The kernel IR decoders support the most widely used IR protocols, but there are many protocols which are not supported[1]. For example, the lirc-remotes[2] repo has over 2700 remotes, many of which are not supported by rc-core. There is a "long tail" of unsupported IR protocols. IR encoding is done in such a way that some simple circuit can decode it; therefore, bpf is ideal. In order to support all these protocols, here we have bpf based IR decoding. The idea is that user-space can define a decoder in bpf, attach it to the rc device through the lirc chardev. Separate work is underway to extend ir-keytable to have an extensive library of bpf-based decoders, and a much expanded library of rc keymaps. Another future application would be to compile IRP[3] to a IR BPF program, and so support virtually every remote without having to write a decoder for each. Thanks, Sean Young [1] http://www.hifi-remote.com/wiki/index.php?title=DecodeIR [2] https://sourceforge.net/p/lirc-remotes/code/ci/master/tree/remotes/ [3] http://www.hifi-remote.com/wiki/index.php?title=IRP_Notation Sean Young (4): media: rc: introduce BPF_PROG_IR_DECODER media: bpf: allow raw IR decoder bpf programs to be used media: rc bpf: move ir_raw_event to uapi samples/bpf: an example of a raw IR decoder drivers/media/rc/Kconfig | 8 + drivers/media/rc/Makefile | 1 + drivers/media/rc/ir-bpf-decoder.c | 284 ++++++++++++++++++++++ drivers/media/rc/lirc_dev.c | 30 +++ drivers/media/rc/rc-core-priv.h | 15 ++ drivers/media/rc/rc-ir-raw.c | 5 + include/linux/bpf_types.h | 3 + include/media/rc-core.h | 19 +- include/uapi/linux/bpf.h | 17 +- include/uapi/linux/bpf_rcdev.h | 24 ++ kernel/bpf/syscall.c | 7 + samples/bpf/Makefile | 4 + samples/bpf/bpf_load.c | 9 +- samples/bpf/grundig_decoder_kern.c | 112 +++++++++ samples/bpf/grundig_decoder_user.c | 54 ++++ tools/bpf/bpftool/prog.c | 1 + tools/include/uapi/linux/bpf.h | 17 +- tools/testing/selftests/bpf/bpf_helpers.h | 6 + 18 files changed, 594 insertions(+), 22 deletions(-) create mode 100644 drivers/media/rc/ir-bpf-decoder.c create mode 100644 include/uapi/linux/bpf_rcdev.h create mode 100644 samples/bpf/grundig_decoder_kern.c create mode 100644 samples/bpf/grundig_decoder_user.c -- 2.17.0
