From: Hans de Goede <hdegoede@redhat.com>
Date: Fri, 15 Nov 2013 11:14:38 +0000 (+0100)
Subject: xhci: Handle MaxPSASize == 0
X-Git-Tag: v3.15-rc1~137^2~26^2~37
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=f7920884eb640bc642f3b4e56f5237d30a080eda;p=karo-tx-linux.git

xhci: Handle MaxPSASize == 0

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
---

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 6cb9c2235a0b..1db3c2794a49 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -3138,6 +3138,12 @@ int xhci_alloc_streams(struct usb_hcd *hcd, struct usb_device *udev,
 	xhci_dbg(xhci, "Driver wants %u stream IDs (including stream 0).\n",
 			num_streams);
 
+	/* MaxPSASize value 0 (2 streams) means streams are not supported */
+	if (HCC_MAX_PSA(xhci->hcc_params) < 4) {
+		xhci_dbg(xhci, "xHCI controller does not support streams.\n");
+		return -ENOSYS;
+	}
+
 	config_cmd = xhci_alloc_command(xhci, true, true, mem_flags);
 	if (!config_cmd) {
 		xhci_dbg(xhci, "Could not allocate xHCI command structure.\n");