drm/bridge: tc358767: Simplify polling in tc_link_training()

Replace explicit polling in tc_link_training() with equivalent call to
tc_poll_timeout() for simplicity. No functional change intended (not
including slightly altered debug output).
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190619052716.16831-4-andrew.smirnov@gmail.com

drivers/gpu/drm/bridge/tc358767.c

@@ -739,22 +739,19 @@ static int tc_set_video_mode(struct tc_data *tc,
 
 static int tc_wait_link_training(struct tc_data *tc)
 {
-	u32 timeout = 1000;
 	u32 value;
 	int ret;
 
-	do {
-		udelay(1);
-		tc_read(DP0_LTSTAT, &value);
-	} while ((!(value & LT_LOOPDONE)) && (--timeout));
-
-	if (timeout == 0) {
+	ret = tc_poll_timeout(tc, DP0_LTSTAT, LT_LOOPDONE,
+			      LT_LOOPDONE, 1, 1000);
+	if (ret) {
 		dev_err(tc->dev, "Link training timeout waiting for LT_LOOPDONE!\n");
-		return -ETIMEDOUT;
+		return ret;
 	}
 
-	return (value >> 8) & 0x7;
+	tc_read(DP0_LTSTAT, &value);
 
+	return (value >> 8) & 0x7;
 err:
 	return ret;
 }