V4L/DVB (12394): cx88: Disable xc3028 power management for Geniatech x8000

A user discovered that the Geniatech x8000 encountered a regression when
the xc3028 power management was introduced.  The xc3028 never recovers after
setting the powerdown register, which is probably because the xc3028 reset
GPIO is not properly configured.  Since I do not have access to the hardware
and thus cannot determine the correct GPIO configuration, just disable xc3028
power management on this board, which fixes the regression.

Thanks to user "ritec" for reporting the issue and testing the fix.

Cc: rictec <rictec@netcabo.pt>
Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/common/tuners/tuner-xc2028.c

@@ -1119,8 +1119,8 @@ static int xc2028_sleep(struct dvb_frontend *fe)
 	struct xc2028_data *priv = fe->tuner_priv;
 	int rc = 0;
 
-	/* Avoid firmware reload on slow devices */
-	if (no_poweroff)
+	/* Avoid firmware reload on slow devices or if PM disabled */
+	if (no_poweroff || priv->ctrl.disable_power_mgmt)
 		return 0;
 
 	tuner_dbg("Putting xc2028/3028 into poweroff mode.\n");

drivers/media/common/tuners/tuner-xc2028.h

@@ -38,6 +38,7 @@ struct xc2028_ctrl {
 	unsigned int		input1:1;
 	unsigned int		vhfbw7:1;
 	unsigned int		uhfbw8:1;
+	unsigned int		disable_power_mgmt:1;
 	unsigned int		demod;
 	enum firmware_type	type:2;
 };

drivers/media/video/cx88/cx88-cards.c

@@ -3003,6 +3003,14 @@ void cx88_setup_xc3028(struct cx88_core *core, struct xc2028_ctrl *ctl)
 	case CX88_BOARD_DVICO_FUSIONHDTV_5_PCI_NANO:
 		ctl->demod = XC3028_FE_OREN538;
 		break;
+	case CX88_BOARD_GENIATECH_X8000_MT:
+		/* FIXME: For this board, the xc3028 never recovers after being
+		   powered down (the reset GPIO probably is not set properly).
+		   We don't have access to the hardware so we cannot determine
+		   which GPIO is used for xc3028, so just disable power xc3028
+		   power management for now */
+		ctl->disable_power_mgmt = 1;
+		break;
 	case CX88_BOARD_WINFAST_TV2000_XP_GLOBAL:
 	case CX88_BOARD_PROLINK_PV_GLOBAL_XTREME:
 	case CX88_BOARD_PROLINK_PV_8000GT: