[PATCH 23/78] EHCI: add delay to bus_resume before accessing ports
Greg Kroah-Hartman <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
From: Alan Stern <[email protected]> This patch (as870) adds a delay to ehci-hcd's bus_resume routine. Apparently there are controllers and/or BIOSes out there which need such a delay to get the ports back into their correct state. This fixes Bugzilla #8190. Signed-off-by: Alan Stern <[email protected]> Cc: David Brownell <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/usb/host/ehci-hub.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index 1813b7c..f4d301b 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -136,6 +136,10 @@ static int ehci_bus_resume (struct usb_hcd *hcd) /* restore CMD_RUN, framelist size, and irq threshold */ ehci_writel(ehci, ehci->command, &ehci->regs->command); + /* Some controller/firmware combinations need a delay during which + * they set up the port statuses. See Bugzilla #8190. */ + mdelay(8); + /* manually resume the ports we suspended during bus_suspend() */ i = HCS_N_PORTS (ehci->hcs_params); while (i--) { -- 1.5.1.2 ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel