From d47f00e291ae9a54d4b9c3e1f2e930d518b69c7b Mon Sep 17 00:00:00 2001
From: Ian Abbott <abbotti@mev.co.uk>
Date: Tue, 5 Aug 2008 14:43:40 +0000
Subject: [PATCH] Parameters of device_create() changed in 2.6.27-rc1, so call
 compatibility macro COMEDI_DEVICE_CREATE() instead.

---
 comedi/comedi_fops.c   |  4 ++--
 comedi/drivers.c       |  4 ++--
 include/linux/device.h | 38 ++++++++++++++++++++++++++++++++++----
 3 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/comedi/comedi_fops.c b/comedi/comedi_fops.c
index 0568951b..914c9a80 100644
--- a/comedi/comedi_fops.c
+++ b/comedi/comedi_fops.c
@@ -1914,8 +1914,8 @@ static int __init comedi_init(void)
 	for (i = 0; i < COMEDI_NDEVICES; i++) {
 		struct device *csdev;
 		comedi_devices[i].minor = i;
-		csdev = device_create(comedi_class, 0, MKDEV(COMEDI_MAJOR, i),
-				"comedi%i", i);
+		csdev = COMEDI_DEVICE_CREATE(comedi_class, 0,
+				MKDEV(COMEDI_MAJOR, i), NULL, "comedi%i", i);
 		if (!IS_ERR(csdev))
 			comedi_devices[i].class_dev = csdev;
 		spin_lock_init(&comedi_devices[i].spinlock);
diff --git a/comedi/drivers.c b/comedi/drivers.c
index 625c9413..36cbf4b9 100644
--- a/comedi/drivers.c
+++ b/comedi/drivers.c
@@ -291,8 +291,8 @@ static int postconfig(comedi_device * dev)
 			}
 			minor = comedi_construct_minor_for_subdevice(dev, i);
 			devt = MKDEV(COMEDI_MAJOR, minor);
-			csdev = device_create(comedi_class,
-				dev->class_dev, devt, "comedi%i_sub%i",
+			csdev = COMEDI_DEVICE_CREATE(comedi_class,
+				dev->class_dev, devt, NULL, "comedi%i_sub%i",
 				dev->minor, i);
 			if (!IS_ERR(csdev))
 				s->class_dev = csdev;
diff --git a/include/linux/device.h b/include/linux/device.h
index 4ee44548..7ed524df 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -39,6 +39,13 @@
  * The main limitation is that we cannot use a *real* 'struct device *' as
  * the parent parameter of device_create(), only a pointer from a previous
  * call to device_create().
+ *
+ * Call COMEDI_DEVICE_CREATE() instead of device_create() for compatibility
+ * with kernel versions prior to 2.6.27.
+ *
+ * We do not currently support 'dev_get_drvdata()' and 'dev_set_drvdata()'
+ * for kernel versions prior to 2.6.26, so the 'drvdata' parameter of
+ * COMEDI_DEVICE_CREATE() is pretty useless.
  */
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,5,0)
@@ -61,7 +68,7 @@ static inline void class_destroy(struct class *cs)
 }
 
 static inline struct device *device_create(struct class *cls,
-	struct device *parent, dev_t devt, char *fmt, ...)
+	struct device *parent, dev_t devt, void *drvdata, char *fmt, ...)
 {
 	return NULL;
 }
@@ -80,7 +87,7 @@ static inline void device_destroy(struct class *cs, dev_t devt)
 	(struct class *)class_simple_create(owner, name)
 #define class_destroy(cs) \
 	class_simple_destroy((struct class_simple *)(cs))
-#define device_create(cs, parent, devt, fmt...) \
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
 	(struct device *)class_simple_device_add((struct class_simple *)(cs), \
 		devt, NULL, fmt)
 #define device_destroy(cs, devt) \
@@ -90,7 +97,7 @@ static inline void device_destroy(struct class *cs, dev_t devt)
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,15)
 
-#define device_create(cs, parent, devt, fmt...) \
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
 	(struct device *)class_device_create(cs, devt, NULL, fmt)
 #define device_destroy(cs, devt) \
 	class_device_destroy(cs, devt)
@@ -99,12 +106,35 @@ static inline void device_destroy(struct class *cs, dev_t devt)
 
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,18)
 
-#define device_create(cs, parent, devt, fmt...) \
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
 	(struct device *)class_device_create( \
 			cs, (struct class_device *)parent, devt, NULL, fmt)
 #define device_destroy(cs, devt) \
 	class_device_destroy(cs, devt)
 
+#else
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,26)
+
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
+	device_create(cs, parent, devt, fmt)
+
+#else
+
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27)
+
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
+	device_create_drvdata(cs, parent, devt, drvdata, fmt)
+
+#else
+
+#define COMEDI_DEVICE_CREATE(cs, parent, devt, drvdata, fmt...) \
+	device_create(cs, parent, devt, drvdata, fmt)
+
+#endif // LINUX_VERSION_CODE < KERNEL_VERSION(2,6,27)
+
+#endif // LINUX_VERSION_CODE < KERNEL_VERSION(2,6,26)
+
 #endif // LINUX_VERSION_CODE < KERNEL_VERSION(2,6,18)
 
 #endif // LINUX_VERSION_CODE < KERNEL_VERSION(2,6,15)
-- 
2.26.2