of/i2c: Generalize OF support

This patch cleans up the i2c OF support code to make it selectable by
all architectures and allow for automatic registration of i2c devices.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

2 files changed, 30 insertions, 22 deletions

diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index 097f42aebe90..80dd6318db68 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -26,7 +26,7 @@ config OF_GPIO
 
 config OF_I2C
 	def_tristate I2C
-	depends on (PPC_OF || MICROBLAZE) && I2C
+	depends on OF && !SPARC && I2C
 	help
 	  OpenFirmware I2C accessors
 
diff --git a/drivers/of/of_i2c.c b/drivers/of/of_i2c.c
index ab6522c8e4fe..0a694debd226 100644
--- a/drivers/of/of_i2c.c
+++ b/drivers/of/of_i2c.c
@@ -14,57 +14,65 @@
 #include <linux/i2c.h>
 #include <linux/of.h>
 #include <linux/of_i2c.h>
+#include <linux/of_irq.h>
 #include <linux/module.h>
 
-void of_register_i2c_devices(struct i2c_adapter *adap,
-			     struct device_node *adap_node)
+void of_i2c_register_devices(struct i2c_adapter *adap)
 {
 	void *result;
 	struct device_node *node;
 
-	for_each_child_of_node(adap_node, node) {
+	/* Only register child devices if the adapter has a node pointer set */
+	if (!adap->dev.of_node)
+		return;
+
+	dev_dbg(&adap->dev, "of_i2c: walking child nodes\n");
+
+	for_each_child_of_node(adap->dev.of_node, node) {
 		struct i2c_board_info info = {};
 		struct dev_archdata dev_ad = {};
 		const __be32 *addr;
 		int len;
 
-		if (of_modalias_node(node, info.type, sizeof(info.type)) < 0)
+		dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name);
+
+		if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) {
+			dev_err(&adap->dev, "of_i2c: modalias failure on %s\n",
+				node->full_name);
 			continue;
+		}
 
 		addr = of_get_property(node, "reg", &len);
-		if (!addr || len < sizeof(int) || *addr > (1 << 10) - 1) {
-			printk(KERN_ERR
-			       "of-i2c: invalid i2c device entry\n");
+		if (!addr || (len < sizeof(int))) {
+			dev_err(&adap->dev, "of_i2c: invalid reg on %s\n",
+				node->full_name);
 			continue;
 		}
 
-		info.irq = irq_of_parse_and_map(node, 0);
-
 		info.addr = be32_to_cpup(addr);
+		if (info.addr > (1 << 10) - 1) {
+			dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n",
+				info.addr, node->full_name);
+			continue;
+		}
 
-		info.of_node = node;
+		info.irq = irq_of_parse_and_map(node, 0);
+		info.of_node = of_node_get(node);
 		info.archdata = &dev_ad;
 
 		request_module("%s", info.type);
 
 		result = i2c_new_device(adap, &info);
 		if (result == NULL) {
-			printk(KERN_ERR
-			       "of-i2c: Failed to load driver for %s\n",
-			       info.type);
+			dev_err(&adap->dev, "of_i2c: Failure registering %s\n",
+			        node->full_name);
+			of_node_put(node);
 			irq_dispose_mapping(info.irq);
 			continue;
 		}
-
-		/*
-		 * Get the node to not lose the dev_archdata->of_node.
-		 * Currently there is no way to put it back, as well as no
-		 * of_unregister_i2c_devices() call.
-		 */
-		of_node_get(node);
 	}
 }
-EXPORT_SYMBOL(of_register_i2c_devices);
+EXPORT_SYMBOL(of_i2c_register_devices);
 
 static int of_dev_node_match(struct device *dev, void *data)
 {