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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 7c27a8ebef6..3cbc57f932d 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);