Some commands to the xHCI hardware cannot be allowed to fail due to out of
memory issues or the command ring being full.
Add a way to reserve a TRB on the command ring, and make all command
queueing functions indicate whether they are using a reserved TRB.
Add a way to pre-allocate all the memory a command might need. A command
needs an input context, a variable to store the status, and (optionally) a
completion for the caller to wait on. Change all code that assumes the
input device context, status, and completion for a command is stored in
the xhci virtual USB device structure (xhci_virt_device).
Store pending completions in a FIFO in xhci_virt_device. Make the event
handler for a configure endpoint command check to see whether a pending
command in the list has completed. We need to use separate input device
contexts for some configure endpoint commands, since multiple drivers can
submit requests at the same time that require a configure endpoint
command.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Refactor common code to set up the add and drop flags for the input device
context setup. This setup is used before a configure endpoint command for
the reset endpoint quirk, and will be used for the command to alloc or
free streams rings.
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The xhci_ring structure contained information that is really related to an
endpoint, not a ring. This will cause problems later when endpoint
streams are supported and there are multiple rings per endpoint.
Move the endpoint state and cancellation information into a new virtual
endpoint structure, xhci_virt_ep. The list of TRBs to be cancelled should
be per endpoint, not per ring, for easy access. There can be only one TRB
that the endpoint stopped on after a stop endpoint command (even with
streams enabled); move the stopped TRB information into the new virtual
endpoint structure. Also move the 31 endpoint rings and temporary ring
storage from the virtual device structure (xhci_virt_device) into the
virtual endpoint structure (xhci_virt_ep).
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In order:
Add reference to relevant section of USBTMC usb488 subclass specs.
Print debug output of capabilities only when it was retrieved successfully.
Clear return value on success, otherwise driver always reports failure.
Signed-off-by: Gergely Imreh <imrehg@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
usb: check for IO errors usb_set_interface can return
if they happen while unbinding a flag is set to retry upon probe
if they happen during probe they are handled as probe errors
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1283) adds a new flag, USBDEVFS_URB_BULK_CONTINUATION,
to usbfs. It is intended for userspace libraries such as libusb and
openusb. When they have to break up a single usbfs bulk transfer into
multiple URBs, they will set the flag on all but the first URB of the
series.
If an error other than an unlink occurs, the kernel will automatically
cancel all the following URBs for the same endpoint and refuse to
accept new submissions, until an URB is encountered that is not marked
as a BULK_CONTINUATION. Such an URB would indicate the start of a new
transfer or the presence of an older library, so the kernel returns to
normal operation.
This enables libraries to delimit bulk transfers correctly, even in
the presence of early termination as indicated by short packets.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This implements support for autosuspend in the sierra driver while online.
Remote wakeup is used for reception. Transmission is facilitated with a queue
and the asynchronous autopm mechanism. To prevent races a private flag
for opened ports and a counter of running transmissions needs to be added.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Tested-by: Elina Pasheva <epasheva@sierrawireless.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In order for the dbgp driver to survive suspend/resume, on every ehci
resume operation the debug controller must get re-initialized.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some EHCI debug controllers after the host controller driver is
activated, the debug controller will occasionally fail to submit a
bulk write URB. On controllers that exhibit this behavior a dummy
bulk write must get submitted to resynchronize the device.
The "dummy bulk write" does not get received by the host attached to
the other end of the usb debug device. The usb debug device simply
acknowledges the "dummy bulk write" and returns to a usable state.
The behavior, without this patch is that you see missing text from a
complete kernel boot when using the keep option to the earlyprintk
kernel argument.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On some EHCI usb debug controllers, the EHCI debug device will fail to
be seen after a port reset, after a warm reset. Two options exist to
get the device to initialize correctly.
Option 1 is to unplug and plug in the device.
Option 2 is to use the EHCI port test to get the usb debug device to
start talking again. At that point the debug controller port reset
will succeed.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
CC: dbrownell@users.sourceforge.net
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If the EHCI debug port is initialized and in use, the EHCI host
controller driver must follow two rules.
1) If the EHCI host driver issues a controller reset, the debug
controller driver re-initialization must get called after the reset
is completed.
2) The EHCI host driver should ignore any requests to the physical
EHCI debug port when the EHCI debug port is in use.
