V4L/DVB (5034): Pvrusb2: Enable radio mode round #1

This is the logic that supports switching modes via e.g.,
  echo radio > /sys/class/pvrusb2/sn-*/ctl_input/cur_val.

To do the mode switching we need to:
a) broadcast AUDC_SET_RADIO and
b) issue the CX2341X_ENC_MUTE_VIDEO command to the encoder. 

The first is done by adding a new pvr2_i2c_op and having it trigger on 
input change, the second by adding this command in pvr2_encoder_start() 
and requesting an encoder restart on input change by setting 
stale_subsys_mask appropriately. 

The clues about AUDC_SET_RADIO and CX2341X_ENC_MUTE_VIDEO were kindly 
provided by Hans Verkuil on the pvrusb2 mailing list. The idea to 
implement mode switching this way (on input change) is due to Mike Isely.

Why AUDC_SET_RADIO/VIDIOC_S_STD are used for switching? I can 't be sure, 
but I think this can be traced to a cornell student being the first to 
implement radio support in ivtv "as a different standard". I think the 
rest just evolved from there (it 's in the ivtv ML archives).

Signed-off-by: Pantelis Koukousoulas <pakt223@freemail.gr>
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/pvrusb2/pvrusb2-i2c-cmd-v4l2.c b/drivers/media/video/pvrusb2/pvrusb2-i2c-cmd-v4l2.c
index 05ea17a..50fcceb 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-i2c-cmd-v4l2.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-i2c-cmd-v4l2.c
@@ -24,7 +24,7 @@
 #include "pvrusb2-hdw-internal.h"
 #include "pvrusb2-debug.h"
 #include <linux/videodev2.h>
-
+#include <media/v4l2-common.h> /* AUDC_SET_RADIO */
 
 static void set_standard(struct pvr2_hdw *hdw)
 {
@@ -50,6 +50,32 @@
 };
 
 
+static void set_radio(struct pvr2_hdw *hdw)
+{
+	pvr2_trace(PVR2_TRACE_CHIPS,
+			   "i2c v4l2 set_radio()");
+
+	if (hdw->input_val == PVR2_CVAL_INPUT_RADIO) {
+		pvr2_i2c_core_cmd(hdw,AUDC_SET_RADIO,NULL);
+	} else {
+		set_standard(hdw);
+	}
+}
+
+
+static int check_radio(struct pvr2_hdw *hdw)
+{
+	return hdw->input_dirty != 0;
+}
+
+
+const struct pvr2_i2c_op pvr2_i2c_op_v4l2_radio = {
+	.check = check_radio,
+	.update = set_radio,
+	.name = "v4l2_radio",
+};
+
+
 static void set_bcsh(struct pvr2_hdw *hdw)
 {
 	struct v4l2_control ctrl;
@@ -145,7 +171,8 @@
 	memset(&freq,0,sizeof(freq));
 	freq.frequency = fv / 62500;
 	freq.tuner = 0;
-	freq.type = V4L2_TUNER_ANALOG_TV;
+	freq.type = (hdw->input_val == PVR2_CVAL_INPUT_RADIO) ?
+		     V4L2_TUNER_RADIO : V4L2_TUNER_ANALOG_TV;
 	pvr2_i2c_core_cmd(hdw,VIDIOC_S_FREQUENCY,&freq);
 }