usb: hub: Power-cycle on root-hub ports

XHCI ports are powered on after a H/W reset, however
EHCI ports are not. So disabling and re-enabling power
on all ports invariably.

Signed-off-by: Amar <amarendra.xt@samsung.com>
Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
This commit is contained in:
Vivek Gautam 2013-04-12 16:34:35 +05:30 committed by Marek Vasut
parent 605bd75af5
commit 020bbcb76b

View File

@ -100,11 +100,45 @@ static void usb_hub_power_on(struct usb_hub_device *hub)
int i;
struct usb_device *dev;
unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
ALLOC_CACHE_ALIGN_BUFFER(struct usb_port_status, portsts, 1);
unsigned short portstatus;
int ret;
dev = hub->pusb_dev;
/* Enable power to the ports */
debug("enabling power on all ports\n");
for (i = 0; i < dev->maxchild; i++) {
/*
* Power-cycle the ports here: aka,
* turning them off and turning on again.
*/
usb_clear_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
debug("port %d returns %lX\n", i + 1, dev->status);
/* Wait at least 2*bPwrOn2PwrGood for PP to change */
mdelay(pgood_delay);
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret < 0) {
debug("port %d: get_port_status failed\n", i + 1);
return;
}
/*
* Check to confirm the state of Port Power:
* xHCI says "After modifying PP, s/w shall read
* PP and confirm that it has reached the desired state
* before modifying it again, undefined behavior may occur
* if this procedure is not followed".
* EHCI doesn't say anything like this, but no harm in keeping
* this.
*/
portstatus = le16_to_cpu(portsts->wPortStatus);
if (portstatus & (USB_PORT_STAT_POWER << 1)) {
debug("port %d: Port power change failed\n", i + 1);
return;
}
usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
debug("port %d returns %lX\n", i + 1, dev->status);
}