Dear Takashi Kanamaru, On Wed, Jun 12, 2019 at 11:08:34PM +0900, Takashi Kanamaru wrote: > Dear all, > > When using kernel 4.19.X and sending IR commands with LIRC, > the number of pulse-spaces of IR sequence is restricted to be smaller than 256. > > In kernel 4.19, this restriction is caused by the following line in > media/rc/lirc_dev.c, > which did not exist kernel 4.14. > https://github.com/torvalds/linux/blob/v4.19/drivers/media/rc/lirc_dev.c Indeed this file did not exist in 4.14. In 4.14, it was called: https://github.com/torvalds/linux/blob/v4.14/drivers/media/rc/ir-lirc-codec.c > #define LIRCBUF_SIZE 256 > > An IR sequences of a remote controller of my air conditioner has 439 > pulse-spaces > with about 250ms duration, so, it cannot be sent with kernel 4.19. There are a lot of IR drivers/hardware that can send more than 256 pulse/spaces. This limit exists in rc-core because it was always there; however some old lirc drivers did not have a limit. I don't see any reason why it can't be increased. For the record, it would be interesting to know what your air conditioner model is and what the IR signal looks like. I have not seen such a signal before. > The max duration of IR sequence is detemined as 500ms by IR_MAX_DURATION. > Therefore, I think signals with about 1000 pulse-spaces should be allowed. > > So, could you please set LIRCBUF_SIZE to the value 1024? I don't see any reason not to. > I built a kernel 4.19.46 with LIRCBUF_SIZE=1024, > and I confirmed that IR sequences with 439 pulse-spaces > could be sent correctly. That's great. Thanks, Sean
