Some spinlocks are not properly initialized on ir core:

[  471.714132] BUG: spinlock bad magic on CPU#0, modprobe/1899
[  471.719838]  lock: f92a08ac, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[  471.727301] Pid: 1899, comm: modprobe Not tainted 2.6.33 #36
[  471.733062] Call Trace:
[  471.735537]  [<c1498793>] ? printk+0x1d/0x22
[  471.739866]  [<c12694e3>] spin_bug+0xa3/0xf0
[  471.744224]  [<c126962d>] do_raw_spin_lock+0x7d/0x160
[  471.749364]  [<f92a01ff>] ? ir_rc5_register+0x6f/0xf0 [ir_rc5_decoder]

So, use static initialization for the static spinlocks, instead of the
dynamic ones (currently used), as proposed by David Härdeman on one
of his RFC patches.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Reimplement the RC-5 decoder state machine. Code is now clear, and works
properly. It is also simpler than the previous implementations.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

A previous cleanup patch removed more than needed. Re-add the logic that
disable the decoders.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Now that the decoders are state machine, there's no need to create
an ancillary buffer while decoding the protocol. Just call the decoders
code directly, event by event.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This decoder is also based on a state machine, just like the NEC protocol
decoder. It is pedantic in the sense that accepts only 14 bits. As there
are some variants that outputs less bits, it needs to be improved to also
handle those.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Remove dead code and properly name a few constants
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Thanks to Andy Walls <awalls@md.metrocast.net> for pointing me his
code, that gave me some ideas to better implement it.

After some work with saa7134 bits, I found a way to catch both IRQ
edge pulses. By enabling it, the NEC decoder can now take both
pulse and spaces into account, making it more precise.

Instead of the old strategy of handling the events all at once,
this code implements a state machine. Due to that, it handles
individual pulse or space events, validating them against the
protocol, producing a much more reliable decoding.

With the new implementation, the protocol trailer bits are properly
handled, making possible for the repeat key to work.

Also, the code is now capable of handling both NEC and NEC extended
IR devices. With NEC, it produces a 16 bits code, while with NEC
extended, a 24 bits code is returned.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Rewrites the keyup/keydown logic in drivers/media/IR/ir-keytable.c.

All knowledge of keystates etc is now internal to ir-keytable.c
and not scattered around ir-raw-event.c and ir-nec-decoder.c (where
it doesn't belong).

In addition, I've changed the API slightly so that ir_input_dev is
passed as the first argument rather than input_dev. If we're ever
going to support multiple keytables we need to move towards making
ir_input_dev the main interface from a driver POV and obscure away
the input_dev as an implementational detail in ir-core.
Signed-off-by: NDavid Härdeman <david@hardeman.nu>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

With the help of raw_register/raw_unregister, adds a sysfs group
associated with the decoder, inside the corresponding irrcv node.

Writing 1 to nec_decoder/enabled enables the decoder, while
writing 0 disables it.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Some decoders and a lirc_dev interface may need some other operations to work.
For example: IR device register/unregister and ir_keydown events may need to
be tracked.

As some operations can occur in interrupt time, and a lock is needed to prevent
un-registering a decode while decoding a key, the lock needed to be convert
into a spin lock.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Instead of hardcoding the protocols into ir-core, add a register interface
for the IR protocol decoders, and convert ir-nec-decoder into a client of
ir-core.

With this approach, it is possible to dynamically load the needed IR protocols,
and to add a RAW IR interface module, registered as one IR raw protocol decoder.

This patch opens a way to register a lirc_dev interface to work as an userspace
IR protocol decoder.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

At raw_decode mode, the key is processed after the end of a timer. The
previous code resets the timer every time something is received at the IR
port. While this works fine with IR's that don't implement repeat, like
Avermedia RM-JX IR, it keeps waiting until keydown, on IR's that implement
NEC repeat command, like the Terratec yellow.

The solution is to change the behaviour to do the timeout after the first
received data.

The timeout is currently set to 15 ms, as it works fine with NEC protcocol.
It may need some adjustments to support other protocols and to better handle
spurious detections that may happen with some IR sensors.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Adds a method to pass IR raw pulse/code events into ir-core. This is
needed in order to support LIRC. It also helps to move common code
from the drivers into the core.

In order to allow testing, it implements a simple NEC protocol decoder
at ir-nec-decoder.c file. The logic is about the same used at saa7134
driver that handles Avermedia M135A and Encore FM53 boards.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>