On Thu, Sep 15, 2022 at 8:28 AM Marcus Folkesson <marcus.folkesson@xxxxxxxxx> wrote: > > Hi Benjamin, > > On Tue, Aug 30, 2022 at 02:45:11PM +0200, Benjamin Tissoires wrote: > > On Thu, Aug 25, 2022 at 8:44 AM Marcus Folkesson > > <marcus.folkesson@xxxxxxxxx> wrote: > > > > > > [...] > > > > > > > > > Is the fact that more than one button share the same > > > byte hard to describe in the report? > > > > No, this is actually easy to describe. You say that there is one usage > > of "something" which has a report size of 1 bit, and then you have > > another usage of "something else" with the same report size. > > > > But usually you have to add padding after to make up to 8 bits (so 6 > > bits in that case). > > > > I was referring to the case where you are parsing the same bit on the > > wire, and give a different usage based if you have received an odd or > > an even number of reports. In that case, we probably need to use move > > this bit to a const field in the original report descriptor and say > > that the data is now not const: > > > > - initial report (completely random example): > > X (2 bytes) | Y (2 bytes) | button this_or_that (1 bit, depending of > > odd or even received reports) | 7 bits of padding > > - we can declare it as: > > X (2 bytes) | Y (2 bytes) | button this (1 bit) | button that (1 > > bit) | 6 bits of padding > > How about if there is no unused bytes? > > The XTRG2FMS has 8 10-bit channels and use every byte in the report. > Should I specify 8 8-bit channels instead and fix that in raw_event? > If so, should I only use 8bit values then? If I am not wrong, you should be able to add another byte in the report descriptor, as long as your raw_event function always adds it. Though now that I am typing it, I am actually wondering if this will work. You can always try, there is a chance it'll work, but I can't remember if it'll result in a timeout on the USB front because it'll expect one more byte that will never arrive. > > (Are you at the ELCE conference btw?) I was at Plumbers this week, but got an extra day today. But yeah, I'm in Dublin today. Cheers, Benjamin > > Best regards > Marcus Folkesson
