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USB: remove short initial timeout for device descriptor fetch

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This patch (as905) removes a micro-optimization from the hub port
initialization code.  Previously we had been using a short timeout on
the first attempt the read the device descriptor; now we will use the
standard timeout length.

It's not clear that the short timeout ever provided any benefit.  And
now we know of one case where it actually hurts: The device can't meet
the short timeout and then it gets terminally confused.

This fixes Bugzilla #8444.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Stern 2007-05-11 10:19:04 -04:00 committed by Greg Kroah-Hartman
parent d984abc97e
commit b89ee19ae6
1 changed files with 4 additions and 9 deletions
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13
drivers/usb/core/hub.c
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@ -2201,14 +2201,9 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
continue;
}
/* Use a short timeout the first time through,
* so that recalcitrant full-speed devices with
* 8- or 16-byte ep0-maxpackets won't slow things
* down tremendously by NAKing the unexpectedly
* early status stage. Also, retry on all errors;
* some devices are flakey.
* 255 is for WUSB devices, we actually need to use 512.
* WUSB1.0[4.8.1].
/* Retry on all errors; some devices are flakey.
* 255 is for WUSB devices, we actually need to use
* 512 (WUSB1.0[4.8.1]).
*/
for (j = 0; j < 3; ++j) {
buf->bMaxPacketSize0 = 0;
@ -2216,7 +2211,7 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
USB_DT_DEVICE << 8, 0,
buf, GET_DESCRIPTOR_BUFSIZE,
(i ? USB_CTRL_GET_TIMEOUT : 1000));
USB_CTRL_GET_TIMEOUT);
switch (buf->bMaxPacketSize0) {
case 8: case 16: case 32: case 64: case 255:
if (buf->bDescriptorType ==