The following code segment is not functional because the transfer cycle time speficied by
the EIDE device is later overwritten by ata_timing_quantize():
/*
* If the drive is an EIDE drive, it can tell us it needs extended
* PIO/MW_DMA cycle timing.
*/
if (adev->id[ATA_ID_FIELD_VALID] & 2) { /* EIDE drive */
memset(&p, 0, sizeof(p));
(snip)
ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
<== uninitialized "t" is used here
}
/*
* Convert the timing to bus clock counts.
*/
ata_timing_quantize(s, t, T, UT); <== t is overwritten by quantized s
The patch has been submitted for ide-timing.h before:
http://marc.theaimsgroup.com/?l=linux-ide&m=110820013425454&w=2
Resubmitted for libata.
Changes:
- Minor fix to honor the following transfer cycle time speficied by the device
- id[65]: Minimum Multiword DMA transfer cycle time per word
- id[67]: Minimum PIO transfer cycle time without flow control
- id[68]: Minimum PIO transfer cycle time with IORDY
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
=======
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>