From: Hans de Goede <hdegoede@redhat.com>
Date: Sat, 20 Sep 2014 15:03:53 +0000 (+0200)
Subject: usb: Do not power-cycle usb devices on init
X-Git-Tag: v2015.01-rc1~64
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=0834bb2fb0664e02140cd09fb1e06c0d4c60095a;p=oweals%2Fu-boot.git

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>
---

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);