[PATCH 1/2] media: dvb-usb-v2: lmedm04: move ts2020 attach to dm04_lme2510_tuner

[Paolo Pisati]

From: Malcolm Priestley <tvboxspy at gmail.com>

When the tuner was split from m88rs2000 the attach function is in wrong
place.

Move to dm04_lme2510_tuner to trap errors on failure and removing
a call to lme_coldreset.

Prevents driver starting up without any tuner connected.

Fixes to trap for ts2020 fail.
LME2510(C): FE Found M88RS2000
ts2020: probe of 0-0060 failed with error -11
...
LME2510(C): TUN Found RS2000 tuner
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN

Reported-by: Andrey Konovalov <andreyknvl at google.com>
Signed-off-by: Malcolm Priestley <tvboxspy at gmail.com>
Tested-by: Andrey Konovalov <andreyknvl at google.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab at s-opensource.com>
(cherry picked from commit 7bf7a7116ed313c601307f7e585419369926ab05)
Signed-off-by: Paolo Pisati <paolo.pisati at canonical.com>
---
 drivers/media/usb/dvb-usb-v2/lmedm04.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/lmedm04.c b/drivers/media/usb/dvb-usb-v2/lmedm04.c
index d2a4e6d..1ce7c27 100644
--- a/drivers/media/usb/dvb-usb-v2/lmedm04.c
+++ b/drivers/media/usb/dvb-usb-v2/lmedm04.c
@@ -1110,8 +1110,6 @@ static int dm04_lme2510_frontend_attach(struct dvb_usb_adapter *adap)
 
 		if (adap->fe[0]) {
 			info("FE Found M88RS2000");
-			dvb_attach(ts2020_attach, adap->fe[0], &ts2020_config,
-					&d->i2c_adap);
 			st->i2c_tuner_gate_w = 5;
 			st->i2c_tuner_gate_r = 5;
 			st->i2c_tuner_addr = 0x60;
@@ -1174,17 +1172,18 @@ static int dm04_lme2510_tuner(struct dvb_usb_adapter *adap)
 			ret = st->tuner_config;
 		break;
 	case TUNER_RS2000:
-		ret = st->tuner_config;
+		if (dvb_attach(ts2020_attach, adap->fe[0],
+			       &ts2020_config, &d->i2c_adap))
+			ret = st->tuner_config;
 		break;
 	default:
 		break;
 	}
 
-	if (ret)
+	if (ret) {
 		info("TUN Found %s tuner", tun_msg[ret]);
-	else {
-		info("TUN No tuner found --- resetting device");
-		lme_coldreset(d);
+	} else {
+		info("TUN No tuner found");
 		return -ENODEV;
 	}
 
-- 
2.7.4