V4L/DVB (9170): cx24116: Sanity checking to data input via S2API to the cx24116 demod.

Add some sanity checking to data input via S2API to the cx24116 demod.
This patch is valid for both s2-mfe and s2.

It was found when testing KAFFEINE with S2API support that invalid
modulation modes amongst other parameters were being delivered to
the demod. In order to debug this sanity checking has been added.

An example session would involve kaffeine setting QAM_AUTO when
querying DVB-T, then later when trying to tune to DVB-S this
cached value would be presented in error.
Signed-off-by: Darron Broad <darron@kewl.org>
Signed-off-by: Steven Toth <stoth@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb/frontends/cx24116.c

@@ -84,7 +84,8 @@ static int debug = 0;
 #define CX24116_ROLLOFF_035 (0x02)
 
 /* pilot bit */
-#define CX24116_PILOT (0x40)
+#define CX24116_PILOT_OFF (0x00)
+#define CX24116_PILOT_ON (0x40)
 
 /* signal status */
 #define CX24116_HAS_SIGNAL   (0x01)
@@ -148,6 +149,7 @@ struct cx24116_tuning
 	u8 fec_val;
 	u8 fec_mask;
 	u8 inversion_val;
+	u8 pilot_val;
 	u8 rolloff_val;
 };
 
@@ -1121,25 +1123,62 @@ static int cx24116_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_par
 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 	struct cx24116_cmd cmd;
 	fe_status_t tunerstat;
-	int i, status, ret, retune = 1;
+	int i, status, ret, retune;
 
 	dprintk("%s()\n",__func__);
 
-	state->dnxt.modulation = c->modulation;
-	state->dnxt.frequency = c->frequency;
-
 	switch(c->delivery_system) {
 		case SYS_DVBS:
 			dprintk("%s: DVB-S delivery system selected\n",__func__);
-			state->dnxt.pilot = PILOT_OFF;
+
+			/* Only QPSK is supported for DVB-S */
+			if(c->modulation != QPSK) {
+				dprintk("%s: unsupported modulation selected (%d)\n",
+					__func__, c->modulation);
+				return -EOPNOTSUPP;
+			}
+
+			/* Pilot doesn't exist in DVB-S, turn bit off */
+			state->dnxt.pilot_val = CX24116_PILOT_OFF;
+			retune = 1;
+
+			/* DVB-S only supports 0.35 */
+			if(c->rolloff != ROLLOFF_35) {
+				dprintk("%s: unsupported rolloff selected (%d)\n",
+					__func__, c->rolloff);
+				return -EOPNOTSUPP;
+			}
 			state->dnxt.rolloff_val = CX24116_ROLLOFF_035;
-			state->dnxt.rolloff = c->rolloff;
 			break;
+
 		case SYS_DVBS2:
 			dprintk("%s: DVB-S2 delivery system selected\n",__func__);
-			if(c->pilot == PILOT_AUTO)
-				retune++;
-			state->dnxt.pilot = c->pilot;
+
+			/*
+			 * NBC 8PSK/QPSK with DVB-S is supported for DVB-S2,
+			 * but not hardware auto detection
+			 */
+			if(c->modulation != _8PSK && c->modulation != NBC_QPSK) {
+				dprintk("%s: unsupported modulation selected (%d)\n",
+					__func__, c->modulation);
+				return -EOPNOTSUPP;
+			}
+
+			switch(c->pilot) {
+				case PILOT_AUTO:	/* Not supported but emulated */
+					retune = 2;	/* Fall-through */
+				case PILOT_OFF:
+					state->dnxt.pilot_val = CX24116_PILOT_OFF;
+					break;
+				case PILOT_ON:
+					state->dnxt.pilot_val = CX24116_PILOT_ON;
+					break;
+				default:
+					dprintk("%s: unsupported pilot mode selected (%d)\n",
+						__func__, c->pilot);
+					return -EOPNOTSUPP;
+			}
+
 			switch(c->rolloff) {
 				case ROLLOFF_20:
 					state->dnxt.rolloff_val= CX24116_ROLLOFF_020;
@@ -1150,20 +1189,28 @@ static int cx24116_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_par
 				case ROLLOFF_35:
 					state->dnxt.rolloff_val= CX24116_ROLLOFF_035;
 					break;
-				case ROLLOFF_AUTO:
+				case ROLLOFF_AUTO:	/* Rolloff must be explicit */
+				default:
+					dprintk("%s: unsupported rolloff selected (%d)\n",
+						__func__, c->rolloff);
 					return -EOPNOTSUPP;
 			}
-			state->dnxt.rolloff = c->rolloff;
 			break;
+
 		default:
 			dprintk("%s: unsupported delivery system selected (%d)\n",
 				__func__, c->delivery_system);
 			return -EOPNOTSUPP;
 	}
+	state->dnxt.modulation = c->modulation;
+	state->dnxt.frequency = c->frequency;
+	state->dnxt.pilot = c->pilot;
+	state->dnxt.rolloff = c->rolloff;
 
