V4L/DVB (3804): Tweak bandselect setup fox cx24123

*) Allow forcing the bandselect value with a module parameter to 
facilitate determining the correct bandselect frequencies.
*) Changes the bandselect frequency thresholds based on experiments 
with the above parameter in conjunction with the values in the spec.

Signed-off-by: Yeasah Pell <yeasah at schwide.net>
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 60 insertions, 37 deletions

diff --git a/drivers/media/dvb/frontends/cx24123.c b/drivers/media/dvb/frontends/cx24123.c
index 2aac17451d75..691dc840dcc0 100644
--- a/drivers/media/dvb/frontends/cx24123.c
+++ b/drivers/media/dvb/frontends/cx24123.c
@@ -31,6 +31,7 @@
 
 #define XTAL 10111000
 
+static int force_band;
 static int debug;
 #define dprintk(args...) \
         do { \
@@ -109,65 +110,76 @@ static struct
         u32 progdata;
 } cx24123_bandselect_vals[] =
 {
+        /* band 1 */
         {
                 .freq_low       = 950000,
-                .freq_high      = 1018999,
-                .VCOdivider     = 4,
-                .progdata       = (0 << 18) | (0 << 9) | 0x40,
-        },
-        {
-                .freq_low       = 1019000,
                 .freq_high      = 1074999,
                 .VCOdivider     = 4,
-                .progdata       = (0 << 18) | (0 << 9) | 0x80,
+                .progdata       = (0 << 19) | (0 << 9) | 0x40,
         },
+
+        /* band 2 */
         {
                 .freq_low       = 1075000,
-                .freq_high      = 1227999,
-                .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x01,
+                .freq_high      = 1177999,
+                .VCOdivider     = 4,
+                .progdata       = (0 << 19) | (0 << 9) | 0x80,
         },
+
+        /* band 3 */
         {
-                .freq_low       = 1228000,
-                .freq_high      = 1349999,
+                .freq_low       = 1178000,
+                .freq_high      = 1295999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x02,
+                .progdata       = (0 << 19) | (1 << 9) | 0x01,
         },
+
+        /* band 4 */
         {
-                .freq_low       = 1350000,
-                .freq_high      = 1481999,
+                .freq_low       = 1296000,
+                .freq_high      = 1431999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x04,
+                .progdata       = (0 << 19) | (1 << 9) | 0x02,
         },
+
+        /* band 5 */
         {
-                .freq_low       = 1482000,
-                .freq_high      = 1595999,
+                .freq_low       = 1432000,
+                .freq_high      = 1575999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x08,
+                .progdata       = (0 << 19) | (1 << 9) | 0x04,
         },
+
+        /* band 6 */
         {
-                .freq_low       = 1596000,
+                .freq_low       = 1576000,
                 .freq_high      = 1717999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x10,
+                .progdata       = (0 << 19) | (1 << 9) | 0x08,
         },
+
+        /* band 7 */
         {
                 .freq_low       = 1718000,
                 .freq_high      = 1855999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x20,
+                .progdata       = (0 << 19) | (1 << 9) | 0x10,
         },
+
+        /* band 8 */
         {
                 .freq_low       = 1856000,
                 .freq_high      = 2035999,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x40,
+                .progdata       = (0 << 19) | (1 << 9) | 0x20,
         },
+
+        /* band 9 */
         {
                 .freq_low       = 2036000,
-                .freq_high      = 2149999,
+                .freq_high      = 2150000,
                 .VCOdivider     = 2,
-                .progdata       = (0 << 18) | (1 << 9) | 0x80,
+                .progdata       = (0 << 19) | (1 << 9) | 0x40,
         },
 };
 
@@ -520,6 +532,8 @@ static int cx24123_pll_calculate(struct dvb_frontend* fe, struct dvb_frontend_pa
         u32 ndiv = 0, adiv = 0, vco_div = 0;
         int i = 0;
         int pump = 2;
+        int band = 0;
+        int num_bands = sizeof(cx24123_bandselect_vals) / sizeof(cx24123_bandselect_vals[0]);
 
         /* Defaults for low freq, low rate */
         state->VCAarg = cx24123_AGC_vals[0].VCAprogdata;
@@ -538,21 +552,27 @@ static int cx24123_pll_calculate(struct dvb_frontend* fe, struct dvb_frontend_pa
                 }
         }
 
-        /* For the given frequency, determine the bandselect programming bits */
-        for (i = 0; i < sizeof(cx24123_bandselect_vals) / sizeof(cx24123_bandselect_vals[0]); i++)
+        /* determine the band to use */
+        if(force_band < 1 || force_band > num_bands)
         {
-                if ((cx24123_bandselect_vals[i].freq_low <= p->frequency) &&
-                    (cx24123_bandselect_vals[i].freq_high >= p->frequency) ) {
-                        state->bandselectarg = cx24123_bandselect_vals[i].progdata;
-                        vco_div = cx24123_bandselect_vals[i].VCOdivider;
-
-                        /* determine the charge pump current */
-                        if ( p->frequency < (cx24123_bandselect_vals[i].freq_low + cx24123_bandselect_vals[i].freq_high)/2 )
-                                pump = 0x01;
-                        else
-                                pump = 0x02;
+                for (i = 0; i < num_bands; i++)
+                {
+                        if ((cx24123_bandselect_vals[i].freq_low <= p->frequency) &&
+                            (cx24123_bandselect_vals[i].freq_high >= p->frequency) )
+                                band = i;
                 }
         }
+        else
+                band = force_band - 1;
+
+        state->bandselectarg = cx24123_bandselect_vals[band].progdata;
+        vco_div = cx24123_bandselect_vals[band].VCOdivider;
+
+        /* determine the charge pump current */
+        if ( p->frequency < (cx24123_bandselect_vals[band].freq_low + cx24123_bandselect_vals[band].freq_high)/2 )
+                pump = 0x01;
+        else
+                pump = 0x02;
 
         /* Determine the N/A dividers for the requested lband freq (in kHz). */
         /* Note: the reference divider R=10, frequency is in KHz, XTAL is in Hz */
@@ -1086,6 +1106,9 @@ static struct dvb_frontend_ops cx24123_ops = {
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "Activates frontend debugging (default:0)");
 
+module_param(force_band, int, 0644);
+MODULE_PARM_DESC(force_band, "Force a specific band select (1-9, default:off).");
+
 MODULE_DESCRIPTION("DVB Frontend module for Conexant cx24123/cx24109 hardware");
 MODULE_AUTHOR("Steven Toth");
 MODULE_LICENSE("GPL");