gpu: host1x: Support sub-devices recursively

The display architecture in Tegra186 changes slightly compared to
earlier Tegra generations, which requires that we recursively scan
host1x sub-devices from device tree.

Signed-off-by: Thierry Reding <treding@nvidia.com>

diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index a048e3a..6693abe 100644 (file)
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -45,9 +45,12 @@ struct host1x_subdev {
  * @np: device node
  */
 static int host1x_subdev_add(struct host1x_device *device,
+                            struct host1x_driver *driver,
                             struct device_node *np)
 {
        struct host1x_subdev *subdev;
+       struct device_node *child;
+       int err;
 
        subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
        if (!subdev)
@@ -60,6 +63,19 @@ static int host1x_subdev_add(struct host1x_device *device,
        list_add_tail(&subdev->list, &device->subdevs);
        mutex_unlock(&device->subdevs_lock);
 
+       /* recursively add children */
+       for_each_child_of_node(np, child) {
+               if (of_match_node(driver->subdevs, child) &&
+                   of_device_is_available(child)) {
+                       err = host1x_subdev_add(device, driver, child);
+                       if (err < 0) {
+                               /* XXX cleanup? */
+                               of_node_put(child);
+                               return err;
+                       }
+               }
+       }
+
        return 0;
 }
 
@@ -88,7 +104,7 @@ static int host1x_device_parse_dt(struct host1x_device *device,
        for_each_child_of_node(device->dev.parent->of_node, np) {
                if (of_match_node(driver->subdevs, np) &&
                    of_device_is_available(np)) {
-                       err = host1x_subdev_add(device, np);
+                       err = host1x_subdev_add(device, driver, np);
                        if (err < 0) {
                                of_node_put(np);
                                return err;