From 0834bb2fb0664e02140cd09fb1e06c0d4c60095a Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sat, 20 Sep 2014 17:03:53 +0200 Subject: [PATCH] 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 --- common/usb_hub.c | 39 --------------------------------------- 1 file changed, 39 deletions(-) diff --git a/common/usb_hub.c b/common/usb_hub.c index c416e5e0b3..0f1eab4486 100644 --- a/common/usb_hub.c +++ b/common/usb_hub.c @@ -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); -- 2.39.5