• Jarod Wilson's avatar
    V4L/DVB: IR: let all protocol decoders have a go at raw data · c2284261
    Jarod Wilson authored
    On Fri, May 28, 2010 at 3:59 PM, Jarod Wilson <jarod@redhat.com> wrote:
    > The mceusb driver I'm about to submit handles just about any raw IR you
    > can throw at it. The ir-core loads up all protocol decoders, starting
    > with NEC, then RC5, then RC6. RUN_DECODER() was trying them in the same
    > order, and exiting if any of the decoders didn't like the data. The
    > default mceusb remote talks RC6(6A). Well, the RC6 decoder never gets a
    > chance to run unless you move the RC6 decoder to the front of the list.
    >
    > What I believe to be correct is to have RUN_DECODER keep trying all of
    > the decoders, even when one triggers an error. I don't think the errors
    > matter so much as it matters that at least one was successful -- i.e.,
    > that _sumrc is > 0. The following works for me w/my mceusb driver and
    > the default decoder ordering -- NEC and RC5 still fail, but RC6 still
    > gets a crack at it, and successfully does its job.
    >
    > Signed-off-by: Jarod Wilson <jarod@redhat.com>
    >
    > ---
    >  drivers/media/IR/ir-raw-event.c |    7 ++++---
    >
    > diff --git a/drivers/media/IR/ir-raw-event.c b/drivers/media/IR/ir-raw-event.c
    > index ea68a3f..44162db 100644
    > --- a/drivers/media/IR/ir-raw-event.c
    > +++ b/drivers/media/IR/ir-raw-event.c
    > @@ -36,14 +36,15 @@ static DEFINE_SPINLOCK(ir_raw_handler_lock);
    >  */
    >  #define RUN_DECODER(ops, ...) ({                                           \
    >        struct ir_raw_handler           *_ir_raw_handler;                   \
    > -       int _sumrc = 0, _rc;                                                \
    > +       int _sumrc = 0, _rc, _fail;                                         \
    >        spin_lock(&ir_raw_handler_lock);                                    \
    >        list_for_each_entry(_ir_raw_handler, &ir_raw_handler_list, list) {  \
    >                if (_ir_raw_handler->ops) {                                 \
    >                        _rc = _ir_raw_handler->ops(__VA_ARGS__);            \
    >                        if (_rc < 0)                                        \
    > -                               break;                                      \
    > -                       _sumrc += _rc;                                      \
    > +                               _fail++;                                    \
    > +                       else                                                \
    > +                               _sumrc += _rc;                              \
    
    Self-NAK. The only place we actually *care* about the retval from a
    RUN_DECODER() call is in __ir_input_register(), and currently, its
    looking for retval < 0, which is currently never possible. When we're
    running the decoders, either they fail and return -EINVAL or they
    succeed and return 0, and in the register case, we get either a
    negative error (ex: -ENOMEM from rc6) or 0, so with the above, _sumrc
    will *always* be 0 in the two cases I'm looking at. The third place
    where RUN_DECODER gets called (decoder unregister) doesn't care about
    the retval either. New patch below, including updated comments about
    the macro.
    Signed-off-by: default avatarJarod Wilson <jarod@redhat.com>
    Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@redhat.com>
    c2284261
ir-raw-event.c 6.77 KB