Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

[PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus

4 views
Skip to first unread message

Marius Silaghi

unread,
Dec 23, 2013, 11:40:01 PM12/23/13
to
From: Marius C Silaghi <msil...@fit.edu>

This patch is generated against the last kernel version in the github kernel repository.
Some older families of USB2 cameras (STC-XXXXXUSB) do not support querying only the first 8 bytes of their
device descriptor and therefore fail at enumeration on USB3 HCDs, with babble error -75 as they send more than
the expected 8 bytes. The proposed patch extends the mechanism used for non USB3 HCDs in the first part of
the same function, and successively tries to query both the 8 byte prefix of the device descriptor, as well as
the whole device descriptor (in case the old style query of the 8 byte prefix fails).
In fact, for the cameras I try to fix, the preferred condition is the negation of the one in the proposed patch,
"if (!USE_NEW_SCHEME(retry_counter))", to try first the version successful on this case, but I keep the
current order of the "if" branches to ensure clean continuation of support for other supported devices.

Signed-off-by: Marius C Silaghi <msil...@fit.edu>
---
--- linux/drivers/usb/core/hub.c.orig 2013-12-23 22:09:50.545093470 -0500
+++ linux/drivers/usb/core/hub.c 2013-12-23 22:29:40.521043702 -0500
@@ -4197,7 +4197,19 @@ hub_port_init (struct usb_hub *hub, stru
break;
}

- retval = usb_get_device_descriptor(udev, 8);
+ /* Try first the old 8-byte query (since it may be expected
+ * by some devices), but then give at least a chance to the
+ * new form (retrieving the whole descriptor)!
+ * Querying the content of the whole structure is required
+ * for older USB2 video cameras which do not support partial
+ * descriptor queries, like the STC-XXXUSB family.
+ * Windows also supports them.
+ */
+ if (USE_NEW_SCHEME(retry_counter))
+ retval = usb_get_device_descriptor(udev, 8);
+ else
+ retval = usb_get_device_descriptor(udev,
+ sizeof(struct usb_device_descriptor));
if (retval < 8) {
if (retval != -ENODEV)
dev_err(&udev->dev,

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majo...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Greg Kroah-Hartman

unread,
Jan 7, 2014, 7:40:01 PM1/7/14
to
On Tue, Dec 24, 2013 at 04:19:18AM +0000, Marius Silaghi wrote:
> From: Marius C Silaghi <msil...@fit.edu>
>
> This patch is generated against the last kernel version in the github kernel repository.

We work off of the git.kernel.org trees, not github :)


> Some older families of USB2 cameras (STC-XXXXXUSB) do not support querying only the first 8 bytes of their
> device descriptor and therefore fail at enumeration on USB3 HCDs, with babble error -75 as they send more than
> the expected 8 bytes. The proposed patch extends the mechanism used for non USB3 HCDs in the first part of
> the same function, and successively tries to query both the 8 byte prefix of the device descriptor, as well as
> the whole device descriptor (in case the old style query of the 8 byte prefix fails).
> In fact, for the cameras I try to fix, the preferred condition is the negation of the one in the proposed patch,
> "if (!USE_NEW_SCHEME(retry_counter))", to try first the version successful on this case, but I keep the
> current order of the "if" branches to ensure clean continuation of support for other supported devices.
>
> Signed-off-by: Marius C Silaghi <msil...@fit.edu>

I'll let Sarah take this patch, if it passes her testing.

thanks,

greg k-h

Marius Silaghi

unread,
Jan 7, 2014, 11:10:01 PM1/7/14
to

Great observation,
Sarah located a patch that is queued for the 3.14 kernel and that has a similar effect. So future kernels could work with that one as well.

The patch I provided (being very small and safe) can still be suggested for maintainers of older kernels in various long-term maintained distributions (if you know who is doing that).

Here are some versions of the patch I made for current kernels:

The next one was tested on Ubuntu, applied to the source for 3.5.0-17-generic (Ubuntu)

--- linux-3.5.0/drivers/usb/core/hub.c.orig 2014-01-07 18:16:01.997031650 -0500
+++ linux-3.5.0/drivers/usb/core/hub.c 2014-01-07 18:19:41.617022465 -0500
@@ -4043,7 +4043,11 @@
break;
}

- retval = usb_get_device_descriptor(udev, 8);
+ if (!USE_NEW_SCHEME(retry_counter))
+ retval = usb_get_device_descriptor(udev, 8);
+ else
+ retval = usb_get_device_descriptor(udev,
+ sizeof(struct usb_device_descriptor));
if (retval < 8) {
dev_err(&udev->dev,
"device descriptor read/8, error %d\n",


