isdn: use simple_read_from_buffer()

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 8 insertions, 21 deletions

diff --git a/drivers/isdn/hysdn/hysdn_procconf.c b/drivers/isdn/hysdn/hysdn_procconf.c
index 15906d005b05..484299b031f8 100644
--- a/drivers/isdn/hysdn/hysdn_procconf.c
+++ b/drivers/isdn/hysdn/hysdn_procconf.c
@@ -207,30 +207,17 @@ hysdn_conf_write(struct file *file, const char __user *buf, size_t count, loff_t
 /* read conf file -> output card info data */
 /*******************************************/
 static ssize_t
-hysdn_conf_read(struct file *file, char __user *buf, size_t count, loff_t * off)
+hysdn_conf_read(struct file *file, char __user *buf, size_t count, loff_t *off)
 {
         char *cp;
-        int i;
 
-        if (file->f_mode & FMODE_READ) {
-                if (!(cp = file->private_data))
-                        return (-EFAULT);       /* should never happen */
-                i = strlen(cp); /* get total string length */
-                if (*off < i) {
-                        /* still bytes to transfer */
-                        cp += *off;     /* point to desired data offset */
-                        i -= *off;      /* remaining length */
-                        if (i > count)
-                                i = count;      /* limit length to transfer */
-                        if (copy_to_user(buf, cp, i))
-                                return (-EFAULT);       /* copy error */
-                        *off += i;      /* adjust offset */
-                } else
-                        return (0);
-        } else
-                return (-EPERM);        /* no permission to read */
-
-        return (i);
+        if (!(file->f_mode & FMODE_READ))
+                return -EPERM;  /* no permission to read */
+
+        if (!(cp = file->private_data))
+                return -EFAULT; /* should never happen */
+
+        return simple_read_from_buffer(buf, count, off, cp, strlen(cp));
 }                               /* hysdn_conf_read */
 
 /******************/