Genpix driver is broken (no 8psk lock). Here's why & how to fix.

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Over a month ago I reported a problem with a change that was made to
the Genpix driver which broke 8PSK.  The change limited DVB-S streams
to QPSK and 8PSK to DVB-S2.  There are a couple problems with this.
First of all, Genpix devices do NOT support DVB-S2 but pretends to for
access to 8PSK.  Secondly, the 8PSK the Genpix provides is modified,
aka 8PSK turbo-fec.  Two of the biggest North American DVB-S providers
use 8PSK turbo-fec for a lot of their content.  Therefore, limiting
DVB-S to QPSK only is crippling reception of all those providers
transponders which use it.

Ideally 8PSK should be allowed for DVB-S in v4l so that a device like
the Genpix doesn't have to pretend to be something it's not to use it.
 While I seriously doubt that will be fixed, this problem can still be
resolved by simply reverting back to the drivers original behavior
with the following patch:

diff -pruN v4l-dvb.orig/linux/drivers/media/dvb/dvb-usb/gp8psk-fe.c
v4l-dvb/linux/drivers/media/dvb/dvb-usb/gp8psk-fe.c
--- v4l-dvb.orig/linux/drivers/media/dvb/dvb-usb/gp8psk-fe.c
2009-08-14 19:17:43.000000000 -0700
+++ v4l-dvb/linux/drivers/media/dvb/dvb-usb/gp8psk-fe.c 2009-08-14
19:19:18.000000000 -0700
@@ -146,8 +146,8 @@ static int gp8psk_fe_set_frontend(struct

        switch (c->delivery_system) {
        case SYS_DVBS:
-               /* Only QPSK is supported for DVB-S */
-               if (c->modulation != QPSK) {
+               /* Allow QPSK and 8PSK */
+               if (c->modulation != QPSK && c->modulation != PSK_8) {
                        deb_fe("%s: unsupported modulation selected (%d)\n",
                                __func__, c->modulation);
                        return -EOPNOTSUPP;
--
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