1. 04 12月, 2013 3 次提交
  2. 30 10月, 2013 2 次提交
  3. 26 8月, 2013 1 次提交
  4. 13 8月, 2013 2 次提交
  5. 26 7月, 2013 5 次提交
  6. 18 6月, 2013 1 次提交
    • G
      USB: cdc-acm: remove unneeded spin_lock_irqsave/restore on write path · 71c2fb03
      Greg Kroah-Hartman 提交于
      When writing data we were:
      	lock
      	do some work
      	unlock
      	call function
      		lock
      		do some work
      		unlock
      		return
      	return
      
      It turns out, that "function" was only ever called in the one place, so
      instead of locking/unlocking for no good reason, just inline the
      function and only grab the lock once.
      
      This has sped up the pathological case of sending 1 byte packets to a
      loop-back cdc-acm device from 49600 bytes per second to 50100 bytes a
      second on my workstation.  A tiny increase yes, but noticable, and now
      the spinlock isn't the hottest thing on the perf graph anymore.  Yes, we
      are still waiting for the hardware for the most part, but getting rid of
      a spinlock_irq_save() call for every packet is still a good thing.
      
      And we end up deleting lines of code, always a win overall.
      
      This was found by using a Teensy 3.0 device and the test program and
      firmware located at:
      	http://www.pjrc.com/teensy/benchmark_usb_serial_receive.htmlReported-by: NPaul Stoffregen <paul@pjrc.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      71c2fb03
  7. 17 5月, 2013 5 次提交
  8. 20 4月, 2013 1 次提交
  9. 10 4月, 2013 1 次提交
  10. 26 3月, 2013 1 次提交
    • B
      USB: cdc-wdm: implement IOCTL_WDM_MAX_COMMAND · 3edce1cf
      Bjørn Mork 提交于
      Userspace applications need to know the maximum supported message
      size.
      
      The cdc-wdm driver translates between a character device stream
      and a message based protocol.  Each message is transported as a
      usb control message with no further encapsulation or syncronization.
      Each read or write on the character device should translate to
      exactly one usb control message to ensure that message boundaries
      are kept intact.  That means that the userspace application must
      know the maximum message size supported by the device and driver,
      making this size a vital part of the cdc-wdm character device API.
      
      CDC WDM and CDC MBIM functions export the maximum supported
      message size through CDC functional descriptors.  The cdc-wdm and
      cdc_mbim drivers will parse these descriptors and use the value
      chosen by the device.  The only current way for a userspace
      application to retrive the value is by duplicating the descriptor
      parsing. This is an unnecessary complex task, and application
      writers are likely to postpone it, using a fixed value and adding
      a "todo" item.
      
      QMI functions have no way to tell the host what message size they
      support.  The qmi_wwan driver use a fixed value based on protocol
      recommendations and observed device behaviour.  Userspace
      applications must know and hard code the same value.  This scheme
      will break if we ever encounter a QMI device needing a device
      specific message size quirk.  We are currently unable to support
      such a device because using a non default size would break the
      implicit userspace API.
      
      The message size is currently a hidden attribute of the cdc-wdm
      userspace API.  Retrieving it is unnecessarily complex, increasing
      the possibility of drivers and applications using different limits.
      The resulting errors are hard to debug, and can only be replicated
      on identical hardware.
      
      Exporting the maximum message size from the driver simplifies the
      task for the userspace application, and creates a unified
      information source independent of device and function class. It also
      serves to document that the message size is part of the cdc-wdm
      userspace API.
      
      This proposed API extension has been presented for the authors of
      userspace applications and libraries using the current API: libmbim,
      libqmi, uqmi, oFono and ModemManager.  The replies were:
      
      Aleksander Morgado:
       "We do really need max message size for MBIM; and as you say, it may be
        good to have the max message size info also for QMI, so the new ioctl
        seems a good addition. So +1 from my side, for what it's worth."
      
      Dan Williams:
       "Yeah, +1 here.  I'd prefer the sysfs file, but the fact that that
        doesn't work for fd passing pretty much kills it."
      
