Re: i8042 access timings

From: Dmitry Torokhov
Date: Wed Jan 26 2005 - 11:42:39 EST


On Wed, 26 Jan 2005 16:43:07 +0100, Vojtech Pavlik <vojtech@xxxxxxx> wrote:
> On Tue, Jan 25, 2005 at 02:41:14AM -0500, Dmitry Torokhov wrote:
> > @@ -213,7 +217,10 @@
> > if (!retval)
> > for (i = 0; i < ((command >> 8) & 0xf); i++) {
> > if ((retval = i8042_wait_read())) break;
> > - if (i8042_read_status() & I8042_STR_AUXDATA)
> > + udelay(I8042_STR_DELAY);
> > + str = i8042_read_status();
> []
> > + udelay(I8042_DATA_DELAY);
> > + if (str & I8042_STR_AUXDATA)
> > param[i] = ~i8042_read_data();
> > else
> > param[i] = i8042_read_data();
>
> We may as well drop the negation. It's a bad way to signal the data came
> from the AUX port. Then we don't need the extra status read and can just
> proceed to read the data, since IMO we don't need to wait inbetween,
> even according to the IBM spec.

Do you remember why it has been done to begin with?

--
Dmitry
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