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usb: Do not power-cycle usb devices on init

Do as the Linux kernel does and power on any ports which are not yet one,
this is enough.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
utp
Hans de Goede 2014-09-20 17:03:53 +02:00 committed by Marek Vasut
parent f7b9baf755
commit 0834bb2fb0
1 changed files with 0 additions and 39 deletions

View File

@ -86,49 +86,10 @@ 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:
* Here we Power-cycle the ports: aka,
* turning them off and turning on again.
*/
debug("enabling power on all ports\n");
for (i = 0; i < dev->maxchild; i++) {
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);
for (i = 0; i < dev->maxchild; i++) {
ret = usb_get_port_status(dev, i + 1, portsts);
if (ret < 0) {
debug("port %d: get_port_status failed\n", i + 1);
continue;
}
/*
* 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);
continue;
}
}
for (i = 0; i < dev->maxchild; i++) {
usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
debug("port %d returns %lX\n", i + 1, dev->status);