usb: core: hcd: Create platform devices for onboard hubs in probe()

Call onboard_hub_create/destroy_pdevs() from usb_add/remove_hcd()
for primary HCDs to create/destroy platform devices for onboard
USB hubs that may be connected to the root hub of the controller.
These functions are a NOP unless CONFIG_USB_ONBOARD_HUB=y/m.

Also add a field to struct usb_hcd to keep track of the onboard hub
platform devices that are owned by the HCD.
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20220217104219.v21.3.I7a3a7d9d2126c34079b1cab87aa0b2ec3030f9b7@changeidSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/core/hcd.c

@@ -36,6 +36,7 @@
 #include <linux/phy/phy.h>
 #include <linux/usb.h>
 #include <linux/usb/hcd.h>
+#include <linux/usb/onboard_hub.h>
 #include <linux/usb/otg.h>
 
 #include "usb.h"
@@ -2984,6 +2985,9 @@ int usb_add_hcd(struct usb_hcd *hcd,
 	if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
 		usb_hcd_poll_rh_status(hcd);
 
+	if (usb_hcd_is_primary_hcd(hcd))
+		onboard_hub_create_pdevs(hcd->self.root_hub, &hcd->onboard_hub_devs);
+
 	return retval;
 
 err_register_root_hub:
@@ -3062,6 +3066,8 @@ void usb_remove_hcd(struct usb_hcd *hcd)
 	if (usb_hcd_is_primary_hcd(hcd)) {
 		if (hcd->irq > 0)
 			free_irq(hcd->irq, hcd);
+
+		onboard_hub_destroy_pdevs(&hcd->onboard_hub_devs);
 	}
 
 	usb_deregister_bus(&hcd->self);

include/linux/usb/hcd.h

@@ -198,6 +198,7 @@ struct usb_hcd {
 	struct usb_hcd		*shared_hcd;
 	struct usb_hcd		*primary_hcd;
 
+	struct list_head	onboard_hub_devs;
 
 #define HCD_BUFFER_POOLS	4
 	struct dma_pool		*pool[HCD_BUFFER_POOLS];