diff options
Diffstat (limited to 'common/usb_hub.c')
| -rw-r--r-- | common/usb_hub.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/common/usb_hub.c b/common/usb_hub.c index f2a02854f..e4f4e3cd3 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -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); } |