V4L/DVB (7303): pvrusb2: Ensure that default input selection is actually valid

Previously the pvrusb2 driver just started with the default input to
be "television".  But if the device doesn't support an analog tuner
then this default must be different.  New logic here selects a
reasonable default based on the actual valid set of available inputs.
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/pvrusb2/pvrusb2-hdw.c

@@ -1875,6 +1875,15 @@ struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf,
 		cptr = hdw->controls + idx;
 		cptr->info = control_defs+idx;
 	}
+
+	/* Ensure that default input choice is a valid one. */
+	m = hdw->input_avail_mask;
+	if (m) for (idx = 0; idx < (sizeof(m) << 3); idx++) {
+		if (!((1 << idx) & m)) continue;
+		hdw->input_val = idx;
+		break;
+	}
+
 	/* Define and configure additional controls from cx2341x module. */
 	hdw->mpeg_ctrl_info = kzalloc(
 		sizeof(*(hdw->mpeg_ctrl_info)) * MPEGDEF_COUNT, GFP_KERNEL);

drivers/media/video/pvrusb2/pvrusb2-hdw.h

@@ -41,8 +41,8 @@
 /* Legal values for the INPUT state variable */
 #define PVR2_CVAL_INPUT_TV 0
 #define PVR2_CVAL_INPUT_DTV 1
-#define PVR2_CVAL_INPUT_SVIDEO 2
-#define PVR2_CVAL_INPUT_COMPOSITE 3
+#define PVR2_CVAL_INPUT_COMPOSITE 2
+#define PVR2_CVAL_INPUT_SVIDEO 3
 #define PVR2_CVAL_INPUT_RADIO 4
 
 enum pvr2_config {