Commit 4f701d1e authored Apr 23, 2007 by Alan Cox Committed by Jeff Garzik Apr 28, 2007

ata_timing: ensure t->cycle is always correct



Russell King hit a case where quantisation errors accumulated such that
the cycle time was shorter than rather than equal to the active/recovery
time. The code already knows how to stretch times to fit the cycle time
but does not know about the reverse.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

parent c1c4e8d5

drivers/ata/libata-core.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -2640,6 +2640,12 @@ int ata_timing_compute(struct ata_device *adev, unsigned short speed,
		t->recover = t->cycle - t->active;
		}

		/* In a few cases quantisation may produce enough errors to
		leave t->cycle too low for the sum of active and recovery
		if so we must correct this */
		if (t->active + t->recover > t->cycle)
		t->cycle = t->active + t->recover;

		return 0;
		}