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: Adrian Hunter <adrian.hunter@nokia.com> Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
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