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  1. 01 2月, 2015 2 次提交
  3. 25 1月, 2015 2 次提交
    • D
      usb: core: hub: modify hub reset logic in hub driver · fbaecff0
      由 Deepak Das 提交于 
      Currently if port power is turned off by user on hub port
using USBDEVFS then port power is turned back ON
by hub driver.
This commit modifies hub reset logic in hub_port_connect() to prevent
hub driver from turning back the port power ON if port is not owned
by kernel.
Signed-off-by: NDeepak Das <deepakdas.linux@gmail.com>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      fbaecff0
    • A
      USB: don't cancel queued resets when unbinding drivers · 524134d4
      由 Alan Stern 提交于 
      The USB stack provides a mechanism for drivers to request an
asynchronous device reset (usb_queue_reset_device()).  The mechanism
uses a work item (reset_ws) embedded in the usb_interface structure
used by the driver, and the reset is carried out by a work queue
routine.

The asynchronous reset can race with driver unbinding.  When this
happens, we try to cancel the queued reset before unbinding the
driver, on the theory that the driver won't care about any resets once
it is unbound.

However, thanks to the fact that lockdep now tracks work queue
accesses, this can provoke a lockdep warning in situations where the
device reset causes another interface's driver to be unbound; see

	http://marc.info/?l=linux-usb&m=141893165203776&w=2

for an example.  The reason is that the work routine for reset_ws in
one interface calls cancel_queued_work() for the reset_ws in another
interface.  Lockdep thinks this might lead to a work routine trying to
cancel itself.  The simplest solution is not to cancel queued resets
when unbinding drivers.

This means we now need to acquire a reference to the usb_interface
when queuing a reset_ws work item and to drop the reference when the
work routine finishes.  We also need to make sure that the
usb_interface structure doesn't outlive its parent usb_device; this
means acquiring and dropping a reference when the interface is created
and destroyed.

In addition, cancelling a queued reset can fail (if the device is in
the middle of an earlier reset), and this can cause usb_reset_device()
to try to rebind an interface that has been deallocated (see
http://marc.info/?l=linux-usb&m=142175717016628&w=2 for details).
Acquiring the extra references prevents this failure.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Reported-by: NRussell King - ARM Linux <linux@arm.linux.org.uk>
Reported-by: NOlivier Sobrie <olivier@sobrie.be>
Tested-by: NOlivier Sobrie <olivier@sobrie.be>
Cc: stable <stable@vger.kernel.org> # 3.19
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      524134d4
  5. 10 1月, 2015 1 次提交
    • S
      usb: core: buffer: smallest buffer should start at ARCH_DMA_MINALIGN · 5efd2ea8
      由 Sebastian Andrzej Siewior 提交于 
      the following error pops up during "testusb -a -t 10"
| musb-hdrc musb-hdrc.1.auto: dma_pool_free buffer-128,	f134e000/be842000 (bad dma)
hcd_buffer_create() creates a few buffers, the smallest has 32 bytes of
size. ARCH_KMALLOC_MINALIGN is set to 64 bytes. This combo results in
hcd_buffer_alloc() returning memory which is 32 bytes aligned and it
might by identified by buffer_offset() as another buffer. This means the
buffer which is on a 32 byte boundary will not get freed, instead it
tries to free another buffer with the error message.

This patch fixes the issue by creating the smallest DMA buffer with the
size of ARCH_KMALLOC_MINALIGN (or 32 in case ARCH_KMALLOC_MINALIGN is
smaller). This might be 32, 64 or even 128 bytes. The next three pools
will have the size 128, 512 and 2048.
In case the smallest pool is 128 bytes then we have only three pools
instead of four (and zero the first entry in the array).
The last pool size is always 2048 bytes which is the assumed PAGE_SIZE /
2 of 4096. I doubt it makes sense to continue using PAGE_SIZE / 2 where
we would end up with 8KiB buffer in case we have 16KiB pages.
Instead I think it makes sense to have a common size(s) and extend them
if there is need to.
There is a BUILD_BUG_ON() now in case someone has a minalign of more than
128 bytes.

Cc: stable@vger.kernel.org
Signed-off-by: NSebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5efd2ea8
  7. 13 12月, 2014 1 次提交
  9. 04 12月, 2014 1 次提交
  11. 25 11月, 2014 1 次提交
  13. 20 11月, 2014 1 次提交
  15. 04 11月, 2014 8 次提交
  17. 29 9月, 2014 4 次提交
  19. 25 9月, 2014 1 次提交
    • M
      usb: Add LED triggers for USB activity · 0cfbd328
      由 Michal Sojka 提交于 
      With this patch, USB activity can be signaled by blinking a LED. There
are two triggers, one for activity on USB host and one for USB gadget.

Both triggers should work with all host/device controllers. Tested only
with musb.

Performace: I measured performance overheads on ARM Cortex-A8 (TI
AM335x) running on 600 MHz.

Duration of usb_led_activity():
- with no LED attached to the trigger:        2 ± 1 µs
- with one GPIO LED attached to the trigger:  2 ± 1 µs or 8 ± 2 µs (two peaks in histogram)

Duration of functions calling usb_led_activity() (with this patch
applied and no LED attached to the trigger):
- __usb_hcd_giveback_urb():    10 - 25 µs
- usb_gadget_giveback_request(): 2 - 6 µs
Signed-off-by: NMichal Sojka <sojka@merica.cz>
Acked-by: NFelipe Balbi <balbi@ti.com>
Tested-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      0cfbd328
  21. 24 9月, 2014 12 次提交
  23. 11 9月, 2014 1 次提交
  25. 28 8月, 2014 1 次提交
  27. 27 8月, 2014 1 次提交
  29. 20 8月, 2014 2 次提交
  31. 02 8月, 2014 1 次提交