[PATCH 2/4] usb: typec: Add typec_port_register_altmodes_from_fwnode()

[Hans de Goede <hdegoede@redhat.com>]

This can be used by Type-C controller drivers which use a standard
usb-connector fwnode, with altmodes sub-node, to describe the available
altmodes.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/usb/typec/class.c | 56 +++++++++++++++++++++++++++++++++++++++
 include/linux/usb/typec.h |  7 +++++
 2 files changed, 63 insertions(+)

diff --git a/drivers/usb/typec/class.c b/drivers/usb/typec/class.c
index c9234748537a..47de2b2e3d54 100644
--- a/drivers/usb/typec/class.c
+++ b/drivers/usb/typec/class.c
@@ -1607,6 +1607,62 @@ typec_port_register_altmode(struct typec_port *port,
 }
 EXPORT_SYMBOL_GPL(typec_port_register_altmode);
 
+void typec_port_register_altmodes_from_fwnode(struct typec_port *port,
+	const struct typec_altmode_ops *ops, void *drvdata,
+	struct typec_altmode **altmodes, size_t n,
+	struct fwnode_handle *fwnode)
+{
+	struct fwnode_handle *altmodes_node, *child;
+	struct typec_altmode_desc desc;
+	struct typec_altmode *alt;
+	size_t index = 0;
+	u32 svid, vdo;
+	int ret;
+
+	altmodes_node = fwnode_get_named_child_node(fwnode, "altmodes");
+	if (!altmodes_node)
+		return;
+
+	child = NULL;
+	while ((child = fwnode_get_next_child_node(altmodes_node, child))) {
+		ret = fwnode_property_read_u32(child, "svid", &svid);
+		if (ret) {
+			dev_err(&port->dev, "Error reading svid for altmode %s\n",
+				fwnode_get_name(child));
+			continue;
+		}
+
+		ret = fwnode_property_read_u32(child, "vdo", &vdo);
+		if (ret) {
+			dev_err(&port->dev, "Error reading vdo for altmode %s\n",
+				fwnode_get_name(child));
+			continue;
+		}
+
+		if (index >= n) {
+			dev_err(&port->dev, "Error not enough space for altmode %s\n",
+				fwnode_get_name(child));
+			continue;
+		}
+
+		desc.svid = svid;
+		desc.vdo = vdo;
+		desc.mode = index + 1;
+		alt = typec_port_register_altmode(port, &desc);
+		if (IS_ERR(alt)) {
+			dev_err(&port->dev, "Error registering altmode %s\n",
+				fwnode_get_name(child));
+			continue;
+		}
+
+		alt->ops = ops;
+		typec_altmode_set_drvdata(alt, drvdata);
+		altmodes[index] = alt;
+		index++;
+	}
+}
+EXPORT_SYMBOL_GPL(typec_port_register_altmodes_from_fwnode);
+
 /**
  * typec_register_port - Register a USB Type-C Port
  * @parent: Parent device
diff --git a/include/linux/usb/typec.h b/include/linux/usb/typec.h
index 5daa1c49761c..fbe4bccb3a98 100644
--- a/include/linux/usb/typec.h
+++ b/include/linux/usb/typec.h
@@ -17,6 +17,7 @@ struct typec_partner;
 struct typec_cable;
 struct typec_plug;
 struct typec_port;
+struct typec_altmode_ops;
 
 struct fwnode_handle;
 struct device;
@@ -121,6 +122,12 @@ struct typec_altmode
 struct typec_altmode
 *typec_port_register_altmode(struct typec_port *port,
 			     const struct typec_altmode_desc *desc);
+
+void typec_port_register_altmodes_from_fwnode(struct typec_port *port,
+	const struct typec_altmode_ops *ops, void *drvdata,
+	struct typec_altmode **altmodes, size_t n,
+	struct fwnode_handle *fwnode);
+
 void typec_unregister_altmode(struct typec_altmode *altmode);
 
 struct typec_port *typec_altmode2port(struct typec_altmode *alt);
-- 
2.26.2