dmaengine: mcf-edma: utilize edma_write_tcdreg() macro for TCD Access

The TCD structure has undergone modifications, incorporating fields
extended to 64 bits. When TCD64 is enabled, the TCD type shifts to
'void *'. Use of the edma_write_tcdreg() macro to facilitate TCD register
access.

Add cpu_to_le32(0) to ensure little-endian compatibility with TCD
registers and avoid a build warning.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20231221153528.1588049-5-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: mcf-edma-main: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230919133207.1400430-22-u.kleine-koenig@pengutronix.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: fsl-edma: move tcd into struct fsl_dma_chan

Relocates the tcd into the fsl_dma_chan structure. This adjustment reduces
the need to reference back to fsl_edma_engine, paving the way for EDMA V3
support.

Unified the edma_writel and edma_writew functions for accessing TCD
(Transfer Control Descriptor) registers. A new macro is added that can
automatically detect whether a 32-bit or 16-bit access should be used
based on the structure field definition. This provide better support
64-bit TCD with future v5 version.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202305271951.gmRobs3a-lkp@intel.com/
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20230821161617.2142561-11-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: fsl-edma: move common IRQ handler to common.c

Move the common part of IRQ handler from fsl-edma-main.c and
mcf-edma-main.c to fsl-edma-common.c. This eliminates redundant code, as
the both files contains mostly identical code.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20230821161617.2142561-6-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: fsl-edma: Remove enum edma_version

The enum edma_version, which defines v1, v2, and v3, is a software concept
used to distinguish IP differences. However, it is not aligned with the
chip reference manual. According to the 7ulp reference manual, it should
be edma2. In the future, there will be edma3, edma4, and edma5, which
could cause confusion. To avoid this confusion, remove the edma_version
and instead use drvdata->flags to distinguish the IP difference.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20230821161617.2142561-5-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

dmaengine: fsl-edma: clean up EXPORT_SYMBOL_GPL in fsl-edma-common.c

Exported functions in fsl-edma-common.c are only used within
fsl-edma.c and mcf-edma.c. Global export is unnecessary.

This commit removes all EXPORT_SYMBOL_GPL in fsl-edma-common.c,
and renames fsl-edma.c and mcf-edma.c to maintain the same
final module names as before, thereby simplifying the codebase.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20230821161617.2142561-3-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>