USB: echi-dbgp: increase the controller wait time to come out of halt.
authorColin Ian King <colin.king@canonical.com>
Mon, 30 Jul 2012 15:06:42 +0000 (16:06 +0100)
committerBen Hutchings <ben@decadent.org.uk>
Thu, 9 Aug 2012 23:25:07 +0000 (00:25 +0100)
commit f96a4216e85050c0a9d41a41ecb0ae9d8e39b509 upstream.

The default 10 microsecond delay for the controller to come out of
halt in dbgp_ehci_startup is too short, so increase it to 1 millisecond.

This is based on emperical testing on various USB debug ports on
modern machines such as a Lenovo X220i and an Ivybridge development
platform that needed to wait ~450-950 microseconds.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drivers/usb/early/ehci-dbgp.c

index 1fc8f12..347bb05 100644 (file)
@@ -450,7 +450,7 @@ static int dbgp_ehci_startup(void)
        writel(FLAG_CF, &ehci_regs->configured_flag);
 
        /* Wait until the controller is no longer halted */
-       loop = 10;
+       loop = 1000;
        do {
                status = readl(&ehci_regs->status);
                if (!(status & STS_HALT))