[media] rtl2832: implement sleep

Put demod to soft reset in order to save power when sleep. That drops
power usage ~30mA @5V on USB dongle I tested. In real life it does
not matter much as USB IF powers off demod too, but now it is done
twice - demod and USB IF.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index e5f7d7925c85..e80c6b974f4c 100644
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -410,13 +410,23 @@ static int rtl2832_sleep(struct dvb_frontend *fe)
 {
         struct rtl2832_dev *dev = fe->demodulator_priv;
         struct i2c_client *client = dev->client;
+        int ret;
 
         dev_dbg(&client->dev, "\n");
+
         dev->sleeping = true;
         /* stop statistics polling */
         cancel_delayed_work_sync(&dev->stat_work);
         dev->fe_status = 0;
+
+        ret = rtl2832_wr_demod_reg(dev, DVBT_SOFT_RST, 0x1);
+        if (ret)
+                goto err;
+
         return 0;
+err:
+        dev_dbg(&client->dev, "failed=%d\n", ret);
+        return ret;
 }
 
 static int rtl2832_get_tune_settings(struct dvb_frontend *fe,