1 files changed, 225 insertions, 0 deletions

diff --git a/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
new file mode 100644
index 000000000000..136d30484d02
--- /dev/null
+++ b/drivers/gpu/drm/omapdrm/dss/omapdss-boot-init.c
@@ -0,0 +1,225 @@
+/*
+ * Copyright (C) 2014 Texas Instruments
+ * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ * As omapdss panel drivers are omapdss specific, but we want to define the
+ * DT-data in generic manner, we convert the compatible strings of the panel and
+ * encoder nodes from "panel-foo" to "omapdss,panel-foo". This way we can have
+ * both correct DT data and omapdss specific drivers.
+ *
+ * When we get generic panel drivers to the kernel, this file will be removed.
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+
+static struct list_head dss_conv_list __initdata;
+
+static const char prefix[] __initconst = "omapdss,";
+
+struct dss_conv_node {
+        struct list_head list;
+        struct device_node *node;
+        bool root;
+};
+
+static int __init omapdss_count_strings(const struct property *prop)
+{
+        const char *p = prop->value;
+        int l = 0, total = 0;
+        int i;
+
+        for (i = 0; total < prop->length; total += l, p += l, i++)
+                l = strlen(p) + 1;
+
+        return i;
+}
+
+static void __init omapdss_update_prop(struct device_node *node, char *compat,
+        int len)
+{
+        struct property *prop;
+
+        prop = kzalloc(sizeof(*prop), GFP_KERNEL);
+        if (!prop)
+                return;
+
+        prop->name = "compatible";
+        prop->value = compat;
+        prop->length = len;
+
+        of_update_property(node, prop);
+}
+
+static void __init omapdss_prefix_strcpy(char *dst, int dst_len,
+        const char *src, int src_len)
+{
+        size_t total = 0;
+
+        while (total < src_len) {
+                size_t l = strlen(src) + 1;
+
+                strcpy(dst, prefix);
+                dst += strlen(prefix);
+
+                strcpy(dst, src);
+                dst += l;
+
+                src += l;
+                total += l;
+        }
+}
+
+/* prepend compatible property strings with "omapdss," */
+static void __init omapdss_omapify_node(struct device_node *node)
+{
+        struct property *prop;
+        char *new_compat;
+        int num_strs;
+        int new_len;
+
+        prop = of_find_property(node, "compatible", NULL);
+
+        if (!prop || !prop->value)
+                return;
+
+        if (strnlen(prop->value, prop->length) >= prop->length)
+                return;
+
+        /* is it already prefixed? */
+        if (strncmp(prefix, prop->value, strlen(prefix)) == 0)
+                return;
+
+        num_strs = omapdss_count_strings(prop);
+
+        new_len = prop->length + strlen(prefix) * num_strs;
+        new_compat = kmalloc(new_len, GFP_KERNEL);
+
+        omapdss_prefix_strcpy(new_compat, new_len, prop->value, prop->length);
+
+        omapdss_update_prop(node, new_compat, new_len);
+}
+
+static void __init omapdss_add_to_list(struct device_node *node, bool root)
+{
+        struct dss_conv_node *n = kmalloc(sizeof(struct dss_conv_node),
+                GFP_KERNEL);
+        if (n) {
+                n->node = node;
+                n->root = root;
+                list_add(&n->list, &dss_conv_list);
+        }
+}
+
+static bool __init omapdss_list_contains(const struct device_node *node)
+{
+        struct dss_conv_node *n;
+
+        list_for_each_entry(n, &dss_conv_list, list) {
+                if (n->node == node)
+                        return true;
+        }
+
+        return false;
+}
+
+static void __init omapdss_walk_device(struct device_node *node, bool root)
+{
+        struct device_node *n;
+
+        omapdss_add_to_list(node, root);
+
+        /*
+         * of_graph_get_remote_port_parent() prints an error if there is no
+         * port/ports node. To avoid that, check first that there's the node.
+         */
+        n = of_get_child_by_name(node, "ports");
+        if (!n)
+                n = of_get_child_by_name(node, "port");
+        if (!n)
+                return;
+
+        of_node_put(n);
+
+        n = NULL;
+        while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
+                struct device_node *pn;
+
+                pn = of_graph_get_remote_port_parent(n);
+
+                if (!pn)
+                        continue;
+
+                if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
+                        of_node_put(pn);
+                        continue;
+                }
+
+                omapdss_walk_device(pn, false);
+        }
+}
+
+static const struct of_device_id omapdss_of_match[] __initconst = {
+        { .compatible = "ti,omap2-dss", },
+        { .compatible = "ti,omap3-dss", },
+        { .compatible = "ti,omap4-dss", },
+        { .compatible = "ti,omap5-dss", },
+        { .compatible = "ti,dra7-dss", },
+        {},
+};
+
+static int __init omapdss_boot_init(void)
+{
+        struct device_node *dss, *child;
+
+        INIT_LIST_HEAD(&dss_conv_list);
+
+        dss = of_find_matching_node(NULL, omapdss_of_match);
+
+        if (dss == NULL || !of_device_is_available(dss))
+                return 0;
+
+        omapdss_walk_device(dss, true);
+
+        for_each_available_child_of_node(dss, child) {
+                if (!of_find_property(child, "compatible", NULL))
+                        continue;
+
+                omapdss_walk_device(child, true);
+        }
+
+        while (!list_empty(&dss_conv_list)) {
+                struct dss_conv_node *n;
+
+                n = list_first_entry(&dss_conv_list, struct dss_conv_node,
+                        list);
+
+                if (!n->root)
+                        omapdss_omapify_node(n->node);
+
+                list_del(&n->list);
+                of_node_put(n->node);
+                kfree(n);
+        }
+
+        return 0;
+}
+
+subsys_initcall(omapdss_boot_init);