________________________________________
For kernel 3.9.0-0.4

--- linux-3.5.0/drivers/usb/core/hub.c.orig 2014-01-07 18:16:01.997031650 -0500
+++ linux-3.5.0/drivers/usb/core/hub.c 2014-01-07 18:19:41.617022465 -0500
@@ -4043,7 +4043,11 @@
break;
}

- retval = usb_get_device_descriptor(udev, 8);
+ if (!USE_NEW_SCHEME(retry_counter))
+ retval = usb_get_device_descriptor(udev, 8);
+ else
+ retval = usb_get_device_descriptor(udev,
+ sizeof(struct usb_device_descriptor));
if (retval < 8) {
dev_err(&udev->dev,
"device descriptor read/8, error %d\n",

________________________________________

For kernel 3.10.0-5.15

--- ubuntu-saucy/drivers/usb/core/hub.c.orig 2014-01-07 16:52:41.300835262 -0500
+++ ubuntu-saucy/drivers/usb/core/hub.c 2014-01-07 16:54:53.612829730 -0500
@@ -4126,8 +4126,11 @@
if (USE_NEW_SCHEME(retry_counter) && !(hcd->driver->flags & HCD_USB3))
break;
}
-
- retval = usb_get_device_descriptor(udev, 8);
+ if (!USE_NEW_SCHEME(retry_counter))
+ retval = usb_get_device_descriptor(udev, 8);
+ else
+ retval = usb_get_device_descriptor(udev,
+ sizeof(struct usb_device_descriptor));
if (retval < 8) {
if (retval != -ENODEV)
dev_err(&udev->dev,
________________________________________

For kernel 3.11
--- linux-3.11/drivers/usb/core/hub.c.orig 2014-01-07 16:57:16.352823760 -0500
+++ linux-3.11/drivers/usb/core/hub.c 2014-01-07 16:58:10.168821508 -0500
@@ -4161,7 +4161,11 @@
break;
}

- retval = usb_get_device_descriptor(udev, 8);
+ if (!USE_NEW_SCHEME(retry_counter))
+ retval = usb_get_device_descriptor(udev, 8);
+ else
+ retval = usb_get_device_descriptor(udev,
+ sizeof(struct usb_device_descriptor));
if (retval < 8) {
if (retval != -ENODEV)
dev_err(&udev->dev,


________________________________________
From: linux-u...@vger.kernel.org [linux-u...@vger.kernel.org] on behalf of Greg Kroah-Hartman [gre...@linuxfoundation.org]
Sent: Tuesday, January 07, 2014 19:32
To: Marius Silaghi
Cc: Sarah Sharp; linu...@vger.kernel.org; linux-...@vger.kernel.org; Alan Stern; Lan Tianyu; Xenia Ragiadakou; Jiri Kosina
Subject: Re: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus

On Tue, Dec 24, 2013 at 04:19:18AM +0000, Marius Silaghi wrote:
> From: Marius C Silaghi <msil...@fit.edu>
>
> This patch is generated against the last kernel version in the github kernel repository.

We work off of the git.kernel.org trees, not github :)


> Some older families of USB2 cameras (STC-XXXXXUSB) do not support querying only the first 8 bytes of their
> device descriptor and therefore fail at enumeration on USB3 HCDs, with babble error -75 as they send more than
> the expected 8 bytes. The proposed patch extends the mechanism used for non USB3 HCDs in the first part of
> the same function, and successively tries to query both the 8 byte prefix of the device descriptor, as well as
> the whole device descriptor (in case the old style query of the 8 byte prefix fails).
> In fact, for the cameras I try to fix, the preferred condition is the negation of the one in the proposed patch,
> "if (!USE_NEW_SCHEME(retry_counter))", to try first the version successful on this case, but I keep the
> current order of the "if" branches to ensure clean continuation of support for other supported devices.
>
> Signed-off-by: Marius C Silaghi <msil...@fit.edu>

I'll let Sarah take this patch, if it passes her testing.

thanks,

greg k-h
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in

Jérôme Carretero

unread,
Jan 17, 2014, 11:30:01 PM1/17/14
to
Hi,


I encountered the same problem with another device.
If possible, it would be nice to pick Marius's patch for stable
kernels (tested here on v3.12.6).

There are chances that MacOSX is affected by a similar issue,
so if anybody has friends there...


Thanks,

--
Jérôme
0 new messages