[PATCH 5/5] xhci: support omitting shared hcd if either of the root hubs has no ports

[Heiner Kallweit]

If either of the root hubs has no ports, then we can get rid of
overhead like the shared hcd. A major internal change is that now
the main hcd can be USB2 or USB3.

Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
---
 drivers/usb/host/xhci-mem.c | 11 +++++------
 drivers/usb/host/xhci.c     |  9 ++++++---
 2 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index a1a17713a..ced139583 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2362,12 +2362,11 @@ static int xhci_setup_port_arrays(struct xhci_hcd *xhci, gfp_t flags)
 		xhci->usb2_rhub.num_ports = USB_MAXCHILDREN;
 	}
 
-	xhci->needs_shared_hcd = 1;
-
-	/*
-	 * Note we could have all USB 3.0 ports, or all USB 2.0 ports.
-	 * Not sure how the USB core will handle a hub with no ports...
-	 */
+	if (xhci->usb2_rhub.num_ports && xhci->usb3_rhub.num_ports)
+		xhci->needs_shared_hcd = 1;
+	else
+		xhci_info(xhci, "USB%u root hub has no ports\n",
+			  xhci->usb2_rhub.num_ports ? 3 : 2);
 
 	xhci_create_rhub_port_array(xhci, &xhci->usb2_rhub, flags);
 	xhci_create_rhub_port_array(xhci, &xhci->usb3_rhub, flags);
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 83a54a566..623901890 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -5279,9 +5279,7 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 
 	xhci = hcd_to_xhci(hcd);
 
-	if (usb_hcd_is_primary_hcd(hcd)) {
-		xhci_hcd_init_usb2_data(xhci, hcd);
-	} else {
+	if (!usb_hcd_is_primary_hcd(hcd)) {
 		xhci_hcd_init_usb3_data(xhci, hcd);
 		return 0;
 	}
@@ -5363,6 +5361,11 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 		return retval;
 	xhci_dbg(xhci, "Called HCD init\n");
 
+	if (xhci_hcd_is_usb3(hcd))
+		xhci_hcd_init_usb3_data(xhci, hcd);
+	else
+		xhci_hcd_init_usb2_data(xhci, hcd);
+
 	xhci_info(xhci, "hcc params 0x%08x hci version 0x%x quirks 0x%016llx\n",
 		  xhci->hcc_params, xhci->hci_version, xhci->quirks);
 
-- 
2.35.1