From a1a28c6e64b9a6b0b911d066c627bc77f52179fb Mon Sep 17 00:00:00 2001
From: Wolfgang Grandegger <wg@denx.de>
Date: Wed, 21 Dec 2011 00:01:09 +0000
Subject: [PATCH] USB: relax usbcore reset timings
Following the corresponding Linux code, this patch relaxes reset timings
waiting at least 100ms after power to the ports. There are some reports
that it helps make enumeration work better on some high speed devices.
Furthermore, the wait is only done once after power has been enabled
on all ports.
CC: Remy Bohmer <linux@bohmer.net>
CC: Vincent Palatin <vpalatin@chromium.org>
Signed-off-by: Wolfgang Grandegger <wg@denx.de>
---
common/usb_hub.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/common/usb_hub.c b/common/usb_hub.c
index 576e0e6a93..84d0d3f9c1 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -109,6 +109,7 @@ static void usb_hub_power_on(struct usb_hub_device *hub)
{
int i;
struct usb_device *dev;
+ unsigned pgood_delay = hub->desc.bPwrOn2PwrGood * 2;
dev = hub->pusb_dev;
/* Enable power to the ports */
@@ -116,8 +117,10 @@ static void usb_hub_power_on(struct usb_hub_device *hub)
for (i = 0; i < dev->maxchild; i++) {
usb_set_port_feature(dev, i + 1, USB_PORT_FEAT_POWER);
USB_HUB_PRINTF("port %d returns %lX\n", i + 1, dev->status);
- wait_ms(hub->desc.bPwrOn2PwrGood * 2);
}
+
+ /* Wait at least 100 msec for power to become stable */
+ wait_ms(max(pgood_delay, (unsigned)100));
}
void usb_hub_reset(void)
--
2.39.5