[media] zd1301: fix building interface driver without demodulator
If the USB driver is enabled but the demodulator is not, we get a link error:
ERROR: "zd1301_demod_get_dvb_frontend" [drivers/media/usb/dvb-usb-v2/zd1301.ko] undefined!
ERROR: "zd1301_demod_get_i2c_adapter" [drivers/media/usb/dvb-usb-v2/zd1301.ko] undefined!
Such a configuration obviously makes no sense, but we should not fail
the build. This tries to mimic what we have for other drivers by turning
the build failure into a runtime failure.
Alternatively we could use an unconditional 'select' or 'depends on' to enforce
a sane configuration.
Fixes: 47d65372b3b6 ("[media] zd1301_demod: ZyDAS ZD1301 DVB-T demodulator driver")
Fixes: 992b39872b80 ("[media] zd1301: ZyDAS ZD1301 DVB USB interface driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/drivers/media/usb/dvb-usb-v2/zd1301.c b/drivers/media/usb/dvb-usb-v2/zd1301.c
index 563e50c..d1eb4b7 100644
--- a/drivers/media/usb/dvb-usb-v2/zd1301.c
+++ b/drivers/media/usb/dvb-usb-v2/zd1301.c
@@ -168,6 +168,10 @@ static int zd1301_frontend_attach(struct dvb_usb_adapter *adap)
adapter = zd1301_demod_get_i2c_adapter(pdev);
frontend = zd1301_demod_get_dvb_frontend(pdev);
+ if (!adapter || !frontend) {
+ ret = -ENODEV;
+ goto err_module_put_demod;
+ }
/* Add I2C tuner */
dev->mt2060_pdata.i2c_write_max = 9;