The code to check for the debug port was moved from ehci_pci_reinit()
to ehci_pci_setup because it must get called prior to ehci_reset()
which will clear the debug port registers.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: dbrownell@users.sourceforge.net
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch implements several changes:
1) Improve the capability to debug the dbgp driver
The dbgp_ehci_status() was added in a number of places to report
the critical ehci registers to diagnose the cause of a failure of
the ehci-dbgp driver.
2) Capability to survive the host controller initialization
The dbgp_external_startup(), dbgp_not_safe, and dbgp_phys_port were
added so as to allow the ehci-dbgp to re-initialize after the ehci
host controller is reset by the standard host controller driver.
This same routine is common for the early startup or
re-initialization.
This resulted in the need to move some of the initialization code
out of the __init section because the ehci driver has the
possibility to be loaded later on as a kernel module.
3) Stability improvements for device initialization
The device enumeration from 0 to 127 has the possibility to fail
the first time after a warm reset on some older EHCI debug
controllers. The enumeration will be tried up to 3 times to
account for this failure case.
The dbg_wait_until_complete() was changed to wait up to 250 ms
before failing which only comes into play during device
initialization. The maximum delay will never get hit during the
course of normal operation of the driver, unless the device got
unplugged or there was a ehci controller failure, in which case the
dbgp device driver will shut itself down.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When using the EHCI host controller as a polled device, a bit more
tolerance is required in terms of delays. On some 3+ghz systems the
cpu loops were faster than the EHCI device mmio and resulted in the
controller failing to initialize.
On at least one first generation EHCI controller when it was not
operating in interrupt mode, it would fail to report a port change
status, but executing the port reset allowed the debug controller to
work correctly anyway. This errata causes a one time 300ms delay in
the boot time, where as the typical delay is 1-5ms for an EHCI
controller that does not have this errata.
The debug printk's were fixed to have the correct state messages, and
there was a conversion from using early_printk to printk to avoid
calling the dbgp driver while debugging the initialization.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The PCI quirk code executes a BIOS hand off to obtain full control of
the EHCI host controller, the self contained ehci-dbgp driver must do
the same thing using the early PCI API, else the BIOS can cause a
fatal fault.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: dbrownell@users.sourceforge.net
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The rs232 drivers send a carriage return prior to a new line in the
early printk code.
The usb debug driver should do the same because you want to be able to
use the same terminal programs and tools for analysis of early printk
data.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move the dbgp early printk driver in advance of refactoring and adding
new code, so the changes to this code are tracked separately from the
move of the code.
The drivers/usb/early directory will be the location of the current
and future early usb code for driving usb devices prior initializing
the standard interrupt driven USB drivers.
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We set pdt_1f_for_no_lun for UFI devices, so most floppy entiries should
be unnecessary. This patch removes three entries which I'm certain are.
- For Mitsumi I have a customer with RHEL 5 (bz#514296)
- For SMSC I accessed Novell's Bugzilla and verified the entry
- For Y-E I tested the patch with the actual device
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com>
Signed-off-by: Phil Dibowitz <phil@ipom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
OMAP: ISP1301: Compile fix
Fix this build error on non- OMAP-H2/H3/H4 systems:
(factored out two empty functions as part of the fix)
CC drivers/usb/otg/isp1301_omap.o
drivers/usb/otg/isp1301_omap.c: In function 'otg_update_isp':
drivers/usb/otg/isp1301_omap.c:635: error: implicit declaration of function 'notresponding'
drivers/usb/otg/isp1301_omap.c: In function 'b_peripheral':
drivers/usb/otg/isp1301_omap.c:973: error: implicit declaration of function 'enable_vbus_draw'
drivers/usb/otg/isp1301_omap.c: In function 'isp_update_otg':
drivers/usb/otg/isp1301_omap.c:1003: error: implicit declaration of function 'enable_vbus_source'
make[2]: *** [drivers/usb/otg/isp1301_omap.o] Error 1
make[1]: *** [drivers/usb/otg] Error 2
make: *** [drivers] Error 2
Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The previous code had a bug that would add a trailing null byte to
the returned descriptor.
Signed-off-by: George Spelvin <linux@horizon.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If the driver cannot be registered, put_tty_driver(gs_tty_driver)
occurred here as well as at label fail.
put_tty_driver() already occurs at label fail
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
usb_buffer_map_sg should return negative on error according to
its documentation. But dma_map_sg returns 0 on error. Take this
into account and return -ENOMEM in such situation.
