Date: Tue, 13 May 2014 11:17:58 +0100 From: Maxim Ignatenko <gelraen.ua@gmail.com> To: Ruslan Bukin <br@bsdpad.com> Cc: freebsd-hackers@freebsd.org Subject: Re: Keyboard drivers, polling vs. non-polling mode Message-ID: <CABWTX-Z7Kh1QHCgBeVs6NGzDkfYRCtfctJ5oij-Og5POqB5jEA@mail.gmail.com> In-Reply-To: <20140513084008.GA71115@machdep.com> References: <CABWTX-YViLKRS62cuWcJh=Ma_n3TjU2EEaAcijBzSFXGqiuMDQ@mail.gmail.com> <20140513084008.GA71115@machdep.com>
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On 13 May 2014 09:40, Ruslan Bukin <br@bsdpad.com> wrote: > On Sun, May 11, 2014 at 11:33:42PM +0100, Maxim Ignatenko wrote: >> Hello, >> >> I'm trying trying to get keyboard working in DDB on HP Chromebook 11 (ARM). >> br@ said that it doesn't work there because polling mode is not implemented yet. >> Where can I read about the difference between polling and non-polling >> modes (and about keyboard drivers in general)? >> sys/dev/kbd/kbdreg.h describes some structures and method signatures, >> but I have no clue what is the expected behaviour of those methods. >> >> My current guess is that in polling mode keyboard driver just queues >> up all the input coming from keyboard and then gives it to consumer >> upon request, while in non-polling mode it invokes some callback >> instead of queueing. But I cannot find any documentation to confirm or >> disprove that. >> > > Chrome Embedded Controller (EC) provides interrupt (KB_GPIO_INT pin, active low) > reporting that there are pending data and you need to read the data using > ec_command(..). After all data was read, pin comes to 1 (not active). > > We have no interrupts in KDB, so you have to check pin status manually and > if status == 0 (active) then read new data. > > Probably you can start with patch attached (I did't tested). Thanks, I've tried something like that, except with invoking ec_command immediately and comparing returned state to previous one rather than reading status bit from GPIO pin. I keep getting "fdb0: i2c transfer returned 6" and none of the printfs I've added to iicbus_transfer_gen in sys/dev/iicbus/iiconf.c. -- Best regards, Maxim
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