This allows workqueue users to run just their own pending work, rather
than wait for the whole workqueue to finish running.  This solves the
deadlock with networking libphy that was due to other workqueue entries
possibly needing a lock that was held by the routine that wanted to
flush its own work.

It's not wonderful: if you absolutely need to synchronize with the work
function having been executed, any user strictly speaking should have
its own completion tracking logic, since when we run things explicitly
by hand, the generic workqueue layer can no longer help us synchronize.

Also, this is strictly only usable for work that has been scheduled
without any delayed timers.  You can not mix the new interface with
schedule_delayed_work().

But it's better than what we had currently.

Acked-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

* genphy_update_link is now exported
* Added a fix from ncase@xes-inc.com which changes forcing so it
  only updates the link.  Otherwise, it never tries the lower
  values, since it is always overwriting the speed/duplex values
  with the current ones, rather than the intended ones.
* Fixed a bug where bringing up a PHY with no link caused it to
  timeout, and enter forcing mode.  Once in forcing mode,
  plugging in the link didn't autonegotiate.  Now the AN state
  detects the lack of link, and enters the NO_LINK state.  AN
  only times out if the link is up and AN fails
* Cleaned up the PHY_AN case, reducing one level of indentation
  for the timeout code.

Signed-off-by: Jeff Garzik <jeff@garzik.org>

 This patch fixes a couple of problems discovered with interrupt handling
in the phylib core, namely:

1. The driver uses timer and workqueue calls, but does not include
   <linux/timer.h> nor <linux/workqueue.h>.

2. The driver uses schedule_work() for handling interrupts, but does not
   make sure any pending work scheduled thus has been completed before
   driver's structures get freed from memory.  This is especially
   important as interrupts may keep arriving if the line is shared with
   another PHY.

   The solution is to ignore phy_interrupt() calls if the reported device
   has already been halted and calling flush_scheduled_work() from
   phy_stop_interrupts() (but guarded with current_is_keventd() in case
   the function has been called through keventd from the MAC device's
   close call to avoid a deadlock on the netlink lock).

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>

patch-mips-2.6.18-20060920-phy-irq-16
Signed-off-by: Jeff Garzik <jeff@garzik.org>

Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

Prevent phylib from freeing PHY IRQ twice on closing an eth device:
phy_disconnect() first calls phy_stop_interrupts(), then it calls
phy_stop_machine() which in turn calls phy_stop_interrupts() making the
kernel complain on each bootup...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Add the PHY_ID_FMT macro to ensure that the format of the id string used by a
driver to match to its specific phy is consistent between the mdio_bus and the
driver.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

Unused, and causes the files to be needlessly rebuilt in some cases.

This patch adds back the code that was taken out, thus re-enabling:

* The PHY Layer to initialize without crashing
* Drivers to actually connect to PHYs
* The entire PHY Control Layer

This patch is used by the gianfar driver, and other drivers which are in
development.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

- unexport symbols never used outside of home module
- remove dead code
- remove CONFIG_PHYCONTROL, make it unconditionally enabled

Includes fixes for problems noted by Adrian Bunk, Andrew Morton,
and one other person lost in the annals of history (and email folders).

ethernet drivers to remain as ignorant as is reasonable of the connected
PHY's design and operation details.

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>