i2c: Convert i2c-octeon.c to use device tree.

There are three parts to this:

1) Remove the definitions of OCTEON_IRQ_TWSI and OCTEON_IRQ_TWSI2.
   The interrupts are specified by the device tree and these hard
   coded irq numbers block the used of the irq lines by the irq_domain
   code.

2) Remove platform device setup code from octeon-platform.c, it is
   now unused.

3) Convert i2c-octeon.c to use device tree.  Part of this includes
   using the devm_* functions instead of the raw counterparts, thus
   simplifying error handling.  No functionality is changed.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: linux-mips@linux-mips.org
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/3939/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 49 insertions, 43 deletions

diff --git a/drivers/i2c/busses/i2c-octeon.c b/drivers/i2c/busses/i2c-octeon.c
index ee139a598814..f44c83549fe5 100644
--- a/drivers/i2c/busses/i2c-octeon.c
+++ b/drivers/i2c/busses/i2c-octeon.c
@@ -2,7 +2,7 @@
  * (C) Copyright 2009-2010
  * Nokia Siemens Networks, michael.lawnick.ext@nsn.com
  *
- * Portions Copyright (C) 2010 Cavium Networks, Inc.
+ * Portions Copyright (C) 2010, 2011 Cavium Networks, Inc.
  *
  * This is a driver for the i2c adapter in Cavium Networks' OCTEON processors.
  *
@@ -11,17 +11,18 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of_i2c.h>
+#include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/init.h>
-
-#include <linux/io.h>
 #include <linux/i2c.h>
-#include <linux/interrupt.h>
-#include <linux/delay.h>
-#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/of.h>
 
 #include <asm/octeon/octeon.h>
 
@@ -65,7 +66,7 @@ struct octeon_i2c {
         wait_queue_head_t queue;
         struct i2c_adapter adap;
         int irq;
-        int twsi_freq;
+        u32 twsi_freq;
         int sys_freq;
         resource_size_t twsi_phys;
         void __iomem *twsi_base;
@@ -121,10 +122,8 @@ static u8 octeon_i2c_read_sw(struct octeon_i2c *i2c, u64 eop_reg)
  */
 static void octeon_i2c_write_int(struct octeon_i2c *i2c, u64 data)
 {
-        u64 tmp;
-
         __raw_writeq(data, i2c->twsi_base + TWSI_INT);
-        tmp = __raw_readq(i2c->twsi_base + TWSI_INT);
+        __raw_readq(i2c->twsi_base + TWSI_INT);
 }
 
 /**
@@ -515,7 +514,6 @@ static int __devinit octeon_i2c_probe(struct platform_device *pdev)
 {
         int irq, result = 0;
         struct octeon_i2c *i2c;
-        struct octeon_i2c_data *i2c_data;
         struct resource *res_mem;
 
         /* All adaptors have an irq.  */
@@ -523,86 +521,90 @@ static int __devinit octeon_i2c_probe(struct platform_device *pdev)
         if (irq < 0)
                 return irq;
 
-        i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
+        i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
         if (!i2c) {
                 dev_err(&pdev->dev, "kzalloc failed\n");
                 result = -ENOMEM;
                 goto out;
         }
         i2c->dev = &pdev->dev;
-        i2c_data = pdev->dev.platform_data;
 
         res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 
         if (res_mem == NULL) {
                 dev_err(i2c->dev, "found no memory resource\n");
                 result = -ENXIO;
-                goto fail_region;
+                goto out;
         }
+        i2c->twsi_phys = res_mem->start;
+        i2c->regsize = resource_size(res_mem);
 
-        if (i2c_data == NULL) {
-                dev_err(i2c->dev, "no I2C frequency data\n");
+        /*
+         * "clock-rate" is a legacy binding, the official binding is
+         * "clock-frequency".  Try the official one first and then
+         * fall back if it doesn't exist.
+         */
+        if (of_property_read_u32(pdev->dev.of_node,
+                                 "clock-frequency", &i2c->twsi_freq) &&
+            of_property_read_u32(pdev->dev.of_node,
+                                 "clock-rate", &i2c->twsi_freq)) {
+                dev_err(i2c->dev,
+                        "no I2C 'clock-rate' or 'clock-frequency' property\n");
                 result = -ENXIO;
-                goto fail_region;
+                goto out;
         }
 
