       if (lvds_data[i].res.start == res.start)
+                               break;
+               }
+
+               if (i == ARRAY_SIZE(lvds_data))
+                       continue;
+
+               /* Patch the LVDS encoder. */
+               rcar_du_of_lvds_patch_one(lvds_node, &lvds_data[i].clkspec,
+                                         lvds_data[i].local,
+                                         lvds_data[i].remote);
+       }
+
+done:
+       for (i = 0; i < info->num_lvds; ++i) {
+               of_node_put(lvds_data[i].clkspec.np);
+               of_node_put(lvds_data[i].local);
+               of_node_put(lvds_data[i].remote);
+       }
+
+       of_node_put(soc_node);
+       of_node_put(du_node);
+}
+
+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 (file)
index 0000000..c2e65a7
--- /dev/null
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * rcar_du_of.h - Legacy DT bindings compatibility
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+#ifndef __RCAR_DU_OF_H__
+#define __RCAR_DU_OF_H__
+
+#include <linux/init.h>
+
+struct of_device_id;
+
+#ifdef CONFIG_DRM_RCAR_LVDS
+void __init rcar_du_of_init(const struct of_device_id *of_ids);
+#else
+static inline void rcar_du_of_init(const struct of_device_id *of_ids) { }
+#endif /* CONFIG_DRM_RCAR_LVDS */
+
+#endif /* __RCAR_DU_OF_H__ */
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7790.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7790.dts
new file mode 100644 (file)
index 0000000..579753e
--- /dev/null
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds_r8a7790.dts - Legacy LVDS DT bindings conversion for R8A7790
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+/dts-v1/;
+/plugin/;
+/ {
+       fragment@0 {
+               target-path = "/";
+               __overlay__ {
+                       #address-cells = <2>;
+                       #size-cells = <2>;
+
+                       lvds@feb90000 {
+                               compatible = "renesas,r8a7790-lvds";
+                               reg = <0 0xfeb90000 0 0x1c>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds0_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds0_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+
+                       lvds@feb94000 {
+                               compatible = "renesas,r8a7790-lvds";
+                               reg = <0 0xfeb94000 0 0x1c>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds1_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds1_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+               };
+       };
+
+       fragment@1 {
+               target-path = "/display@feb00000/ports";
+               __overlay__ {
+                       port@1 {
+                               endpoint {
+                                       remote-endpoint = <&lvds0_input>;
+                               };
+                       };
+                       port@2 {
+                               endpoint {
+                                       remote-endpoint = <&lvds1_input>;
+                               };
+                       };
+               };
+       };
+};
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7791.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7791.dts
new file mode 100644 (file)
index 0000000..cb9da1f
--- /dev/null
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds_r8a7791.dts - Legacy LVDS DT bindings conversion for R8A7791
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+/dts-v1/;
+/plugin/;
+/ {
+       fragment@0 {
+               target-path = "/";
+               __overlay__ {
+                       #address-cells = <2>;
+                       #size-cells = <2>;
+
+                       lvds@feb90000 {
+                               compatible = "renesas,r8a7791-lvds";
+                               reg = <0 0xfeb90000 0 0x1c>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds0_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds0_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+               };
+       };
+
+       fragment@1 {
+               target-path = "/display@feb00000/ports";
+               __overlay__ {
+                       port@1 {
+                               endpoint {
+                                       remote-endpoint = <&lvds0_input>;
+                               };
+                       };
+               };
+       };
+};
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7793.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7793.dts
new file mode 100644 (file)
index 0000000..e7b8804
--- /dev/null
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds_r8a7793.dts - Legacy LVDS DT bindings conversion for R8A7793
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+/dts-v1/;
+/plugin/;
+/ {
+       fragment@0 {
+               target-path = "/";
+               __overlay__ {
+                       #address-cells = <2>;
+                       #size-cells = <2>;
+
+                       lvds@feb90000 {
+                               compatible = "renesas,r8a7793-lvds";
+                               reg = <0 0xfeb90000 0 0x1c>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds0_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds0_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+               };
+       };
+
+       fragment@1 {
+               target-path = "/display@feb00000/ports";
+               __overlay__ {
+                       port@1 {
+                               endpoint {
+                                       remote-endpoint = <&lvds0_input>;
+                               };
+                       };
+               };
+       };
+};
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7795.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7795.dts
new file mode 100644 (file)
index 0000000..a132744
--- /dev/null
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds_r8a7795.dts - Legacy LVDS DT bindings conversion for R8A7795
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+/dts-v1/;
+/plugin/;
+/ {
+       fragment@0 {
+               target-path = "/soc";
+               __overlay__ {
+                       #address-cells = <2>;
+                       #size-cells = <2>;
+
+                       lvds@feb90000 {
+                               compatible = "renesas,r8a7795-lvds";
+                               reg = <0 0xfeb90000 0 0x14>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds0_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds0_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+               };
+       };
+
+       fragment@1 {
+               target-path = "/soc/display@feb00000/ports";
+               __overlay__ {
+                       port@3 {
+                               endpoint {
+                                       remote-endpoint = <&lvds0_input>;
+                               };
+                       };
+               };
+       };
+};
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7796.dts b/drivers/gpu/drm/rcar-du/rcar_du_of_lvds_r8a7796.dts
new file mode 100644 (file)
index 0000000..b23d646
--- /dev/null
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_of_lvds_r8a7796.dts - Legacy LVDS DT bindings conversion for R8A7796
+ *
+ * Copyright (C) 2018 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+/dts-v1/;
+/plugin/;
+/ {
+       fragment@0 {
+               target-path = "/soc";
+               __overlay__ {
+                       #address-cells = <2>;
+                       #size-cells = <2>;
+
+                       lvds@feb90000 {
+                               compatible = "renesas,r8a7796-lvds";
+                               reg = <0 0xfeb90000 0 0x14>;
+
+                               ports {
+                                       #address-cells = <1>;
+                                       #size-cells = <0>;
+
+                                       port@0 {
+                                               reg = <0>;
+                                               lvds0_input: endpoint {
+                                               };
+                                       };
+                                       port@1 {
+                                               reg = <1>;
+                                               lvds0_out: endpoint {
+                                               };
+                                       };
+                               };
+                       };
+               };
+       };
+
+       fragment@1 {
+               target-path = "/soc/display@feb00000/ports";
+               __overlay__ {
+                       port@3 {
+                               endpoint {
+                                       remote-endpoint = <&lvds0_input>;
+                               };
+                       };
+               };
+       };
+};