[media] si470x: add check to test if this is really a si470x
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
diff --git a/drivers/media/radio/si470x/radio-si470x-usb.c b/drivers/media/radio/si470x/radio-si470x-usb.c
index cd74025..07ef405 100644
--- a/drivers/media/radio/si470x/radio-si470x-usb.c
+++ b/drivers/media/radio/si470x/radio-si470x-usb.c
@@ -635,6 +635,30 @@
}
radio->v4l2_dev.release = si470x_usb_release;
+
+ /*
+ * The si470x SiLabs reference design uses the same USB IDs as
+ * 'Thanko's Raremono' si4734 based receiver. So check here which we
+ * have: attempt to read the device ID from the si470x: the lower 12
+ * bits should be 0x0242 for the si470x.
+ *
+ * We use this check to determine which device we are dealing with.
+ */
+ if (id->idVendor == 0x10c4 && id->idProduct == 0x818a) {
+ retval = usb_control_msg(radio->usbdev,
+ usb_rcvctrlpipe(radio->usbdev, 0),
+ HID_REQ_GET_REPORT,
+ USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
+ 1, 2,
+ radio->usb_buf, 3, 500);
+ if (retval != 3 ||
+ (get_unaligned_be16(&radio->usb_buf[1]) & 0xfff) != 0x0242) {
+ dev_info(&intf->dev, "this is not a si470x device.\n");
+ retval = -ENODEV;
+ goto err_urb;
+ }
+ }
+
retval = v4l2_device_register(&intf->dev, &radio->v4l2_dev);
if (retval < 0) {
dev_err(&intf->dev, "couldn't register v4l2_device\n");