linux/drivers/staging/nvec
Linus Torvalds 033d9959ed Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue changes from Tejun Heo:
 "This is workqueue updates for v3.7-rc1.  A lot of activities this
  round including considerable API and behavior cleanups.

   * delayed_work combines a timer and a work item.  The handling of the
     timer part has always been a bit clunky leading to confusing
     cancelation API with weird corner-case behaviors.  delayed_work is
     updated to use new IRQ safe timer and cancelation now works as
     expected.

   * Another deficiency of delayed_work was lack of the counterpart of
     mod_timer() which led to cancel+queue combinations or open-coded
     timer+work usages.  mod_delayed_work[_on]() are added.

     These two delayed_work changes make delayed_work provide interface
     and behave like timer which is executed with process context.

   * A work item could be executed concurrently on multiple CPUs, which
     is rather unintuitive and made flush_work() behavior confusing and
     half-broken under certain circumstances.  This problem doesn't
     exist for non-reentrant workqueues.  While non-reentrancy check
     isn't free, the overhead is incurred only when a work item bounces
     across different CPUs and even in simulated pathological scenario
     the overhead isn't too high.

     All workqueues are made non-reentrant.  This removes the
     distinction between flush_[delayed_]work() and
     flush_[delayed_]_work_sync().  The former is now as strong as the
     latter and the specified work item is guaranteed to have finished
     execution of any previous queueing on return.

   * In addition to the various bug fixes, Lai redid and simplified CPU
     hotplug handling significantly.

   * Joonsoo introduced system_highpri_wq and used it during CPU
     hotplug.

  There are two merge commits - one to pull in IRQ safe timer from
  tip/timers/core and the other to pull in CPU hotplug fixes from
  wq/for-3.6-fixes as Lai's hotplug restructuring depended on them."

Fixed a number of trivial conflicts, but the more interesting conflicts
were silent ones where the deprecated interfaces had been used by new
code in the merge window, and thus didn't cause any real data conflicts.

Tejun pointed out a few of them, I fixed a couple more.

* 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (46 commits)
  workqueue: remove spurious WARN_ON_ONCE(in_irq()) from try_to_grab_pending()
  workqueue: use cwq_set_max_active() helper for workqueue_set_max_active()
  workqueue: introduce cwq_set_max_active() helper for thaw_workqueues()
  workqueue: remove @delayed from cwq_dec_nr_in_flight()
  workqueue: fix possible stall on try_to_grab_pending() of a delayed work item
  workqueue: use hotcpu_notifier() for workqueue_cpu_down_callback()
  workqueue: use __cpuinit instead of __devinit for cpu callbacks
  workqueue: rename manager_mutex to assoc_mutex
  workqueue: WORKER_REBIND is no longer necessary for idle rebinding
  workqueue: WORKER_REBIND is no longer necessary for busy rebinding
  workqueue: reimplement idle worker rebinding
  workqueue: deprecate __cancel_delayed_work()
  workqueue: reimplement cancel_delayed_work() using try_to_grab_pending()
  workqueue: use mod_delayed_work() instead of __cancel + queue
  workqueue: use irqsafe timer for delayed_work
  workqueue: clean up delayed_work initializers and add missing one
  workqueue: make deferrable delayed_work initializer names consistent
  workqueue: cosmetic whitespace updates for macro definitions
  workqueue: deprecate system_nrt[_freezable]_wq
  workqueue: deprecate flush[_delayed]_work_sync()
  ...
2012-10-02 09:54:49 -07:00
..
Kconfig staging: nvec: do not depend on MACH_PAZ00 2012-09-04 13:18:15 -07:00
Makefile staging: nvec: rename led driver to board specific paz00 driver 2012-06-25 10:55:38 -07:00
README
TODO staging: nvec: update ToDo list 2011-09-29 17:40:39 -07:00
nvec-keytable.h staging: nvec: coding style fixes / add copyright notice 2011-09-29 17:40:37 -07:00
nvec.c Merge branch 'for-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2012-10-02 09:54:49 -07:00
nvec.h staging:nvec:nvec.h Fix typos in staging:nvec 2012-04-10 09:29:21 -07:00
nvec_kbd.c staging: nvec: add remove function to nvec childs 2012-06-25 10:55:38 -07:00
nvec_paz00.c staging: nvec: rename led driver to board specific paz00 driver 2012-06-25 10:55:38 -07:00
nvec_power.c staging: nvec: add remove function to nvec childs 2012-06-25 10:55:38 -07:00
nvec_ps2.c staging: nvec: add remove function to nvec childs 2012-06-25 10:55:38 -07:00

README

NVEC: An NVidia compliant Embedded Controller Protocol Implemenation

This is an implementation of the NVEC protocol used to communicate with an
embedded controller (EC) via I2C bus. The EC is an I2C master while the host
processor is the I2C slave. Requests from the host processor to the EC are
started by triggering a gpio line.

There is no written documentation of the protocol available to the public,
but the source code[1] of the published nvec reference drivers can be a guide.
This driver is currently only used by the AC100 project[2], but it is likely,
that other Tegra boards (not yet mainlined, if ever) also use it.

[1] e.g. http://nv-tegra.nvidia.com/gitweb/?p=linux-2.6.git;a=tree;f=arch/arm/mach-tegra/nvec;hb=android-tegra-2.6.32
[2] http://gitorious.org/ac100, http://launchpad.net/ac100