iwlwifi: correct return code for log_event

When dumping event log in debugfs, iwl_dump_nic_event_log()
should return the correct error code instead of let the calling
function makes it own assumption.
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-agn.c

@@ -1965,7 +1965,7 @@ int iwl_dump_nic_event_log(struct iwl_priv *priv, bool full_log,
 		IWL_ERR(priv,
 			"Invalid event log pointer 0x%08X for %s uCode\n",
 			base, (priv->ucode_type == UCODE_INIT) ? "Init" : "RT");
-		return pos;
+		return -EINVAL;
 	}
 
 	/* event log header */
@@ -2013,7 +2013,7 @@ int iwl_dump_nic_event_log(struct iwl_priv *priv, bool full_log,
 			bufsz = size * 48;
 		*buf = kmalloc(bufsz, GFP_KERNEL);
 		if (!*buf)
-			return pos;
+			return -ENOMEM;
 	}
 	if ((iwl_get_debug_level(priv) & IWL_DL_FW_ERRORS) || full_log) {
 		/*

drivers/net/wireless/iwlwifi/iwl-debugfs.c

@@ -429,8 +429,9 @@ static ssize_t iwl_dbgfs_log_event_read(struct file *file,
 	int pos = 0;
 	ssize_t ret = -ENOMEM;
 
-	pos = priv->cfg->ops->lib->dump_nic_event_log(priv, true, &buf, true);
-	if (pos && buf) {
+	ret = pos = priv->cfg->ops->lib->dump_nic_event_log(
+					priv, true, &buf, true);
+	if (buf) {
 		ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 		kfree(buf);
 	}

drivers/net/wireless/iwlwifi/iwl3945-base.c

@@ -1644,7 +1644,7 @@ int iwl3945_dump_nic_event_log(struct iwl_priv *priv, bool full_log,
 	base = le32_to_cpu(priv->card_alive.log_event_table_ptr);
 	if (!iwl3945_hw_valid_rtc_data_addr(base)) {
 		IWL_ERR(priv, "Invalid event log pointer 0x%08X\n", base);
-		return pos;
+		return  -EINVAL;
 	}
 
 	/* event log header */
@@ -1693,7 +1693,7 @@ int iwl3945_dump_nic_event_log(struct iwl_priv *priv, bool full_log,
 			bufsz = size * 48;
 		*buf = kmalloc(bufsz, GFP_KERNEL);
 		if (!*buf)
-			return pos;
+			return -ENOMEM;
 	}
 	if ((iwl_get_debug_level(priv) & IWL_DL_FW_ERRORS) || full_log) {
 		/* if uCode has wrapped back to top of log,