x86, olpc: Use device tree for platform identification

Make OLPC fully depend on device tree, and use it to identify the OLPC
platform details. Some nodes are exposed as platform devices where we
plan to use device tree for device probing.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
LKML-Reference: <20110313151017.C255F9D401E@zog.reactivated.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

3 files changed, 47 insertions, 27 deletions

diff --git a/arch/x86/platform/olpc/Makefile b/arch/x86/platform/olpc/Makefile
index c2a8cab..81c5e21 100644
--- a/arch/x86/platform/olpc/Makefile
+++ b/arch/x86/platform/olpc/Makefile
@@ -1,4 +1,2 @@
-obj-$(CONFIG_OLPC)		+= olpc.o
+obj-$(CONFIG_OLPC)		+= olpc.o olpc_ofw.o olpc_dt.o
 obj-$(CONFIG_OLPC_XO1)		+= olpc-xo1.o
-obj-$(CONFIG_OLPC)		+= olpc_ofw.o
-obj-$(CONFIG_OF_PROMTREE)	+= olpc_dt.o
diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index edaf3fe..0060fd5 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -18,6 +18,7 @@
 #include <linux/io.h>
 #include <linux/string.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
 
 #include <asm/geode.h>
 #include <asm/setup.h>
@@ -187,41 +188,43 @@ err:
 }
 EXPORT_SYMBOL_GPL(olpc_ec_cmd);
 
-static bool __init check_ofw_architecture(void)
+static bool __init check_ofw_architecture(struct device_node *root)
 {
-	size_t propsize;
-	char olpc_arch[5];
-	const void *args[] = { NULL, "architecture", olpc_arch, (void *)5 };
-	void *res[] = { &propsize };
+	const char *olpc_arch;
+	int propsize;
 
-	if (olpc_ofw("getprop", args, res)) {
-		printk(KERN_ERR "ofw: getprop call failed!\n");
-		return false;
-	}
+	olpc_arch = of_get_property(root, "architecture", &propsize);
 	return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
 }
 
-static u32 __init get_board_revision(void)
+static u32 __init get_board_revision(struct device_node *root)
 {
-	size_t propsize;
-	__be32 rev;
-	const void *args[] = { NULL, "board-revision-int", &rev, (void *)4 };
-	void *res[] = { &propsize };
-
-	if (olpc_ofw("getprop", args, res) || propsize != 4) {
-		printk(KERN_ERR "ofw: getprop call failed!\n");
-		return cpu_to_be32(0);
-	}
-	return be32_to_cpu(rev);
+	int propsize;
+	const __be32 *rev;
+
+	rev = of_get_property(root, "board-revision-int", &propsize);
+	if (propsize != 4)
+		return 0;
+
+	return be32_to_cpu(*rev);
 }
 
 static bool __init platform_detect(void)
 {
-	if (!check_ofw_architecture())
+	struct device_node *root = of_find_node_by_path("/");
+	bool success;
+
+	if (!root)
 		return false;
-	olpc_platform_info.flags |= OLPC_F_PRESENT;
-	olpc_platform_info.boardrev = get_board_revision();
-	return true;
+
+	success = check_ofw_architecture(root);
+	if (success) {
+		olpc_platform_info.boardrev = get_board_revision(root);
+		olpc_platform_info.flags |= OLPC_F_PRESENT;
+	}
+
+	of_node_put(root);
+	return success;
 }
 
 static int __init add_xo1_platform_devices(void)
diff --git a/arch/x86/platform/olpc/olpc_dt.c b/arch/x86/platform/olpc/olpc_dt.c
index dab8746..4ce208f 100644
--- a/arch/x86/platform/olpc/olpc_dt.c
+++ b/arch/x86/platform/olpc/olpc_dt.c
@@ -19,7 +19,9 @@
 #include <linux/kernel.h>
 #include <linux/bootmem.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/of_pdt.h>
+#include <asm/olpc.h>
 #include <asm/olpc_ofw.h>
 
 static phandle __init olpc_dt_getsibling(phandle node)
@@ -181,3 +183,20 @@ void __init olpc_dt_build_devicetree(void)
 	pr_info("PROM DT: Built device tree with %u bytes of memory.\n",
 			prom_early_allocated);
 }
+
+/* A list of DT node/bus matches that we want to expose as platform devices */
+static struct of_device_id __initdata of_ids[] = {
+	{ .compatible = "olpc,xo1-battery" },
+	{ .compatible = "olpc,xo1-dcon" },
+	{ .compatible = "olpc,xo1-rtc" },
+	{},
+};
+
+static int __init olpc_create_platform_devices(void)
+{
+	if (machine_is_olpc())
+		return of_platform_bus_probe(NULL, of_ids, NULL);
+	else
+		return 0;
+}
+device_initcall(olpc_create_platform_devices);