[U-Boot] [PATCH v3 2/4] usb: Remove 200 ms delay in usb_hub_port_connect_change()

[Stefan Roese <sr@denx.de>]

This patch removes 2 mdelay(200) calls from usb_hub_port_connect_change().
These delays don't seem to be necessary. At least not in my tests. Here
the number for a custom x86 Bay Trail board (not in mainline yet) with
a quite large and complex USB hub infrastructure.

Without this patch:
starting USB...
USB0:   USB EHCI 1.00
scanning bus 0 for devices... 9 USB Device(s) found

time: 28.415 seconds

With this patch:
starting USB...
USB0:   USB EHCI 1.00
scanning bus 0 for devices... 9 USB Device(s) found

time: 24.003 seconds

So ~4.5 seconds of USB scanning time reduction.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Simon Glass <sjg@chromium.org>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Stephen Warren <swarren@nvidia.com>
Cc: Marek Vasut <marex@denx.de>

---

Changes in v3: None
Changes in v2:
- Make this change unconditional
- Add Acked-by / Tested-by from Hans and Stephen

 common/usb_hub.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/common/usb_hub.c b/common/usb_hub.c
index 2089e20..d621f50 100644
--- a/common/usb_hub.c
+++ b/common/usb_hub.c
@@ -275,7 +275,6 @@ int usb_hub_port_connect_change(struct usb_device *dev, int port)
 		if (!(portstatus & USB_PORT_STAT_CONNECTION))
 			return -ENOTCONN;
 	}
-	mdelay(200);
 
 	/* Reset the port */
 	ret = legacy_hub_port_reset(dev, port, &portstatus);
@@ -285,8 +284,6 @@ int usb_hub_port_connect_change(struct usb_device *dev, int port)
 		return ret;
 	}
 
-	mdelay(200);
-
 	switch (portstatus & USB_PORT_STAT_SPEED_MASK) {
 	case USB_PORT_STAT_SUPER_SPEED:
 		speed = USB_SPEED_SUPER;
-- 
2.7.3