usb: ulpi: add new api functions, {read|write}_dev()

Add these two new api callbacks to struct ulpi_ops. These are different
than read, write in that they pass the parent device directly instead
of via the ops argument.
They are intended to replace the old api functions.

If the new api callbacks are missing, revert to calling the old ones
as before.

Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Tal Shorer <tal.shorer@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/common/ulpi.c

@@ -21,13 +21,17 @@
 
 int ulpi_read(struct ulpi *ulpi, u8 addr)
 {
-	return ulpi->ops->read(ulpi->ops, addr);
+	if (!ulpi->ops->read_dev)
+		return ulpi->ops->read(ulpi->ops, addr);
+	return ulpi->ops->read_dev(ulpi->dev.parent, addr);
 }
 EXPORT_SYMBOL_GPL(ulpi_read);
 
 int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val)
 {
-	return ulpi->ops->write(ulpi->ops, addr, val);
+	if (!ulpi->ops->write_dev)
+		return ulpi->ops->write(ulpi->ops, addr, val);
+	return ulpi->ops->write_dev(ulpi->dev.parent, addr, val);
 }
 EXPORT_SYMBOL_GPL(ulpi_write);