From 756aa6b3d536afe85e151138cb03a293998887b3 Mon Sep 17 00:00:00 2001 From: Christian Engelmayer Date: Wed, 30 May 2007 11:04:48 -0700 Subject: [PATCH] ehci-hub: improved over-current recovery According to the USB Specification Revision 2.0 chapter 11.12.5 a hub experiencing an over-current condition must place all affected ports in the powered-off state. It seems that some root hubs need port power to be cycled by software in order to get back to normal functionality after an over-current condition ... like the EHCI implementation on an MPC8343E. Signed-off-by: Christian Engelmayer Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-hub.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index 27291f50265..71aeca019e8 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -647,9 +647,24 @@ static int ehci_hub_control ( status |= 1 << USB_PORT_FEAT_C_CONNECTION; if (temp & PORT_PEC) status |= 1 << USB_PORT_FEAT_C_ENABLE; - if ((temp & PORT_OCC) && !ignore_oc) + + if ((temp & PORT_OCC) && !ignore_oc){ status |= 1 << USB_PORT_FEAT_C_OVER_CURRENT; + /* + * Hubs should disable port power on over-current. + * However, not all EHCI implementations do this + * automatically, even if they _do_ support per-port + * power switching; they're allowed to just limit the + * current. khubd will turn the power back on. + */ + if (HCS_PPC (ehci->hcs_params)){ + ehci_writel(ehci, + temp & ~(PORT_RWC_BITS | PORT_POWER), + status_reg); + } + } + /* whoever resumes must GetPortStatus to complete it!! */ if (temp & PORT_RESUME) { -- 2.41.1