While at it, return -EINVAL instead of -1 when wrong input is
passed in.
If this wasn't done, usb_sg_* operations used after usb_sg_init
which returned 0 may cause oopses/deadlocks since we don't init
structures/entries, esp. completion and status entry.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1281) changes the way ehci-hcd deschedules interrupt
QHs, copying the approach used for async QHs. The caller is no longer
responsible for rescheduling the QH if its queue is non-empty; instead
the reschedule is done directly by intr_deschedule(), after calling
qh_completions(). This is exactly the same as how end_unlink_async()
works.
ehci_urb_dequeue() and intr_deschedule() now correctly handle the case
where they are called while another interrupt URB for the same QH is
being given back. This was a surprisingly large blind spot. And
scan_periodic() now respects the new needs_rescan flag.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1280) fixes an obscure bug in ehci-hcd's dequeuing logic
for async URBs. If a later URB is unlinked and the completion
routine unlinks an earlier URB, then the earlier URB won't be given
back in a timely manner because the endpoint queue isn't rescanned as
it should be.
Similar bugs occur if an endpoint is reset or a halt is cleared while
a completion routine is running, because the subroutines don't test
for the COMPLETING state.
All these problems are solved by adding a new needs_rescan flag to the
ehci_qh structure. If the flag is set while scanning through an idle
QH, the scan will be repeated. If the QH isn't idle then an unlink
cycle will be initiated, and the proper action will be taken when it
becomes idle.
Also, an unnecessary test is removed from qh_link_async(): That
routine is never called if the QH's state isn't IDLE.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Current bindings specify that "fsl,mpc8323-qe-usb" compatible entry
should be used as a base match for QE UDCs, so update the driver to
comply with the bindings.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is how "real" UARTs (e.g. 16550) work and AFAIK what RS232 specifies, too.
Make the driver more compliant.
Signed-off-by: Frank Schaefer <schaefer.frank@gmx.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The device supports it, so why not use it ? Works fine !
Signed-off-by: Frank Schaefer <schaefer.frank@gmx.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
According to the datasheets, the PL2303 supports a set of 25 baudrates.
The baudrate is set as a 4 byte value directly.
During my experiments with device 067b:2303 (PL2303X), I noticed that
- the bridge-controller always uses 9600 baud if invalid/unsupported baud rate
values are set
- the baud rate value returned by usb_control_msg(..., GET_LINE_REQUEST, ...)
does not reflect the actually used baudrate. Always the last set value is
returned, even if it was invalid and not used by the controller.
This patch fixes the following issues with the current code:
1.) make sure that only supported baudrates are set (are there any buggy
chip revisions out there which don't "like" other values... ?).
2.) always set the baudrate to the next nearest supported baudrate.
3.) applications can now read back the resulting baudrate properly, because
tty_encode_baud_rate(...) is now fed with the actually used baudrate.
Signed-off-by: Frank Schaefer <schaefer.frank@gmx.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Using the module parameter vcc_default, you can choose the default VCC value.
Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
You can now set the IUU reader to 3.3V VCC instead of 5V VCC, using the sysfs
parameter vcc_mode. Valid values are 3 and 5.
Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Resetting the device cause the device to have a new name in the /dev.
Signed-off-by: Olivier Bornet <Olivier.Bornet@puck.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Limit data copied to userspace to amount requested. Prevents a faulty
instrument from overwriting user memory.
Signed-off-by: Steve Holland <sdh4@iastate.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The header size should not be included in the number of bytes requested of the
instrument
Signed-off-by: Steve Holland <sdh4@iastate.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Here is a patch to the ch341 driver which adds serial break support.
Signed-off-by: Tim Small <tim@seoss.co.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1275) fixes the s3c2410 device controller driver. Its
usb_gadget_unregister_driver() routine is supposed to call the gadget
driver's unbind method, not the disconnect method.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch adds a CDC EEM ethernet gadget driver. CDC EEM is a newer
USB ethernet specification that uses a simpler interface than the older
CDC ECM. This makes CDC EEM usable by a wider set of USB hardware.
By default the ethernet gadget will still use CDC ECM/Subset, but kernel
configuration and/or a module parameter will allow alternative use of
the CDC EEM protocol.
Changes since last version:
- Brought in missing RNDIS changes that caused compile error
- Modified 'sentinel CRC' checking to match EEM host driver
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These printks can be removed as they only provide information
about the driver not the device and nobody has ever provided
feedback.
