[PATCH 2/6] usb: xhci: Set up endpoints for the first 2 interfaces

[Janne Grunau via B4 Relay]

From: Janne Grunau <j at jannau.net>

Apple USB keyboards carry the HID keyboard boot protocol on the second
interface. Using the second interface in the USB keyboard driver does
not work since the xhci has not allocated a transfer ring.
---
 drivers/usb/host/xhci.c | 31 +++++++++++++++++++------------
 include/usb.h           |  6 ++++++
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 534c4b973f..741e186ee0 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -606,24 +606,28 @@ static int xhci_set_configuration(struct usb_device *udev)
 	int slot_id = udev->slot_id;
 	struct xhci_virt_device *virt_dev = ctrl->devs[slot_id];
 	struct usb_interface *ifdesc;
+	unsigned int ifnum;
+	unsigned int max_ifnum = min((unsigned int)USB_MAX_ACTIVE_INTERFACES,
+				     (unsigned int)udev->config.no_of_if);
 
 	out_ctx = virt_dev->out_ctx;
 	in_ctx = virt_dev->in_ctx;
 
-	num_of_ep = udev->config.if_desc[0].no_of_ep;
-	ifdesc = &udev->config.if_desc[0];
-
 	ctrl_ctx = xhci_get_input_control_ctx(in_ctx);
 	/* Initialize the input context control */
 	ctrl_ctx->add_flags = cpu_to_le32(SLOT_FLAG);
 	ctrl_ctx->drop_flags = 0;
 
-	/* EP_FLAG gives values 1 & 4 for EP1OUT and EP2IN */
-	for (cur_ep = 0; cur_ep < num_of_ep; cur_ep++) {
-		ep_flag = xhci_get_ep_index(&ifdesc->ep_desc[cur_ep]);
-		ctrl_ctx->add_flags |= cpu_to_le32(1 << (ep_flag + 1));
-		if (max_ep_flag < ep_flag)
-			max_ep_flag = ep_flag;
+	for (ifnum = 0; ifnum < max_ifnum; ifnum++) {
+		ifdesc = &udev->config.if_desc[ifnum];
+		num_of_ep = ifdesc->no_of_ep;
+		/* EP_FLAG gives values 1 & 4 for EP1OUT and EP2IN */
+		for (cur_ep = 0; cur_ep < num_of_ep; cur_ep++) {
+			ep_flag = xhci_get_ep_index(&ifdesc->ep_desc[cur_ep]);
+			ctrl_ctx->add_flags |= cpu_to_le32(1 << (ep_flag + 1));
+			if (max_ep_flag < ep_flag)
+				max_ep_flag = ep_flag;
+		}
 	}
 
 	xhci_inval_cache((uintptr_t)out_ctx->bytes, out_ctx->size);
@@ -637,9 +641,12 @@ static int xhci_set_configuration(struct usb_device *udev)
 	xhci_endpoint_copy(ctrl, in_ctx, out_ctx, 0);
 
 	/* filling up ep contexts */
-	err = xhci_init_ep_contexts_if(udev, ctrl, virt_dev, ifdesc);
-	if (err < 0)
-		return err;
+	for (ifnum = 0; ifnum < max_ifnum; ifnum++) {
+		ifdesc = &udev->config.if_desc[ifnum];
+		err = xhci_init_ep_contexts_if(udev, ctrl, virt_dev, ifdesc);
+		if (err < 0)
+			return err;
+	}
 
 	return xhci_configure_endpoints(udev, false);
 }
diff --git a/include/usb.h b/include/usb.h
index 09e3f0cb30..3aafdc8bfd 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -49,6 +49,12 @@ extern bool usb_started; /* flag for the started/stopped USB status */
  */
 #define USB_TIMEOUT_MS(pipe) (usb_pipebulk(pipe) ? 5000 : 1000)
 
+/*
+ * The xhcd hcd driver prepares only a limited number interfaces / endpoints.
+ * Define this limit so that drivers do not exceed it.
+ */
+#define USB_MAX_ACTIVE_INTERFACES	2
+
 /* device request (setup) */
 struct devrequest {
 	__u8	requesttype;

-- 
2.43.2