[alsa-devel] [PATCH 17/31] media: au0828 video change to use v4l_enable_media_tuner()

[Shuah Khan]

au0828 is changed to use v4l_enable_media_tuner() to check for
tuner availability from vidioc_g_tuner(), and au0828_v4l2_close(),
before changing tuner settings. If tuner isn't free, return busy
condition from vidioc_g_tuner() and in au0828_v4l2_close() tuner
is left untouched without powering down to save energy.

Signed-off-by: Shuah Khan <shuahkh at osg.samsung.com>
---
 drivers/media/usb/au0828/au0828-video.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/media/usb/au0828/au0828-video.c b/drivers/media/usb/au0828/au0828-video.c
index 32bcc56..ed3ba05 100644
--- a/drivers/media/usb/au0828/au0828-video.c
+++ b/drivers/media/usb/au0828/au0828-video.c
@@ -1010,8 +1010,12 @@ static int au0828_v4l2_close(struct file *filp)
 		goto end;
 
 	if (dev->users == 1) {
-		/* Save some power by putting tuner to sleep */
-		v4l2_device_call_all(&dev->v4l2_dev, 0, core, s_power, 0);
+		/* Save some power by putting tuner to sleep, if it is free */
+		/* What happens when radio is using tuner?? */
+		ret = v4l_enable_media_tuner(vdev);
+		if (ret == 0)
+			v4l2_device_call_all(&dev->v4l2_dev, 0, core,
+					     s_power, 0);
 		dev->std_set_in_tuner_core = 0;
 
 		/* When close the device, set the usb intf0 into alt0 to free
@@ -1412,10 +1416,16 @@ static int vidioc_s_audio(struct file *file, void *priv, const struct v4l2_audio
 static int vidioc_g_tuner(struct file *file, void *priv, struct v4l2_tuner *t)
 {
 	struct au0828_dev *dev = video_drvdata(file);
+	struct video_device *vfd = video_devdata(file);
+	int ret;
 
 	if (t->index != 0)
 		return -EINVAL;
 
+	ret = v4l_enable_media_tuner(vfd);
+	if (ret)
+		return ret;
+
 	dprintk(1, "%s called std_set %d dev_state %d\n", __func__,
 		dev->std_set_in_tuner_core, dev->dev_state);
 
-- 
2.5.0