[PATCH] i2c: xiic: Add OF support for Xilinx i2c bus interface

[Michal Simek]

Add OF support to Xilinx i2c bus interface.
It is used on Microblaze systems.

Signed-off-by: Michal Simek <monstr at monstr.eu>
---
 drivers/i2c/busses/i2c-xiic.c |  111 ++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index a9c419e..22951a3 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -2,6 +2,8 @@
  * i2c-xiic.c
  * Copyright (c) 2002-2007 Xilinx Inc.
  * Copyright (c) 2009-2010 Intel Corporation
+ * Copyright (c) 2010-2011 Michal Simek <monstr at monstr.eu>
+ * Copyright (c) 2010-2011 PetaLogix
  *
  * 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
@@ -41,6 +43,13 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 
+#ifdef CONFIG_OF
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_i2c.h>
+#include <linux/of_address.h>
+#endif
+
 #define DRIVER_NAME "xiic-i2c"
 
 enum xilinx_i2c_state {
@@ -426,7 +435,7 @@ static void xiic_process(struct xiic_i2c *i2c)
 			xiic_wakeup(i2c, STATE_ERROR);
 
 	} else if (pend & (XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK)) {
-		/* Transmit register/FIFO is empty or ½ empty */
+		/* Transmit register/FIFO is empty or 1/2 empty */
 
 		clr = pend &
 			(XIIC_INTR_TX_EMPTY_MASK | XIIC_INTR_TX_HALF_MASK);
@@ -687,7 +696,7 @@ static struct i2c_adapter xiic_adapter = {
 	.algo		= &xiic_algorithm,
 };
 
-
+#ifndef CONFIG_OF
 static int __devinit xiic_i2c_probe(struct platform_device *pdev)
 {
 	struct xiic_i2c *i2c;
@@ -808,6 +817,104 @@ static struct platform_driver xiic_i2c_driver = {
 	},
 };
 
+#else
+static int __devinit xiic_i2c_of_probe(struct platform_device *op)
+{
+	struct xiic_i2c *i2c;
+	int result = 0;
+
+	i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	i2c->dev = &op->dev; /* for debug and error output */
+
+	spin_lock_init(&i2c->lock);
+	init_waitqueue_head(&i2c->wait);
+
+	i2c->base = of_iomap(op->dev.of_node, 0);
+	if (!i2c->base) {
+		dev_err(i2c->dev, "failed to map controller\n");
+		result = -ENOMEM;
+		goto fail_map;
+	}
+
+	i2c->irq = irq_of_parse_and_map(op->dev.of_node, 0);
+	if (i2c->irq) { /* no i2c->irq implies polling */
+		result = request_irq(i2c->irq, xiic_isr,
+				     0, op->name, i2c);
+		if (result < 0) {
+			dev_err(i2c->dev, "failed to attach interrupt\n");
+			goto fail_request;
+		}
+	}
+
+	dev_set_drvdata(&op->dev, i2c);
+	i2c->adap = xiic_adapter;
+	i2c_set_adapdata(&i2c->adap, i2c);
+	i2c->adap.dev.parent = &op->dev;
+	i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
+
+	result = i2c_add_adapter(&i2c->adap);
+	if (result < 0) {
+		dev_err(i2c->dev, "failed to add adapter\n");
+		goto fail_add;
+	}
+
+	dev_info(i2c->dev, "mapped to 0x%08X, irq=%d\n",
+					(unsigned int)i2c->base, i2c->irq);
+
+	xiic_reinit(i2c);
+	of_i2c_register_devices(&i2c->adap);
+
+	return result;
+
+fail_add:
+	dev_set_drvdata(&op->dev, NULL);
+	free_irq(i2c->irq, i2c);
+fail_request:
+	irq_dispose_mapping(i2c->irq);
+	iounmap(i2c->base);
+fail_map:
+	kfree(i2c);
+	return result;
+}
+
+static int __devexit xiic_i2c_of_remove(struct platform_device *op)
+{
+	struct xiic_i2c *i2c = dev_get_drvdata(&op->dev);
+
+	i2c_del_adapter(&i2c->adap);
+	xiic_deinit(i2c);
+	dev_set_drvdata(&op->dev, NULL);
+
+	if (i2c->irq)
+		free_irq(i2c->irq, i2c);
+
+	irq_dispose_mapping(i2c->irq);
+	iounmap(i2c->base);
+	kfree(i2c);
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static struct of_device_id __devinitdata xilinx_iic_of_match[] = {
+	{ .compatible = "xlnx,xps-iic-2.00.a", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, xilinx_iic_of_match);
+
+static struct platform_driver xiic_i2c_driver = {
+	.probe   = xiic_i2c_of_probe,
+	.remove  = __devexit_p(xiic_i2c_of_remove),
+	.driver  = {
+		.owner = THIS_MODULE,
+		.name = DRIVER_NAME,
+		.of_match_table = xilinx_iic_of_match,
+	},
+};
+#endif
+
 static int __init xiic_i2c_init(void)
 {
 	return platform_driver_register(&xiic_i2c_driver);
-- 
1.5.5.6