USB: ehci: make debug port in-use detection functional again

Debug port in-use determination must be done before the controller gets
reset the first time, i.e. before the call to ehci_setup() as of commit
1a49e2ac9651df7349867a5cf44e2c83de1046af. That commit effectively
rendered commit 9fa5780beea1274d498a224822397100022da7d4 useless.

While moving that code around, also fix the BAR determination - the
respective capability field is a 3- rather than a 2-bit one -, and use
PCI_CAP_ID_DBG instead of the literal 0x0a.

It's unclear to me whether the debug port functionality is important
enough to warrant fixing this in stable kernels too.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 20 insertions, 19 deletions

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index dabb20494826..170b9399e09f 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -200,6 +200,26 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
                 break;
         }
 
+        /* optional debug port, normally in the first BAR */
+        temp = pci_find_capability(pdev, PCI_CAP_ID_DBG);
+        if (temp) {
+                pci_read_config_dword(pdev, temp, &temp);
+                temp >>= 16;
+                if (((temp >> 13) & 7) == 1) {
+                        u32 hcs_params = ehci_readl(ehci,
+                                                    &ehci->caps->hcs_params);
+
+                        temp &= 0x1fff;
+                        ehci->debug = hcd->regs + temp;
+                        temp = ehci_readl(ehci, &ehci->debug->control);
+                        ehci_info(ehci, "debug port %d%s\n",
+                                  HCS_DEBUG_PORT(hcs_params),
+                                  (temp & DBGP_ENABLED) ? " IN USE" : "");
+                        if (!(temp & DBGP_ENABLED))
+                                ehci->debug = NULL;
+                }
+        }
+
         retval = ehci_setup(hcd);
         if (retval)
                 return retval;
@@ -228,25 +248,6 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
                 break;
         }
 
-        /* optional debug port, normally in the first BAR */
-        temp = pci_find_capability(pdev, 0x0a);
-        if (temp) {
-                pci_read_config_dword(pdev, temp, &temp);
-                temp >>= 16;
-                if ((temp & (3 << 13)) == (1 << 13)) {
-                        temp &= 0x1fff;
-                        ehci->debug = hcd->regs + temp;
-                        temp = ehci_readl(ehci, &ehci->debug->control);
-                        ehci_info(ehci, "debug port %d%s\n",
-                                HCS_DEBUG_PORT(ehci->hcs_params),
-                                (temp & DBGP_ENABLED)
-                                        ? " IN USE"
-                                        : "");
-                        if (!(temp & DBGP_ENABLED))
-                                ehci->debug = NULL;
-                }
-        }
-
         /* at least the Genesys GL880S needs fixup here */
         temp = HCS_N_CC(ehci->hcs_params) * HCS_N_PCC(ehci->hcs_params);
         temp &= 0x0f;