Signed-off-by: Oliver Neukum <oliver@neukum.org>
When do_output_char() attempts to write a carriage return/line feed sequence,
it first checks to see how much buffer room is available. If there are at least
two characters free, it will write the carriage return/line feed with two calls
to tty_put_char(). It calls the tty_operation functions write() for devices that
don't support the tty_operations function put_char(). If the USB generic serial
device's write URB is not in use, it will return the buffer size when asked how
much room is available. The write() of the carriage return will cause it to mark
the write URB busy, so the subsequent write() of the line feed will be ignored.
This patch uses the kfifo infrastructure to implement a write FIFO that
accurately returns the amount of space available in the buffer.
Signed-off-by: David VomLehn <dvomlehn@cisco.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove unused variable in ohci-ep93xx.c.
This only shows up when CONFIG_PM is enabled.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
subsys_initcall_sync() is only defined for built-in code, not for
loadable modules, so this driver build fails when built as a module.
However, the _sync() forms of the initcalls are not implemented,
so this should not be used -- just use the non-sync form of it.
drivers/usb/otg/twl4030-usb.c:777: warning: data definition has no type or storage class
drivers/usb/otg/twl4030-usb.c:777: warning: type defaults to 'int' in declaration of 'subsys_initcall_sync'
drivers/usb/otg/twl4030-usb.c:777: warning: parameter names (without types) in function declaration
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Correct priority problem in the use of ! and &.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@ expression E; constant C; @@
- !E & C
+ !(E & C)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch was previously discussed in the following thread:
http://thread.gmane.org/gmane.linux.usb.general/19472/focus=19484
On the OMAP3 device the usbhost controller is in a separate internal
power-domain. So when the usbhost is inactive or suspend is called,
we can disable clocks and power-down the usbhost to save power.
Recently we found that after calling ehci_bus_suspend() and disabling
the usbhost clocks we would see the ehci watchdog timer event fire. This
was causing a kernel panic because the usbhost controllers clocks were
disabled and inside the watchdog timer function the clocks were not
being re-enabled, so when the ehci registers were accessed this resulted
in a CPU data-abort.
To avoid this panic, per recommendation from Alan Stern (see above thread), we
make sure any pending timer events (that may have been scheduled by calling
ehci_work within the ehci_bus_suspend() function) are deleted before returning.
Signed-off-by: Fei Yang <fei.yang@motorola.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes the .probe failure of twl4030_usb driver if
it is compiled into kernel.
Since twl4030_usb USB transceiver .probe depends on
twl4030-regulator, marking twl4030_usb_init as subsys_initcall_sync
can make it called after twl4030-regulator initialization is finished,
then twl4030_usb USB transceiver driver can be probed successfully.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Invoke put_device(musb->xceiv->dev) before musb_platform_exit()as
xceiv is getting unregistered in musb_platform_exit().
Fixes put_device() panic when module insert/removal is performed
multiple times.
Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We are seeing a number of crashes in SMM, when VT-d is enabled while
'Legacy USB support' is enabled in various BIOSes.
The BIOS is supposed to indicate which addresses it uses for DMA in a
special ACPI table ("RMRR"), so that we can punch a hole for it when we
set up the IOMMU.
The problem is, as usual, that BIOS engineers are totally incompetent.
They write code which will crash if the DMA goes AWOL, and then they
either neglect to provide an RMRR table at all, or they put the wrong
addresses in it. And of course they don't do _any_ QA, since that would
take too much time away from their crack-smoking habit.
The real fix, of course, is for consumers to refuse to buy motherboards
which only have closed-source firmware available. If we had _open_
firmware, bugs like this would be easy to fix.
Since that's something I can only dream about, this patch implements an
alternative -- ensuring that the USB controllers are handed off from the
BIOS and quiesced _before_ the IOMMU is initialised. That would have
been a much better design than this RMRR nonsense in the first place, of
course. The bootloader has no business doing DMA after the OS has booted
anyway.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The current limit only allows isochronous transfers up to 32kbyte/urb,
updating this to 192 kbyte/urb improves the reliability of the
transfer. USB 2.0 transfer is possible with 32kbyte but increases the
chance of corrupted/incomplete data when the system is performing some
other tasks in the background.
http://www.spinics.net/lists/linux-usb/msg19955.html
Signed-off-by: Markus Rechberger <mrechberger@gmail.com>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
