On Wed, May 23, 2018 at 02:21:27PM +0200, Daniel Borkmann wrote: > On 05/18/2018 04:07 PM, Sean Young wrote: > > The kernel IR decoders (drivers/media/rc/ir-*-decoder.c) 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, for which lircd is need to decode the IR . > > > > 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. > > It might also be possible to support non-button devices such as analog > > directional pads or air conditioning remote controls and decode the target > > temperature in bpf, and pass that to an input device. > > Mauro, are you fine with this series going via bpf-next? How ugly would this > get with regards to merge conflicts wrt drivers/media/rc/? There are no merge conflict and as of yet, I'm not expecting any. If anything I suspect the bpf tree is more likely to change, so merging via bpf-next might make more sense. Thanks Sean > > Thanks, > Daniel > > > 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 > > > > Changes since v3: > > - Implemented review comments from Quentin Monnet and Y Song (thanks!) > > - More helpful and better formatted bpf helper documentation > > - Changed back to bpf_prog_array rather than open-coded implementation > > - scancodes can be 64 bit > > - bpf gets passed values in microseconds, not nanoseconds. > > microseconds is more than than enough (IR receivers support carriers upto > > 70kHz, at which point a single period is already 14 microseconds). Also, > > this makes it much more consistent with lirc mode2. > > - Since it looks much more like lirc mode2, rename the program type to > > BPF_PROG_TYPE_LIRC_MODE2. > > - Rebased on bpf-next > > > > Changes since v2: > > - Fixed locking issues > > - Improved self-test to cover more cases > > - Rebased on bpf-next again > > > > Changes since v1: > > - Code review comments from Y Song <ys114321@xxxxxxxxx> and > > Randy Dunlap <rdunlap@xxxxxxxxxxxxx> > > - Re-wrote sample bpf to be selftest > > - Renamed RAWIR_DECODER -> RAWIR_EVENT (Kconfig, context, bpf prog type) > > - Rebase on bpf-next > > - Introduced bpf_rawir_event context structure with simpler access checking > > > > Sean Young (3): > > bpf: bpf_prog_array_copy() should return -ENOENT if exclude_prog not > > found > > media: rc: introduce BPF_PROG_LIRC_MODE2 > > bpf: add selftest for lirc_mode2 type program > > > > drivers/media/rc/Kconfig | 13 + > > drivers/media/rc/Makefile | 1 + > > drivers/media/rc/bpf-lirc.c | 308 ++++++++++++++++++ > > drivers/media/rc/lirc_dev.c | 30 ++ > > drivers/media/rc/rc-core-priv.h | 22 ++ > > drivers/media/rc/rc-ir-raw.c | 12 +- > > include/linux/bpf_rcdev.h | 30 ++ > > include/linux/bpf_types.h | 3 + > > include/uapi/linux/bpf.h | 53 ++- > > kernel/bpf/core.c | 11 +- > > kernel/bpf/syscall.c | 7 + > > kernel/trace/bpf_trace.c | 2 + > > tools/bpf/bpftool/prog.c | 1 + > > tools/include/uapi/linux/bpf.h | 53 ++- > > tools/include/uapi/linux/lirc.h | 217 ++++++++++++ > > tools/lib/bpf/libbpf.c | 1 + > > tools/testing/selftests/bpf/Makefile | 8 +- > > tools/testing/selftests/bpf/bpf_helpers.h | 6 + > > .../testing/selftests/bpf/test_lirc_mode2.sh | 28 ++ > > .../selftests/bpf/test_lirc_mode2_kern.c | 23 ++ > > .../selftests/bpf/test_lirc_mode2_user.c | 154 +++++++++ > > 21 files changed, 974 insertions(+), 9 deletions(-) > > create mode 100644 drivers/media/rc/bpf-lirc.c > > create mode 100644 include/linux/bpf_rcdev.h > > create mode 100644 tools/include/uapi/linux/lirc.h > > create mode 100755 tools/testing/selftests/bpf/test_lirc_mode2.sh > > create mode 100644 tools/testing/selftests/bpf/test_lirc_mode2_kern.c > > create mode 100644 tools/testing/selftests/bpf/test_lirc_mode2_user.c > >
