dma: edma: remove limits on number of slots

Signed-off-by: Joel Fernandes <joelf@ti.com>
omap_hsmmc: remove sg_limits

Signed-off-by: Joel Fernandes <joelf@ti.com>
Enable various temporary debug statements

Signed-off-by: Joel Fernandes <joelf@ti.com>
ARM: edma: Add function to manually trigger an EDMA channel

Signed-off-by: Joel Fernandes <joelf@ti.com>
dma: edma: Find missed events and issue them

In an effort to move to using Scatter gather lists of any size with
EDMA as discussed at [1] instead of placing limitations on the driver,
we work through the limitations of the EDMAC hardware to find missed
events and issue them.

The sequence of events that require this are:

For the scenario where MAX slots for an EDMA channel is 3:

SG1 -> SG2 -> SG3 -> SG4 -> SG5 -> SG6 -> Null

The above SG list will have to be DMA'd in 2 sets:

(1) SG1 -> SG2 -> SG3 -> Null
(2) SG4 -> SG5 -> SG6 -> Null

After (1) is succesfully transferred, the events from the MMC controller
donot stop coming and are missed by the time we have setup the transfer
for (2). So here, we catch the events missed as an error condition and
issue them manually.

Signed-off-by: Joel Fernandes <joelf@ti.com>
DMA: EDMA: Leave linked to Null slot instead of DUMMY slot

Dummy slot has been used as a way for missed-events not to be
reported as missing. This has been particularly troublesome for cases
where we might want to temporarily pause all incoming events.

For EDMA DMAC, there is no way to do any such pausing of events as
the occurence of the "next" event is not software controlled.
Using "edma_pause" in IRQ handlers doesn't help as by then the event
in concern from the slave is already missed.

Linking a dummy slot, is seen to absorb these events which we didn't
want to miss. So we don't link to dummy, but instead leave it linked
to NULL set, allow an error condition and detect the channel that
missed it.

Signed-off-by: Joel Fernandes <joelf@ti.com>
Revert "Enable various temporary debug statements"

This reverts commit 626bf0fc7d980619a9240bc49803cf5236982577.