Re: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
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
On Wed, 8 Jan 2014 04:00:22 +
"Marius Silaghi" wrote:
>
> 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.c2014-01-07
> 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(>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.c2014-01-07
> 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(>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(>dev,
>
>
> For kernel 3.11
> --- linux-3.11/drivers/usb/core/hub.c.orig2014-01-07
> 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(>dev,
>
>
> ____
> From: linux-usb-ow...@vger.kernel.org
> [linux-usb-ow...@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; linux-...@vger.kernel.org;
> linux-kernel@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 +, Marius Silaghi wrote:
> > From: Marius C Silaghi
> >
> > This patch is generated against the last kernel version in the
> > github kernel repository.
>
Re: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
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
On Wed, 8 Jan 2014 04:00:22 +
Marius Silaghi msila...@fit.edu wrote:
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.c2014-01-07
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.c2014-01-07
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.orig2014-01-07
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-usb-ow...@vger.kernel.org
[linux-usb-ow...@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; linux-...@vger.kernel.org;
linux-kernel@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 +, Marius Silaghi wrote:
From: Marius C Silaghi msila...@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-XUSB) 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
RE: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
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(>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(>dev,
"device descriptor read/8, error %d\n",
For kernel 3.10.0-5.15
--- ubuntu-saucy/drivers/usb/core/hub.c.orig2014-01-07 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(>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(>dev,
From: linux-usb-ow...@vger.kernel.org [linux-usb-ow...@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; linux-...@vger.kernel.org; linux-kernel@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 +, Marius Silaghi wrote:
> From: Marius C Silaghi
>
> 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-XUSB) 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
Re: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
On Tue, Dec 24, 2013 at 04:19:18AM +, Marius Silaghi wrote: > From: Marius C Silaghi > > 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-XUSB) 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 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-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
On Tue, Dec 24, 2013 at 04:19:18AM +, Marius Silaghi wrote: From: Marius C Silaghi msila...@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-XUSB) 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 msila...@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-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
RE: [PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
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.orig2014-01-07 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-usb-ow...@vger.kernel.org [linux-usb-ow...@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; linux-...@vger.kernel.org; linux-kernel@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 +, Marius Silaghi wrote:
From: Marius C Silaghi msila...@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-XUSB) 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
[PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
From: Marius C Silaghi
This patch is generated against the last kernel version in the github kernel
repository.
Some older families of USB2 cameras (STC-XUSB) 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
---
--- linux/drivers/usb/core/hub.c.orig 2013-12-23 22:09:50.545093470 -0500
+++ linux/drivers/usb/core/hub.c2013-12-23 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(>dev,
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH] usbcore: fix BABBLE failed enumeration of legacy USB2 devices on USB3 bus
From: Marius C Silaghi msila...@fit.edu
This patch is generated against the last kernel version in the github kernel
repository.
Some older families of USB2 cameras (STC-XUSB) 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 msila...@fit.edu
---
--- linux/drivers/usb/core/hub.c.orig 2013-12-23 22:09:50.545093470 -0500
+++ linux/drivers/usb/core/hub.c2013-12-23 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,
--
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