[patch] patch #2

2720_usb-ehci-early-handoff-smi.patch (text/plain), 2.32 KB, created by Daniel Drake (RETIRED) on 2006-02-17 08:54:16 UTC

From: David Brownell <[e-mail]>
Date: Thu, 9 Feb 2006 21:35:31 +0000 (-0500)
Subject: [PATCH] USB: fix up the usb early handoff logic for EHCI
X-Git-Url: http://www.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=a38408cd8d6bc0e5d16e609d4b1fdf9ba2e099ce

[PATCH] USB: fix up the usb early handoff logic for EHCI

Disable some dubious "early" USB handoff code that allegedly works around bugs
on some systems (we don't know which ones) but rudely breaks some others.

Also make the kernel warnings reporting BIOS handoff problems be more useful,
reporting the register whose value displays the trouble.

Signed-off-by: David Brownell <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>
---

--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -191,8 +191,9 @@ static void __devinit quirk_usb_handoff_
 		}
 		if (wait_time <= 0)
 			printk(KERN_WARNING "%s %s: BIOS handoff "
-					"failed (BIOS bug ?)\n",
-					pdev->dev.bus_id, "OHCI");
+					"failed (BIOS bug ?) %08x\n",
+					pdev->dev.bus_id, "OHCI",
+					readl(base + OHCI_CONTROL));
 
 		/* reset controller, preserving RWC */
 		writel(control & OHCI_CTRL_RWC, base + OHCI_CONTROL);
@@ -243,6 +244,12 @@ static void __devinit quirk_usb_disable_
 				pr_debug("%s %s: BIOS handoff\n",
 						pdev->dev.bus_id, "EHCI");
 
+#if 0
+/* [e-mail] reports that some systems need SMI forced on,
+ * but that seems dubious in general (the BIOS left it off intentionally)
+ * and is known to prevent some systems from booting.  so we won't do this
+ * unless maybe we can determine when we're on a system that needs SMI forced.
+ */
 				/* BIOS workaround (?): be sure the
 				 * pre-Linux code receives the SMI
 				 */
@@ -252,6 +259,7 @@ static void __devinit quirk_usb_disable_
 				pci_write_config_dword(pdev,
 						offset + EHCI_USBLEGCTLSTS,
 						val | EHCI_USBLEGCTLSTS_SOOE);
+#endif
 			}
 
 			/* always say Linux will own the hardware
@@ -274,8 +282,8 @@ static void __devinit quirk_usb_disable_
 				 * it down, and hope nothing goes too wrong
 				 */
 				printk(KERN_WARNING "%s %s: BIOS handoff "
-						"failed (BIOS bug ?)\n",
-					pdev->dev.bus_id, "EHCI");
+						"failed (BIOS bug ?) %08x\n",
+					pdev->dev.bus_id, "EHCI", cap);
 				pci_write_config_byte(pdev, offset + 2, 0);
 			}