[PATCH] USB: echi-dbgp: increase the controller wait time to come out of halt.

From: Colin Ian King
Date: Mon Jul 30 2012 - 11:06:40 EST


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@xxxxxxxxxxxxx>
---
drivers/usb/early/ehci-dbgp.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/early/ehci-dbgp.c b/drivers/usb/early/ehci-dbgp.c
index ee0ebac..89dcf15 100644
--- a/drivers/usb/early/ehci-dbgp.c
+++ b/drivers/usb/early/ehci-dbgp.c
@@ -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))
--
1.7.10.4

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