V4L/DVB (7944): tuner-xc2028: use hybrid_tuner_request_state

Use a standard method to manage multiple instances of a hybrid tuner.
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/common/tuners/tuner-xc2028.c

@@ -46,7 +46,7 @@ module_param_string(firmware_name, firmware_name, sizeof(firmware_name), 0);
 MODULE_PARM_DESC(firmware_name, "Firmware file name. Allows overriding the "
 				"default firmware name\n");
 
-static LIST_HEAD(xc2028_list);
+static LIST_HEAD(hybrid_tuner_instance_list);
 static DEFINE_MUTEX(xc2028_list_mutex);
 
 /* struct for storing firmware table */
@@ -68,12 +68,11 @@ struct firmware_properties {
 };
 
 struct xc2028_data {
-	struct list_head        xc2028_list;
+	struct list_head        hybrid_tuner_instance_list;
 	struct tuner_i2c_props  i2c_props;
 	int                     (*tuner_callback) (void *dev,
 						   int command, int arg);
 	void			*video_dev;
-	int			count;
 	__u32			frequency;
 
 	struct firmware_description *firm;
@@ -1072,20 +1071,19 @@ static int xc2028_dvb_release(struct dvb_frontend *fe)
 
 	mutex_lock(&xc2028_list_mutex);
 
-	priv->count--;
-
-	if (!priv->count) {
-		list_del(&priv->xc2028_list);
-
+	/* only perform final cleanup if this is the last instance */
+	if (hybrid_tuner_report_instance_count(priv) == 1) {
 		kfree(priv->ctrl.fname);
-
 		free_firmware(priv);
-		kfree(priv);
-		fe->tuner_priv = NULL;
 	}
 
+	if (priv)
+		hybrid_tuner_release_state(priv);
+
 	mutex_unlock(&xc2028_list_mutex);
 
+	fe->tuner_priv = NULL;
+
 	return 0;
 }
 
@@ -1150,7 +1148,7 @@ struct dvb_frontend *xc2028_attach(struct dvb_frontend *fe,
 				   struct xc2028_config *cfg)
 {
 	struct xc2028_data *priv;
-	void               *video_dev;
+	int instance;
 
 	if (debug)
 		printk(KERN_DEBUG "xc2028: Xcv2028/3028 init called!\n");
@@ -1163,48 +1161,40 @@ struct dvb_frontend *xc2028_attach(struct dvb_frontend *fe,
 		return NULL;
 	}
 
-	video_dev = cfg->i2c_adap->algo_data;
-
-	if (debug)
-		printk(KERN_DEBUG "xc2028: video_dev =%p\n", video_dev);
-
 	mutex_lock(&xc2028_list_mutex);
 
-	list_for_each_entry(priv, &xc2028_list, xc2028_list) {
-		if (&priv->i2c_props.adap->dev == &cfg->i2c_adap->dev) {
-			video_dev = NULL;
-			if (debug)
-				printk(KERN_DEBUG "xc2028: reusing device\n");
-
-			break;
-		}
-	}
-
-	if (video_dev) {
-		priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-		if (priv == NULL) {
-			mutex_unlock(&xc2028_list_mutex);
-			return NULL;
-		}
-
-		priv->i2c_props.addr = cfg->i2c_addr;
-		priv->i2c_props.adap = cfg->i2c_adap;
-		priv->i2c_props.name = "xc2028";
-
-		priv->video_dev = video_dev;
+	instance = hybrid_tuner_request_state(struct xc2028_data, priv,
+					      hybrid_tuner_instance_list,
+					      cfg->i2c_adap, cfg->i2c_addr,
+					      "xc2028");
+	switch (instance) {
+	case 0:
+		/* memory allocation failure */
+		goto fail;
+		break;
+	case 1:
+		/* new tuner instance */
 		priv->tuner_callback = cfg->callback;
 		priv->ctrl.max_len = 13;
 
 		mutex_init(&priv->lock);
 
-		list_add_tail(&priv->xc2028_list, &xc2028_list);
-	}
-
-	fe->tuner_priv = priv;
-	priv->count++;
+		/* analog side (tuner-core) uses i2c_adap->algo_data.
+		 * digital side is not guaranteed to have algo_data defined.
+		 *
+		 * digital side will always have fe->dvb defined.
+		 * analog side (tuner-core) doesn't (yet) define fe->dvb.
+		 */
+		priv->video_dev = ((fe->dvb) && (fe->dvb->priv)) ?
+				   fe->dvb->priv : cfg->i2c_adap->algo_data;
 
-	if (debug)
-		printk(KERN_DEBUG "xc2028: usage count is %i\n", priv->count);
+		fe->tuner_priv = priv;
+		break;
+	case 2:
+		/* existing tuner instance */
+		fe->tuner_priv = priv;
+		break;
+	}
 
 	memcpy(&fe->ops.tuner_ops, &xc2028_dvb_tuner_ops,
 	       sizeof(xc2028_dvb_tuner_ops));
@@ -1217,6 +1207,11 @@ struct dvb_frontend *xc2028_attach(struct dvb_frontend *fe,
 	mutex_unlock(&xc2028_list_mutex);
 
 	return fe;
+fail:
+	mutex_unlock(&xc2028_list_mutex);
+
+	xc2028_dvb_release(fe);
+	return NULL;
 }
 
 EXPORT_SYMBOL(xc2028_attach);