V4L/DVB (6820): s5h1409: QAM SNR related fixes

QAM SNR values were incorrect when the cable was disconnected. This
patch extends the lookup tables to ensure correct values are being
returned.

Signed-off-by: Steven Toth <stoth@hauppauge.com>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

diff --git a/drivers/media/dvb/frontends/s5h1409.c b/drivers/media/dvb/frontends/s5h1409.c
index 8dee7ec..562d920 100644 (file)
--- a/drivers/media/dvb/frontends/s5h1409.c
+++ b/drivers/media/dvb/frontends/s5h1409.c
@@ -107,7 +107,7 @@ static struct vsb_snr_tab {
        u16     val;
        u16     data;
 } vsb_snr_tab[] = {
-       { 1023, 770, },
+       {  924, 300, },
        {  923, 300, },
        {  918, 295, },
        {  915, 290, },
@@ -154,6 +154,7 @@ static struct qam64_snr_tab {
        u16     val;
        u16     data;
 } qam64_snr_tab[] = {
+       {    1,   0, },
        {   12, 300, },
        {   15, 290, },
        {   18, 280, },
@@ -217,6 +218,7 @@ static struct qam64_snr_tab {
        {   95, 202, },
        {   96, 201, },
        {  104, 200, },
+       {  255,   0, },
 };
 
 /* QAM256 SNR lookup table */
@@ -224,6 +226,7 @@ static struct qam256_snr_tab {
        u16     val;
        u16     data;
 } qam256_snr_tab[] = {
+       {    1,   0, },
        {   12, 400, },
        {   13, 390, },
        {   15, 380, },
@@ -292,6 +295,7 @@ static struct qam256_snr_tab {
        {  105, 262, },
        {  106, 261, },
        {  110, 260, },
+       {  255,   0, },
 };
 
 /* 8 bit registers, 16 bit values */
@@ -670,14 +674,15 @@ static int s5h1409_read_snr(struct dvb_frontend* fe, u16* snr)
        u16 reg;
        dprintk("%s()\n", __FUNCTION__);
 
-       reg = s5h1409_readreg(state, 0xf1) & 0x1ff;
-
        switch(state->current_modulation) {
        case QAM_64:
+               reg = s5h1409_readreg(state, 0xf0) & 0xff;
                return s5h1409_qam64_lookup_snr(fe, snr, reg);
        case QAM_256:
+               reg = s5h1409_readreg(state, 0xf0) & 0xff;
                return s5h1409_qam256_lookup_snr(fe, snr, reg);
        case VSB_8:
+               reg = s5h1409_readreg(state, 0xf1) & 0x3ff;
                return s5h1409_vsb_lookup_snr(fe, snr, reg);
        default:
                break;