{
        struct ath9k_htc_priv *priv = file->private_data;
        char buf[512];
-       unsigned int len = 0;
+       unsigned int len;
 
        spin_lock_bh(&priv->tx.tx_lock);
-
-       len += scnprintf(buf + len, sizeof(buf) - len, "TX slot bitmap : ");
-
-       len += bitmap_scnprintf(buf + len, sizeof(buf) - len,
-                              priv->tx.tx_slot, MAX_TX_BUF_NUM);
-
-       len += scnprintf(buf + len, sizeof(buf) - len, "\n");
-
-       len += scnprintf(buf + len, sizeof(buf) - len,
-                        "Used slots     : %d\n",
-                        bitmap_weight(priv->tx.tx_slot, MAX_TX_BUF_NUM));
-
+       len = scnprintf(buf, sizeof(buf),
+                       "TX slot bitmap : %*pb\n"
+                       "Used slots     : %d\n",
+                       MAX_TX_BUF_NUM, priv->tx.tx_slot,
+                       bitmap_weight(priv->tx.tx_slot, MAX_TX_BUF_NUM));
        spin_unlock_bh(&priv->tx.tx_lock);
-
-       if (len > sizeof(buf))
-               len = sizeof(buf);
-
        return simple_read_from_buffer(user_buf, count, ppos, buf, len);
 }
 
 
 static char *carl9170_debugfs_mem_usage_read(struct ar9170 *ar, char *buf,
                                             size_t bufsize, ssize_t *len)
 {
-       ADD(buf, *len, bufsize, "jar: [");
-
        spin_lock_bh(&ar->mem_lock);
 
-       *len += bitmap_scnprintf(&buf[*len], bufsize - *len,
-                                 ar->mem_bitmap, ar->fw.mem_blocks);
-
-       ADD(buf, *len, bufsize, "]\n");
+       ADD(buf, *len, bufsize, "jar: [%*pb]\n",
+           ar->fw.mem_blocks, ar->mem_bitmap);
 
        ADD(buf, *len, bufsize, "cookies: used:%3d / total:%3d, allocs:%d\n",
            bitmap_weight(ar->mem_bitmap, ar->fw.mem_blocks),
                    cnt, iter->tid, iter->bsn, iter->snx, iter->hsn,
                    iter->max, iter->state, iter->counter);
 
-               ADD(buf, *len, bufsize, "\tWindow:  [");
-
-               *len += bitmap_scnprintf(&buf[*len], bufsize - *len,
-                       iter->bitmap, CARL9170_BAW_BITS);
+               ADD(buf, *len, bufsize, "\tWindow:  [%*pb,W]\n",
+                   CARL9170_BAW_BITS, iter->bitmap);
 
 #define BM_STR_OFF(offset)                                     \
        ((CARL9170_BAW_BITS - (offset) - 1) / 4 +               \
         (CARL9170_BAW_BITS - (offset) - 1) / 32 + 1)
 
-               ADD(buf, *len, bufsize, ",W]\n");
-
                offset = BM_STR_OFF(0);
                ADD(buf, *len, bufsize, "\tBase Seq: %*s\n", offset, "T");
 
        ADD(buf, *len, bufsize, "registered VIFs:%d \\ %d\n",
            ar->vifs, ar->fw.vif_num);
 
-       ADD(buf, *len, bufsize, "VIF bitmap: [");
-
-       *len += bitmap_scnprintf(&buf[*len], bufsize - *len,
-                                &ar->vif_bitmap, ar->fw.vif_num);
-
-       ADD(buf, *len, bufsize, "]\n");
+       ADD(buf, *len, bufsize, "VIF bitmap: [%*pb]\n",
+           ar->fw.vif_num, &ar->vif_bitmap);
 
        rcu_read_lock();
        list_for_each_entry_rcu(iter, &ar->vif_list, list) {