staging: r8188eu: simplify c2h_evt_hdl function

Simplify c2h_evt_hdl function by removing majority of its code. The
function always returned _FAIL anyway, due to the wrapper function it
calls always returning _FAIL, and its one caller doesn't use the return
value, so this function should just have a return type of void.

Leave the call to c2h_evt_read in place, as without it, event handling
semantics of the driver would be changed, despite nothing actually being
done with the event.
Acked-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Acked-by: Michael Straube <straube.linux@gmail.com>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://lore.kernel.org/r/20210829234541.946-3-phil@philpotter.co.ukSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/core/rtw_cmd.c

@@ -1852,29 +1852,12 @@ u8 rtw_c2h_wk_cmd(struct adapter *padapter, u8 *c2h_evt)
 	return res;
 }
 
-static s32 c2h_evt_hdl(struct adapter *adapter, struct c2h_evt_hdr *c2h_evt, c2h_id_filter filter)
+static void c2h_evt_hdl(struct adapter *adapter, struct c2h_evt_hdr *c2h_evt, c2h_id_filter filter)
 {
-	s32 ret = _FAIL;
 	u8 buf[16];
 
-	if (!c2h_evt) {
-		/* No c2h event in cmd_obj, read c2h event before handling*/
-		if (c2h_evt_read(adapter, buf) == _SUCCESS) {
-			c2h_evt = (struct c2h_evt_hdr *)buf;
-
-			if (filter && !filter(c2h_evt->id))
-				goto exit;
-
-			ret = rtw_hal_c2h_handler(adapter, c2h_evt);
-		}
-	} else {
-		if (filter && !filter(c2h_evt->id))
-			goto exit;
-
-		ret = rtw_hal_c2h_handler(adapter, c2h_evt);
-	}
-exit:
-	return ret;
+	if (!c2h_evt)
+		c2h_evt_read(adapter, buf);
 }
 
 static void c2h_wk_callback(struct work_struct *work)