 	if ((ret = cx24116_set_inversion(state, c->inversion)) !=  0)
 		return ret;
 
+	/* FEC_NONE/AUTO for DVB-S2 is not supported and detected here */
 	if ((ret = cx24116_set_fec(state, c->modulation, c->fec_inner)) !=  0)
 		return ret;
 
@@ -1173,10 +1220,13 @@ static int cx24116_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_par
 	/* discard the 'current' tuning parameters and prepare to tune */
 	cx24116_clone_params(fe);
 
-	dprintk("%s:   retune      = %d\n", __func__, retune);
-	dprintk("%s:   rolloff     = %d\n", __func__, state->dcur.rolloff);
-	dprintk("%s:   pilot       = %d\n", __func__, state->dcur.pilot);
+	dprintk("%s:   modulation  = %d\n", __func__, state->dcur.modulation);
 	dprintk("%s:   frequency   = %d\n", __func__, state->dcur.frequency);
+	dprintk("%s:   pilot       = %d (val = 0x%02x)\n", __func__,
+		state->dcur.pilot, state->dcur.pilot_val);
+	dprintk("%s:   retune      = %d\n", __func__, retune);
+	dprintk("%s:   rolloff     = %d (val = 0x%02x)\n", __func__,
+		state->dcur.rolloff, state->dcur.rolloff_val);
 	dprintk("%s:   symbol_rate = %d\n", __func__, state->dcur.symbol_rate);
 	dprintk("%s:   FEC         = %d (mask/val = 0x%02x/0x%02x)\n", __func__,
 		state->dcur.fec, state->dcur.fec_mask, state->dcur.fec_val);
@@ -1210,11 +1260,8 @@ static int cx24116_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_par
 	/* Automatic Inversion */
 	cmd.args[0x06] = state->dcur.inversion_val;
 
-	/* Modulation / FEC & Pilot Off */
-	cmd.args[0x07] = state->dcur.fec_val;
-
-	if (state->dcur.pilot == PILOT_ON)
-		cmd.args[0x07] |= CX24116_PILOT;
+	/* Modulation / FEC / Pilot */
+	cmd.args[0x07] = state->dcur.fec_val | state->dcur.pilot_val;
 
 	cmd.args[0x08] = CX24116_SEARCH_RANGE_KHZ >> 8;
 	cmd.args[0x09] = CX24116_SEARCH_RANGE_KHZ & 0xff;
@@ -1277,7 +1324,7 @@ static int cx24116_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_par
 
 		/* Toggle pilot bit when in auto-pilot */
 		if(state->dcur.pilot == PILOT_AUTO)
-			cmd.args[0x07] ^= CX24116_PILOT;
+			cmd.args[0x07] ^= CX24116_PILOT_ON;
 	}
 	while(--retune);