[PATCH/RFC 06/10] iommu/ipmmu-vmsa: Also use IOMMU_OF_DECLARE()

[Magnus Damm <magnus.damm@gmail.com>]

From: Magnus Damm <damm+renesas@opensource.se>

Hook up IOMMU_OF_DECLARE() support. The default case
has the use_of_iommu feature disabled so the init
order remains unchanged for the default case.

Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
---

 drivers/iommu/ipmmu-vmsa.c |   35 ++++++++++++++++++++++++++++++++++-
 1 file changed, 34 insertions(+), 1 deletion(-)

--- 0016/drivers/iommu/ipmmu-vmsa.c
+++ work/drivers/iommu/ipmmu-vmsa.c	2015-12-15 21:19:31.090513000 +0900
@@ -18,6 +18,8 @@
 #include <linux/iommu.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_iommu.h>
+#include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
@@ -36,6 +38,7 @@ struct ipmmu_features {
 	bool has_cache_leaf_nodes;
 	bool setup_imbuscr;
 	bool twobit_imttbcr_sl0;
+	bool use_of_iommu;
 };
 
 struct ipmmu_vmsa_device {
@@ -891,6 +894,7 @@ static const struct ipmmu_features ipmmu
 	.has_cache_leaf_nodes = false,
 	.setup_imbuscr = true,
 	.twobit_imttbcr_sl0 = false,
+	.use_of_iommu = false,
 };
 
 static const struct of_device_id ipmmu_of_ids[] = {
@@ -1015,15 +1019,21 @@ static struct platform_driver ipmmu_driv
 
 static int __init ipmmu_init(void)
 {
+	static bool setup_done;
 	int ret;
 
+	if (setup_done)
+		return 0;
+
 	ret = platform_driver_register(&ipmmu_driver);
 	if (ret < 0)
 		return ret;
 
+#ifdef CONFIG_ARM
 	if (!iommu_present(&platform_bus_type))
 		bus_set_iommu(&platform_bus_type, &ipmmu_ops);
-
+#endif
+	setup_done = true;
 	return 0;
 }
 
@@ -1035,6 +1045,29 @@ static void __exit ipmmu_exit(void)
 subsys_initcall(ipmmu_init);
 module_exit(ipmmu_exit);
 
+static int __init ipmmu_vmsa_iommu_of_setup(struct device_node *np)
+{
+	const struct of_device_id *match;
+	const struct ipmmu_features *feature;
+	static const struct iommu_ops *ops = &ipmmu_ops;
+
+	ipmmu_init();
+
+	match = of_match_node(ipmmu_of_ids, np);
+	if (match) {
+		feature = match->data;
+		if (feature->use_of_iommu) {
+			of_iommu_set_ops(np, (struct iommu_ops *)ops);
+			if (!iommu_present(&platform_bus_type))
+				bus_set_iommu(&platform_bus_type, ops);
+		}
+	}
+	return 0;
+}
+
+IOMMU_OF_DECLARE(ipmmu_vmsa_iommu_of, "renesas,ipmmu-vmsa",
+		 ipmmu_vmsa_iommu_of_setup);
+
 MODULE_DESCRIPTION("IOMMU API for Renesas VMSA-compatible IPMMU");
 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
 MODULE_LICENSE("GPL v2");