media: radio: Critical interrupt bugfix for si470x over i2c

Fixed si470x_start() disabling the interrupt signal, causing tune operations to never complete. This does not affect USB radios because they poll the registers instead of using the IRQ line.

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diff -uprN linux.orig/drivers/media/radio/si470x/radio-si470x-common.c linux/drivers/media/radio/si470x/radio-si470x-common.c --- linux.orig/drivers/media/radio/si470x/radio-si470x-common.c

2018-01-15 21:58:10.675620432 -0500 +++
linux/drivers/media/radio/si470x/radio-si470x-common.c
2018-01-16 16:54:23.699770645 -0500 @@ -377,8 +377,13 @@ int
si470x_start(struct si470x_device *r goto done; /* sysconfig 1 */
-	radio->registers[SYSCONFIG1] =
-		(de << 11) & SYSCONFIG1_DE;		/* DE*/
+	radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDSIEN;
+	radio->registers[SYSCONFIG1] |= SYSCONFIG1_STCIEN;
+	radio->registers[SYSCONFIG1] |= SYSCONFIG1_RDS;

+ radio->registers[SYSCONFIG1] &= ~SYSCONFIG1_GPIO2;
+ radio->registers[SYSCONFIG1] |= 0x1 << 2;
+ if (de)
+ radio->registers[SYSCONFIG1] |= SYSCONFIG1_DE;
retval = si470x_set_register(radio, SYSCONFIG1); if (retval < 0)
goto done;