[media] dvb_usb_v2: locked versions of USB bulk IO functions

Implement:
dvb_usbv2_generic_rw_locked()
dvb_usbv2_generic_write_locked()
Caller must hold device lock when locked versions are called.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/usb/dvb-usb-v2/dvb_usb.h

@@ -400,5 +400,9 @@ extern int dvb_usbv2_reset_resume(struct usb_interface *);
 /* the generic read/write method for device control */
 extern int dvb_usbv2_generic_rw(struct dvb_usb_device *, u8 *, u16, u8 *, u16);
 extern int dvb_usbv2_generic_write(struct dvb_usb_device *, u8 *, u16);
+/* caller must hold lock when locked versions are called */
+extern int dvb_usbv2_generic_rw_locked(struct dvb_usb_device *,
+		u8 *, u16, u8 *, u16);
+extern int dvb_usbv2_generic_write_locked(struct dvb_usb_device *, u8 *, u16);
 
 #endif

drivers/media/usb/dvb-usb-v2/dvb_usb_urb.c

@@ -21,8 +21,8 @@
 
 #include "dvb_usb_common.h"
 
-int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
-		u16 rlen)
+int dvb_usb_v2_generic_io(struct dvb_usb_device *d,
+		u8 *wbuf, u16 wlen, u8 *rbuf, u16 rlen)
 {
 	int ret, actual_length;
 
@@ -32,8 +32,6 @@ int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
 		return -EINVAL;
 	}
 
-	mutex_lock(&d->usb_mutex);
-
 	dev_dbg(&d->udev->dev, "%s: >>> %*ph\n", __func__, wlen, wbuf);
 
 	ret = usb_bulk_msg(d->udev, usb_sndbulkpipe(d->udev,
@@ -63,13 +61,43 @@ int dvb_usbv2_generic_rw(struct dvb_usb_device *d, u8 *wbuf, u16 wlen, u8 *rbuf,
 				actual_length, rbuf);
 	}
 
+	return ret;
+}
+
+int dvb_usbv2_generic_rw(struct dvb_usb_device *d,
+		u8 *wbuf, u16 wlen, u8 *rbuf, u16 rlen)
+{
+	int ret;
+
+	mutex_lock(&d->usb_mutex);
+	ret = dvb_usb_v2_generic_io(d, wbuf, wlen, rbuf, rlen);
 	mutex_unlock(&d->usb_mutex);
+
 	return ret;
 }
 EXPORT_SYMBOL(dvb_usbv2_generic_rw);
 
 int dvb_usbv2_generic_write(struct dvb_usb_device *d, u8 *buf, u16 len)
 {
-	return dvb_usbv2_generic_rw(d, buf, len, NULL, 0);
+	int ret;
+
+	mutex_lock(&d->usb_mutex);
+	ret = dvb_usb_v2_generic_io(d, buf, len, NULL, 0);
+	mutex_unlock(&d->usb_mutex);
+
+	return ret;
 }
 EXPORT_SYMBOL(dvb_usbv2_generic_write);
+
+int dvb_usbv2_generic_rw_locked(struct dvb_usb_device *d,
+		u8 *wbuf, u16 wlen, u8 *rbuf, u16 rlen)
+{
+	return dvb_usb_v2_generic_io(d, wbuf, wlen, rbuf, rlen);
+}
+EXPORT_SYMBOL(dvb_usbv2_generic_rw_locked);
+
+int dvb_usbv2_generic_write_locked(struct dvb_usb_device *d, u8 *buf, u16 len)
+{
+	return dvb_usb_v2_generic_io(d, buf, len, NULL, 0);
+}
+EXPORT_SYMBOL(dvb_usbv2_generic_write_locked);