-        i2c->twsi_phys = res_mem->start;
-        i2c->regsize = resource_size(res_mem);
-        i2c->twsi_freq = i2c_data->i2c_freq;
-        i2c->sys_freq = i2c_data->sys_freq;
+        i2c->sys_freq = octeon_get_io_clock_rate();
 
-        if (!request_mem_region(i2c->twsi_phys, i2c->regsize, res_mem->name)) {
+        if (!devm_request_mem_region(&pdev->dev, i2c->twsi_phys, i2c->regsize,
+                                      res_mem->name)) {
                 dev_err(i2c->dev, "request_mem_region failed\n");
-                goto fail_region;
+                goto out;
         }
-        i2c->twsi_base = ioremap(i2c->twsi_phys, i2c->regsize);
+        i2c->twsi_base = devm_ioremap(&pdev->dev, i2c->twsi_phys, i2c->regsize);
 
         init_waitqueue_head(&i2c->queue);
 
         i2c->irq = irq;
 
-        result = request_irq(i2c->irq, octeon_i2c_isr, 0, DRV_NAME, i2c);
+        result = devm_request_irq(&pdev->dev, i2c->irq,
+                                  octeon_i2c_isr, 0, DRV_NAME, i2c);
         if (result < 0) {
                 dev_err(i2c->dev, "failed to attach interrupt\n");
-                goto fail_irq;
+                goto out;
         }
 
         result = octeon_i2c_initlowlevel(i2c);
         if (result) {
                 dev_err(i2c->dev, "init low level failed\n");
-                goto  fail_add;
+                goto  out;
         }
 
         result = octeon_i2c_setclock(i2c);
         if (result) {
                 dev_err(i2c->dev, "clock init failed\n");
-                goto  fail_add;
+                goto  out;
         }
 
         i2c->adap = octeon_i2c_ops;
         i2c->adap.dev.parent = &pdev->dev;
-        i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
+        i2c->adap.dev.of_node = pdev->dev.of_node;
         i2c_set_adapdata(&i2c->adap, i2c);
         platform_set_drvdata(pdev, i2c);
 
-        result = i2c_add_numbered_adapter(&i2c->adap);
+        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, "version %s\n", DRV_VERSION);
 
-        return result;
+        of_i2c_register_devices(&i2c->adap);
+
+        return 0;
 
 fail_add:
         platform_set_drvdata(pdev, NULL);
-        free_irq(i2c->irq, i2c);
-fail_irq:
-        iounmap(i2c->twsi_base);
-        release_mem_region(i2c->twsi_phys, i2c->regsize);
-fail_region:
-        kfree(i2c);
 out:
         return result;
 };
@@ -613,19 +615,24 @@ static int __devexit octeon_i2c_remove(struct platform_device *pdev)
 
         i2c_del_adapter(&i2c->adap);
         platform_set_drvdata(pdev, NULL);
-        free_irq(i2c->irq, i2c);
-        iounmap(i2c->twsi_base);
-        release_mem_region(i2c->twsi_phys, i2c->regsize);
-        kfree(i2c);
         return 0;
 };
 
+static struct of_device_id octeon_i2c_match[] = {
+        {
+                .compatible = "cavium,octeon-3860-twsi",
+        },
+        {},
+};
+MODULE_DEVICE_TABLE(of, octeon_i2c_match);
+
 static struct platform_driver octeon_i2c_driver = {
         .probe          = octeon_i2c_probe,
         .remove         = __devexit_p(octeon_i2c_remove),
         .driver         = {
                 .owner  = THIS_MODULE,
                 .name   = DRV_NAME,
+                .of_match_table = octeon_i2c_match,
         },
 };
 
@@ -635,4 +642,3 @@ MODULE_AUTHOR("Michael Lawnick <michael.lawnick.ext@nsn.com>");
 MODULE_DESCRIPTION("I2C-Bus adapter for Cavium OCTEON processors");
 MODULE_LICENSE("GPL");
 MODULE_VERSION(DRV_VERSION);
-MODULE_ALIAS("platform:" DRV_NAME);