      No negative replies are so far received.
      
      Cc: Aleksander Morgado <aleksander@lanedo.com>
      Cc: Dan Williams <dcbw@redhat.com>
      Signed-off-by: NBjørn Mork <bjorn@mork.no>
      Acked-by: NOliver Neukum <oliver@neukum.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      3edce1cf
  11. 22 3月, 2013 2 次提交
  12. 19 3月, 2013 2 次提交
  13. 16 3月, 2013 1 次提交
  14. 13 3月, 2013 1 次提交
  15. 12 3月, 2013 1 次提交
  16. 19 1月, 2013 1 次提交
    • J
      tty: Added a CONFIG_TTY option to allow removal of TTY · 4f73bc4d
      Joe Millenbach 提交于
      The option allows you to remove TTY and compile without errors. This
      saves space on systems that won't support TTY interfaces anyway.
      bloat-o-meter output is below.
      
      The bulk of this patch consists of Kconfig changes adding "depends on
      TTY" to various serial devices and similar drivers that require the TTY
      layer.  Ideally, these dependencies would occur on a common intermediate
      symbol such as SERIO, but most drivers "select SERIO" rather than
      "depends on SERIO", and "select" does not respect dependencies.
      
      bloat-o-meter output comparing our previous minimal to new minimal by
      removing TTY.  The list is filtered to not show removed entries with awk
      '$3 != "-"' as the list was very long.
      
      add/remove: 0/226 grow/shrink: 2/14 up/down: 6/-35356 (-35350)
      function                                     old     new   delta
      chr_dev_init                                 166     170      +4
      allow_signal                                  80      82      +2
      static.__warned                              143     142      -1
      disallow_signal                               63      62      -1
      __set_special_pids                            95      94      -1
      unregister_console                           126     121      -5
      start_kernel                                 546     541      -5
      register_console                             593     588      -5
      copy_from_user                                45      40      -5
      sys_setsid                                   128     120      -8
      sys_vhangup                                   32      19     -13
      do_exit                                     1543    1526     -17
      bitmap_zero                                   60      40     -20
      arch_local_irq_save                          137     117     -20
      release_task                                 674     652     -22
      static.spin_unlock_irqrestore                308     260     -48
      Signed-off-by: NJoe Millenbach <jmillenbach@gmail.com>
      Reviewed-by: NJamey Sharp <jamey@minilop.net>
      Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      4f73bc4d
  17. 16 1月, 2013 2 次提交
    • J
      TTY: switch tty_flip_buffer_push · 2e124b4a
      Jiri Slaby 提交于
      Now, we start converting tty buffer functions to actually use
      tty_port. This will allow us to get rid of the need of tty in many
      call sites. Only tty_port will needed and hence no more
      tty_port_tty_get in those paths.
      
      Now, the one where most of tty_port_tty_get gets removed:
      tty_flip_buffer_push.
      
      IOW we also closed all the races in drivers not using tty_port_tty_get
      at all yet.
      
      Also we move tty_flip_buffer_push declaration from include/linux/tty.h
      to include/linux/tty_flip.h to all others while we are changing it
      anyway.
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2e124b4a
    • J
      TTY: switch tty_insert_flip_string · 05c7cd39
      Jiri Slaby 提交于
      Now, we start converting tty buffer functions to actually use
      tty_port. This will allow us to get rid of the need of tty in many
      call sites. Only tty_port will needed and hence no more
      tty_port_tty_get in those paths.
      
      tty_insert_flip_string this time.
      Signed-off-by: NJiri Slaby <jslaby@suse.cz>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      05c7cd39
  18. 12 1月, 2013 1 次提交
  19. 16 11月, 2012 1 次提交
  20. 18 10月, 2012 2 次提交
  21. 12 10月, 2012 1 次提交
  22. 11 9月, 2012 1 次提交
  23. 06 9月, 2012 1 次提交
  24. 18 8月, 2012 1 次提交