[media] radio-si470x: support seek and tune interrupt enable

Currently we use busy waiting to seek and tune, it can replace to
interrupt way. SI470X I2C driver supports interrupt way to week and tune
via this patch.

Signed-off-by: Joonyoung Shim <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/radio/si470x/radio-si470x-common.c

···
 	if (retval < 0)
 		goto done;
 
-	/* wait till tune operation has completed */
-	timeout = jiffies + msecs_to_jiffies(tune_timeout);
-	do {
-		retval = si470x_get_register(radio, STATUSRSSI);
-		if (retval < 0)
-			goto stop;
-		timed_out = time_after(jiffies, timeout);
-	} while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0) &&
-		(!timed_out));
+	/* currently I2C driver only uses interrupt way to tune */
+	if (radio->stci_enabled) {
+		INIT_COMPLETION(radio->completion);
+
+		/* wait till tune operation has completed */
+		retval = wait_for_completion_timeout(&radio->completion,
+				msecs_to_jiffies(tune_timeout));
+		if (!retval)
+			timed_out = true;
+	} else {
+		/* wait till tune operation has completed */
+		timeout = jiffies + msecs_to_jiffies(tune_timeout);
+		do {
+			retval = si470x_get_register(radio, STATUSRSSI);
+			if (retval < 0)
+				goto stop;
+			timed_out = time_after(jiffies, timeout);
+		} while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
+				&& (!timed_out));
+	}
+
 	if ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
 		dev_warn(&radio->videodev->dev, "tune does not complete\n");
 	if (timed_out)
···
 	if (retval < 0)
 		goto done;
 
-	/* wait till seek operation has completed */
-	timeout = jiffies + msecs_to_jiffies(seek_timeout);
-	do {
-		retval = si470x_get_register(radio, STATUSRSSI);
-		if (retval < 0)
-			goto stop;
-		timed_out = time_after(jiffies, timeout);
-	} while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0) &&
-		(!timed_out));
+	/* currently I2C driver only uses interrupt way to seek */
+	if (radio->stci_enabled) {
+		INIT_COMPLETION(radio->completion);
+
+		/* wait till seek operation has completed */
+		retval = wait_for_completion_timeout(&radio->completion,
+				msecs_to_jiffies(seek_timeout));
+		if (!retval)
+			timed_out = true;
+	} else {
+		/* wait till seek operation has completed */
+		timeout = jiffies + msecs_to_jiffies(seek_timeout);
+		do {
+			retval = si470x_get_register(radio, STATUSRSSI);
+			if (retval < 0)
+				goto stop;
+			timed_out = time_after(jiffies, timeout);
+		} while (((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
+				&& (!timed_out));
+	}
+
 	if ((radio->registers[STATUSRSSI] & STATUSRSSI_STC) == 0)
 		dev_warn(&radio->videodev->dev, "seek does not complete\n");
 	if (radio->registers[STATUSRSSI] & STATUSRSSI_SF)

drivers/media/radio/si470x/radio-si470x-i2c.c

···
 		if (retval < 0)
 			goto done;
 
-		/* enable RDS interrupt */
+		/* enable RDS / STC interrupt */
 		radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
+		radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
 		radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
 		radio->registers[SYSCONFIG1] |= 0x1 << 2;
 		retval = si470x_set_register(radio, SYSCONFIG1);
···
 	unsigned char tmpbuf[3];
 	int retval = 0;
 
+	/* check Seek/Tune Complete */
+	retval = si470x_get_register(radio, STATUSRSSI);
+	if (retval < 0)
+		return;
+
+	if (radio->registers[STATUSRSSI] & STATUSRSSI_STC)
+		complete(&radio->completion);
+
 	/* safety checks */
 	if ((radio->registers[SYSCONFIG1] & SYSCONFIG1_RDS) == 0)
 		return;
 
 	/* Update RDS registers */
-	for (regnr = 0; regnr < RDS_REGISTER_NUM; regnr++) {
+	for (regnr = 1; regnr < RDS_REGISTER_NUM; regnr++) {
 		retval = si470x_get_register(radio, STATUSRSSI + regnr);
 		if (retval < 0)
 			return;
···
 	radio->wr_index = 0;
 	radio->rd_index = 0;
 	init_waitqueue_head(&radio->read_queue);
+
+	/* mark Seek/Tune Complete Interrupt enabled */
+	radio->stci_enabled = true;
+	init_completion(&radio->completion);
 
 	retval = request_irq(client->irq, si470x_i2c_interrupt,
 			IRQF_TRIGGER_FALLING, DRIVER_NAME, radio);

drivers/media/radio/si470x/radio-si470x.h

···
 	unsigned int rd_index;
 	unsigned int wr_index;
 
+	struct completion completion;
+	bool stci_enabled;		/* Seek/Tune Complete Interrupt */
+
 #if defined(CONFIG_USB_SI470X) || defined(CONFIG_USB_SI470X_MODULE)
 	/* reference to USB and video device */
 	struct usb_device *usbdev;