Rationalize fasync return values

Most fasync implementations do something like:

     return fasync_helper(...);

But fasync_helper() will return a positive value at times - a feature used
in at least one place.  Thus, a number of other drivers do:

     err = fasync_helper(...);
     if (err < 0)
             return err;
     return 0;

In the interests of consistency and more concise code, it makes sense to
map positive return values onto zero where ->fasync() is called.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

3 files changed, 4 insertions, 13 deletions

diff --git a/sound/core/control.c b/sound/core/control.c
index 636b3b52ef8b..4b20fa2b7e6d 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -1373,12 +1373,9 @@ EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat);
 static int snd_ctl_fasync(int fd, struct file * file, int on)
 {
         struct snd_ctl_file *ctl;
-        int err;
+
         ctl = file->private_data;
-        err = fasync_helper(fd, file, on, &ctl->fasync);
-        if (err < 0)
-                return err;
-        return 0;
+        return fasync_helper(fd, file, on, &ctl->fasync);
 }
 
 /*
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index a789efc9df39..a75c194e629e 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -3246,9 +3246,7 @@ static int snd_pcm_fasync(int fd, struct file * file, int on)
         err = fasync_helper(fd, file, on, &runtime->fasync);
 out:
         unlock_kernel();
-        if (err < 0)
-                return err;
-        return 0;
+        return err;
 }
 
 /*
diff --git a/sound/core/timer.c b/sound/core/timer.c
index 796532081e81..3f0050d0b71e 100644
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -1825,13 +1825,9 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
 static int snd_timer_user_fasync(int fd, struct file * file, int on)
 {
         struct snd_timer_user *tu;
-        int err;
 
         tu = file->private_data;
-        err = fasync_helper(fd, file, on, &tu->fasync);
-        if (err < 0)
-                return err;
-        return 0;
+        return fasync_helper(fd, file, on, &tu->fasync);
 }
 
 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,