(expanded cc list) On Fri, Nov 26, 2010 at 08:39:25AM -0500, Andy Walls wrote: > You might want to check the handling against this NEC datasheet > > http://www.datasheetcatalog.org/datasheet/nec/UPD6122G-002.pdf > > The datasheet calls the address bytes "custom code" (high byte apparently) > and "custom code'" (low byte apparently) with both bytes sent lsb first. It > appears the high byte is sent first when using 16 bit codes.
Thanks for the link Andy. You appear to be correct, which suggests that winbond-cir is the "wrong" one. Curiously there is a comment in winbond-cir.c which explicitly mentions which byte is which: 854 * With NEC extended, Address1 is the LSB of the Address and 855 * Address2 is the MSB, Command parsing remains unchanged. but then it also says: 25 * To do: 26 * o Test NEC and RC5 I suppose its all a matter of convention, but I think they should at least be consistent, so I'll go by the NEC datasheet and submit a patch to winbond-cir instead. Cheers James > James Hogan <ja...@albanarts.com> wrote: > > >Could somebody check this as I'm unable to test it. > > > >I'm also not entirely certain it isn't winbond-cir that is in error > >instead of ir-nec-decoder. > > > >Cheers > >James > >-- > >After comparing the extended NEC scancode construction of the software > >decoder and winbond-cir it appears the software decoder is putting the > >two address bytes the wrong way around. > > > >Here's how the decoders currently generate scancodes: > >winbond-cir normal NEC: msb [ 0x0, 0x0, addr, cmd ] lsb > >soft normal NEC: msb [ 0x0, 0x0, addr, cmd ] lsb > >winbond-cir extended NEC: msb [ 0x0, not_addr, addr, cmd ] lsb > >soft extended NEC: msb [ 0x0, addr, not_addr, cmd ] lsb > > > >The soft decider is not consistent with [1], assuming the "Address high" > >byte (not_addr) should be more significant than the "Address low" byte > >(addr) in the scancode. > > > >[1] http://www.sbprojects.com/knowledge/ir/nec.htm > > > >Signed-off-by: James Hogan <ja...@albanarts.com> > >--- > > drivers/media/IR/ir-nec-decoder.c | 4 ++-- > > 1 files changed, 2 insertions(+), 2 deletions(-) > > > >diff --git a/drivers/media/IR/ir-nec-decoder.c > >b/drivers/media/IR/ir-nec-decoder.c > >index 70993f7..11d3e78 100644 > >--- a/drivers/media/IR/ir-nec-decoder.c > >+++ b/drivers/media/IR/ir-nec-decoder.c > >@@ -166,8 +166,8 @@ static int ir_nec_decode(struct input_dev > >*input_dev, struct ir_raw_event ev) > > > > if ((address ^ not_address) != 0xff) { > > /* Extended NEC */ > >- scancode = address << 16 | > >- not_address << 8 | > >+ scancode = not_address << 16 | > >+ address << 8 | > > command; > > IR_dprintk(1, "NEC (Ext) scancode 0x%06x\n", scancode); > > } else { -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
