diff options
Diffstat (limited to 'drivers/usb/core/of.c')
| -rw-r--r-- | drivers/usb/core/of.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/usb/core/of.c b/drivers/usb/core/of.c index db4ccf9ce3d9..f1a499ee482c 100644 --- a/drivers/usb/core/of.c +++ b/drivers/usb/core/of.c @@ -8,6 +8,7 @@ */ #include <linux/of.h> +#include <linux/of_graph.h> #include <linux/usb/of.h> /** @@ -75,6 +76,76 @@ bool usb_of_has_combined_node(struct usb_device *udev) } EXPORT_SYMBOL_GPL(usb_of_has_combined_node); +static bool usb_of_has_devices_or_graph(const struct usb_device *hub) +{ + const struct device_node *np = hub->dev.of_node; + struct device_node *child; + + if (of_graph_is_present(np)) + return true; + + for_each_child_of_node(np, child) + if (of_property_present(child, "reg")) + return true; + + return false; +} + +/** + * usb_of_get_connect_type() - get a USB hub's port connect_type + * @hub: hub to which port is for @port1 + * @port1: one-based index of port + * + * Get the connect_type of @port1 based on the device node for @hub. If the + * port is described in the OF graph, the connect_type is "hotplug". If the + * @hub has a child device has with a 'reg' property equal to @port1 the + * connect_type is "hard-wired". If there isn't an OF graph or child node at + * all then the connect_type is "unknown". Otherwise, the port is considered + * "unused" because it isn't described at all. + * + * Return: A connect_type for @port1 based on the device node for @hub. + */ +enum usb_port_connect_type usb_of_get_connect_type(struct usb_device *hub, int port1) +{ + struct device_node *np, *child, *ep, *remote_np; + enum usb_port_connect_type connect_type; + + /* Only set connect_type if binding has ports/hardwired devices. */ + if (!usb_of_has_devices_or_graph(hub)) + return USB_PORT_CONNECT_TYPE_UNKNOWN; + + /* Assume port is unused if there's a graph or a child node. */ + connect_type = USB_PORT_NOT_USED; + + np = hub->dev.of_node; + /* + * Hotplug ports are connected to an available remote node, e.g. + * usb-a-connector compatible node, in the OF graph. + */ + if (of_graph_is_present(np)) { + ep = of_graph_get_endpoint_by_regs(np, port1, -1); + if (ep) { + remote_np = of_graph_get_remote_port_parent(ep); + of_node_put(ep); + if (of_device_is_available(remote_np)) + connect_type = USB_PORT_CONNECT_TYPE_HOT_PLUG; + of_node_put(remote_np); + } + } + + /* + * Hard-wired ports are child nodes with a reg property corresponding + * to the port number, i.e. a usb device. + */ + child = usb_of_get_device_node(hub, port1); + if (of_device_is_available(child)) + connect_type = USB_PORT_CONNECT_TYPE_HARD_WIRED; + of_node_put(child); + + return connect_type; +} +EXPORT_SYMBOL_GPL(usb_of_get_connect_type); + /** * usb_of_get_interface_node() - get a USB interface node * @udev: USB device of interface |