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>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-encoder.c b/drivers/media/video/pvrusb2/pvrusb2-encoder.c
index c94f97b7939..d094cac9f7a 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-encoder.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-encoder.c
@@ -360,6 +360,9 @@ int pvr2_encoder_start(struct pvr2_hdw *hdw)
         pvr2_hdw_gpio_chg_dir(hdw,0xffffffff,0x00000481);
         pvr2_hdw_gpio_chg_out(hdw,0xffffffff,0x00000000);
 
+        pvr2_encoder_vcmd(hdw,CX2341X_ENC_MUTE_VIDEO,1,
+                          hdw->input_val == PVR2_CVAL_INPUT_RADIO ? 1 : 0);
+
         if (hdw->config == pvr2_config_vbi) {
                 status = pvr2_encoder_vcmd(hdw,CX2341X_ENC_START_CAPTURE,2,
                                            0x01,0x14);