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From:   Kangjie Lu <kjlu@umn.edu>
To:     kjlu@umn.edu
Cc:     pakki001@umn.edu, Mauro Carvalho Chehab <mchehab@kernel.org>,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] media: stv090x: add missed checks for STV090x_WRITE_DEMOD
Date:   Fri, 22 Mar 2019 21:46:13 -0500
Message-Id: <20190323024614.14883-1-kjlu@umn.edu>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Conservatively check return value of STV090x_WRITE_DEMOD in case
it fails.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
---
 drivers/media/dvb-frontends/stv090x.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/media/dvb-frontends/stv090x.c b/drivers/media/dvb-frontends/stv090x.c
index a0622bb71803..3e2af3969e16 100644
--- a/drivers/media/dvb-frontends/stv090x.c
+++ b/drivers/media/dvb-frontends/stv090x.c
@@ -1446,14 +1446,17 @@ static int stv090x_start_search(struct stv090x_state *state)
 		/* >= Cut 3 */
 		if (state->srate <= 5000000) {
 			/* enlarge the timing bandwidth for Low SR */
-			STV090x_WRITE_DEMOD(state, RTCS2, 0x68);
+			if (STV090x_WRITE_DEMOD(state, RTCS2, 0x68) < 0)
+				goto err;
 		} else {
 			/* reduce timing bandwidth for high SR */
-			STV090x_WRITE_DEMOD(state, RTCS2, 0x44);
+			if (STV090x_WRITE_DEMOD(state, RTCS2, 0x44) < 0)
+				goto err;
 		}
 
 		/* Set CFR min and max to manual mode */
-		STV090x_WRITE_DEMOD(state, CARCFG, 0x46);
+		if (STV090x_WRITE_DEMOD(state, CARCFG, 0x46) < 0)
+			goto err;
 
 		if (state->algo == STV090x_WARM_SEARCH) {
 			/* WARM Start
@@ -2604,7 +2607,8 @@ static enum stv090x_signal_state stv090x_get_sig_params(struct stv090x_state *st
 
 	if (state->algo == STV090x_BLIND_SEARCH) {
 		tmg = STV090x_READ_DEMOD(state, TMGREG2);
-		STV090x_WRITE_DEMOD(state, SFRSTEP, 0x5c);
+		if (STV090x_WRITE_DEMOD(state, SFRSTEP, 0x5c) < 0)
+			goto err;
 		while ((i <= 50) && (tmg != 0) && (tmg != 0xff)) {
 			tmg = STV090x_READ_DEMOD(state, TMGREG2);
 			msleep(5);
@@ -2910,7 +2914,9 @@ static int stv090x_optimize_track(struct stv090x_state *state)
 			pilots = STV090x_GETFIELD_Px(reg, DEMOD_TYPE_FIELD) & 0x01;
 			aclc = stv090x_optimize_carloop(state, modcod, pilots);
 			if (modcod <= STV090x_QPSK_910) {
-				STV090x_WRITE_DEMOD(state, ACLC2S2Q, aclc);
+				if (STV090x_WRITE_DEMOD(state, ACLC2S2Q, aclc)
+						< 0)
+					goto err;
 			} else if (modcod <= STV090x_8PSK_910) {
 				if (STV090x_WRITE_DEMOD(state, ACLC2S2Q, 0x2a) < 0)
 					goto err;
@@ -2972,7 +2978,8 @@ static int stv090x_optimize_track(struct stv090x_state *state)
 	reg = STV090x_READ_DEMOD(state, TMGOBS);
 
 	if (state->algo == STV090x_BLIND_SEARCH) {
-		STV090x_WRITE_DEMOD(state, SFRSTEP, 0x00);
+		if (STV090x_WRITE_DEMOD(state, SFRSTEP, 0x00) < 0)
+			goto err;
 		reg = STV090x_READ_DEMOD(state, DMDCFGMD);
 		STV090x_SETFIELD_Px(reg, SCAN_ENABLE_FIELD, 0x00);
 		STV090x_SETFIELD_Px(reg, CFR_AUTOSCAN_FIELD, 0x00);
-- 
2.17.1