Messages in this thread |  | | | From | Alan Chandler <> | | Subject | Re: ide-cd problem | | Date | Mon, 22 Nov 2004 07:52:28 +0000 |
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On Sunday 21 November 2004 16:13, Alan Chandler wrote: ... > > This seems to be some combination of frequently occuring timing problem, > and the difference treatment in cdrom_newpc_intr to cdrom_pc_intr
I put a ndelay(400) at the head of cdrom_newpc_intr and the problem of DRQ being set when there was no data to transfer disappeared. It appears that my hardware is too slow.
I have been reading the ATA/ATAPI - 6 spec, and it implies that the state of DRQ line need one pio cycle before being correct and that you should read the alternative status register to achieve this. I tried a simple
HWIF(drive)->INB( IDE_ALTSTATUS_REG);
But that made no difference.
-- Alan Chandler alan@chandlerfamily.org.uk First they ignore you, then they laugh at you, then they fight you, then you win. --Gandhi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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