Quoting Peter Chen (2016-07-08 02:04:58)

On Thu, Jul 07, 2016 at 03:20:54PM -0700, Stephen Boyd wrote:

quoted

@@ -39,6 +42,10 @@ static int ulpi_match(struct device *dev, struct device_driver *driver)
      struct ulpi *ulpi = to_ulpi_dev(dev);
      const struct ulpi_device_id *id;
 
+     /* Some ULPI devices don't have a product id so rely on OF match */
+     if (ulpi->id.product == 0)
+             return of_driver_match_device(dev, driver);
+

How about using vendor id? It can't be 0, but pid may be 0.
See: http://www.linux-usb.org/usb.ids

Heikki suggested a product id of 0 would mean we need to use DT
matching. Should it be changed to vendor id instead?

quoted

+static int ulpi_of_register(struct ulpi *ulpi)
+{
+     struct device_node *np = NULL, *child;
+
+     /* Find a ulpi bus underneath the parent or the parent of the parent */
+     if (ulpi->dev.parent->of_node)
+             np = of_find_node_by_name(ulpi->dev.parent->of_node, "ulpi");
+     else if (ulpi->dev.parent->parent && ulpi->dev.parent->parent->of_node)
+             np = of_find_node_by_name(ulpi->dev.parent->parent->of_node,
+                                       "ulpi");
+     if (!np)
+             return 0;
+
+     child = of_get_next_available_child(np, NULL);
+     if (!child)
+             return -EINVAL;

You may need to call of_node_put on parent (np), not on child node
below.

Fixed, thanks.

quoted

+
+     ulpi->dev.of_node = child;
+
+     return 0;
+}
+
+static int ulpi_read_id(struct ulpi *ulpi)
 {
      int ret;
 

@@ -174,14 +218,39 @@ static int ulpi_register(struct device *dev, struct ulpi *ulpi)
      ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW);
      ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8;
 
+     return 0;
+}
+

What does this API for? Why it still needs to be called after
vid/pid gets from firmware?

Ideally we get the vid/pid from the ULPI registers instead of from
firmware. So we typically want to call ulpi_read_id() because most
likely the ulpi-vendor and ulpi-product properties are missing.