V4L/DVB (12861): tda18271: add support for additional low-power standby modes

By default, the driver enters standby mode with slave tuner output
loop thru enabled and xtal oscillator on.

Not all designs require that slave tuner output loop thru and
xtal oscillator remain active while in standby mode, so two
additional standby modes have been added:

- standby mode with xtal oscillator on (loop thru off)

- total power off
Signed-off-by: Michael Krufky <mkrufky@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/common/tuners/tda18271-fe.c

@@ -1017,9 +1017,17 @@ static int tda18271_sleep(struct dvb_frontend *fe)
 
 	mutex_lock(&priv->lock);
 
-	/* standby mode w/ slave tuner output
-	 * & loop thru & xtal oscillator on */
-	ret = tda18271_set_standby_mode(fe, 1, 0, 0);
+	switch (priv->standby_mode) {
+	case TDA18271_STANDBY_POWER_OFF:
+		ret = tda18271_set_standby_mode(fe, 1, 1, 1);
+		break;
+	case TDA18271_STANDBY_XT_ON:
+		ret = tda18271_set_standby_mode(fe, 1, 1, 0);
+		break;
+	case TDA18271_STANDBY_LT_XT_ON:
+	default:
+		ret = tda18271_set_standby_mode(fe, 1, 0, 0);
+	}
 
 	mutex_unlock(&priv->lock);
 
@@ -1199,6 +1207,8 @@ struct dvb_frontend *tda18271_attach(struct dvb_frontend *fe, u8 addr,
 		priv->gate = (cfg) ? cfg->gate : TDA18271_GATE_AUTO;
 		priv->role = (cfg) ? cfg->role : TDA18271_MASTER;
 		priv->config = (cfg) ? cfg->config : 0;
+		priv->standby_mode = (cfg) ?
+			cfg->standby_mode : TDA18271_STANDBY_LT_XT_ON;
 
 		/* tda18271_cal_on_startup == -1 when cal
 		 * module option is unset */

drivers/media/common/tuners/tda18271-priv.h

@@ -108,6 +108,7 @@ struct tda18271_priv {
 	enum tda18271_role role;
 	enum tda18271_i2c_gate gate;
 	enum tda18271_ver id;
+	enum tda18271_standby_mode standby_mode;
 
 	unsigned int config; /* interface to saa713x / tda829x */
 	unsigned int tm_rfcal;

drivers/media/common/tuners/tda18271.h

@@ -67,6 +67,17 @@ enum tda18271_i2c_gate {
 	TDA18271_GATE_DIGITAL,
 };
 
+enum tda18271_standby_mode {
+	/* slave tuner output & loop thru & xtal oscillator on */
+	TDA18271_STANDBY_LT_XT_ON = 0,
+
+	/* xtal oscillator on */
+	TDA18271_STANDBY_XT_ON,
+
+	/* power off */
+	TDA18271_STANDBY_POWER_OFF,
+};
+
 struct tda18271_config {
 	/* override default if freq / std settings (optional) */
 	struct tda18271_std_map *std_map;
@@ -77,6 +88,9 @@ struct tda18271_config {
 	/* use i2c gate provided by analog or digital demod */
 	enum tda18271_i2c_gate gate;
 
+	/* allow lower power standby modes */
+	enum tda18271_standby_mode standby_mode;
+
 	/* force rf tracking filter calibration on startup */
 	unsigned int rf_cal_on_startup:1;