pvrusb2: Enable radio mode round #1

From: Pantelis Koukousoulas <pakt223@freemail.gr>

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).

  --Pantelis

Signed-off-by: Pantelis Koukousoulas <pakt223@freemail.gr>
Signed-off-by: Mike Isely <isely@pobox.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/linux/drivers/media/video/pvrusb2/pvrusb2-encoder.c b/linux/drivers/media/video/pvrusb2/pvrusb2-encoder.c
index ce449763c..b9a04d2b5 100644
--- a/linux/drivers/media/video/pvrusb2/pvrusb2-encoder.c
+++ b/linux/drivers/media/video/pvrusb2/pvrusb2-encoder.c
@@ -393,6 +393,9 @@ 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);