Messages in this thread | | | Subject | Re: 2.6.3-bk7 i8042 does not work on a genuine i386 ibm ps/2 model 70. | From | (Eric W. Biederman) | Date | 03 Mar 2004 11:51:33 -0700 |
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Vojtech Pavlik <vojtech@suse.cz> writes:
> On Sun, Feb 29, 2004 at 07:32:19AM -0700, Eric W. Biederman wrote: > > > > The i8042 driver attempts to detect if IBM PC compatiblity mode i.e. > > I8042_CTR_XLATE is enabled. Unfortunately on a genuine IBM PS/2, (a pc > > incompatible :) this does not work. > > > > In i8042_controller_init if I disable the detection of the keyboard > > not being in XLATE mode everything works fine. > > > > /* > > * If the chip is configured into nontranslated mode by the BIOS, don't > > * bother enabling translating and be happy. > > */ > > #if 0 > > > > if (~i8042_ctr & I8042_CTR_XLATE) > > i8042_direct = 1; > > #endif > > > > > > The value of i8042_initial_ctr is 0x25 in case that helps. > > > > I am not certain where to proceed from here. > > This bit is an equivalent to 2.4 code in pc_keyb.c, that adds a > workaround for IBM PowerPC portables, which don't seem to support > translated mode: > > /* ibm powerpc portables need this to use scan-code set 1 -- Cort * */ > if (!(kbd_write_command_w_and_wait(KBD_CCMD_READ_MODE) & KBD_MODE_KCC)) > { > /* > * If the controller does not support conversion, > * Set the keyboard to scan-code set 1. > */ > kbd_write_output_w(0xF0); > kbd_wait_for_input(); > kbd_write_output_w(0x01); > kbd_wait_for_input(); > } > > As you can see, this sets the keyboard to scancode set 1, if > KBD_MODE_KCC (which is 0x40, same as I8042_CTR_XLATE), bit is set. > > This should break your keyboard as well, if it supports mode setting. > > I guess we could kill that bit, and ignore the old PowerPCs ....
I will check what happens this evening. But that sounds exactly what is happening with my keyboard. The scan codes I see are in set 1.
> > The piece I am certain about is that the keyboard controller has > > traditionally been a tiny microcontroller on PCs so that there is a > > wide variance in the commands and the exact format that they support. > > Yes. The translate/don't bit is documented by IBM, though.
Any pointers to the docs?
> > And so far every data sheet I have looked at the documentation is > > slightly different. The only real intel datasheet I could find was > > for the i8741A. And it does not document the traditional interface > > implemented but the i8042, because that was done in firmware. > > > > This machine is primarily a test machine to make certain my code > > works on older hardware. So I am willing try any interesting or > > likely patches. > > Does the machine by any chance have a PS/2 mouse port? If not, it may be > the reason - it would have an AT-style i8042, and those might not be > implementing that bit.
Yes. But the plugs are clearly labeled which is for the keyboard and which is for the mouse.
> We could skip the above check if we don't detect the AUX port.
Interesting.
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