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authorLinus Torvalds <torvalds@linux-foundation.org>2009-09-11 09:19:35 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-11 09:19:35 -0700
commita9c86d42599519f3d83b5f46bdab25046fe47b84 (patch)
tree9b269e3162e5cc0c1a8dfc3349303c902718a9a9 /fs/char_dev.c
parenta12e4d304ce701844c639541d90df86e165d03f9 (diff)
parent1110afbe728838ac7ce973c37af9e11385dbaef9 (diff)
downloadlinux-a9c86d42599519f3d83b5f46bdab25046fe47b84.tar.gz
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6: (377 commits)
  ASoC: au1x: PSC-AC97 bugfixes
  ALSA: dummy - Increase MAX_PCM_SUBSTREAMS to 128
  ALSA: dummy - Add debug proc file
  ALSA: Add const prefix to proc helper functions
  ALSA: Re-export snd_pcm_format_name() function
  ALSA: hda - Use auto model for HP laptops with ALC268 codec
  ALSA: cs46xx - Fix minimum period size
  ASoC: Fix WM835x Out4 capture enumeration
  ALSA: Remove unneeded ifdef from sound/core.h
  ALSA: Remove struct snd_monitor_file from public sound/core.h
  ASoC: Remove unuused hw_read_t
  sound: oxygen: work around MCE when changing volume
  ALSA: dummy - Fake buffer allocations
  ALSA: hda/realtek: Added support for CLEVO M540R subsystem, 6 channel + digital
  ASoC: fix pxa2xx-ac97.c breakage
  ALSA: dummy - Fix the timer calculation in systimer mode
  ALSA: dummy - Add more description
  ALSA: dummy - Better jiffies handling
  ALSA: dummy - Support high-res timer mode
  ALSA: Release v1.0.21
  ...
Diffstat (limited to 'fs/char_dev.c')
-rw-r--r--fs/char_dev.c39
1 files changed, 26 insertions, 13 deletions
diff --git a/fs/char_dev.c b/fs/char_dev.c
index 7c27a8ebef6a..3cbc57f932d2 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -238,8 +238,10 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
 }
 
 /**
- * register_chrdev() - Register a major number for character devices.
+ * __register_chrdev() - create and register a cdev occupying a range of minors
  * @major: major device number or 0 for dynamic allocation
+ * @baseminor: first of the requested range of minor numbers
+ * @count: the number of minor numbers required
  * @name: name of this range of devices
  * @fops: file operations associated with this devices
  *
@@ -255,19 +257,17 @@ int alloc_chrdev_region(dev_t *dev, unsigned baseminor, unsigned count,
  * /dev. It only helps to keep track of the different owners of devices. If
  * your module name has only one type of devices it's ok to use e.g. the name
  * of the module here.
- *
- * This function registers a range of 256 minor numbers. The first minor number
- * is 0.
  */
-int register_chrdev(unsigned int major, const char *name,
-		    const struct file_operations *fops)
+int __register_chrdev(unsigned int major, unsigned int baseminor,
+		      unsigned int count, const char *name,
+		      const struct file_operations *fops)
 {
 	struct char_device_struct *cd;
 	struct cdev *cdev;
 	char *s;
 	int err = -ENOMEM;
 
-	cd = __register_chrdev_region(major, 0, 256, name);
+	cd = __register_chrdev_region(major, baseminor, count, name);
 	if (IS_ERR(cd))
 		return PTR_ERR(cd);
 	
@@ -281,7 +281,7 @@ int register_chrdev(unsigned int major, const char *name,
 	for (s = strchr(kobject_name(&cdev->kobj),'/'); s; s = strchr(s, '/'))
 		*s = '!';
 		
-	err = cdev_add(cdev, MKDEV(cd->major, 0), 256);
+	err = cdev_add(cdev, MKDEV(cd->major, baseminor), count);
 	if (err)
 		goto out;
 
@@ -291,7 +291,7 @@ int register_chrdev(unsigned int major, const char *name,
 out:
 	kobject_put(&cdev->kobj);
 out2:
-	kfree(__unregister_chrdev_region(cd->major, 0, 256));
+	kfree(__unregister_chrdev_region(cd->major, baseminor, count));
 	return err;
 }
 
@@ -317,10 +317,23 @@ void unregister_chrdev_region(dev_t from, unsigned count)
 	}
 }
 
-void unregister_chrdev(unsigned int major, const char *name)
+/**
+ * __unregister_chrdev - unregister and destroy a cdev
+ * @major: major device number
+ * @baseminor: first of the range of minor numbers
+ * @count: the number of minor numbers this cdev is occupying
+ * @name: name of this range of devices
+ *
+ * Unregister and destroy the cdev occupying the region described by
+ * @major, @baseminor and @count.  This function undoes what
+ * __register_chrdev() did.
+ */
+void __unregister_chrdev(unsigned int major, unsigned int baseminor,
+			 unsigned int count, const char *name)
 {
 	struct char_device_struct *cd;
-	cd = __unregister_chrdev_region(major, 0, 256);
+
+	cd = __unregister_chrdev_region(major, baseminor, count);
 	if (cd && cd->cdev)
 		cdev_del(cd->cdev);
 	kfree(cd);
@@ -569,6 +582,6 @@ EXPORT_SYMBOL(cdev_alloc);
 EXPORT_SYMBOL(cdev_del);
 EXPORT_SYMBOL(cdev_add);
 EXPORT_SYMBOL(cdev_index);
-EXPORT_SYMBOL(register_chrdev);
-EXPORT_SYMBOL(unregister_chrdev);
+EXPORT_SYMBOL(__register_chrdev);
+EXPORT_SYMBOL(__unregister_chrdev);
 EXPORT_SYMBOL(directly_mappable_cdev_bdi);