include: add SPDX GPL-2.0-only license tags where applicable ...

Interpret "GPLv2" as "GPLv2 only".

Signed-off-by: Roland Hieber <rohieb@rohieb.name>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

driver: Adopt DMA mask concept from Linux ...

In order to be able to detect cases where DMA isn't capable of
reaching every memory address, port the concept of DMA mask,
dma_set_mask() function and add appropriate check to
dma_mapping_error().

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

dma: Add prototypes for dma mapping functions ...

Right now we only have the dma_sync_single_* functions, but no functions
for actually mapping a pointer. The mapping functions become necessary
when casting a pointer to unsigned long to get a dma address is not
enough. (I'm not even going so far that we'll add IOMMU support, but on
some architectures we need a place where we can check if a pointer is
DMA mappable at all)

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

dma: Use dma_addr_t as type for DMA addresses ...

DMA addresses are not necessarily the same as unsigned long. Fix
the type for the dma_sync_single_* operations.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

implement dma_alloc_writecombine ...

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

ARM: move DMA alloc functions to dma.h ...

This better separates the DMA from the MMU functionality.

Also move all drivers that only depends on asm/mmu.h for the alloc
functions over to the common header.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

dma: add streaming DMA ops ...

This will allow us to implement cache maintenance in a platform
agnostic way.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

blackfin, mips, openrisc, ppc, sandbox, x86: add generic dma_alloc, dma_free inlines ...

Some drivers call dma_inv_range() on buffers, on arm these buffers must
be cache line aligned. This patch introduces a generic dma_alloc,
dma_free. Archs can implement in their own functions in "asm/dma.h" and add a:

	#define dma_alloc dma_alloc
	#define dma_free dma_free

On all other archs the generic versions, which translate into xmalloc
and free are used.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>