On Thursday 05 October 2023 21:53:44 Sergey Shtylyov wrote:
> On 10/5/23 10:24 PM, Ondrej Zary wrote:
>
> > fit3 protocol driver does not support accessing IDE control registers
> > (device control/altstatus). The DOS driver does not use these registers
> > either (as observed from DOSEMU trace). But the HW seems to be capable
> > of accessing these registers - I simply tried bit 3 and it works!
> >
> > The control register is required to properly reset ATAPI devices or
> > they will be detected only once (after a power cycle).
> >
> > Tested with EXP Computer CD-865 with MC-1285B EPP cable and
> > TransDisk 3000.
> >
> > Signed-off-by: Ondrej Zary <linux@xxxxxxx>
>
> Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
>
> > ---
> > drivers/ata/pata_parport/fit3.c | 14 ++------------
> > 1 file changed, 2 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/ata/pata_parport/fit3.c b/drivers/ata/pata_parport/fit3.c
> > index bad7aa920cdc..d2b81cf2e16d 100644
> > --- a/drivers/ata/pata_parport/fit3.c
> > +++ b/drivers/ata/pata_parport/fit3.c
> [...]
> > @@ -59,11 +53,7 @@ static int fit3_read_regr(struct pi_adapter *pi, int cont, int regr)
> > {
> > int a, b;
> >
> > - if (cont) {
> > - if (regr != 6)
> > - return 0xff;
> > - regr = 7;
> > - }
> > + regr += cont << 3;
>
> So, is regr == 7 instead of 8 intentional?
The original code read ATA_REG_STATUS (7) in context 0 instead of ALT_STATUS (6) in context 1.
--
Ondrej Zary
