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Commit 4a694dc9 authored by Adrian Hunter's avatar Adrian Hunter Committed by Pierre Ossman
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omap_hsmmc: Fix response type for busy after response



Some MMC commands result in the card becoming busy after
the response is received.  This needs to be specified
for the omap_hsmmc host controller, which is what this
patch does.  However, the effect is that some commands
with no data will cause a Transfer Complete (TC) interrupt
in addition to the Command Complete (CC) interrupt.
In order to deal with that, the irq handler has needed
a few changes also.

The benefit of this change is that the omap_hsmmc host
controller driver now waits for the TC interrupt while
the card is busy, so the mmc_block driver needs to poll
the card status just once instead of repeatedly.
i.e. the net result is more sleep and less cpu.

The command sequence for open-ended multi-block write
with DMA is now:

	Issue write command CMD25
	Receive CC interrupt
	Data is sent
	Receive TC interrupt (DMA is done)
	Issue stop command CMD12
	Receive CC interrupt
	Card is busy
	Receive TC interrupt
	Card is now ready for next transfer

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: default avatarPierre Ossman <drzeus@drzeus.cx>
parent 82788ff5
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