Teach lirc how to send and receive scancodes

This patch series has some general cleanup work, then the lirc scancode interface (v3) and lirc documentation fixes. The cleanups are needed for the new scancode interface.

lirc already supports LIRC_MODE_LIRCCODE, but that mode is entirely driver dependant and makes no provision for protocol information.

Receiving LIRC_MODE_SCANCODE
----------------------------
If a lirc device has the LIRC_CAN_REC_SCANCODE feature, LIRC_MODE_SCANCODE can be set set using LIRC_SET_REC_MODE ioctl. Now when you read from the device you receive struct lirc_scancode. In this structure you have the scancode, rc_type, and flags. RC_TYPE_* is now in uapi, so now you can see exactly which protocol variant was used. flags might contain LIRC_SCANCODE_FLAGS_TOGGLE (rc5, rc6) or LIRC_SCANCODE_FLAGS_REPEAT (nec).

Using this interface, you can see what IR protocol a remote is using. This was not easy to do before.

Sending LIRC_MODE_SCANCODE
--------------------------
If a lirc device has the LIRC_CAN_SEND_SCANCODE features, LIRC_MODE_SCANCODE can be set using the LIRC_SET_SEND_MODE ioctl. Now you can write struct lirc_scancode. flags should be 0, rc_type to the RC_TYPE_* and the scancode must be set. You can only tranmsit one lirc_scancode at a time.

This interface uses the in-kernel IR encoders to work. Using this interface it will be possible to port lirc_zilog to rc-core. This device cannot send raw IR, so it will not use the IR encoders but provide the same userspace interface.

Other user-visible changes
--------------------------
Now all RC devices will have a lirc char device, including devices which do not produce raw IR. They will be fixed in mode LIRC_MODE_SCANCODE.

Changes v2 -> v3:
- add timestamp to lirc_scancode struct to record when scancode was decoded in ktime (CLOCK_MONOTONIC)
- Rather than add more members to rc_dev and ir_raw_event_ctrl, now we have all the lirc settings for rc-core in lirc_node
- Various small fixes.

Changes v1 -> v2:
- changed the scancode to 64 bit. There are many IR protocols which encode more than 32 bits; we don't support any at the moment but might as well future-proof it
http://www.hifi-remote.com/wiki/index.php?title=DecodeIR
- Various small fixes.
- Added documentation

Sean Young (19):
[media] lirc: document lirc modes better
[media] lirc: return ENOTTY when ioctl is not supported [media] lirc: return ENOTTY when device does support ioctl [media] winbond: allow timeout to be set
[media] gpio-ir: do not allow a timeout of 0
[media] rc: lirc keymap no longer makes any sense [media] lirc: advertise LIRC_CAN_GET_REC_RESOLUTION and improve [media] mce_kbd: add encoder
[media] serial_ir: iommap is a memory address, not bool [media] lirc: use refcounting for lirc devices [media] lirc: lirc interface should not be a raw decoder [media] lirc: exorcise struct irctl
[media] lirc: use plain kfifo rather than lirc_buffer [media] lirc: implement scancode sending
[media] rc: use the correct carrier for scancode transmit [media] rc: auto load encoder if necessary
[media] lirc: implement reading scancode
[media] lirc: scancode rc devices should have a lirc device too [media] lirc: document LIRC_MODE_SCANCODE

 Documentation/media/lirc.h.rst.exceptions          |  50 ++-
 Documentation/media/uapi/rc/lirc-dev-intro.rst     |  78 +++-
 Documentation/media/uapi/rc/lirc-get-features.rst  |  28 +-
 Documentation/media/uapi/rc/lirc-get-length.rst    |   3 +-
 Documentation/media/uapi/rc/lirc-get-rec-mode.rst  |   8 +-
 Documentation/media/uapi/rc/lirc-get-send-mode.rst |   8 +-
 Documentation/media/uapi/rc/lirc-read.rst          |  22 +-
 .../media/uapi/rc/lirc-set-rec-carrier-range.rst   |   2 +-
 .../media/uapi/rc/lirc-set-rec-timeout-reports.rst |   2 +
 Documentation/media/uapi/rc/lirc-write.rst         |  25 +-
 drivers/media/rc/Kconfig                           |  15 +-
 drivers/media/rc/Makefile                          |   6 +-
 drivers/media/rc/gpio-ir-recv.c                    |   2 +-
 drivers/media/rc/igorplugusb.c                     |   2 +-
 drivers/media/rc/ir-jvc-decoder.c                  |   1 +
 drivers/media/rc/ir-lirc-codec.c                   | 367 ++++++++++++------
 drivers/media/rc/ir-mce_kbd-decoder.c              |  56 ++-
 drivers/media/rc/ir-nec-decoder.c                  |   1 +
 drivers/media/rc/ir-rc5-decoder.c                  |   1 +
 drivers/media/rc/ir-rc6-decoder.c                  |   1 +
 drivers/media/rc/ir-sanyo-decoder.c                |   1 +
 drivers/media/rc/ir-sharp-decoder.c                |   1 +
 drivers/media/rc/ir-sony-decoder.c                 |   1 +
 drivers/media/rc/keymaps/Makefile                  |   1 -
 drivers/media/rc/keymaps/rc-lirc.c                 |  42 --
 drivers/media/rc/lirc_dev.c                        | 431 +++++++++------------
 drivers/media/rc/rc-core-priv.h                    |  61 ++-
 drivers/media/rc/rc-ir-raw.c                       |  55 ++-
 drivers/media/rc/rc-main.c                         |  73 ++--
 drivers/media/rc/serial_ir.c                       |   4 +-
 drivers/media/rc/st_rc.c                           |   2 +-
 drivers/media/rc/winbond-cir.c                     |   4 +-
 drivers/staging/media/lirc/lirc_sasem.c            |   3 +-
 drivers/staging/media/lirc/lirc_zilog.c            | 167 ++++----
 include/media/lirc_dev.h                           |  33 +-
 include/media/rc-core.h                            |   3 +
 include/media/rc-map.h                             | 109 ++----
 include/uapi/linux/lirc.h                          |  76 ++++
 38 files changed, 1069 insertions(+), 676 deletions(-)
 delete mode 100644 drivers/media/rc/keymaps/rc-lirc.c

2.9.3