Re: Synaptics Touchpad workaround for strange behavior after Syncloss (With Patch).

From: Peter Berg Larsen
Date: Sun Jan 11 2004 - 07:48:56 EST



On Sun, 11 Jan 2004, Vojtech Pavlik wrote:

> > I dont have a machine with active multiplexing so the the patch is
> > untested. It warns when the mouse is removed, and tries to recover
> > if multiplexing is disabled.
>
> It's nice, but er definitely shouldn't call i8042_enable_mux() from the
> interrupt handler, because i8042_command() waits for characters arriving
> in the interrupt handler, so we could get into rather nasty recursions.

Are you sure? The i8042_command does spin_lock_irqsave(&i8042_lock,
flags), i8042_wait_read, i8042_read_data and unlock. It seems a good place
for me as the 8042s buffer is just flush by the interrupt. Well except for
the fact it is in the interrupt handler :)

I cannot see a simple/fast solution: All data read in the interrupt must
be processed otherwise kbd data might be lost. I dont want
I8042_BUFFER_SIZE calls to serio_rescan/reconnect, as serio is not smart
enought to only do it once. The mux port number(s) must be remembered if
serio is called after the loop. I dont like any further calls to
i8042_flush as it troughs away both kbd and aux data.

hmm, I actually want the handler to look something like:

if (str & I8042_STR_MUXERR)
i8042_handle_aux_data
else
i8042_handle_kbd_data

That way i8042_flush can call handle_*_data depending on what to flush.

Peter



-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/